Teeth grinding, oral motor performance and maximal bite force in cerebral palsy children.

PubMed

Botti Rodrigues Santos, Maria Teresa; Duarte Ferreira, Maria Cristina; de Oliveira Guaré, Renata; Guimarães, Antonio Sergio; Lira Ortega, Adriana

2015-01-01

Identify whether the degree of oral motor performance is related to the presence of teeth grinding and maximal bite force values in children with spastic cerebral palsy. Ninety-five spastic cerebral palsy children with and without teeth grinding, according to caregivers' reports, were submitted to a comprehensive oral motor performance evaluation during the feeding process using the Oral Motor Assessment Scale. Maximal bite force was measured using an electronic gnathodynamometer. The teeth grinding group (n = 42) was younger, used anticonvulsant drugs, and was more frequently classified within the subfunctional oral motor performance category. Teeth grinding subfunctional spastic cerebral palsy children presented lower values of maximal bite force. The functional groups showing the presence or absence of teeth grinding presented higher values of maximal bite force compared with the subfunctional groups. In spastic cerebral palsy children, teeth grinding is associated with the worse oral motor performance. © 2015 Special Care Dentistry Association and Wiley Periodicals, Inc.

Orthodontic treatment of a complex open-bite malocclusion with temporary anchorage devices: a case report.

PubMed

Waldman, Alexander B

2010-08-01

Orthodontic temporary anchorage devices provide a novel alternative to orthognathic surgery for the treatment of severe anterior open-bite malocclusions. These implantable devices provide skeletal anchorage for maxillary molar intrusion, allowing for mandibular autorotation and subsequent open-bite closure. This case demonstrates step-by-step treatment of a 41-year-old woman with a severe open-bite malocclusion. Detailed orthodontic mechanics are described at every stage of treatment.

Unilateral distalization of a maxillary molar with sliding mechanics: a case report.

PubMed

Keles, Ahmet

2002-06-01

A unilateral Class II relationship could arise due to early loss of an upper second deciduous molar on one side during the mixed dentition period. This would allow the mesial drift of the molars, which may block the eruption of the second premolar. A 15-year 8-month-old male patient presented with a Class II molar relationship on the right, and Class I canine and molar relationship on the left side. His E was extracted when he was 5 years old. The 54 were impacted and the 3 was ectopically positioned due to the space loss from the mesial migration of the 76. In addition 21 1 were in cross-bite. Skeletally he had Class III tendency with low MMPA. He presented with a straight profile and retruded upper lip. For maxillary molar distalization, a newly developed 'Keles Slider' was used. The appliance was composed of one premolar and two molar bands, and the anchorage unit was composed of a wide Nance button. 46 were connected to the Nance button and, therefore, included into the anchorage unit. The point of distal force application was close to the centre of resistance of the 6 and parallel to the occlusal plane. Ni-Ti coil springs were used and 200 g of distal force was applied. Seven months later the space required for eruption of the permanent premolars and canine was regained, and the anterior cross-bite corrected. The appliance was removed and final alignment of the teeth was achieved with fixed appliances. At the end of the second phase treatment Class I molar and canine relationship was achieved on the both sides, the anterior cross-bite was corrected, inter-incisal angle was improved, and ideal overbite and overjet relationship was achieved. The active treatment time was 27 months.

Fracture strength testing of crowns made of CAD/CAM composite resins.

PubMed

Okada, Ryota; Asakura, Masaki; Ando, Akihiro; Kumano, Hirokazu; Ban, Seiji; Kawai, Tatsushi; Takebe, Jun

2018-03-28

The purpose of this study was to ascertain whether computer aided design/computer aided manufacturing (CAD/CAM) composite resin crowns have sufficient strength to withstand the bite force of the molar teeth. The null hypothesis was that the fracture strength of CAD/CAM composite resin crowns is lower than the average maximum bite force of the molar tooth. The crowns, which shape is the right maxillary first molar, were fabricated using four CAD/CAM blanks made of composite resins (Block HC: HC, KZR-CAD HR: HR, KZR-CAD HR2: HR2, Avencia Block: AVE) and one CAD/CAM blank made of lithium disilicate glass-ceramic (IPS e.max CAD: IPS), which was used as a control. Fracture strength of fabricated crowns bonded to metal abutment and biaxial flexural strength of the materials were evaluated. The results of fracture strength test and biaxial flexural strength test showed different tendencies. The fracture strength of CAD/CAM composite resin crowns except HC ranged from 3.3kN to 3.9kN, and was similar to that of IPS (3.3kN). In contrast, biaxial flexural strength of CAD/CAM composite resins ranged from 175MPa to 247MPa, and was significantly lower than that of IPS (360MPa). All CAD/CAM composite resin crowns studied presented about 3-4 times higher fracture strength than the average maximum bite force of the molar tooth (700-900N), which result leads to the conclusion that CAD/CAM composite resin crowns would have sufficient strength to withstand the bite force of the molar teeth. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

[Prevalence of cross-bite in Mexican children].

PubMed

Ojeda León, S; De la Teja Angeles, E

1990-10-01

As observed, the problem of lining and accommodation of teeth in the child population is increasingly larger. This fact prompted the authors to attempt determining the prevalence of cross-bite in a sample of Mexican children. A total of 306 patients, aged between two and 17 and attending the Stomatology service of the National Institute of Pediatrics, were evaluated, from which all pertinent data regarding age, sex, molar-temporal relationship (terminal, rectus, distal, messial and exaggerated messial planes), permanent molar status (Angle I, II, III), cross-bite, type of dentition affected (primary, mixed or permanent), cross-bite classification (anterior, posterior or mixed), whether unilateral, bilateral, dental or skeletal, right or left, and number of teeth affected, were duly recorded. Out of 306 evaluated patients (160 males, 146 female), 112 evidenced cross-bite (36.6%), 56 of each sex; in 69.6% the teeth were anterior, in 17.8% they were posterior, and in 15.5% their position was mixed. Their average age was 8 years, and malocclusion was Angle class I. From this experience, it is to be concluded that early detection and correction of any dental occlusion abnormality will permit correcting defects in dentofacial development; it is thus necessary to ascertain the frequency of cross-bite.

Chin remodeling in a patient with bimaxillary protrusion and open bite by using mini-implants for temporary anchorage.

PubMed

Jiang, Chunmiao; Liu, Yinghong; Cheng, Qian; He, Wei; Fang, Shanbao; Lan, Tingting; Wang, Jun

2018-03-01

Patients with bimaxillary protrusion may have an unattractive profile with a retruded chin contour. Correction of the severely protrusive anterior alveolar bone and teeth combined with a moderate open bite without orthognathic surgery can be challenging. This case report describes the orthodontic treatment of a woman with severe bimaxillary protrusion and a moderate open bite. Excellent chin morphology and facial appearance were obtained with the extraction of 4 first premolars and 4 third molars, and total distalization of both arches with 4 mini-implants, one in each quadrant between the second premolar and the first molar. The total treatment time was 30 months. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Fiber Bragg Grating based bite force measurement.

PubMed

Umesh, Sharath; Padma, Srivani; Asokan, Sundarrajan; Srinivas, Talabattula

2016-09-06

The present study reports an in vivo, novel methodology for the dynamic measurement of the bite force generated by individual tooth using a Fiber Bragg Grating Bite Force Recorder (FBGBFR). Bite force is considered as one of the major indicators of the functional state of the masticatory system, which is dependent on the craniomandibular structure comprising functional components such as muscles of mastication, joints and teeth. The proposed FBGBFR is an intra-oral device, developed for the transduction of the bite force exerted at the occlusal surface, into strain variations on a base plate, which in turn is sensed by the FBG sensor bonded over it. The FBGBFR is calibrated against a Micro Universal Testing Machine (UTM) for 0-900N range and the resolution of the developed FBGBFR is found to be 0.54N. 36 volunteers (20 males and 16 females) performed the bite force measurement test at molar, premolar and incisor tooth on either side of the dental arch and the obtained results show clinically relevant bite forces varying from 176N to 635N. The bite forces obtained from the current study for a substantial sample size, show that the bite forces increases along the dental arch from the incisors towards the molars and are found to be higher in male than in female. The FBG sensor element utilized in FBGBFR is electrically passive, which makes it a safe in vivo intra-oral device. Hence the FBGBFR is viable to be employed in clinical studies on biomechanics of oral function. Copyright © 2016 Elsevier Ltd. All rights reserved.

A preliminary study to find a possible association between occlusal wear and maximum bite force in humans.

PubMed

Jain, Veena; Mathur, Vijay Prakash; Kumar, Abhishek

2013-01-01

The objective of the study was to investigate whether moderate-to-severe attrition is associated with maximum bite force in the first molar region. Maximum bite force in the first molar region was measured for a total of 60 subjects having moderate-to-severe attrition of occlusal surface (experimental group) using a specially-designed piezoelectric sensor based bite force measuring device. An equal number of age, gender, height and weight matched controls (control group) were also subjected to bite force measurement for comparison. The maximum bite force was found to be significantly lower (p < 0.05) in the experimental group [480.32 (153.40)] as compared to the controls [640.63 (148.90)]. While analyzing the possible etiology for occlusal wear mainly two reasons were elicited, i.e. history of parafunctional habits like use of known abrasive tooth powder (sub-group A) and Bruxism (sub-group B). However, there were many subjects in which no known definite etiological factors be attributed to occlusal wear (sub-group C). On analysing further with respect to the possibly correlated etiological factors with maximum bite force, no significant difference was found within the experimental sub-group. However, all three experimental sub-groups had significantly lower maximum bite force as compared to age, gender and BMI matched controls. A significantly lower maximum bite force was found to be associated with moderate-to-severe attrition as compared to subjects without attrition. However, no specific relation could be found between bite force and possible etiological factors like history of parafunctional habits, history of use of known abrasive tooth powder, etc.

Simple and Efficient Technique for Correction of Unilateral Scissor Bite Using Straight Wire.

PubMed

Dolas, Siddhesh Gajanan; Chitko, Shrikant Shrinivas; Kerudi, Veerendra Virupaxappa; Patil, Harshal Ashok; Bonde, Prasad Vasudeo

2016-03-01

Unilateral scissor bite is a relatively rare malocclusion. However, its correction is often difficult and a challenge for the clinician. This article presents simple and efficient technique for the correction of severe unilateral scissor bite in a 14 year old boy, using 0.020 S.S. A. J. Wilcock wire (premium plus) out of the spool, with minimal adjustments and placed in mandibular arch. After about six weeks time, good amount of correction was seen in the lower arch and the lower molar had been relieved of scissor bite.

Prevalence of Malocclusion among 6 to 10 Year old Nalgonda School Children

PubMed Central

Reddy, E Rajendra; Manjula, M; Sreelakshmi, N; Rani, S Thabitha; Aduri, Rajesh; Patil, B Dharamraj

2013-01-01

Background: To evaluate the prevalence of malocclusion among 6 to 10 year old children of Nalgonda District. Materials & Methods: A total of 3000 children were examined, out of which 2135 children (1009 boys and 1126 girls) who fulfilled the inclusion criteria were included. The selected sample was examined for Class I, Class II, Class III molar relationship, lower anterior crowding, cross bite (anterior and posterior), open bite, and pseudo class III [edge to edge bite] discrepancies after obtaining the written consent from the concerned school authorities. The collected data was tabulated and statistically analysed using chi-square test. Results: Among the selected sample, 648 (30.35%) children had minor tooth alignment discrepancies. Angle’s Class I molar relation with and without minor discrepancies was observed in 78.6%, Class II in 13.9%, Class III in 7.8% of the subjects surveyed. Lower anterior crowding in 11.8%, anterior cross bite in 4.5%, posterior cross bite in 3.75%, openbite in 3% and Pseudo class III [edge to edge] in 5.97% was noticed among the studied population. There was no statistical significant difference observed gender wise. Conclusion: In the current study, 52% of the studied population had malocclusion with a higher prevalence of Angle’s Class I molar relation with lower anterior crowding. How to cite this article: Reddy ER, Manjula M, Sreelakshmi N, Rani ST, Aduri R, Patil BD. Prevalence of Malocclusion among 6 to 10 Year old Nalgonda School Children. J Int Oral Health 2013; 5(6):49-54 . PMID:24453444

Extreme skeletal open bite correction with vertical elastics.

PubMed

Cruz-Escalante, Marco Antonio; Aliaga-Del Castillo, Aron; Soldevilla, Luciano; Janson, Guilherme; Yatabe, Marilia; Zuazola, Ricardo Voss

2017-11-01

Severe skeletal open bites may be ideally treated with a combined surgical-orthodontic approach. Alternatively, compensations may be planned to camouflage the malocclusion with orthodontics alone. This case report describes the treatment of an 18-year-old man who presented with a severe open bite involving the anterior and posterior teeth up to the first molars, increased vertical dimension, bilateral Class III molar relationship, bilateral posterior crossbite, dental midline deviation, and absence of the maxillary right canine and the mandibular left first premolar. A treatment plan including the extraction of the mandibular right first premolar and based on uprighting and vertical control of the posterior teeth, combined with extrusion of the anterior teeth using multiloop edgewise archwire mechanics and elastics was chosen. After 6 months of alignment and 2 months of multiloop edgewise archwire mechanics, the open bite was significantly reduced. After 24 months of treatment, anterior teeth extrusion, posterior teeth intrusion, and counterclockwise mandibular rotation were accomplished. Satisfactory improvement of the overbite, overjet, sagittal malocclusion, and facial appearance were achieved. The mechanics used in this clinical case demonstrated good and stable results for open-bite correction at the 2-year posttreatment follow-up.

Posterior Open Bite Due to Failure of Maxillary Molar Eruption.

PubMed

Yasumura, Toshihiko; Sueishi, Kenji

2016-01-01

Posterior open bite can cause problems with occlusion. It arises from systemic or local factors such as physical or functional interference, ankylosis, and failure of eruption. Primary failure of eruption (PFE) is a rare condition that is difficult to differentiate from ankylosis and requires complex treatment strategies. Here we report a 12-year-old girl who was referred to our hospital by her dentist for re-evaluation of eruption failure of the left maxillary secondary premolar and first and second molars with congenitally missing maxillary lateral teeth. The maxillary first molar was extracted for a therapeutic diagnosis. The left maxillary secondary premolar and second molar reacted well to subsequent orthodontic treatment. Auto-transplantation of the mandibular premolar to the maxil-lary arch was carried out to achieve optimal overjet, overbite, and occlusion. The active treatment period spanned 4 years and 1 month. Assessment of the patient's medical and dental history, prior trauma, and clinical conditions resulted in a therapeutic diagnosis of PFE. Satisfactory orthodontic treatment results were achieved.

Protraction of mandibular second and third molars assisted by partial corticision and miniscrew anchorage.

PubMed

Mimura, Hiroshi

2013-08-01

A woman, aged 47 years 6 months, with an anterior open bite and a left-shifted mandible was treated with a mandibular right first molar extraction and without orthognathic surgery. However, her mandibular second molar did not move mesially during treatment because of the dense lamina dura; therefore, corticision was applied only on the mesial aspect of the mandibular second molar, and a miniscrew was inserted simultaneously. Corticision was introduced as a supplemental dentoalveolar surgery in orthodontic therapy to achieve accelerated tooth movement with minimal surgical intervention. In this technique, a reinforced scalpel was used as a thin chisel to separate the interproximal cortices transmucosally without a flap. This technique was applied not to accelerate tooth movement, but to protract the mandibular molars. One miniscrew was inserted on the mesiobuccal side of the mandibular right molar for protraction and intrusion. In addition, 2 miniscrews were inserted in the buccal sides of the maxillary first and second molars and the palatal side of the maxillary first molar to intrude them for correction of the mandibular shift and the cant of the occlusal plane. Excellent occlusion and correction of the anterior open bite were achieved without surgery. At the 2-year follow-up examination, the patient had a good occlusion and showed good stability with no opening of the extraction space. A partial corticision is an effective option for facilitating movement of mandibular molars. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Simple and Efficient Technique for Correction of Unilateral Scissor Bite Using Straight Wire

PubMed Central

Dolas, Siddhesh Gajanan; Chitko, Shrikant Shrinivas; Kerudi, Veerendra Virupaxappa; Bonde, Prasad Vasudeo

2016-01-01

Unilateral scissor bite is a relatively rare malocclusion. However, its correction is often difficult and a challenge for the clinician. This article presents simple and efficient technique for the correction of severe unilateral scissor bite in a 14 year old boy, using 0.020 S.S. A. J. Wilcock wire (premium plus) out of the spool, with minimal adjustments and placed in mandibular arch. After about six weeks time, good amount of correction was seen in the lower arch and the lower molar had been relieved of scissor bite. PMID:27231682

Three-dimensional finite element analysis of the stress distribution pattern in a mandibular first molar tooth restored with five different restorative materials.

PubMed

D'souza, Kathleen Manuela; Aras, Meena Ajay

2017-01-01

Badly broken or structurally compromised posterior teeth are frequently associated with crown/root fracture. Numerous restorative materials have been used to fabricate indirect full-coverage restorations for such teeth. This study aims to evaluate and compare the effect of restorative materials on the stress distribution pattern in a mandibular first molar tooth, under varying loading conditions and to compare the stress distribution pattern in five commonly used indirect restorative materials. Five three-dimensional finite element models representing a mandibular first molar tooth restored with crowns of gold, porcelain fused to metal, composite (Artglass), alumina-based zirconia (In-Ceram Zirconia [ICZ]), and double-layered zirconia-based materials (zirconia core veneered with porcelain, Lava) were constructed, using a Finite Element Analysis Software (ANSYS version 10; ANSYS Inc., Canonsburg, PA, USA). Two loading conditions were applied, simulating maximum bite force of 600 N axially and normal masticatory bite force of 225 N axially and nonaxially. Both all-ceramic crowns allowed the least amount of stress distribution to the surrounding tooth structure. In maximum bite force-simulation test, alumina-based all-ceramic crown displayed the highest von Mises stresses (123.745 MPa). In the masticatory bite force-simulation test, both all-ceramic crowns (122.503-133.13 MPa) displayed the highest von Mises stresses. ICZ crown displayed the highest peak von Mises stress values under maximum and masticatory bite forces. ICZ and Lava crowns also allowed the least amount of stress distribution to the surrounding tooth structure, which is indicative of a favorable response of the underlying tooth structure to the overlying full-coverage indirect restorative material. These results suggest that ICZ and Lava crowns can be recommended for clinical use in cases of badly damaged teeth.

Chiropractic Manipulation Increases Maximal Bite Force in Healthy Individuals.

PubMed

Haavik, Heidi; Özyurt, Mustafa Görkem; Niazi, Imran Khan; Holt, Kelly; Nedergaard, Rasmus Wiberg; Yilmaz, Gizem; Türker, Kemal Sitki

2018-04-27

Recent research has shown that chiropractic spinal manipulation can alter central sensorimotor integration and motor cortical drive to human voluntary muscles of the upper and lower limb. The aim of this paper was to explore whether spinal manipulation could also influence maximal bite force. Twenty-eight people were divided into two groups of 14, one that received chiropractic care and one that received sham chiropractic care. All subjects were naive to chiropractic. Maximum bite force was assessed pre- and post-intervention and at 1-week follow up. Bite force in the chiropractic group increased compared to the control group ( p = 0.02) post-intervention and this between-group difference was also present at the 1-week follow-up ( p < 0.01). Bite force in the chiropractic group increased significantly by 11.0% (±18.6%) post-intervention ( p = 0.04) and remained increased by 13.0% (±12.9%, p = 0.04) at the 1 week follow up. Bite force did not change significantly in the control group immediately after the intervention (−2.3 ± 9.0%, p = 0.20), and decreased by 6.3% (±3.4%, p = 0.01) at the 1-week follow-up. These results indicate that chiropractic spinal manipulation can increase maximal bite force.

Case report: Management of severe posterior open bite due to primary failure of eruption.

PubMed

Mc Cafferty, J; Al Awadi, E; O'Connell, A C

2010-06-01

Primary failure of tooth eruption (PFE) is a rare condition affecting any or all posterior quadrants. Unilateral involvement of maxillary and mandibular quadrants causes a dramatic posterior open bite that requires complex management strategies. An 8 year-old boy attended the Dublin Dental School and Hospital regarding infra-occlusion of his right maxillary and mandibular primary molars. Both right first permanent molars had also failed to erupt. All permanent teeth were present radiographically. Facial appearance and soft tissues were normal and oral function was not affected. The patient had no significant medical history and his siblings had no similar dental abnormalities. The infra-occluded right first and second primary molars were extracted, and the right first permanent molars were surgically exposed. Eruption of the premolars and molars was monitored over the next 2 years. The premolars showed signs of eruption and continued root development. Exfoliation of the remaining primary teeth proceeded as usual. The right first permanent molars did not erupt and were subsequently extracted. Continued eruption of the canines and premolars reduced the inter-arch separation. A removable tongue shield appliance was suggested but declined by the patient. At age 13 years, orthodontic extrusion was used to further reduce the inter-dental distance between the canine and premolars. The reduction was from 5 mm to 1.5 mm between the right first premolars and from 10 mm to 5 mm between the right second premolars. Extrusion of the canine teeth was also attempted to improve the smile line. The canine extruded 1 mm to give a 2 mm overlap. There were no changes in centric occlusion and the midline was unaffected. In the 2 years since orthodontic treatment, the spaces have reopened slightly to 3 mm between first premolars and 6 mm between second premolars. The patient is now aged 16 years and is aware that an improved aesthetic smile line may be achieved by use of onlay restorations. In this unique case, a profound unilateral posterior open bite occurred due to primary failure of eruption of the maxillary and mandibular teeth on the affected side. Orthodontic therapy was used to modify the position of the permanent canines and premolars to reduce the posterior open bite.

The relationship between skull morphology, masticatory muscle force and cranial skeletal deformation during biting.

PubMed

Toro-Ibacache, Viviana; Zapata Muñoz, Víctor; O'Higgins, Paul

2016-01-01

The human skull is gracile when compared to many Middle Pleistocene hominins. It has been argued that it is less able to generate and withstand high masticatory forces, and that the morphology of the lower portion of the modern human face correlates most strongly with dietary characteristics. This study uses geometric morphometrics and finite element analysis (FEA) to assess the relationship between skull morphology, muscle force and cranial deformations arising from biting, which is relevant in understanding how skull morphology relates to mastication. The three-dimensional skull anatomies of 20 individuals were reconstructed from medical computed tomograms. Maximal contractile muscle forces were estimated from muscular anatomical cross-sectional areas (CSAs). Fifty-nine landmarks were used to represent skull morphology. A partial least squares analysis was performed to assess the association between skull shape and muscle force, and FEA was used to compare the deformation (strains) generated during incisor and molar bites in two individuals representing extremes of morphological variation in the sample. The results showed that only the proportion of total muscle CSA accounted for by the temporalis appears associated with skull morphology, albeit weekly. However, individuals with a large temporalis tend to possess a relatively wider face, a narrower, more vertically oriented maxilla and a lower positioning of the coronoid process. The FEAs showed that, despite differences in morphology, biting results in similar modes of deformation for both crania, but with localised lower magnitudes of strains arising in the individual with the narrowest, most vertically oriented maxilla. Our results suggest that the morphology of the maxilla modulates the transmission of forces generated during mastication to the rest of the cranium by deforming less in individuals with the ability to generate proportionately larger temporalis muscle forces. Copyright © 2015 Elsevier GmbH. All rights reserved.

Masticatory biomechanics in the rabbit: a multi-body dynamics analysis.

PubMed

Watson, Peter J; Gröning, Flora; Curtis, Neil; Fitton, Laura C; Herrel, Anthony; McCormack, Steven W; Fagan, Michael J

2014-10-06

Multi-body dynamics is a powerful engineering tool which is becoming increasingly popular for the simulation and analysis of skull biomechanics. This paper presents the first application of multi-body dynamics to analyse the biomechanics of the rabbit skull. A model has been constructed through the combination of manual dissection and three-dimensional imaging techniques (magnetic resonance imaging and micro-computed tomography). Individual muscles are represented with multiple layers, thus more accurately modelling muscle fibres with complex lines of action. Model validity was sought through comparing experimentally measured maximum incisor bite forces with those predicted by the model. Simulations of molar biting highlighted the ability of the masticatory system to alter recruitment of two muscle groups, in order to generate shearing or crushing movements. Molar shearing is capable of processing a food bolus in all three orthogonal directions, whereas molar crushing and incisor biting are predominately directed vertically. Simulations also show that the masticatory system is adapted to process foods through several cycles with low muscle activations, presumably in order to prevent rapidly fatiguing fast fibres during repeated chewing cycles. Our study demonstrates the usefulness of a validated multi-body dynamics model for investigating feeding biomechanics in the rabbit, and shows the potential for complementing and eventually reducing in vivo experiments.

Masticatory biomechanics in the rabbit: a multi-body dynamics analysis

PubMed Central

Watson, Peter J.; Gröning, Flora; Curtis, Neil; Fitton, Laura C.; Herrel, Anthony; McCormack, Steven W.; Fagan, Michael J.

2014-01-01

Multi-body dynamics is a powerful engineering tool which is becoming increasingly popular for the simulation and analysis of skull biomechanics. This paper presents the first application of multi-body dynamics to analyse the biomechanics of the rabbit skull. A model has been constructed through the combination of manual dissection and three-dimensional imaging techniques (magnetic resonance imaging and micro-computed tomography). Individual muscles are represented with multiple layers, thus more accurately modelling muscle fibres with complex lines of action. Model validity was sought through comparing experimentally measured maximum incisor bite forces with those predicted by the model. Simulations of molar biting highlighted the ability of the masticatory system to alter recruitment of two muscle groups, in order to generate shearing or crushing movements. Molar shearing is capable of processing a food bolus in all three orthogonal directions, whereas molar crushing and incisor biting are predominately directed vertically. Simulations also show that the masticatory system is adapted to process foods through several cycles with low muscle activations, presumably in order to prevent rapidly fatiguing fast fibres during repeated chewing cycles. Our study demonstrates the usefulness of a validated multi-body dynamics model for investigating feeding biomechanics in the rabbit, and shows the potential for complementing and eventually reducing in vivo experiments. PMID:25121650

Influence of maxillary posterior discrepancy on upper molar vertical position and facial vertical dimensions in subjects with or without skeletal open bite

PubMed Central

Aliaga-Del Castillo, Aron; Pérez-Vargas, Luis Fernando; Flores-Mir, Carlos

2016-01-01

Summary Objectives: To determine the influence of maxillary posterior discrepancy on upper molar vertical position and dentofacial vertical dimensions in individuals with or without skeletal open bite (SOB). Materials and methods: Pre-treatment lateral cephalograms of 139 young adults were examined. The sample was divided into eight groups categorized according to their sagittal and vertical skeletal facial growth pattern and maxillary posterior discrepancy (present or absent). Upper molar vertical position, overbite, lower anterior facial height and facial height ratio were measured. Independent t-test was performed to determine differences between the groups considering maxillary posterior discrepancy. Principal component analysis and MANCOVA test were also used. Results: No statistically significant differences were found comparing the molar vertical position according to maxillary posterior discrepancy for the SOB Class I group or the group with adequate overbite. Significant differences were found in SOB Class II and Class III groups. In addition, an increased molar vertical position was found in the group without posterior discrepancy. Limitations: Some variables closely related with the individual’s intrinsic craniofacial development that could influence the evaluated vertical measurements were not considered. Conclusions and implications: Overall maxillary posterior discrepancy does not appear to have a clear impact on upper molar vertical position or facial vertical dimensions. Only the SOB Class III group without posterior discrepancy had a significant increased upper molar vertical position. PMID:26385786

Influence of maxillary posterior discrepancy on upper molar vertical position and facial vertical dimensions in subjects with or without skeletal open bite.

PubMed

Arriola-Guillén, Luis Ernesto; Aliaga-Del Castillo, Aron; Pérez-Vargas, Luis Fernando; Flores-Mir, Carlos

2016-06-01

To determine the influence of maxillary posterior discrepancy on upper molar vertical position and dentofacial vertical dimensions in individuals with or without skeletal open bite (SOB). Pre-treatment lateral cephalograms of 139 young adults were examined. The sample was divided into eight groups categorized according to their sagittal and vertical skeletal facial growth pattern and maxillary posterior discrepancy (present or absent). Upper molar vertical position, overbite, lower anterior facial height and facial height ratio were measured. Independent t-test was performed to determine differences between the groups considering maxillary posterior discrepancy. Principal component analysis and MANCOVA test were also used. No statistically significant differences were found comparing the molar vertical position according to maxillary posterior discrepancy for the SOB Class I group or the group with adequate overbite. Significant differences were found in SOB Class II and Class III groups. In addition, an increased molar vertical position was found in the group without posterior discrepancy. Some variables closely related with the individual's intrinsic craniofacial development that could influence the evaluated vertical measurements were not considered. Overall maxillary posterior discrepancy does not appear to have a clear impact on upper molar vertical position or facial vertical dimensions. Only the SOB Class III group without posterior discrepancy had a significant increased upper molar vertical position. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Outcomes and stability in patients with anterior open bite and long anterior face height treated with temporary anchorage devices and a maxillary intrusion splint

PubMed Central

Scheffler, Nicole R.; Proffit, William R.; Phillips, Ceib

2015-01-01

Introduction Temporary skeletal anchorage devices now offer the possibility of closing anterior open bites and decreasing anterior face height by intruding maxillary posterior teeth, but data for treatment outcomes are lacking. This article presents outcomes and posttreatment changes for consecutive patients treated with a standardized technique. Methods The sample included 33 consecutive patients who had intrusion of maxillary posterior teeth with a maxillary occlusal splint and nickel-titanium coil springs to temporary anchorage devices in the zygomatic buttress area, buccal and apical to the maxillary molars. Of this group, 30 had adequate cephalograms available for the period of treatment, 27 had cephalograms including 1-year posttreatment, and 25 had cephalograms from 2 years or longer. Results During splint therapy, the mean molar intrusion was 2.3 mm. The mean decrease in anterior face height was 1.6 mm, less than expected because of a 0.6-mm mean eruption of the mandibular molars. During the postintrusion orthodontics, the mean change in maxillary molar position was a 0.2-mm extrusion, and there was a mean 0.5-mm increase in face height. Positive overbite was maintained in all patients, with a slight elongation (<2 mm) of the incisors contributing to this. During the 1 year of posttreatment retention, the mean changes were a further eruption of 0.5 mm of the maxillary molars, whereas the mandibular molars intruded by 0.6 mm, and there was a small decrease in anterior face height. Changes beyond 1 year posttreatment were small and attributable to growth rather than relapse in tooth positions. Conclusions Intrusion of the maxillary posterior teeth can give satisfactory correction of moderately severe anterior open bites, but 0.5 to 1.5 mm of reeruption of these teeth is likely to occur. Controlling the vertical position of the mandibular molars so that they do not erupt as the maxillary teeth are intruded is important in obtaining a decrease in face height. PMID:25439210

Biting mechanics and niche separation in a specialized clade of primate seed predators

PubMed Central

Luk, Theodora H. Y.; Perry, Jonathan M. G.; Neaux, Dimitri; Wroe, Stephen

2018-01-01

We analyzed feeding biomechanics in pitheciine monkeys (Pithecia, Chiropotes, Cacajao), a clade that specializes on hard-husked unripe fruit (sclerocarpy) and resistant seeds (seed predation). We tested the hypothesis that pitheciine crania are well-suited to generate and withstand forceful canine and molar biting, with the prediction that they generate bite forces more efficiently and better resist masticatory strains than the closely-related Callicebus, which does not specialize on unripe fruits and/or seeds. We also tested the hypothesis that Callicebus-Pithecia-Chiropotes-Cacajao represent a morphocline of increasing sclerocarpic specialization with respect to biting leverage and craniofacial strength, consistent with anterior dental morphology. We found that pitheciines have higher biting leverage than Callicebus and are generally more resistant to masticatory strain. However, Cacajao was found to experience high strain magnitudes in some facial regions. We therefore found limited support for the morphocline hypothesis, at least with respect to the mechanical performance metrics examined here. Biting leverage in Cacajao was nearly identical (or slightly less than) in Chiropotes and strain magnitudes during canine biting were more likely to follow a Cacajao-Chiropotes-Pithecia trend of increasing strength, in contrast to the proposed morphocline. These results could indicate that bite force efficiency and derived anterior teeth were selected for in pitheciines at the expense of increased strain magnitudes. However, our results for Cacajao potentially reflect reduced feeding competition offered by allopatry with other pitheciines, which allows Cacajao species to choose from a wider variety of fruits at various stages of ripeness, leading to reduction in the selection for robust facial features. We also found that feeding biomechanics in sympatric Pithecia and Chiropotes are consistent with data on food structural properties and observations of dietary niche separation, with the former being well-suited for the regular molar crushing of hard seeds and the latter better adapted for breaching hard fruits. PMID:29324822

Vertical bone growth following autotransplantation of the developing maxillary third molar to replace a retained mandibular permanent molar: a case report.

PubMed

Plakwicz, Paweł; Czochrowska, Ewa Monika; Milczarek, Anna; Zadurska, Malgorzata

2014-01-01

A retained permanent mandibular first molar caused arrested development and a defect of the alveolar bone in a 16-year-old girl. Extraction of the ankylosed tooth was immediately followed by autotransplantation of the developing maxillary third molar. At the 3-year follow-up examination the interproximal bone level at the autotransplanted molar was equal to that of the neighboring teeth. Cone beam computed tomography showed bone at the labial aspect of the transplant. The eruption of the autotransplanted tooth stimulated vertical alveolar bone development and repaired the bone defect. Additionally, there was closure of the posterior open bite that was initially present at the ankylosed molar site.

Finite element stress analysis of stainless steel crowns.

PubMed

Prabhakar, Attiguppe R; Yavagal, Chandrashekar M; Chakraborty, Amrita; Sugandhan, S

2015-01-01

Though stainless steel crowns (SSCs) have often been stated as the best restorative modality, there are limited studies demonstrating its efficacy in restoring the functional integrity of the primary dentition. Hence has arisen, the necessity to establish the supremacy of SSCs. Evaluation of the efficacy of SSC to with stand compressive (0°), shearing (90°), and torsional (45°) stress when used as a restorative material. The study design employed four finite element models, each with differing amounts of tooth structure, which were exported to ANSYS software and subjected to an average simulated bite force of 245N. Four maxillary deciduous primary molars restored with SSCs (3M ESPE) were subjected to spiral computed tomography (CT) in order to obtain three-dimensional (3D) images, which were then converted into finite element models. They were each subjected to forces along the long axis of the tooth and at 45°and 90°. The maximal equivalent von Mises stress was demonstrated in the SSCs of all the models with only a minimal amount observed in the underlying dentine. In all situations, the maximal equivalent von Mises stress was well below the ultimate tensile strength values of stainless steel and dentine. Even at maximal physiologic masticatory force levels, a grossly destructed tooth restored with SSC is able to resist deformation.

[Maximal isometric bite force and sports. Preliminary study].

PubMed

Sannajust, J P; Thiery, C; Poumarat, G; Vanneuville, G; Barthélémy, I; Mondie, J M

2002-06-01

The evaluation of the bite forces coupled with EMG activity of masseter muscles allows to point out temporo-mandibular joint disorders. The intense practice of sports induces stress which may affect the mandibular statics, due to an hyperfunction of the elevator masticatory muscles, especially the masseter muscles. This concept has led us to compare the maximum isometric bite forces of sedentary and physically trained subjects. The aim of this experimentation is to study the maximum isometric bite forces of the premolars, with a force transducer, for two groups of physically trained and sedentary volunteers (25 subjects), with distinction between male and female subjects. Subjects with normal denture and no temporo-mandibular joint disorder were retained. EMG and force recording were synchronized and recorded during 10 seconds of maximal contraction. The male subjects developed a maximal bite-force significantly higher (p < 0.05) compared to the female subjects. There is no significant difference between subjects practising a sport (at least 6 hours a week) and sedentary ones. The evolution of force during the contraction is different between sexes. EMG activity allowed to control that subjects developed a maximal force and an increase in muscular fatigability of physically active females compared to sedentary ones was noticed. The difference of maximal force between men and women is similar to the one found for the locomotor muscles. The analysis of the evolution of the force according to the contraction duration, might be linked to a different distribution of muscular fibers according to the sex. The practice of a sport might increase the fatigability of the masseter muscles and might be a factor inducing a muscular imbalance of the mandibular posture. But the relatively low number of subjects and the absence of well defined distinctions between different kinds of sport limit our conclusions.

Analysis of factors associated with cracked teeth.

PubMed

Seo, Deog-Gyu; Yi, Young-Ah; Shin, Su-Jung; Park, Jeong-Won

2012-03-01

The purpose of this study was to analyze the characteristics, distribution, and associated factors of longitudinal fractured teeth according to the well-defined criteria of the American Association of Endodontists (AAE). One hundred seven teeth with longitudinal fracture from 103 patients were diagnosed and analyzed. The patients' signs, symptoms, age, and sex were noted as well as the tooth number, dental arch, filling materials, size/classification of restoration, crack direction, pulp vitality, whether the patient had undergone endodontic treatment, bite test results, percussion test results, wear facet, and periodontal pocket depth. Eighty-seven teeth were diagnosed with a cracked tooth (81.3%), 14 were diagnosed with vertical root fracture (VRF, 13.1%), 4 had a split tooth (3.7%), and 2 had a fractured cusp (1.9%); 82.2% showed a sensitive reaction on the bite test. Longitudinal tooth fractures were observed most frequently in patient in their 40s. The upper first molar (28.0%) was most frequently cracked, followed by the lower first molar (25.2%), the lower second molar (20.6%), and the upper second molar (16.8%). Most longitudinal tooth fractures (72.0%) occurred mainly in restored teeth, whereas only 28.0% were found in intact teeth. Compared with resin (4.7%) or porcelain (0.9%), the use of nonbonded inlay restoration materials such as gold (20.5%) or amalgam (18.7%) increased the occurrence of longitudinal tooth fractures. Out of 107 of longitudinal fractured teeth, 33 (30.8%) were treated endodontically and 74 (69.2%) were not. VRF was associated with endodontic treatment. The bite test is most reliable for reproducing symptoms. The combined use of various examination methods is recommended for detecting cracks and minutely inspecting all directions of a tooth. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Changes in maximum bite force related to extension of the head.

PubMed

Hellsing, E; Hagberg, C

1990-05-01

The maximum bite force and position of the hyoid bone during natural and extended head posture were studied in 15 adults. All participants had normal occlusions and full dentitions. In addition, there were no signs or symptoms of craniomandibular disorders. The bite force was measured with a bite force sensor placed between the first molars. Six registrations of gradually increasing bite force up to a maximum were made with randomized natural and extended head postures. With one exception, the mean maximum bite force value was found to be higher for every subject with extended head posture compared to natural head posture. The sample mean was 271.6 Newton in natural head posture and 321.5 Newton with 20 degrees extension. With changed head posture, the cephalometric measurements pointed towards a changed position of the hyoid bone in relation to the mandible and pharyngeal airway. The cephalometric changes in the position of the hyoid bone could be due to a changed interplay between the elevator and depressor muscle groups. This was one factor which could have influenced the registered maximum bite force.

Open bite: diagnosis, treatment and stability.

PubMed

Matsumoto, Mírian Aiko Nakane; Romano, Fábio Lourenço; Ferreira, José Tarcísio Lima; Valério, Rodrigo Alexandre

2012-01-01

Open bite has fascinated Orthodontics due to the difficulties regarding its treatment and maintenance of results. This anomaly has distinct characteristics that, in addition to the complexity of multiple etiological factors, have aesthetic and functional consequences. Within this etiological context, several types of mechanics have been used in open bite treatment, such as palatal crib, orthopedic forces, occlusal adjustment, orthodontic camouflage with or without extraction, orthodontic intervention using mini-implants or mini-plates, and even orthognathic surgery. An accurate diagnosis and etiological determination are always the best guides to establish the objectives and the ideal treatment plan for such a malocclusion. This report describes two cases of open bite. At the end of the treatment, both patients had their canines and molars in Class I occlusion, normal overjet and overbite, and stability during the posttreatment period.

Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics

PubMed Central

Bates, K. T.; Falkingham, P. L.

2012-01-01

Bite mechanics and feeding behaviour in Tyrannosaurus rex are controversial. Some contend that a modest bite mechanically limited T. rex to scavenging, while others argue that high bite forces facilitated a predatory mode of life. We use dynamic musculoskeletal models to simulate maximal biting in T. rex. Models predict that adult T. rex generated sustained bite forces of 35 000–57 000 N at a single posterior tooth, by far the highest bite forces estimated for any terrestrial animal. Scaling analyses suggest that adult T. rex had a strong bite for its body size, and that bite performance increased allometrically during ontogeny. Positive allometry in bite performance during growth may have facilitated an ontogenetic change in feeding behaviour in T. rex, associated with an expansion of prey range in adults to include the largest contemporaneous animals. PMID:22378742

Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics.

PubMed

Bates, K T; Falkingham, P L

2012-08-23

Bite mechanics and feeding behaviour in Tyrannosaurus rex are controversial. Some contend that a modest bite mechanically limited T. rex to scavenging, while others argue that high bite forces facilitated a predatory mode of life. We use dynamic musculoskeletal models to simulate maximal biting in T. rex. Models predict that adult T. rex generated sustained bite forces of 35 000-57 000 N at a single posterior tooth, by far the highest bite forces estimated for any terrestrial animal. Scaling analyses suggest that adult T. rex had a strong bite for its body size, and that bite performance increased allometrically during ontogeny. Positive allometry in bite performance during growth may have facilitated an ontogenetic change in feeding behaviour in T. rex, associated with an expansion of prey range in adults to include the largest contemporaneous animals.

The Effect of Varying Jaw-elevator Muscle Forces on a Finite Element Model of a Human Cranium.

PubMed

Toro-Ibacache, Viviana; O'Higgins, Paul

2016-07-01

Finite element analyses simulating masticatory system loading are increasingly undertaken in primates, hominin fossils and modern humans. Simplifications of models and loadcases are often required given the limits of data and technology. One such area of uncertainty concerns the forces applied to cranial models and their sensitivity to variations in these forces. We assessed the effect of varying force magnitudes among jaw-elevator muscles applied to a finite element model of a human cranium. The model was loaded to simulate incisor and molar bites using different combinations of muscle forces. Symmetric, asymmetric, homogeneous, and heterogeneous muscle activations were simulated by scaling maximal forces. The effects were compared with respect to strain distribution (i.e., modes of deformation) and magnitudes; bite forces and temporomandibular joint (TMJ) reaction forces. Predicted modes of deformation, strain magnitudes and bite forces were directly proportional to total applied muscle force and relatively insensitive to the degree of heterogeneity of muscle activation. However, TMJ reaction forces and mandibular fossa strains decrease and increase on the balancing and working sides according to the degree of asymmetry of loading. These results indicate that when modes, rather than magnitudes, of facial deformation are of interest, errors in applied muscle forces have limited effects. However the degree of asymmetric loading does impact on TMJ reaction forces and mandibular fossa strains. These findings are of particular interest in relation to studies of skeletal and fossil material, where muscle data are not available and estimation of muscle forces from skeletal proxies is prone to error. Anat Rec, 299:828-839, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Masticatory loadings and cranial deformation in Macaca fascicularis: a finite element analysis sensitivity study.

PubMed

Fitton, L C; Shi, J F; Fagan, M J; O'Higgins, P

2012-07-01

Biomechanical analyses are commonly conducted to investigate how craniofacial form relates to function, particularly in relation to dietary adaptations. However, in the absence of corresponding muscle activation patterns, incomplete muscle data recorded experimentally for different individuals during different feeding tasks are frequently substituted. This study uses finite element analysis (FEA) to examine the sensitivity of the mechanical response of a Macaca fascicularis cranium to varying muscle activation patterns predicted via multibody dynamic analysis. Relative to the effects of varying bite location, the consequences of simulated variations in muscle activation patterns and of the inclusion/exclusion of whole muscle groups were investigated. The resulting cranial deformations were compared using two approaches; strain maps and geometric morphometric analyses. The results indicate that, with bite force magnitude controlled, the variations among the mechanical responses of the cranium to bite location far outweigh those observed as a consequence of varying muscle activations. However, zygomatic deformation was an exception, with the activation levels of superficial masseter being most influential in this regard. The anterior portion of temporalis deforms the cranial vault, but the remaining muscles have less profound effects. This study for the first time systematically quantifies the sensitivity of an FEA model of a primate skull to widely varying masticatory muscle activations and finds that, with the exception of the zygomatic arch, reasonable variants of muscle loading for a second molar bite have considerably less effect on cranial deformation and the resulting strain map than does varying molar bite point. The implication is that FEA models of biting crania will generally produce acceptable estimates of deformation under load as long as muscle activations and forces are reasonably approximated. In any one FEA study, the biological significance of the error in applied muscle forces is best judged against the magnitude of the effect that is being investigated. © 2012 The Authors. Journal of Anatomy © 2012 Anatomical Society.

Masticatory loadings and cranial deformation in Macaca fascicularis: a finite element analysis sensitivity study

PubMed Central

Fitton, L C; Shi, J F; Fagan, M J; O’Higgins, P

2012-01-01

Biomechanical analyses are commonly conducted to investigate how craniofacial form relates to function, particularly in relation to dietary adaptations. However, in the absence of corresponding muscle activation patterns, incomplete muscle data recorded experimentally for different individuals during different feeding tasks are frequently substituted. This study uses finite element analysis (FEA) to examine the sensitivity of the mechanical response of a Macaca fascicularis cranium to varying muscle activation patterns predicted via multibody dynamic analysis. Relative to the effects of varying bite location, the consequences of simulated variations in muscle activation patterns and of the inclusion/exclusion of whole muscle groups were investigated. The resulting cranial deformations were compared using two approaches; strain maps and geometric morphometric analyses. The results indicate that, with bite force magnitude controlled, the variations among the mechanical responses of the cranium to bite location far outweigh those observed as a consequence of varying muscle activations. However, zygomatic deformation was an exception, with the activation levels of superficial masseter being most influential in this regard. The anterior portion of temporalis deforms the cranial vault, but the remaining muscles have less profound effects. This study for the first time systematically quantifies the sensitivity of an FEA model of a primate skull to widely varying masticatory muscle activations and finds that, with the exception of the zygomatic arch, reasonable variants of muscle loading for a second molar bite have considerably less effect on cranial deformation and the resulting strain map than does varying molar bite point. The implication is that FEA models of biting crania will generally produce acceptable estimates of deformation under load as long as muscle activations and forces are reasonably approximated. In any one FEA study, the biological significance of the error in applied muscle forces is best judged against the magnitude of the effect that is being investigated. PMID:22690885

Corticotomy-assisted orthodontic camouflage in a class III adult patient with a severe transverse discrepancy.

PubMed

Gracco, Antonio; Finotti, Marco; Bruno, Giovanni; de Stefani, Alberto

2018-04-06

A 25-year-old man presented with a maxillary transverse discrepancy, posterior cross bite, anterior open bite, molar and canine class III. Treatment included a corticotomy in the upper lateral and posterior teeth, a palatal expansor and a sectional archwire to assist the expansion. The following treatment phase included bonding with Incognito System lingual appliance, interproximal reduction to solve the crowding and bite blocks to control the verticality. Two months after the bonding intermaxillary class III elastics were used to solve the sagittal discrepancy and eight months after the bonding vertical elastics were used in order to solve the anterior open bite until the end of the treatment. A Boston splint was applied for the upper arch, an essix splint was applied for the lower arch. The patient compliance was an essential aspect in the success of the orthodontic treatment. Copyright © 2018. Published by Elsevier Masson SAS.

Maxillary molar distalization with first class appliance

PubMed Central

Ramesh, Namitha; Palukunnu, Biswas; Ravindran, Nidhi; Nair, Preeti P

2014-01-01

Non-extraction treatment has gained popularity for corrections of mild-to-moderate class II malocclusion over the past few decades. The distalization of maxillary molars is of significant value for treatment of cases with minimal arch discrepancy and mild class II molar relation associated with a normal mandibular arch and acceptable profile. This paper describes our experience with a 16-year-old female patient who reported with irregularly placed upper front teeth and unpleasant smile. The patient was diagnosed to have angles class II malocclusion with moderate maxillary anterior crowding, deep bite of 4 mm on a skeletal class II base with an orthognathic maxilla and retrognathic mandible and normal growth pattern. She presented an ideal profile and so molar distalization was planned with the first-class appliance. Molars were distalised by 8 mm on the right and left quadrants and class I molar relation achieved within 4 months. The space gained was utilised effectively to align the arch and establish a class I molar and canine relation. PMID:24577171

Maximal bite force, facial morphology and sucking habits in young children with functional posterior crossbite.

PubMed

Castelo, Paula Midori; Gavião, Maria Beatriz Duarte; Pereira, Luciano José; Bonjardim, Leonardo Rigoldi

2010-01-01

The maintenance of normal conditions of the masticatory function is determinant for the correct growth and development of its structures. Thus, the aims of this study were to evaluate the influence of sucking habits on the presence of crossbite and its relationship with maximal bite force, facial morphology and body variables in 67 children of both genders (3.5-7 years) with primary or early mixed dentition. The children were divided in four groups: primary-normocclusion (PN, n=19), primary-crossbite (PC, n=19), mixed-normocclusion (MN, n=13), and mixed-crossbite (MC, n=16). Bite force was measured with a pressurized tube, and facial morphology was determined by standardized frontal photographs: AFH (anterior face height) and BFW (bizygomatic facial width). It was observed that MC group showed lower bite force than MN, and AFH/BFW was significantly smaller in PN than PC (t-test). Weight and height were only significantly correlated with bite force in PC group (Pearson's correlation test). In the primary dentition, AFH/BFW and breast-feeding (at least six months) were positive and negatively associated with crossbite, respectively (multiple logistic regression). In the mixed dentition, breast-feeding and bite force showed negative associations with crossbite (univariate regression), while nonnutritive sucking (up to 3 years) associated significantly with crossbite in all groups (multiple logistic regression). In the studied sample, sucking habits played an important role in the etiology of crossbite, which was associated with lower bite force and long-face tendency.

Orthodontic treatment of an anterior openbite with the aid of corticotomy procedure: Case report

PubMed Central

Aljhani, Ali S.; Aldrees, Abdullah M.

2010-01-01

This case report illustrates the orthodontic treatment combined with the corticotomy technique in an adult patient to accelerate tooth movement and shorten the treatment time. The patient was a 22-year-old woman with an anterior open bite and flared and spaced upper and lower incisors. First, fixed orthodontic appliances (bidimensional edgewise brackets) were bonded, and a week later buccal and lingual corticotomy with alveolar augmentation procedure in the maxillary arch from the first molar to the contralateral first molar, and from canine to canine in the mandibular arch was performed. Orthodontic therapy proceeded with frequent activation of the appliances to retract the incisors every 2 weeks. The total treatment time was 5 months and no adverse effects were observed at the end of active treatment. The addition of the decortication procedure to the conventional orthodontic therapy decreased the duration of treatment significantly. Successful closure of the anterior open bite with adequate overbite and interdigitation of the teeth were achieved. PMID:24151417

Distalization of maxillary arch and correction of Class II with mini-implants: A report of two cases

PubMed Central

Tekale, Pawankumar Dnyandeo; Vakil, Ketan K.; Vakil, Jeegar K.; Gore, Ketan A.

2015-01-01

This article reports the successful use of mini-screws in the maxilla to treat two patients of age 21-year and 17-year-old girls. Both the patients had a skeletal Class II malocclusion with protrusive maxillary teeth and angels Class II mal-occlusion. Temporary anchorage devices (TADs) in the posterior dental region between maxillary second premolar and maxillary first molar teeth on both sides were used as anchorage for the retraction and intrusion of her maxillary anterior teeth. Those appliances, combined with a compensatory curved maxillary archwire, eliminated spacing, deep bite, forwardly placed and proclined upper front teeth and the protrusive profile, corrected the molar relationship from Class II to Class I. With no extra TADs in the anterior region for intrusion, the treatment was workable and simple. The patient received a satisfactory occlusion and an attractive smile. This technique requires minimal compliance and is particularly useful for correcting Class II patients with protrusive maxillary front teeth and dental deep bite. PMID:26097360

Orthodontic treatment of an anterior openbite with the aid of corticotomy procedure: Case report.

PubMed

Aljhani, Ali S; Aldrees, Abdullah M

2011-04-01

This case report illustrates the orthodontic treatment combined with the corticotomy technique in an adult patient to accelerate tooth movement and shorten the treatment time. The patient was a 22-year-old woman with an anterior open bite and flared and spaced upper and lower incisors. First, fixed orthodontic appliances (bidimensional edgewise brackets) were bonded, and a week later buccal and lingual corticotomy with alveolar augmentation procedure in the maxillary arch from the first molar to the contralateral first molar, and from canine to canine in the mandibular arch was performed. Orthodontic therapy proceeded with frequent activation of the appliances to retract the incisors every 2 weeks. The total treatment time was 5 months and no adverse effects were observed at the end of active treatment. The addition of the decortication procedure to the conventional orthodontic therapy decreased the duration of treatment significantly. Successful closure of the anterior open bite with adequate overbite and interdigitation of the teeth were achieved.

Effect of gender, facial dimensions, body mass index and type of functional occlusion on bite force.

PubMed

Koç, Duygu; Doğan, Arife; Bek, Bülent

2011-01-01

Some factors such as gender, age, craniofacial morphology, body structure, occlusal contact patterns may affect the maximum bite force. Thus, the purposes of this study were to determine the mean maximum bite force in individuals with normal occlusion, and to examine the effect of gender, facial dimensions, body mass index (BMI), type of functional occlusion (canine guidance and group function occlusion) and balancing side interferences on it. Thirty-four individuals aged 19-20 years-old were selected for this study. Maximum bite force was measured with strain-gauge transducers at first molar region. Facial dimensions were defined by standardized frontal photographs as follows: anterior total facial height (ATFH), bizygomathic facial width (BFW) and intergonial width (IGW). BMI was calculated using the equation weight/height². The type of functional occlusion and the balancing side interferences of the subjects were identified by clinical examination. Bite force was found to be significantly higher in men than women (p<0.05). While there was a negative correlation between the bite force and ATFH/BFW, ATFH/IGW ratios in men (p<0.05), women did not show any statistically significant correlation (p>0.05). BMI and bite force correlation was not statistically significant (p>0.05). The average bite force did not differ in subjects with canine guidance or group function occlusion and in the presence of balancing side interferences (p>0.05). Data suggest that bite force is affected by gender. However, BMI, type of functional occlusion and the presence of balancing side interferences did not exert a meaningful influence on bite force. In addition, transverse facial dimensions showed correlation with bite force in only men.

Maximal bite force, facial morphology and sucking habits in young children with functional posterior crossbite

PubMed Central

CASTELO, Paula Midori; GAVIÃO, Maria Beatriz Duarte; PEREIRA, Luciano José; BONJARDIM, Leonardo Rigoldi

2010-01-01

Objective The maintenance of normal conditions of the masticatory function is determinant for the correct growth and development of its structures. Thus, the aims of this study were to evaluate the influence of sucking habits on the presence of crossbite and its relationship with maximal bite force, facial morphology and body variables in 67 children of both genders (3.5-7 years) with primary or early mixed dentition. Material and methods The children were divided in four groups: primary-normocclusion (PN, n=19), primary-crossbite (PC, n=19), mixed-normocclusion (MN, n=13), and mixed-crossbite (MC, n=16). Bite force was measured with a pressurized tube, and facial morphology was determined by standardized frontal photographs: AFH (anterior face height) and BFW (bizygomatic facial width). Results It was observed that MC group showed lower bite force than MN, and AFH/ BFW was significantly smaller in PN than PC (t-test). Weight and height were only significantly correlated with bite force in PC group (Pearson’s correlation test). In the primary dentition, AFH/BFW and breast-feeding (at least six months) were positive and negatively associated with crossbite, respectively (multiple logistic regression). In the mixed dentition, breastfeeding and bite force showed negative associations with crossbite (univariate regression), while nonnutritive sucking (up to 3 years) associated significantly with crossbite in all groups (multiple logistic regression). Conclusions In the studied sample, sucking habits played an important role in the etiology of crossbite, which was associated with lower bite force and long-face tendency. PMID:20485925

Treatment of hyperdivergent growth pattern and anterior open bite with posterior metallic bite planes.

PubMed

Ciavarella, Domenico; Lo Russo, Lucio; Nichelini, Jeffrey; Mastrovincenzo, Mario; Barbato, Ersilia; Laurenziello, Michele; Montaruli, Graziano; Lo Muzio, Lorenzo

2017-12-01

In the present paper, the authors analyze the effect of the "Swallowing Occlusal Contact Intercept Appliance" (SOCIA) in treatment of children with hyperdivergent Class II malocclusion. This functional appliance has no intra-oral anchorage, but induces a continuous periodontal, muscular, and articular stimulation. Twenty-six patients with hyperdivergent growth and class II malocclusion were selected and treated with SOCIA appliance. Cephalometric analysis was performed before treatment (T1) and immediately after the treatment (T2). After 24 months treatment authors observed a modification of maxillary growth with a reduction of the divergence with an increase of the posterior facial height, a modification of condylar inclination and forward position of the a hyoid. No modifications was observed about the ANB angle. After treatment the open bite was resolved with a reduction of the inclination of the upper incisors. SOCIA is a reliable functional appliance in growing age patients with a hyperdivergent pattern growth, anterior open bite and class II molar malocclusion.

The jaw is a second-class lever in Pedetes capensis (Rodentia: Pedetidae)

PubMed Central

2017-01-01

The mammalian jaw is often modelled as a third-class lever for the purposes of biomechanical analyses, owing to the position of the resultant muscle force between the jaw joint and the teeth. However, it has been proposed that in some rodents the jaws operate as a second-class lever during distal molar bites, owing to the rostral position of the masticatory musculature. In particular, the infraorbital portion of the zygomatico-mandibularis (IOZM) has been suggested to be of major importance in converting the masticatory system from a third-class to a second-class lever. The presence of the IOZM is diagnostic of the hystricomorph rodents, and is particularly well-developed in Pedetes capensis, the South African springhare. In this study, finite element analysis (FEA) was used to assess the lever mechanics of the springhare masticatory system, and to determine the function of the IOZM. An FE model of the skull of P. capensis was constructed and loaded with all masticatory muscles, and then solved for biting at each tooth in turn. Further load cases were created in which each masticatory muscle was removed in turn. The analyses showed that the mechanical advantage of the springhare jaws was above one at all molar bites and very close to one during the premolar bite. Removing the IOZM or masseter caused a drop in mechanical advantage at all bites, but affected strain patterns and cranial deformation very little. Removing the ZM had only a small effect on mechanical advantage, but produced a substantial reduction in strain and deformation across the skull. It was concluded that the masticatory system of P. capensis acts as a second class lever during bites along almost the entire cheek tooth row. The IOZM is clearly a major contributor to this effect, but the masseter also has a part to play. The benefit of the IOZM is that it adds force without substantially contributing to strain or deformation of the skull. This may help explain why the hystricomorphous morphology has evolved multiple times independently within Rodentia. PMID:28875081

Sleep endoscopy with simulation bite for prediction of oral appliance treatment outcome.

PubMed

Vroegop, Anneclaire V M T; Vanderveken, Olivier M; Dieltjens, Marijke; Wouters, Kristien; Saldien, Vera; Braem, Marc J; Van de Heyning, Paul H

2013-06-01

The aim of this study was to assess the value of drug-induced sleep endoscopy (DISE) using a custom-made simulation bite in maximal comfortable protrusion (MCP) of the mandible, in the prediction of treatment outcome for obstructive sleep apnea (OSA) with a mandibular advancement device (MAD). Two hundred patients (74% male; age 46 ± 9 years; apnea-hypopnea index [AHI] 19 ± 13 h(-1) sleep; body mass index [BMI] 27 ± 4 kg m(-2) ) with sleep-disordered breathing underwent DISE with a simulation bite in MCP. One hundred and thirty-five patients with an established diagnosis of OSA commenced MAD treatment. The associations between the findings during DISE with simulation bite and treatment outcome were evaluated. Treatment response was defined as a reduction in AHI following MAD treatment of ≥ 50% compared to baseline. Overall MAD treatment response in the studied population was 69%. The results of this study demonstrated a statistically significant association between a positive effect of the simulation bite on the upper airway patency during DISE and treatment response with MAD (P < 0.01). The results of this study suggest that the use of a simulation bite in maximal comfortable protrusion (MCP) of the mandible, as used during DISE in patients with OSA, tends to be effective in predicting treatment response of MAD treatment. © 2012 European Sleep Research Society.

Scissor bite in a young patient treated with an orthodontic-orthopedic device. A case report.

PubMed

Favero, V; Sbricoli, L; Favero, L

2013-06-01

Scissor bite is a rare malocclusion that often leads to minor facial asymmetry. An orthodontic and orthopaedic correction is advisable in young patients to prevent subsequent temporomandibular diseases requesting maxillofacial intervention. In this case report a 8-year-old girl in mixed dentition with unilateral left scissor bite was treated with a modified Rapid Palatal Expander. To modify an overexpanded maxilla (width 39 mm measured between both upper first molars) the device was used to close rather than to expand, without need of patient compliance. Orthodontic correction was then completed with traditional bracketing. Results were tangible (width 36 mm) and remained stable even for at least 2 years after retention. This original device has proved to be useful in this kind of situations and can be easily applied to young patient to correct such malocclusions.

Intramaxillary and intermaxillary absolute anchorage with an endosseous dental implant and rare-earth magnets.

PubMed

Uribe, Flavio; Nanda, Ravindra

2009-07-01

This case report describes the management of a partially edentulous adult with a severe deepbite malocclusion and a collapsed buccal segment because of supraeruption of the maxillary second and third molars. The treatment involved placement of an endosseous dental implant to achieve absolute intermaxillary and intramaxillary anchorage. Rare-earth magnets embedded in acrylic bite-blocks were used to intrude the supraerupted maxillary molars on the right side. After use as an anchorage device, the implant was restored and brought into occlusion. Good occlusal and esthetic results were achieved with this cost-effective treatment.

Chewing as a forming application: A viscoplastic damage law in modelling food oral breakdown

NASA Astrophysics Data System (ADS)

Skamniotis, C. G.; Charalambides, M. N.; Elliott, M.

2017-10-01

The first bite mechanical response of a food item resembles compressive forming processes, where a tool is pressed into a workpiece. The present study addresses ongoing interests in the deformations and damage of food products, particularly during the first bite, in relation to their mechanical properties. Uniaxial tension, compression and shear tests on a starch based food reveal stress-strain response and fracture strains strongly dependent on strain rate and stress triaxiality, while damage mechanisms are identified in the form of stress softening. A pressure dependent viscoplastic constitutive law reproduces the behavior with the aid of ABAQUS subroutines, while a ductile damage initiation and evolution framework based on fracture toughness data enables accurate predictions of the product breakdown. The material model is implemented in a Finite Element (FE) chewing model based on digital pet teeth geometry where the first bite of molar teeth against a food item is simulated. The FE force displacement results match the experimental data obtained by a physical replicate of the bite model, lending weight to the approach as a powerful tool in understanding of food breakdown and product development.

Contribution of jaw muscle size and craniofacial morphology to human bite force magnitude.

PubMed

Raadsheer, M C; van Eijden, T M; van Ginkel, F C; Prahl-Andersen, B

1999-01-01

The existence of an interaction among bite force magnitude, jaw muscle size (e.g., cross-sectional area, thickness), and craniofacial morphology is widely accepted. Bite force magnitude depends on the size of the jaw muscles and the lever arm lengths of bite force and muscle forces, which in turn are dictated by craniofacial morphology. In this study, the relative contributions of craniofacial morphology and jaw muscle thickness to the bite force magnitude were studied. In 121 adult individuals, both magnitude and direction of the maximal voluntary bite force were registered. Craniofacial dimensions were measured by anthropometrics and from lateral radiographs. The thicknesses of the masseter, temporal, and digastric muscles were registered by ultrasonography. After a factor analysis was applied to the anthropometric and cephalometric dimensions, the correlation between bite force magnitude, on the one hand, and the "craniofacial factors" and jaw muscle thicknesses, on the other, was assessed by stepwise multiple regression. Fifty-eight percent of the bite force variance could be explained. From the jaw muscles, only the thickness of the masseter muscle correlated significantly with bite force magnitude. Bite force magnitude also correlated significantly positively with vertical and transverse facial dimensions and the inclination of the midface, and significantly negatively with mandibular inclination and occlusal plane inclination. The contribution of the masseter muscle to the variation in bite force magnitude was higher than that of the craniofacial factors.

Expressly fabricated molar tube bases: enhanced adhesion.

PubMed

Sharma, Tarun; Phull, Tarun Singh; Rana, Tarun; Kumar, Varun

2014-06-01

Clinicians, Orthodontists and their patients' parents often expect the best results in the shortest time span possible. Orthodontic bonding of molar tubes has been an acceptable risk in a modern era of refined biomaterials and instrumentation. Although many orthodontists still prefer banding to bonding, it is the failure rate of the tubes on molars which accounts to an impedance in molar bonding. One of the reasons for molar attachment failures is attributed to improper adaptation of the buccal tube base with or without increased thickness of composite. Merits of banding the second molars especially when these are the terminal teeth for anchorage have been overemphasized in the literature. The present article presents a simple and relatively less time consuming technique of preparing molar tubes to be bonded on tooth surfaces which may be quite difficult to isolate especially for bonding, for example, mandibular second molars. The increased surface area of the composite scaffold helps not only in enhanced bond strength but also serves to reduce the incidence of plaque accumulation given the dexterity of invitro preparation. The removal of the occlusal part of the molar tube scaffold helps in prevention of open / raised bite tendencies. The present innovation, therefore, is not merely serendipity but a structured technique to overcome a common dilemma for the clinical orthodontist. The present dictum of banding being superior to molar tube bonding may prove to be futile with trendsetting molar attachments. It is also an established fact that bonding proves to be a lesser expensive modality when compared to banding procedures.

Craniomandibular System and Postural Balance after 3-Day Dry Immersion

PubMed Central

Treffel, Loïc; Dmitrieva, Liubov; Gauquelin-Koch, Guillemette; Custaud, Marc-Antoine; Blanc, Stéphane; Gharib, Claude; Millet, Catherine

2016-01-01

The objective of the study was to determine the influence of simulated microgravity by exposure to dry immersion on the craniomandibular system. Twelve healthy male volunteers participated in a 3-day dry immersion study. Before and immediately after exposure we measured maximal bite force using piezoresistive sensors. The mechanical properties of the jaw and cervical muscles were evaluated before, during, and after dry immersion using MyotonPRO. Because recent studies reported the effects of jaw motor activity on the postural stability of humans, stabilometric measurements of center of pressure were performed before and after dry immersion in two mandibular positions: rest position without jaw clenching, and intercuspidal position during voluntary teeth clenching. Results revealed no significant changes of maximal bite force after dry immersion. All postural parameters were significantly altered by dry immersion. There were however no significant differences in stabilometric data according to mandibular position. Moreover the masseter tonicity increased immediately after the end of dry immersion period. Dry immersion could be used as a valid model for studying the effects of microgravity on human subjects. However, 3 days appear insufficient in duration to evaluate the effects of weightlessness on maximal bite force. Our research suggests a link between postural disturbance after dry immersion and masseter tonicity. PMID:26913867

Feeding performance of king Mackerel, Scomberomorus cavalla.

PubMed

Ferguson, Amber R; Huber, Daniel R; Lajeunesse, Marc J; Motta, Philip J

2015-08-01

Feeding performance is an organism's ability to capture and handle prey. Although bite force is a commonly used metric of feeding performance, other factors such as bite pressure and strike speed are also likely to affect prey capture. Therefore, this study investigated static bite force, dynamic speeds, and predator and prey forces resulting from ram strikes, as well as bite pressure of the king mackerel, Scomberomorus cavalla, in order to examine their relative contributions to overall feeding performance. Theoretical posterior bite force ranged from 14.0-318.7 N. Ram speed, recorded with a rod and reel incorporated with a line counter and video camera, ranged from 3.3-15.8B L/s. Impact forces on the prey ranged from 0.1-1.9 N. Bite pressure, estimated using theoretical bite forces at three gape angles and tooth cross-sectional areas, ranged from 1.7-56.9 MPa. Mass-specific bite force for king mackerel is relatively low in comparison with other bony fishes and sharks, with relatively little impact force applied to the prey during the strike. This suggests that king mackerel rely on high velocity chases and high bite pressure generated via sharp, laterally compressed teeth to maximize feeding performance. © 2015 Wiley Periodicals, Inc.

Predicting bite force and cranial biomechanics in the largest fossil rodent using finite element analysis.

PubMed

Cox, Philip G; Rinderknecht, Andrés; Blanco, R Ernesto

2015-03-01

Josephoartigasia monesi, from the Pliocene of Uruguay, is the largest known fossil rodent, with an estimated body mass of 1000 kg. In this study, finite element analysis was used to estimate the maximum bite force that J. monesi could generate at the incisors and the cheek teeth. Owing to uncertainty in the model inputs, a sensitivity study was conducted in which the muscle forces and orientations were sequentially altered. This enabled conclusions to be drawn on the function of some of the masticatory muscles. It was found that J. monesi had a bite of 1389 N at the incisors, rising to 4165 N at the third molar. Varying muscle forces by 20% and orientations by 10° around the medio-lateral aspect led to an error in bite force of under 35% at each tooth. Predicted stresses across the skull were only minimally affected by changes to muscle forces and orientations, but revealed a reasonable safety factor in the strength of the skull. These results, combined with previous work, lead us to speculate that J. monesi was behaving in an elephant-like manner, using its incisors like tusks, and processing tough vegetation with large bite forces at the cheek teeth. © 2015 Anatomical Society.

Predicting bite force and cranial biomechanics in the largest fossil rodent using finite element analysis

PubMed Central

Cox, Philip G; Rinderknecht, Andrés; Blanco, R Ernesto

2015-01-01

Josephoartigasia monesi, from the Pliocene of Uruguay, is the largest known fossil rodent, with an estimated body mass of 1000 kg. In this study, finite element analysis was used to estimate the maximum bite force that J. monesi could generate at the incisors and the cheek teeth. Owing to uncertainty in the model inputs, a sensitivity study was conducted in which the muscle forces and orientations were sequentially altered. This enabled conclusions to be drawn on the function of some of the masticatory muscles. It was found that J. monesi had a bite of 1389 N at the incisors, rising to 4165 N at the third molar. Varying muscle forces by 20% and orientations by 10° around the medio-lateral aspect led to an error in bite force of under 35% at each tooth. Predicted stresses across the skull were only minimally affected by changes to muscle forces and orientations, but revealed a reasonable safety factor in the strength of the skull. These results, combined with previous work, lead us to speculate that J. monesi was behaving in an elephant-like manner, using its incisors like tusks, and processing tough vegetation with large bite forces at the cheek teeth. PMID:25652795

The relationship between facial skeleton morphology and bite force in people with a normal relation of the bases of jaws and skull.

PubMed

Sidorowicz, Ł; Szymańska, J

2015-01-01

Better knowledge on the relationship between craniofacial structure and bite force may serve as a reference point for prophylactic and therapeutic activities targeted at developmental age patients. The aim of the study was to assess the correlation between facial skeletal morphology and bite force. The study included 54 subjects aged 7-16 years with a normal relation of the bases of jaws and skull, according to Segner's and Hasund's analysis standards (ML-NL and ML-NSL angles values were 20.0 ± 7.0° and 28.0 ± 5.0°, respectively). The study group included patients who volunteered to diagnosis and possible orthodontic treatment. Bite force was tested with a digital dynamometer calibrated in Newtons. The measurement was performed at the level of the first permanent molars. Cephalometric analysis was based on lateral cephalometric radiographs. The vertical relations were assessed using the following measurements: ML-NSL, ML-NL, NL-NSL, N-Me, Sp-Me, SpMe:NMe, ms-NL, SGo:NMe. Bite force does not depend on the following factors: lower anterior face height (Sp-Me), lower anterior face height to total anterior face height ratio (SpMe:NMe), posterior to anterior face height ratio (SG0:NMe), and the value of ML-NL, ML-NSL and NL-NSL angles. The posterior height of the maxilla alveolar process (ms-NL) exerts the greatest influence on bite force in people with a normal relation of the bases of jaws and skull: with an increase in ms-NL value bite force is reduced.

Novel Low-Cost Sensor for Human Bite Force Measurement

PubMed Central

Fastier-Wooller, Jarred; Phan, Hoang-Phuong; Dinh, Toan; Nguyen, Tuan-Khoa; Cameron, Andrew; Öchsner, Andreas; Dao, Dzung Viet

2016-01-01

This paper presents the design and development of a low cost and reliable maximal voluntary bite force sensor which can be manufactured in-house by using an acrylic laser cutting machine. The sensor has been designed for ease of fabrication, assembly, calibration, and safe use. The sensor is capable of use within an hour of commencing production, allowing for rapid prototyping/modifications and practical implementation. The measured data shows a good linear relationship between the applied force and the electrical resistance of the sensor. The output signal has low drift, excellent repeatability, and a large measurable range of 0 to 700 N. A high signal-to-noise response to human bite forces was observed, indicating the high potential of the proposed sensor for human bite force measurement. PMID:27509496

Functional Evolution of the Feeding System in Rodents

PubMed Central

Cox, Philip G.; Rayfield, Emily J.; Fagan, Michael J.; Herrel, Anthony; Pataky, Todd C.; Jeffery, Nathan

2012-01-01

The masticatory musculature of rodents has evolved to enable both gnawing at the incisors and chewing at the molars. In particular, the masseter muscle is highly specialised, having extended anteriorly to originate from the rostrum. All living rodents have achieved this masseteric expansion in one of three ways, known as the sciuromorph, hystricomorph and myomorph conditions. Here, we used finite element analysis (FEA) to investigate the biomechanical implications of these three morphologies, in a squirrel, guinea pig and rat. In particular, we wished to determine whether each of the three morphologies is better adapted for either gnawing or chewing. Results show that squirrels are more efficient at muscle-bite force transmission during incisor gnawing than guinea pigs, and that guinea pigs are more efficient at molar chewing than squirrels. This matches the known diet of nuts and seeds that squirrels gnaw, and of grasses that guinea pigs grind down with their molars. Surprisingly, results also indicate that rats are more efficient as well as more versatile feeders than both the squirrel and guinea pig. There seems to be no compromise in biting efficiency to accommodate the wider range of foodstuffs and the more general feeding behaviour adopted by rats. Our results show that the morphology of the skull and masticatory muscles have allowed squirrels to specialise as gnawers and guinea pigs as chewers, but that rats are high-performance generalists, which helps explain their overwhelming success as a group. PMID:22558427

Occurrence of cervical invasive root resorption in first and second molar teeth of orthodontic patients eight years after bracket removal.

PubMed

Thönen, Andrea; Peltomäki, Timo; Patcas, Raphael; Zehnder, Matthias

2013-01-01

The occurrence and potential orthodontic causes of cervical invasive root resorption (CIRR) are unknown. We aimed to identify the occurrence of CIRR in molar teeth of orthodontic patients treated with fixed appliances. All patients invited for final orthodontic recall between November 2009 and March 2011 were included. From 175 patients, 108 (46 men/62 women; mean age, 25 ± 5 years; mean time after bracket removal, 8 ± 2 years) were available. The first and second molar teeth (N = 858) of these patients were investigated for clinical and radiographic signs of CIRR. Patients identified with such signs were asked to have limited-volume cone-beam computed tomography scans performed. No clinical signs of CIRR were detected. CIRR could not be ruled out on bite-wing radiographs in 18 patients. CIRR was thus identified in 1 patient in whom a second maxillary molar was affected. All first molars had been extracted in this patient, and the second molars had been moved mesially over a long distance. The 3 other second molars showed surface resorption. CIRR in molar teeth of orthodontic patients have a low mid-term occurrence (0.9%; 95% confidence interval, 0.2%-5.2%). Long movement distances and/or long treatment duration may be related to the development of these lesions. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Anchorage onto deciduous teeth: effectiveness of early rapid maxillary expansion in increasing dental arch dimension and improving anterior crowding.

PubMed

Mutinelli, Sabrina; Manfredi, Mario; Guiducci, Antonio; Denotti, Gloria; Cozzani, Mauro

2015-01-01

Anchorage onto permanent dentition is a common procedure in rapid maxillary expansion. However, replacing first permanent molars with the second deciduous molars seems to be an option to reduce some negative side effects during orthodontic treatment. The purpose of this study was to evaluate the dental effect of rapid maxillary expansion with anchorage exclusively onto deciduous teeth performed in the first period of transition. Twenty patients with a lateral cross-bite treated exclusively by a Haas expander in early mixed dentition were retrospectively analyzed before treatment, at appliance removal, and at 21 months out of retention. The sagittal and transverse dimensions, together with the inter-canine arch and irregularity index, were digitally measured on scanned images of dental casts. The patients were compared with three balanced control groups (in total, 60 individuals) matched for gender. Two control groups had the same canine dental class as the treated group at T1, were in the inter-transitional period, and either had or lacked a lateral cross-bite. The last control group was comprised of adolescents in permanent dentition with a dental class I. The statistical analysis was performed by means of repeated-measures ANOVA for paired data and one-way ANOVA, the Kruskal-Wallis test, and the Mann-Whitney test for independent measures (α-level p < 0.05). At the end of follow-up (inter-transitional period of dentition), the dental arch dimensions of treated patients were similar to those of adolescents with a dental class I and significantly wider than those of patients with a lateral cross-bite. Also, the anterior irregularity index was lower among patients who had undergone expansion treatments than in all untreated study participants. The Haas expander anchored to the deciduous teeth is effective in increasing the dental arch width in patients with a lateral cross-bite. The dimensions of the dental arch were modified earlier toward the values of the permanent dentition.

Role of multiple cusps in tooth fracture.

PubMed

Barani, Amir; Bush, Mark B; Lawn, Brian R

2014-07-01

The role of multiple cusps in the biomechanics of human molar tooth fracture is analysed. A model with four cusps at the bite surface replaces the single dome structure used in previous simulations. Extended finite element modelling, with provision to embed longitudinal cracks into the enamel walls, enables full analysis of crack propagation from initial extension to final failure. The cracks propagate longitudinally around the enamel side walls from starter cracks placed either at the top surface (radial cracks) or from the tooth base (margin cracks). A feature of the crack evolution is its stability, meaning that extension occurs steadily with increasing applied force. Predictions from the model are validated by comparison with experimental data from earlier publications, in which crack development was followed in situ during occlusal loading of extracted human molars. The results show substantial increase in critical forces to produce longitudinal fractures with number of cuspal contacts, indicating a capacity for an individual tooth to spread the load during mastication. It is argued that explicit critical force equations derived in previous studies remain valid, at the least as a means for comparing the capacity for teeth of different dimensions to sustain high bite forces. Copyright © 2014 Elsevier Ltd. All rights reserved.

Treatment and retention of relapsed anterior open-bite with low tongue posture and tongue-tie: A 10-year follow-up

PubMed Central

Seo, Yu-Jin; Kim, Su-Jung; Munkhshur, Janchivdorj; Chung, Kyu-Rhim; Ngan, Peter

2014-01-01

The purpose of the current report is to present 6-year long-term stability and 10-year follow-up data for an adult patient who was treated with a tongue elevator for relapsed anterior open-bite. The 19-year-old male patient presented with the chief complaint of difficulty in chewing his food. Collectively, clinical and radiographic examinations revealed an anterior open-bite, low tongue posture, and tongue-tie. The patient opted for orthodontic treatment alone, without any surgical procedure. A lingual frenectomy was recommended to avoid the risk of relapse, but the patient declined because he was not experiencing tongue discomfort. Initial treatment of the anterior open-bite with molar intrusion and tongue exercises was successful, but relapse occurred during the retention period. A tongue elevator was used for retreatment, because the approach was minimally invasive and suited the patient's requirements regarding discomfort, cost, and time. The appliance changed the tongue posture and generated an altered tongue force, which ultimately resulted in intrusive dentoalveolar effects, and a subsequent counterclockwise rotation of the mandible. The results showed long-term stability and were maintained for six years through continual use of the tongue elevator. The results of this case indicated that a tongue elevator could be used not only as an alternative treatment for open-bite, but also as an active retainer. PMID:25133135

Precision of a CAD/CAM-engineered surgical template based on a facebow for orthognathic surgery: an experiment with a rapid prototyping maxillary model.

PubMed

Lee, Jae-Won; Lim, Se-Ho; Kim, Moon-Key; Kang, Sang-Hoon

2015-12-01

We examined the precision of a computer-aided design/computer-aided manufacturing-engineered, manufactured, facebow-based surgical guide template (facebow wafer) by comparing it with a bite splint-type orthognathic computer-aided design/computer-aided manufacturing-engineered surgical guide template (bite wafer). We used 24 rapid prototyping (RP) models of the craniofacial skeleton with maxillary deformities. Twelve RP models each were used for the facebow wafer group and the bite wafer group (experimental group). Experimental maxillary orthognathic surgery was performed on the RP models of both groups. Errors were evaluated through comparisons with surgical simulations. We measured the minimum distances from 3 planes of reference to determine the vertical, lateral, and anteroposterior errors at specific measurement points. The measured errors were compared between experimental groups using a t test. There were significant intergroup differences in the lateral error when we compared the absolute values of the 3-D linear distance, as well as vertical, lateral, and anteroposterior errors between experimental groups. The bite wafer method exhibited little lateral error overall and little error in the anterior tooth region. The facebow wafer method exhibited very little vertical error in the posterior molar region. The clinical precision of the facebow wafer method did not significantly exceed that of the bite wafer method. Copyright © 2015 Elsevier Inc. All rights reserved.

Development of caries in permanent first molars adjacent to primary second molars with interproximal caries: four-year prospective radiographic study.

PubMed

Vanderas, Apostole P; Kavvadia, Katerina; Papagiannoulis, Lisa

2004-01-01

This study investigated the effect of the primary second molars' distal surface caries on the incidence of the permanent first molars' mesial surface caries in 613 paired tooth surfaces of children ages 6 to 8 years at baseline examination. Proximal caries and its progression were diagnosed by bite-wing radiographs taken at a 1-year interval over a period of 4 years. The permanent first molars' mesial surfaces and primary second molars' distal surfaces were examined. Recorded were: (1) sound surfaces; (2) carious lesions on the enamel's external and internal half and on the dentin's external, middle, and internal third; (3) filled, extracted, and exfoliated teeth. The logistic model for panel data was employed to estimate the effect of proximal caries of the primary second molars' distal surfaces on the incidence of the permanent first molars' mesial surface caries. The 95% confidence interval probability was used. Sensitivity and specificity as well as the positive and negative predictive rates were computed. The results showed that the presence of proximal caries on each primary second molars' distal surfaces significantly affected the development of proximal caries on the corresponding permanent first molar's mesial surfaces. Age was estimated to exert a positive and highly significant impact, while gender had no effect. The odds ratio values ranged from 4.86 to 63.43. The values of sensitivity and specificity ranged from 45% to 97% and 80% to 89%, respectively, while the positive and negative rates ranged from 40% to 56% and 90% to 99%, respectively. Proximal caries present on the primary second molars' distal surfaces increases the risk of developing caries on the permanent first molars' mesial surfaces. This risk, however, is different among the paired surfaces studied.

Realistic kinetic loading of the jaw system during single chewing cycles: a finite element study.

PubMed

Martinez Choy, S E; Lenz, J; Schweizerhof, K; Schmitter, M; Schindler, H J

2017-05-01

Although knowledge of short-range kinetic interactions between antagonistic teeth during mastication is of essential importance for ensuring interference-free fixed dental reconstructions, little information is available. In this study, the forces on and displacements of the teeth during kinetic molar biting simulating the power stroke of a chewing cycle were investigated by use of a finite-element model that included all the essential components of the human masticatory system, including an elastic food bolus. We hypothesised that the model can approximate the loading characteristics of the dentition found in previous experimental studies. The simulation was a transient analysis, that is, it considered the dynamic behaviour of the jaw. In particular, the reaction forces on the teeth and joints arose from contact, rather than nodal forces or constraints. To compute displacements of the teeth, the periodontal ligament (PDL) was modelled by use of an Ogden material model calibrated on the basis of results obtained in previous experiments. During the initial holding phase of the power stroke, bite forces were aligned with the roots of the molars until substantial deformation of the bolus occurred. The forces tilted the molars in the bucco-lingual and mesio-distal directions, but as the intrusive force increased the teeth returned to their initial configuration. The Ogden material model used for the PDL enabled accurate prediction of the displacements observed in experimental tests. In conclusion, the comprehensive kinetic finite element model reproduced the kinematic and loading characteristics of previous experimental investigations. © 2017 John Wiley & Sons Ltd.

Comparative gene expression supports the origin of the incisor and molar process from a single endite in the mandible of the red flour beetle Tribolium castaneum

PubMed Central

2013-01-01

Background The biting edge of the primitive arthropod mandible consists of a biting incisor process and a crushing molar process. These structures are thought to be derived from a structure known as an endite but the precise details of this are not understood. Various hypotheses concerning the number of endites present in the arthropod mandible have been proposed. In the developing embryo, the mandible has an inner and outer lobe that are likely to develop into the incisor and molar processes of the larval mandible; these two lobes are commonly held to be derived from separate endites and to be serially homologous to the galea and lacinia endites of the maxillary appendage respectively (Machida). Results We undertook a study of the development of the embryonic mandible of the beetle Tribolium castaneum using the expression of developmental genes as markers of the developing endites in the mandible and maxilla. The Tribolium ortholog of paired (Tc-prd) has expression domains in the developing maxillary and labial endites as well as the inner and outer lobes of the mandible. Following the expression of Tc-prd in the developing mandible through to late stage embryos shows that the molar and incisor process develop from the inner and outer lobes respectively. In addition to Tc-prd, we compared the expression of genes in the endites of the maxilla to the mandible to draw conclusions about the number of endites in the mandible. Homologs of dachshund are typically expressed in the endites of mandibulate gnathal appendages. Comparison of the expression of Tc-prd, Tribolium dachshund (Tc-dac) and Tribolium wingless (Tc-wg) between the endites of the maxilla and the mandible suggest that, while there are two endites in the maxilla only a single endite is present in the mandible. Conclusions Comparative gene expression suggests that the Tribolium mandible has a single endite from which both mandible lobes are derived. Our results do not support Machida’s hypothesis homologising the incisor and molar processes of the mandible to the galea and lacinia endites of the maxilla. We propose, instead, that both incisor and molar processes are derived from a single endite serially homologous to the lacinia of the maxilla. PMID:23280103

Finite element modelling of squirrel, guinea pig and rat skulls: using geometric morphometrics to assess sensitivity.

PubMed

Cox, P G; Fagan, M J; Rayfield, E J; Jeffery, N

2011-12-01

Rodents are defined by a uniquely specialized dentition and a highly complex arrangement of jaw-closing muscles. Finite element analysis (FEA) is an ideal technique to investigate the biomechanical implications of these specializations, but it is essential to understand fully the degree of influence of the different input parameters of the FE model to have confidence in the model's predictions. This study evaluates the sensitivity of FE models of rodent crania to elastic properties of the materials, loading direction, and the location and orientation of the models' constraints. Three FE models were constructed of squirrel, guinea pig and rat skulls. Each was loaded to simulate biting on the incisors, and the first and the third molars, with the angle of the incisal bite varied over a range of 45°. The Young's moduli of the bone and teeth components were varied between limits defined by findings from our own and previously published tests of material properties. Geometric morphometrics (GMM) was used to analyse the resulting skull deformations. Bone stiffness was found to have the strongest influence on the results in all three rodents, followed by bite position, and then bite angle and muscle orientation. Tooth material properties were shown to have little effect on the deformation of the skull. The effect of bite position varied between species, with the mesiodistal position of the biting tooth being most important in squirrels and guinea pigs, whereas bilateral vs. unilateral biting had the greatest influence in rats. A GMM analysis of isolated incisor deformations showed that, for all rodents, bite angle is the most important parameter, followed by elastic properties of the tooth. The results here elucidate which input parameters are most important when defining the FE models, but also provide interesting glimpses of the biomechanical differences between the three skulls, which will be fully explored in future publications. © 2011 The Authors. Journal of Anatomy © 2011 Anatomical Society of Great Britain and Ireland.

Skeletal class III malocclusion treated using a non-surgical approach supplemented with mini-implants: a case report.

PubMed

Farret, Marcel Marchiori; Benitez Farret, Milton M

2013-09-01

We describe a 28-year-old man who sought orthodontic treatment complaining about the esthetics of his smile and difficulties associated with masticatory function. The patient had a straight facial profile, skeletal and dental class III relationship, anterior open bite and posterior crossbite. He refused orthognathic surgery and was therefore treated with camouflage orthodontics supplemented with the placement of one mini-implant in each side of the mandible to facilitate movement of the lower dentition distally, tooth-by-tooth. At the end of treatment, a class I molar relationship was obtained, with an ideal overjet and overbite and excellent intercuspation. Furthermore, the open bite and crossbite were corrected. Analysis 2 years after treatment revealed good stability of treatment outcome.

Biology of biomechanics: Finite element analysis of a statically determinate system to rotate the occlusal plane for correction of a skeletal Class III open-bite malocclusion.

PubMed

Roberts, W Eugene; Viecilli, Rodrigo F; Chang, Chris; Katona, Thomas R; Paydar, Nasser H

2015-12-01

In the absence of adequate animal or in-vitro models, the biomechanics of human malocclusion must be studied indirectly. Finite element analysis (FEA) is emerging as a clinical technology to assist in diagnosis, treatment planning, and retrospective analysis. The hypothesis tested is that instantaneous FEA can retrospectively simulate long-term mandibular arch retraction and occlusal plane rotation for the correction of a skeletal Class III malocclusion. Seventeen published case reports were selected of patients treated with statically determinate mechanics using posterior mandible or infrazygomatic crest bone screw anchorage to retract the mandibular arch. Two-dimensional measurements were made for incisor and molar movements, mandibular arch rotation, and retraction relative to the maxillary arch. A patient with cone-beam computed tomography imaging was selected for a retrospective FEA. The mean age for the sample was 23.3 ± 3.3 years; there were 7 men and 10 women. Mean incisor movements were 3.35 ± 1.55 mm of retraction and 2.18 ± 2.51 mm of extrusion. Corresponding molar movements were retractions of 4.85 ± 1.78 mm and intrusions of 0.85 ± 2.22 mm. Retraction of the mandibular arch relative to the maxillary arch was 4.88 ± 1.41 mm. Mean posterior rotation of the mandibular arch was -5.76° ± 4.77° (counterclockwise). The mean treatment time (n = 16) was 36.2 ± 15.3 months. Bone screws in the posterior mandibular region were more efficient for intruding molars and decreasing the vertical dimension of the occlusion to close an open bite. The full-cusp, skeletal Class III patient selected for FEA was treated to an American Board of Orthodontics Cast-Radiograph Evaluation score of 24 points in about 36 months by en-masse retraction and posterior rotation of the mandibular arch: the bilateral load on the mandibular segment was about 200 cN. The mandibular arch was retracted by about 5 mm, posterior rotation was about 16.5°, and molar intrusion was about 3 mm. There was a 4° decrease in the mandibular plane angle to close the skeletal open bite. Retrospective sequential iterations (FEA animation) simulated the clinical response, as documented with longitudinal cephalometrics. The level of periodontal ligament stress was relatively uniform (<5 kPa) for all teeth in the mandibular arch segment. En-masse retraction of the mandibular arch is efficient for conservatively treating a skeletal Class III malocclusion. Posterior mandibular anchorage causes intrusion of the molars to close the vertical dimension of the occlusion and the mandibular plane angle. Instantaneous FEA as modeled here could be used to reasonably predict the clinical results of an applied load. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Electromyographic and cephalometric correlation with the predominant masticatory movement.

PubMed

Coelho-Ferraz, Maria Julia P; Berzin, Fausto; Amorim, Cesar Ferreira; Romano, Fabio Lourenco; de Paula Queluz, Dagmar

2010-01-01

This study aimed to evaluate the chewing muscular dynamics and correlate the side of the masticatory movement that is more vertical and/or more horizontal established by the photomeasurement Masticatory Functional Angle (MFA) to the muscular activity behavior, showed in the surface electromyography and in the radiographic images. Seventeen people were selected of both genders, with the average age of 25 years, without signs or apparent symptoms of masticatory muscular disorders. The teleradiographies were done in lateral norm and surface electromyography of the masseter muscles, anterior portion of temporal and supra-hyoids in rest position and maximal bite. The bite force measured with a metallic transducer that was connected to a force sensor (Strain Gauge) to measure the deformation of the material model SF4 (EMG SYSTEM DO BRASIL). A mandibular goniometer of the EMG System of Brazil was used to measure the opening size. The comparison and correlation were established between the groups with MFA>5 degrees and MFA<5 degrees by the test "t" of Student or test of Mann-Whitney conform the distribution was normal or not, respectively. The results showed significant differences between groups, although without sexual dimorphism, to masseter muscle in maximal bite. In conclusion, the anatomic-physiological aspects of temporomandibular disorders are related to the asymmetrical mandible function.

Human feeding biomechanics: performance, variation, and functional constraints

PubMed Central

Dechow, Paul C.; Wang, Qian; Gharpure, Poorva H.; Baab, Karen L.; Smith, Amanda L.; Weber, Gerhard W.; Grosse, Ian R.; Ross, Callum F.; Richmond, Brian G.; Wright, Barth W.; Byron, Craig; Wroe, Stephen; Strait, David S.

2016-01-01

The evolution of the modern human (Homo sapiens) cranium is characterized by a reduction in the size of the feeding system, including reductions in the size of the facial skeleton, postcanine teeth, and the muscles involved in biting and chewing. The conventional view hypothesizes that gracilization of the human feeding system is related to a shift toward eating foods that were less mechanically challenging to consume and/or foods that were processed using tools before being ingested. This hypothesis predicts that human feeding systems should not be well-configured to produce forceful bites and that the cranium should be structurally weak. An alternate hypothesis, based on the observation that humans have mechanically efficient jaw adductors, states that the modern human face is adapted to generate and withstand high biting forces. We used finite element analysis (FEA) to test two opposing mechanical hypotheses: that compared to our closest living relative, chimpanzees (Pan troglodytes), the modern human craniofacial skeleton is (1) less well configured, or (2) better configured to generate and withstand high magnitude bite forces. We considered intraspecific variation in our examination of human feeding biomechanics by examining a sample of geographically diverse crania that differed notably in shape. We found that our biomechanical models of human crania had broadly similar mechanical behavior despite their shape variation and were, on average, less structurally stiff than the crania of chimpanzees during unilateral biting when loaded with physiologically-scaled muscle loads. Our results also show that modern humans are efficient producers of bite force, consistent with previous analyses. However, highly tensile reaction forces were generated at the working (biting) side jaw joint during unilateral molar bites in which the chewing muscles were recruited with bilateral symmetry. In life, such a configuration would have increased the risk of joint dislocation and constrained the maximum recruitment levels of the masticatory muscles on the balancing (non-biting) side of the head. Our results do not necessarily conflict with the hypothesis that anterior tooth (incisors, canines, premolars) biting could have been selectively important in humans, although the reduced size of the premolars in humans has been shown to increase the risk of tooth crown fracture. We interpret our results to suggest that human craniofacial evolution was probably not driven by selection for high magnitude unilateral biting, and that increased masticatory muscle efficiency in humans is likely to be a secondary byproduct of selection for some function unrelated to forceful biting behaviors. These results are consistent with the hypothesis that a shift to softer foods and/or the innovation of pre-oral food processing techniques relaxed selective pressures maintaining craniofacial features that favor forceful biting and chewing behaviors, leading to the characteristically small and gracile faces of modern humans. PMID:27547550

Six-year follow-up in skeletal Class III patient aged over 40 receiving orthognathic surgery and autotransplantation: a case report.

PubMed

Motegi, Etsuko; Takane, Yumi; Tokunaga, Eri; Sueishi, Kenji; Takano, Nobuo; Shibahara, Takahiko; Saito, Chikara

2009-08-01

This paper describes the post-operative course of care in a patient requiring orthognathic surgery for skeletal mandibular protrusion in whom autotransplantation of a third molar was performed. A lower third molar that had to be removed for sagittal split ramus osteotomy (SSRO) was transplanted to replace the missing right second molar during pre-surgical orthodontic treatment, contributing to post-treatment occlusal stability. A 44-year-old woman presented with mandibular protrusion. The upper left second molar was congenitally missing and the lower right second molar had been extracted. She was diagnosed as having skeletal mandibular protrusion with excess vertical growth of the mandible and anterior open bite. Correction of the skeletal problem required orthognathic surgery by SSRO and Le Fort I osteotomy without orthodontic tooth extraction. At month 5 during 18 months of pre-surgical orthodontic treatment, the lower left third molar was transplanted to the lower right second molar site. Active treatment was completed after 7 months of post-surgical orthodontic treatment. The patient wore upper and lower Begg-type removable retainers for approximately 2 years. She returned for a recall checkup at 6 years post-treatment. Although radiographic examination revealed root resorption and ankylosis of the autotransplanted tooth at 8 years after transplantation, occlusion has remained stable with no clinically significant complications. The autotransplanted tooth helped stabilize her occlusion and acted as a kind of temporary tooth prior to the final decision on treatment to be given such a dental implant.

Spontaneous correction of anterior crossbite by RPE anchored on deciduous teeth in the early mixed dentition.

PubMed

Rosa, M; Lucchi, P; Mariani, L; Caprioglio, A

2012-09-01

The purpose of this study was to evaluate the effectiveness of Haas RPE anchored on deciduous teeth in the early mixed dentition, for inducing the spontaneous correction of permanent incisor's crossbite, without compliance, without post bite-plane and no involvement of the permanent teeth. The sample group comprised 50 consecutive patients (mean age 8y 5m, SD 2y 1m), 31 males, 19 females. They showed a cross-bite affecting one or more permanent incisors, for a total of 70 teeth. The patients were treated with Haas RPE appliance anchored on second deciduous molars and bonded on deciduous canines. No direct forces were applied on the permanent teeth. Anterior crossbite self-corrected 'spontaneously' in 84% of the cases. Lateral incisors had a higher rate of self-correction than central incisors. All hyper-divergent subjects showed a spontaneous crossbite self-correction. The early maxillary expansion by Haas RPE anchored on deciduous teeth is an efficient and effective procedure to induce the anterior crossbite self-correction in the early mixed dentition without the need of a bite-plane, no involvement of the permanent teeth and without compliance.

The anterior component of occlusal force revisited: direct measurement and theoretical considerations.

PubMed

Al Qassar, Sarmad S Salih; Mavragani, Maria; Psarras, Vasilis; Halazonetis, Demetrios J

2016-04-01

The anterior component of occlusal force (ACF), considered to result from the mesial inclination of teeth relative to the occlusal plane, has been estimated by indirectly measuring contact point tightness (CPT) through interproximal insertion of metal strips. ACF has been observed concurrently with a posterior component, whose theoretical origin is difficult to explain. Evaluate ACF by measuring CPT directly, and integrate current data to propose a theoretical basis for ACF. The sample comprised 14 females (age: 22.3±2.8) and 16 males (age: 20.8±2.5). Our device consisted of two force sensors: one for measuring maximum bite force (MBF) (overall thickness: 4mm), and one for measuring CPT directly (0.2mm thick), inserted between the lower first molar and second premolar. ACF was computed as the difference in CPT between the biting (at 75 per cent of MBF) and non-biting conditions. Averages of MBF, CPT, and ACF were 666.67 [standard deviation (SD): 36.06], 6.74 (SD: 1.17), and 20.59 (SD: 4.60) N, respectively. ACF, CPT, and MBF were higher in males by approximately 28, 18 and 7 per cent, respectively. A positive correlation was observed between ACF and MBF (R (2): 0.64). CPT was also significantly correlated to MBF (R (2): 0.40). Biomechanical analysis indicates that previously offered explanations do not unriddle the concurrent increase of CPT at anterior and posterior contact points. ACF was related to bite force by a logarithmic model. We speculate that CPT increases during biting through a combination of mesial tipping of teeth and mandibular bending. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Maxillary tridimensional changes after slow expansion with leaf expander in a sample of growing patients: a pilot study.

PubMed

Lanteri, V; Gianolio, A; Gualandi, G; Beretta, M

2018-03-01

The aim of this study is to evaluate the dento-alveolar effects of slow maxillary expansion using the Leaf Expander in a sample of growing patients with maxillary transverse deficiency, unilateral cross bite and mandibular shift. The study included 10 patients, 3 male and 7 female (mean age 7.5 + 7 months), treated with Leaf Expander anchored on the upper deciduous teeth. Digital models were obtained by a lab scan of the pvs impressions at the beginning of the therapy (T1) and at the removal of the palatal expander (T2). Five parameters were measured: 1) the distance between the first upper permanent molars; 2) the distance between the upper second deciduous molars; 3) the distance between the upper canine cusps 4) the distance between the first lower permanent molars; 5) the distance of the lower canine cusps. In all patients complete correction of posterior crossbite was achieved on average in 4 months, with a spontaneous expansion of the upper first permanent molars. Significant increases in the dento-alveolar transversal diameters were obtained. Increases were also observed in the anterior mandibular arch diameter (+ 1 mm). These findings suggest that slow maxillary expansion using Leaf Expander appliance could be a reasonable alternative to conventional maxillary expansion therapy in the early mixed dentition.

Resting position of the head and malocclusion in a group of patients with cerebral palsy

PubMed Central

Martinez-Mihi, Victoria; Orellana, Lorena M.; Silvestre-Rangil, Javier

2014-01-01

Cerebral palsy are found as a result of these disorders, along with associated neuromuscular functional alterations that affect the resting position of the head. In this context, the resting position of the head could be responsible for several skeletal and dental occlusal disorders among patients with cerebral palsy. Objective: To assess the presence of malocclusions in patients with cerebral palsy, define the most frequent types of malocclusions, and evaluate how the resting position of the head may be implicated in the development of such malocclusions. Study design: Forty-four patients aged between 12-55 years (18 males and 26 females) were studied. Occlusal conditions, the Dental Aesthetic Index (DAI), changes in the resting position of the head, and breathing and swallowing functions were assessed. Results: Orthodontic treatment was required by 70.8% of the patients, the most frequent malocclusions being molar class II, open bite and high overjet. These individuals showed altered breathing and swallowing functions, as well as habit and postural disorders. The resting position of the head, especially the hyperextended presentation, was significantly correlated to high DAI scores. Conclusions: The results obtained suggest that patients with cerebral palsy are more susceptible to present malocclusions, particularly molar class II malocclusion, increased open bite, and high overjet. Such alterations in turn are more common in patients with a hyperextended position of the head. Key words:Cerebral palsy, malocclusion, head position, disabled patients. PMID:24596627

Structural biomechanics of the craniomaxillofacial skeleton under maximal masticatory loading: Inferences and critical analysis based on a validated computational model.

PubMed

Pakdel, Amir R; Whyne, Cari M; Fialkov, Jeffrey A

2017-06-01

The trend towards optimizing stabilization of the craniomaxillofacial skeleton (CMFS) with the minimum amount of fixation required to achieve union, and away from maximizing rigidity, requires a quantitative understanding of craniomaxillofacial biomechanics. This study uses computational modeling to quantify the structural biomechanics of the CMFS under maximal physiologic masticatory loading. Using an experimentally validated subject-specific finite element (FE) model of the CMFS, the patterns of stress and strain distribution as a result of physiological masticatory loading were calculated. The trajectories of the stresses were plotted to delineate compressive and tensile regimes over the entire CMFS volume. The lateral maxilla was found to be the primary vertical buttress under maximal bite force loading, with much smaller involvement of the naso-maxillary buttress. There was no evidence that the pterygo-maxillary region is a buttressing structure, counter to classical buttress theory. The stresses at the zygomatic sutures suggest that two-point fixation of zygomatic complex fractures may be sufficient for fixation under bite force loading. The current experimentally validated biomechanical FE model of the CMFS is a practical tool for in silico optimization of current practice techniques and may be used as a foundation for the development of design criteria for future technologies for the treatment of CMFS injury and disease. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

An Approach with Hybrid Segmental Mechanics.

PubMed

Mishra, Harsh Ashok; Maurya, Raj Kumar

2016-06-01

Present case report provides an insight into the hybrid segmental mechanics with treatment of 13-year-old male, considering the side effects of sole continuous arch wire sliding mechanics. Patient was diagnosed as a case of skeletal class I jaw relationship, low mandibular plane angle, class II molar relation on right and class I molar relation on left side, anterior cross bite, crowding of 12mm in upper, 5mm in lower arch. He also had proclined upper and lower anteriors by 2mm, convex profile and incompetent lips. Total treatment duration was 20 months, during which segmental canine retraction was performed with TMA (Titanium, Molybdenum, Aluminum) 'T' loop retraction spring followed by consolidation of spaces with continuous arch mechanics. Most of the treatment objectives were met with good intraoral and facial results within reasonable framework of time. This approach used traditional twin brackets, which offered the versatility to use continuous arch-wire mechanics, segmental mechanics and hybrid sectional mechanics.

Influence of sustained submaximal clenching fatigue test on electromyographic activity and maximum voluntary bite forces in healthy subjects and patients with temporomandibular disorders.

PubMed

Xu, L; Fan, S; Cai, B; Fang, Z; Jiang, X

2017-05-01

This study aimed to investigate whether the fatigue induced by sustained motor task in the jaw elevator muscles differed between healthy subjects and patients with temporomandibular disorder (TMD). Fifteen patients with TMD and thirteen age- and sex-matched healthy controls performed a fatigue test consisting of sustained clenching contractions at 30% maximal voluntary clenching intensity until test failure (the criterion for terminating the fatigue test was when the biting force decreased by 10% or more from the target force consecutively for >3 s). The pre- and post-maximal bite forces (MBFs) were measured. Surface electromyographic signals were recorded from the superficial masseter muscles and anterior temporal muscles bilaterally, and the median frequency at the beginning, middle and end of the fatigue test was calculated. The duration of the fatigue test was also quantified. Both pre- and post-MBFs were lower in patients with TMD than in controls (P < 0·01). No significant difference was found in the percentage change in MBF between groups. The duration of the fatigue test in TMD patients was significantly shorter than that of the controls (P < 0·05). Our results suggest that, compared to healthy subjects, patients with TMD become more easily fatigued, but the electromyographic activation process during the fatigue test is similar between healthy subjects and patients with TMD. However, the mechanisms involved in this process remain unclear, and further research is warranted. © 2017 John Wiley & Sons Ltd.

Occlusal contact of fixed implant prostheses using functional bite impression technique.

PubMed

Suzuki, Yasunori; Shimpo, Hidemasa; Ohkubo, Chikahiro

2015-02-01

Functional bite impression (FBI) has been described as a definitive impression made under occlusal force after functional generated path (FGP) recording. This study compared the accuracy of occlusal contact of implant-fixed prostheses using the FBI technique and the conventional impression technique. Twelve subjects, each missing a single premolar or molar, were selected for this study. The conditions of the occlusal contacts were identified by the modified transillumination method. The occlusal contact condition was determined by comparing the rate of change in the occlusal contact area of the implant-fixed prostheses and both adjacent teeth before and after occlusal adjustment. The rate of change in the occlusal contact area using the FBI technique was 96%, and the rate using the conventional technique was 54%. The occlusal contact of implant prostheses using the FBI technique revealed better accuracy than that of the conventional technique. Regarding the FBI technique, a precise and functional prosthesis could be produced by completing the maxillomandibular registration, impression, and FGP at the same time.

CBVT analysis of canal configuration of the mesio-buccal root of maxillary first permanent molar teeth: An in vitro study.

PubMed

Shenoi, R Pratima; Ghule, Hrishikesh M

2012-07-01

For successful endodontic treatment, it's imperative to locate and obturate all root canals. As concluded by Ingle, the major cause for failure of root canal therapy is in ability to recognize all theexisting canals and subsequent failure in their obturation. To analyze the canal configuration of the mesio-buccal root of maxillary first permanent molar teeth. A total of 30 recently extracted human permanent maxillary first molars were collected and stored in a container with 5% Sodium Chloride solution for four days. Teeth with open apices, external resorption, improperly formed roots and teeth with previous restorations were excluded. Using the dental modeling wax, teeth were arranged in a 'U' shaped arch with roots embedded inside the wax and occlusal surface remaining free. 10 teeth were arranged in each arch and three such sample plates were prepared. Flat surface of the base encasing enabled the plate to be mounted on flat plastic bite plate. With bite plate roughly centered in the focal trough area Axial, Coronal and Sagittal section Cone-Beam Computed Tomography (CBCT) images were taken with Kodak 9000 Extra-oral Imaging System. Images displayed on a monitor were inspected by two endodontists using Kodak Dental Imaging Software 3D Module V2.2. When the data was observed, it was found that 24 teeth out of total 30 teeth examined showed some variation (i.e. possible additional canal) along the length of the mesio-buccal root canal. Out of these 24 teeth, 13 showed presence of additional canal at coronal third, 7 showed presence of additional canal at middle third and four showed presence of additional canal in apical third level. Percentage analysis was done as there was no group comparison to be done. Cone-Beam Volumetric Tomography (CBVT) evaluation positively identified the variations in mesio-buccal canal in 80% of samples. Out of these, 54.16% were in coronal 3(rd), 29.16% in middle 3(rd) and 16.66% were in apical 3(rd). Within the limitations of this study, it can be concluded that- (1) more than half of maxillary first molars have four canals and (2) most of the additional canals were located in the MBR and CBVT is a good diagnostic tool to help diagnose these additional canals. Further investigations using larger sample sizes would be helpful.

Masticatory muscle architecture in a water-rat from Australasia (Murinae, Hydromys) and its implication for the evolution of carnivory in rodents.

PubMed

Fabre, P-H; Herrel, A; Fitriana, Y; Meslin, L; Hautier, L

2017-09-01

Murines are well known for their generalist diet, but several of them display specializations towards a carnivorous diet such as the amphibious Indo-Pacific water-rats. Despite the fact that carnivory evolved repeatedly in this group, few studies have investigated associated changes in jaw muscle anatomy and biomechanics. Here, we describe the jaw muscles and cranial anatomy of a carnivorous water-rat, Hydromys chrysogaster. The architecture of the jaw musculature of six specimens captured both on Obi and Papua were studied and described using dissections. We identified the origin and insertions of the jaw muscles, and quantified muscle mass, fiber length, physiological cross-sectional area, and muscle vectors for each muscle. Using a biomechanical model, we estimated maximum incisor and molar bite force at different gape angles. Finally, we conducted a 2D geometric morphometric analyses to compare jaw shape, mechanical potential, and diversity in lever-arm ratios for a set of 238 specimens, representative of Australo-Papuan carnivorous and omnivorous murids. Our study reveals major changes in the muscle proportions among Hydromys and its omnivorous close relative, Melomys. Hydromys was found to have large superficial masseter and temporalis muscles as well as a reduced deep masseter and zygomatico-mandibularis, highlighting major functional divergence among omnivorous and carnivorous murines. Changes in these muscles are also accompanied by changes in jaw shape and the lines of action of the muscles. A more vertically oriented masseter, reduced masseteric muscles, as well as an elongated jaw with proodont lower incisors are key features indicative of a reduced propalinality in carnivorous Hydromys. Differences in the fiber length of the masseteric muscles were also detected between Hydromys and Melomys, which highlight potential adaptations to a wide gape in Hydromys, allowing it to prey on larger animals. Using a biomechanical model, we inferred a greater bite force in Hydromys than in Melomys, implying a functional shift between omnivory and carnivory. However, Melomys has an unexpected greater bite force at large gape compared with Hydromys. Compared with omnivorous Melomys, Hydromys have a very distinctive low mandible with a well-developed coronoid process, and a reduced angular process that projects posteriorly to the ascending rami. This jaw shape, along with our mechanical potential and jaw lever ratio estimates, suggests that Hydromys has a faster jaw closing at the incisor, with a higher bite force at the level of the molars. The narrowing of the Hydromys jaw explains this higher lever advantage at the molars, which constitutes a good compromise between a wide gape, a reduced anterior masseteric mass, and long fiber lengths. Lever arms of the superficial and deep masseter are less favourable to force output of the mandible in Hydromys but more favourable to speed. Compared with the small input lever arm defined between the condyle and the angular process, the relatively longer mandible of Hydromys increases the speed at the expense of the output force. This unique combination of morphological features of the masticatory apparatus possibly has permitted Hydromys to become a highly successful amphibious predator in the Indo-Pacific region. © 2017 Anatomical Society.

Diagnosis of occlusal dysesthesia utilizing prefrontal hemodynamic activity with slight occlusal interference.

PubMed

Ono, Yumie; Ishikawa, Yu; Munakata, Motohiro; Shibuya, Tomoaki; Shimada, Atsushi; Miyachi, Hideo; Wake, Hiroyuki; Tamaki, Katsushi

2016-11-01

Clinical diagnosis of occlusal dysesthesia (OD), also referred to as phantom bite syndrome, is currently based on the absence of objective occlusal discrepancy despite the persistent complaint of uncomfortable bite sensation. We previously demonstrated that the subjective feeling of occlusal discomfort generated by artificial occlusal interference can be objectively evaluated using prefrontal hemodynamic activity in young healthy individuals. The aim of this study was to investigate whether dental patients with and without OD show distinct prefrontal activity during grinding behavior with an occlusal interference. Six dental patients with OD (OD group) and eight patients without OD (control group) grinded piled occlusal strips placed between their first molars and reported their perception and discomfort thresholds during continuous monitoring of prefrontal hemodynamic activity with a portable functional near-infrared spectroscopy. Although patients without OD showed the typical hemodynamic pattern of increased oxyhemoglobin and reduced deoxyhemoglobin (HHb) concentration, those with OD showed persistent incremental increases of HHb concentration that began at the loading of occlusal strips on their molars before they executed grinding. The intensities of the task-related HHb activities showed statistically significant differences between OD and control groups, particularly at channel 3, arranged over the left frontal pole cortex. When the discrimination criterion was set using the intensity values of channel 3 from both groups, the overall accuracy of the OD discrimination was 92.9%. Although physiological interpretation has yet to be elucidated, the task-related response of an increase in HHb may be a useful neuronal signature to characterize dental patients with OD.

Diagnosis of occlusal dysesthesia utilizing prefrontal hemodynamic activity with slight occlusal interference

PubMed Central

Ishikawa, Yu; Munakata, Motohiro; Shibuya, Tomoaki; Shimada, Atsushi; Miyachi, Hideo; Wake, Hiroyuki; Tamaki, Katsushi

2016-01-01

Clinical diagnosis of occlusal dysesthesia (OD), also referred to as phantom bite syndrome, is currently based on the absence of objective occlusal discrepancy despite the persistent complaint of uncomfortable bite sensation. We previously demonstrated that the subjective feeling of occlusal discomfort generated by artificial occlusal interference can be objectively evaluated using prefrontal hemodynamic activity in young healthy individuals. The aim of this study was to investigate whether dental patients with and without OD show distinct prefrontal activity during grinding behavior with an occlusal interference. Six dental patients with OD (OD group) and eight patients without OD (control group) grinded piled occlusal strips placed between their first molars and reported their perception and discomfort thresholds during continuous monitoring of prefrontal hemodynamic activity with a portable functional near‐infrared spectroscopy. Although patients without OD showed the typical hemodynamic pattern of increased oxyhemoglobin and reduced deoxyhemoglobin (HHb) concentration, those with OD showed persistent incremental increases of HHb concentration that began at the loading of occlusal strips on their molars before they executed grinding. The intensities of the task‐related HHb activities showed statistically significant differences between OD and control groups, particularly at channel 3, arranged over the left frontal pole cortex. When the discrimination criterion was set using the intensity values of channel 3 from both groups, the overall accuracy of the OD discrimination was 92.9%. Although physiological interpretation has yet to be elucidated, the task‐related response of an increase in HHb may be a useful neuronal signature to characterize dental patients with OD. PMID:29744159

3D-Finite element analysis of molars restored with endocrowns and posts during masticatory simulation.

PubMed

Dejak, Beata; Młotkowski, Andrzej

2013-12-01

The objective was to compare equivalent stresses in molars restored with endocrowns as well as posts and cores during masticatory simulation using finite element analysis. Four three-dimensional models of first mandibular molars were created: A - intact tooth; B - tooth restored by ceramic endocrown; C - tooth with FRC posts, composite core and ceramic crown; D - tooth with cast post and ceramic crown. The study was performed using finite element analysis, with contact elements. The computer simulations of mastication were conducted. The equivalent stresses of modified von Mises failure criterion (mvM) in models were calculated, Tsai-Wu index for FRC post was determinate. Maximal values of the stresses in the ceramic, cement and dentin were compared between models and to strength of the materials. Contact stresses in the cement-tissue adhesive interface around restorations were considered as well. During masticatory simulation, the lowest mvM stresses in dentin arisen in molar restored with endocrown (Model B). Maximal mvM stress values in structures of restored molar were 23% lower than in the intact tooth. The mvM stresses in the endocrown did not exceed the tensile strength of ceramic. In the molar with an FRC posts (Model C), equivalent stress values in dentin increased by 42% versus Model B. In ceramic crown of Model C the stresses were 31% higher and in the resin luting cement were 61% higher than in the tooth with endocrown. Tensile contact stresses in the adhesive cement-dentin interface around FRC posts achieved 4 times higher values than under endocrown and shear stresses increased twice. The contact stress values around the appliances were several time smaller than cement-dentin bond strength. Teeth restored by endocrowns are potentially more resistant to failure than those with FRC posts. Under physiological loads, ceramic endocrowns ideally cemented in molars should not be demaged or debonded. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

[Features of facioscapulohumeral muscular dystrophy in oral and maxillofacial region and MRI analysis of facial muscles].

PubMed

Liu, Y H; Ma, Y X; Hu, J; Gao, G D; Wu, Y K; Zhang, Z Y

2016-12-09

Objective: To investigate the manifestation of facioscapulohumeral muscular dystrophy (FSHD) in oral and maxillofacial region. Methods: A total of 12 patients diagnosed as FSHD and 20 healthy volunteers were included in the study. Their medical history was collected from these patients. The decayed missing filled teeth (DMFT), calculus index-simplified (CI-S), occlusal relationship, maximal opening of mouth and maximum bite force were recorded. The impressions were taken to measure the maximal hight of palate and the width of palate. The lateral cephalometric radiographs were also taken to measure the mandibular plane-frankfurt horizontal plane angle (MP-FH). They finally received oral and maxillofacial region MRI examination to observe the masseter muscle, medial pterygoid muscle and lateral pterygoid muscle. The data were analyzed by t -test or Wilcoxon signed ranks test. Results: There was no significant gender difference in FSHD group. The average age of treatment was (27.5 ± 8.1) years and the average age of onset was (15.7±7.5) years. Nine patients liked to eat soft foods, 4 patients had difficulties of closing eyes, 8 patients had difficulties of cheek-bulging, 10 patients showed pouty lips and 9 patients had mesio-malocclusion. DMFT (4.0±2.3), CI-S (5.8±2.1), male maximal hight of palate (20.5±2.1) mm , female maximal hight of palate (17.9±1.6) mm, MP-FH (31.8°±2.2°) of FSHD group were greater than those of the control group. Male width of palate (34.8±1.4) mm, female width of palate (33.7±1.5) mm, male maximum bite force (451.7 ± 39.0) N, female maximum bite force (326.7 ± 21.6) N, maximal opening of mouth (3.5 ± 0.4) cm of FSHD group were less than those of the control group ( P <0.05). Maxillofacial MRI showed muscle asymmetr in 11 cases of masseter and 6 cases of medial pterygoid muscle, 5 cases of lateral pterygoid, and these muscle showed mild fatty infiltration mainly concentrating in the grade 0, grade 1 and grade 2. Conclusions: The FSHD patients have poor oral hygiene, low masticatory function, limited mouth opening, high palate and narrow arch and different degree of malocclusion. The patients' masseter muscle, medial pterygoid muscles and lateral pterygoid muscles exhibit asymmetrical atrophy and fatty infiltration.

Fabrication of fixed implant prostheses using function bite impression technique (FBI technique).

PubMed

Suzuki, Yasunori; Shimpo, Hidemasa; Ohkubo, Chikahiro; Kurtz, Kenneth S

2012-10-01

The patient was partially edentulous, lacking both the first mandibular molars. The FBI and the conventional impression technique were used for the fabrication of implant-fixed prosthesis replacing the right and left molars, respectively. In the FBI technique, the definitive impression was made under occlusal force and functionally generated path (FGP) recording at the same time. The right and left occlusal contact areas were compared after completing the implant-fixed prosthesis rehabilitation. It has been suggested that accuracy of the impression and maxillomandibular registration is necessary to ensure a satisfactory long-term clinical outcome. The transfer of the exact position of the implants to the working cast is even more important because implants lack the mobility of natural teeth. There are displacement differences between implants and natural teeth under occlusal force. The FBI technique may compensate for this difference in accuracy. Using the FBI technique, a precise prosthesis could be produced by completing simultaneously the maxillomandibular registration, impression and FGP. Copyright © 2012 Japan Prosthodontic Society. All rights reserved.

The impact of temperature changes on vector-borne disease transmission: Culicoides midges and bluetongue virus.

PubMed

Brand, Samuel P C; Keeling, Matt J

2017-03-01

It is a long recognized fact that climatic variations, especially temperature, affect the life history of biting insects. This is particularly important when considering vector-borne diseases, especially in temperate regions where climatic fluctuations are large. In general, it has been found that most biological processes occur at a faster rate at higher temperatures, although not all processes change in the same manner. This differential response to temperature, often considered as a trade-off between onward transmission and vector life expectancy, leads to the total transmission potential of an infected vector being maximized at intermediate temperatures. Here we go beyond the concept of a static optimal temperature, and mathematically model how realistic temperature variation impacts transmission dynamics. We use bluetongue virus (BTV), under UK temperatures and transmitted by Culicoides midges, as a well-studied example where temperature fluctuations play a major role. We first consider an optimal temperature profile that maximizes transmission, and show that this is characterized by a warm day to maximize biting followed by cooler weather to maximize vector life expectancy. This understanding can then be related to recorded representative temperature patterns for England, the UK region which has experienced BTV cases, allowing us to infer historical transmissibility of BTV, as well as using forecasts of climate change to predict future transmissibility. Our results show that when BTV first invaded northern Europe in 2006 the cumulative transmission intensity was higher than any point in the last 50 years, although with climate change such high risks are the expected norm by 2050. Such predictions would indicate that regular BTV epizootics should be expected in the UK in the future. © 2017 The Author(s).

Fracture behavior of human molars.

PubMed

Keown, Amanda J; Lee, James J-W; Bush, Mark B

2012-12-01

Despite the durability of human teeth, which are able to withstand repeated loading while maintaining form and function, they are still susceptible to fracture. We focus here on longitudinal fracture in molar teeth-channel-like cracks that run along the enamel sidewall of the tooth between the gum line (cemento-enamel junction-CEJ) and the occlusal surface. Such fractures can often be painful and necessitate costly restorative work. The following study describes fracture experiments made on molar teeth of humans in which the molars are placed under axial compressive load using a hard indenting plate in order to induce longitudinal cracks in the enamel. Observed damage modes include fractures originating in the occlusal region ('radial-median cracks') and fractures emanating from the margin of the enamel in the region of the CEJ ('margin cracks'), as well as 'spalling' of enamel (the linking of longitudinal cracks). The loading conditions that govern fracture behavior in enamel are reported and observations made of the evolution of fracture as the load is increased. Relatively low loads were required to induce observable crack initiation-approximately 100 N for radial-median cracks and 200 N for margin cracks-both of which are less than the reported maximum biting force on a single molar tooth of several hundred Newtons. Unstable crack growth was observed to take place soon after and occurred at loads lower than those calculated by the current fracture models. Multiple cracks were observed on a single cusp, their interactions influencing crack growth behavior. The majority of the teeth tested in this study were noted to exhibit margin cracks prior to compression testing, which were apparently formed during the functional lifetime of the tooth. Such teeth were still able to withstand additional loading prior to catastrophic fracture, highlighting the remarkable damage containment capabilities of the natural tooth structure.

Camouflage treatment of skeletal Class III malocclusion with multiloop edgewise arch wire and modified Class III elastics by maxillary mini-implant anchorage.

PubMed

He, Shushu; Gao, Jinhui; Wamalwa, Peter; Wang, Yunji; Zou, Shujuan; Chen, Song

2013-07-01

To evaluate the effect of the multiloop edgewise arch wire (MEAW) technique with maxillary mini-implants in the camouflage treatment of skeletal Class III malocclusion. Twenty patients were treated with the MEAW technique and modified Class III elastics from the maxillary mini-implants. Twenty-four patients were treated with MEAW and long Class III elastics from the upper second molars as control. Lateral cephalometric radiographs were obtained and analyzed before and after treatment, and 1 year after retention. Satisfactory occlusion was established in both groups. Through principal component analysis, it could be concluded the anterior-posterior dental position, skeletal sagittal and vertical position, and upper molar vertical position changed within groups and between groups; vertical lower teeth position and Wits distance changed in the experimental group and between groups. In the experimental group, the lower incisors tipped lingually 2.7 mm and extruded 2.4 mm. The lingual inclination of the lower incisors increased 3.5°. The mandibular first molars tipped distally 9.1° and intruded 0.4 mm. Their cusps moved 3.4 mm distally. In the control group, the upper incisors proclined 3°, and the upper first molar extruded 2 mm. SN-MP increased 1.6° and S-Go/N-ME decreased 1. The MEAW technique combined with modified Class III elastics by maxillary mini-implants can effectively tip the mandibular molars distally without any extrusion and tip the lower incisors lingually with extrusion to camouflage skeletal Class III malocclusions. Clockwise rotation of the mandible and further proclination of upper incisors can be avoided. The MEAW technique and modified Class III elastics provided an appropriate treatment strategy especially for patients with high angle and open bite tendency.

Radiographic evaluation of third molar development in 6- to 24-year-olds

PubMed Central

Jung, Yun-Hoa

2014-01-01

Purpose This study investigated the developmental stages of third molars in relation to chronological age and compared third molar development according to location and gender. Materials and Methods A retrospective analysis of panoramic radiographs of 2490 patients aged between 6 and 24 years was conducted, and the developmental stages of the third molars were evaluated using the modified Demirjian's classification. The mean age, standard deviation, minimal and maximal age, and percentile distributions were recorded for each stage of development. A Mann-Whitney U test was performed to test the developmental differences in the third molars between the maxillary and mandibular arches and between genders. A linear regression analysis was used for assessing the correlation between the third molar development and chronological age. Results The developmental stages of the third molars were more advanced in the maxillary arch than the mandibular arch. Males reached the developmental stages earlier than females. The average age of the initial mineralization of the third molars was 8.57 years, and the average age at apex closure was 21.96 years. The mean age of crown completion was 14.52 and 15.04 years for the maxillary and the mandibular third molars, respectively. Conclusion The developmental stages of the third molars clearly showed a strong correlation with age. The third molars developed earlier in the upper arch than the lower arch; further, they developed earlier in males than in females. PMID:25279338

Correlation between clinical and radiographic findings on the occurrence of furcation involvement in patients with periodontitis.

PubMed

Gusmão, Estela Santos; Picarte, Ana Carolina Lessa Cavalcanti; Ben Barbosa, Maria Bernadete Cavalcanti; Rösing, Cassiano Kuchenbecker; Cimoes, Renata

2014-01-01

Aim : The aim of the present study was to determine the occurrence of furcation involvement in the molars of patients with chronic periodontitis and correlate clinical and radiographic findings. Seventy subjects aged 35-69 years enrolled for treatment at a periodontics specialization program in Pernambuco, Brazil (EAP-SCDP-ABO/PE) participated in the study, comprising a total of 350 molars examined. The clinical diagnosis of furcation involvement was performed with a horizontal Nabers probe, whereas the radiographic examination was performed with periapical and bite-wing radiographs. The images were analyzed with an X-ray viewer at 3× magnification. The Chi-square test was used, with the level of significance set at 5%. A total of 64.5% individuals presented with furcation involvement, 43.1% of whom had degree II furcation. A significant association (P = 0.0060) was found between tooth type and frequency of furcation involvement. The first lower and upper molars were affected in 64.5 and 58.5% of cases, respectively. Adequate agreement (0.65) was observed between the clinical and radiographic findings. Taking into consideration the method employed and the results obtained, it may be concluded that the clinical and radiographic examinations performed are effective tools for diagnosing furcation involvement in teeth affected with periodontal disease.

Human dental age estimation combining third molar(s) development and tooth morphological age predictors.

PubMed

Thevissen, P W; Galiti, D; Willems, G

2012-11-01

In the subadult age group, third molar development, as well as age-related morphological tooth information can be observed on panoramic radiographs. The aim of present study was to combine, in subadults, panoramic radiographic data based on developmental stages of third molar(s) and morphological measurements from permanent teeth, in order to evaluate its added age-predicting performances. In the age range between 15 and 23 years, 25 gender-specific radiographs were collected within each age category of 1 year. Third molar development was classified and registered according the 10-point staging and scoring technique proposed by Gleiser and Hunt (1955), modified by Köhler (1994). The Kvaal (1995) measuring technique was applied on the indicated teeth from the individuals' left side. Linear regression models with age as response and third molar-scored stages as explanatory variables were developed, and morphological measurements from permanent teeth were added. From the models, determination coefficients (R (2)) and root-mean-square errors (RMSE) were calculated. Maximal-added age information was reported as a 6 % R² increase and a 0.10-year decrease of RMSE. Forensic dental age estimations on panoramic radiographic data in the subadult group (15-23 year) should only be based on third molar development.

Optimal Repellent Usage to Combat Dengue Fever.

PubMed

Dorsett, Chasity; Oh, Hyunju; Paulemond, Marie Laura; Rychtář, Jan

2016-05-01

Dengue fever is one of the most important vector-borne diseases. It is transmitted by Aedes Stegomyia aegypti, and one of the most effective strategies to combat the disease is the reduction of exposure to bites of these mosquitoes. In this paper, we present a game-theoretical model in which individuals choose their own level of protection against mosquito bites in order to maximize their own benefits, effectively balancing the cost of protection and the risk of contracting the dengue fever. We find that even when the usage of protection is strictly voluntary, as soon as the cost of protection is about 10,000 times less than the cost of contracting dengue fever, the optimal level of protection will be within 5 % of the level needed for herd immunity.

The effectiveness of pendulum, K-loop, and distal jet distalization techniques in growing children and its effects on anchor unit: A comparative study.

PubMed

Marure, Pravinkumar S; Patil, Raju Umaji; Reddy, Sumitra; Prakash, Amit; Kshetrimayum, Nillachandra; Shukla, Rajeevkumar

2016-01-01

A common strategy to correct Class II malocclusions using a nonextraction protocol in children is to move the maxillary molars distally using molar distalization appliances, which usually derive their anchorage from maxillary premolars, causing mesialization of premolars and protrusion of incisors. To evaluate the skeletal, dental and soft tissue changes produced by three different distalizing appliances, namely, pendulum, K-loop, and distal jet appliances. Sixty-six children of mean age 14.13 years requiring molar distalization were divided into three groups: Group I (pendulum appliance), Group II (K-loop), and Group III (distal jet). Lateral cephalometric films were taken before and after 5 months of molar distalization and following cephalometric parameters were used to assess the effects of maxillary molar distalization, namely, anteroposterior skeletal (SNA/SNB/ANB), vertical skeletal (face height ratio/Frankfort-mandibular plane [FMA]/angle formed between Maxillary plane & Mandibular plane (MM)), interdental (overjet/overbite), maxillary dentoalveolar, and soft tissue parameters. There was no significant age difference between the three groups. In overall treatment changes among the three groups, the Anteroposterior skeletal changes were not statistically significant, vertically FMA angle increased by 1.79° ± 2.25° and overbite reduced by 2.38 ± 1.83 mm. The maxillary first molars were distalized by an average of 4.70 ± 3.01 mm (Upper 6 [U6] to pterygoid vertical [PTV]). The maxillary central incisor labial tipping increased to an average of 1.61 ± 2.73 mm and cant of upper lip increased by 3.40° ± 5.88° are statistically significant (P < 0.05). All three distalization techniques in growing children produced significant effects on anchor unit. There was an increase in FMA angle, significant bite opening, proclination of the maxillary incisors and increase in the cant of the upper lip.

Analysis of intra-arch and interarch measurements from digital models with 2 impression materials and a modeling process based on cone-beam computed tomography.

PubMed

White, Aaron J; Fallis, Drew W; Vandewalle, Kraig S

2010-04-01

Study models are an essential part of an orthodontic record. Digital models are now available. One option for generating a digital model is cone-beam computed tomography (CBCT) scanning of orthodontic impressions and bite registrations. However, the accuracy of digital measurements from models generated by this method has yet to be thoroughly evaluated. A plastic typodont was modified with reference points for standardized intra-arch and interarch measurements, and 16 sets of maxillary and mandibular vinylpolysiloxane and alginate impressions were made. A copper wax-bite registration was made with the typodont in maximum intercuspal position to accompany each set of impressions. The impressions were shipped to OrthoProofUSA (Albuquerque, NM), where digital orthodontic models were generated via CBCT. Intra-arch and interarch measurements were made directly on the typodont with electronic digital calipers and on the digital models by using OrthoProofUSA's proprietary DigiModel software. Percentage differences from the typodont of all intra-arch measurements in the alginate and vinylpolysiloxane groups were low, from 0.1% to 0.7%. Statistical analysis of the intra-arch percentage differences from the typodont of the alginate and vinylpolysiloxane groups had a statistically significant difference between the groups only for maxillary intermolar width. However, because of the small percentage differences, this was not considered clinically significant for orthodontic measurements. Percentage differences from the typodont of all interarch measurements in the alginate and vinylpolysiloxane groups were much higher, from 3.3% to 10.7%. Statistical analysis of the interarch percentage differences from the typodont of the alginate and vinylpolysiloxane groups showed statistically significant differences between the groups in both the maxillary right canine to mandibular right canine (alginate with a lower percentage difference than vinylpolysiloxane) and the maxillary left second molar to mandibular left second molar (alginate with a greater percentage difference than vinylpolysiloxane) segments. This difference, ranging from 0.24 to 0.72 mm, is clinically significant. In this study, digital orthodontic models from CBCT scans of alginate and vinylpolysiloxane impressions provided a dimensionally accurate representation of intra-arch relationships for orthodontic evaluation. However, the use of copper wax-bite registrations in this CBCT-based process did not result in an accurate digital representation of interarch relationships. Copyright (c) 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Differences of isolated dental stem cells dependent on donor age and consequences for autologous tooth replacement.

PubMed

Kellner, Manuela; Steindorff, Marina M; Strempel, Jürgen F; Winkel, Andreas; Kühnel, Mark P; Stiesch, Meike

2014-06-01

Autologous therapy via stem cell-based tissue regeneration is an aim to rebuild natural teeth. One option is the use of adult stem cells from the dental pulp (DPSCs), which have been shown to differentiate into several types of tissue in vitro and in vivo, especially into tooth-like structures. DPSCs are mainly isolated from the dental pulp of third molars routinely extracted for orthodontic reasons. Due to the extraction of third molars at various phases of life, DPSCs are isolated at different developmental stages of the tooth. The present study addressed the question whether DPSCs from patients of different ages were similar in their growth characteristics with respect to the stage of tooth development. Therefore DPSCs from third molars of 12-30 year-old patients were extracted, and growth characteristics, e.g. doubling time and maximal cell division potential were analysed. In addition, pulp and hard dental material weight were recorded. Irrespective of the age of patients almost all isolated cells reached 40-60 generations with no correlation between maximal cell division potential and patient age. Cells from patients <22 years showed a significantly faster doubling time than the cells from patients ≥22 years. The age of patients at the time of stem cell isolation is not a crucial factor concerning maximal cell division potential, but does have an impact on the doubling time. However, differences in individuals regarding growth characteristics were more pronounced than age-dependent differences. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sexual dimorphism in bite performance drives morphological variation in chameleons.

PubMed

da Silva, Jessica M; Herrel, Anthony; Measey, G John; Tolley, Krystal A

2014-01-01

Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and constraining performance.

Sexual Dimorphism in Bite Performance Drives Morphological Variation in Chameleons

PubMed Central

da Silva, Jessica M.; Herrel, Anthony; Measey, G. John; Tolley, Krystal A.

2014-01-01

Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal’s foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal’s performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and constraining performance. PMID:24475183

[Comparative study of expression of homeobox gene Msx-1, Msx-2 mRNA during the hard tissue formation of mouse tooth development].

PubMed

Wang, Y; Wang, J; Gao, Y

2001-07-01

To observe and compare the expression pattern of Msx-1, Msx-2 mRNA during the different stages of hard tissue formation in the first mandibular molar of mouse and investigate the relationship between the two genes. First mandibular molar germs from 1, 3, 7 and 14-days old mouse were separated and reverse transcription-polymerase chain reaction was performed on the total RNA of them using Msx-1, Msx-2 specific primers separately. Expression of both genes were detected during the different stages of hard tissue formation in the mouse first mandibular molars, but there was some interesting differences in the quantitiy between the two genes. Msx-1 transcripts appeared at the 1 day postnatally, and increase through 3 day, 7 day, then maximally expressed at 14 days postnatally; while Msx-2 mRNA was seen and expressed maximally at the 3 days postnatally, then there was a gradual reduction at 7 days, and 14 days postnatally. The homeobox gene Msx-1, Msx-2 may play a role in the events of the hard tissue formation. The complementary expression pattern of them during the specific stage of hard tissue formation indicates that there may be some functional redundancy between them during the biomineralization.

Comparative effect of tube drain on post operative inflammatory complications of impacted mandibular third molar surgery College Hospital, Ibadan, Nigeria.

PubMed

Obimakinde, O S; Fasola, A O; Arotiba, J T; Okoje, V N; Obiechina, A E

2010-09-01

Swelling, pain and trismus are acute reversible inflammatory complications of impacted mandibular third molar (M3) surgery. They contribute to the deterioration of quality of life and loss of several useful working hours. This study aimed to investigate whether the use of a surgical drain following M3 surgery can minimise these inflammatory complications. Eighty consecutive patients who gave consent were enrolled into the study. Patients were assigned into two groups (drain and no drain) by systematic sampling method which was modified to ensure matching of patients by age, sex and spatial relationship of the impacted mandibular third molar. The patients in the drain group (n=40) had a Foley's catheter drain inserted into the wound after the surgical procedure while the patients in the no drain group (n=40) had their wound closed without the use of drain. All patients had primary wound closure with 3.0 black silk sutures after the procedure. Demographic data, cheek dimension and maximal mouth opening were recorded before the procedure. Pain, swelling and trismus were evaluated in the two groups at 24 hours, 48 hours and 7th day after surgery. Post operative swelling and visual analogue scale score for pain were comparatively lesser in the drain group patients. The maximal interincisal distance was also more in the drain group patients. The findings from this study indicated that there is a significant benefit of using a surgical drain in minimising postoperative oedema, pain and trismus following surgical removal of impacted mandibular third molar.

Evaluation of the occlusal contact of crowns fabricated with the bite impression method.

PubMed

Makino, Sachi; Okada, Daizo; Shin, Chiharu; Ogura, Reiko; Ikeda, Masaomi; Miura, Hiroyuki

2013-09-30

In prosthodontic treatment, reconstruction of a proper occlusal contact relationship is very important as well as reconstruction of a proper interproximal relationship and marginal fitness. Unfortunately, occlusal relationships are sometimes lost in the process of occlusal adjustment of crowns. The purpose of this study was to compare the occlusal contacts of single crown fabricated by two different types of impression techniques. Nine subjects, whose molars required treatment with crown restoration, were enrolled in this study. Full cast crowns were fabricated using two types of impression techniques: the conventional impression method (CIM) and the bite impression method (BIM). The occlusal contacts of crowns were precisely evaluated at the following stages: after occlusal adjustment on the articulator (Step 0), before occlusal adjustment in the mouth (Step 1), after occlusal adjustment at the intercuspal position (Step 2), and after occlusal adjustment during lateral and protrusive excursions (Step 3). The number of occlusal contacts of the crowns on the functional cusps fabricated with BIM was significantly greater than that with CIM after occlusal adjustment. For this reason, the crowns fabricated with BIM might have a more functionally desirable occlusal surface compared to the crowns fabricated with CIM.

New Design for an Adjustable Cise Space Maintainer

PubMed Central

2018-01-01

Objective The aim of this study is to present a new adjustable Cise space maintainer for preventive orthodontic applications. Methods Stainless steel based new design consists of six main components. In order to understand the major displacement and stress fields, structural analysis for the design is considered by using finite element method. Results Similar to major displacement at y-axis, critical stresses σx and τxy possess a linear distribution with constant increasing. Additionally, strain energy density (SED) plays an important role to determine critical biting load capacity. Conclusion Structural analysis shows that the space maintainer is stable and is used for maintaining and/or regaining the space which arouses early loss of molar tooth. PMID:29854764

Dental compensation for moderate Class III with vertical growth pattern by extraction of the lower second molars.

PubMed

Jacobs, Collin; Jacobs-Müller, Claudia; Hoffmann, Viviana; Meila, Dan; Erbe, Christina; Krieger, Elena; Wehrbein, Heiner

2012-01-01

Analysis of the effects and side effects of treatment of patients with moderate skeletal Class III and vertical growth pattern by means of extraction of the second molars in the lower jaw. A total of 20 patients with a mean age of 12.9 years were examined retrospectively. Inclusion criteria consisted of a Wits value of 0 to -5, a posterior growth pattern of the mandible (Hasund analysis), an overjet of -2 to 1 mm, and an overbite of 0 to -3 mm. Treatment was performed using a straight-wire appliance. As part of the treatment, the lower second molars were extracted and Class III elastics attached. Cephalograms and orthopantomograms taken before and after treatment were used for evaluation. Treatment resulted in a significant change in the mean overjet from 0.5 mm to 2.1 mm and the attainment of a positive mean overbite of -1.0 mm to 0.9 mm. The occlusal plane rotated anteriorly from 18.8° to 13.7°. The skeletal parameters showed a change in the Wits value from -3.3 mm to -1.4 mm and an anterior mandibular rotation (ML-NSL 35.5° vs. 32.0°). The soft tissues revealed an increase in the distance between the lower lip and the "esthetic line" to the posterior (-2.0 mm vs. -3.9 mm). Dental compensation of moderate skeletal Class III with a tendency to an anterior open bite with vertical growth pattern by extracting the lower second molars, combined with Class III elastics, resulted in an anterior rotation of the occlusal plane and mandible. Eighteen of 20 patients achieved a physiological overjet and positive overbite. A prerequisite for this therapy is the presence of lower wisdom teeth; a potential side effect is elongation of the upper second molars.

Relationship between masticatory function and internal structure of the mandible based on computed tomography findings.

PubMed

Sato, Hidemasa; Kawamura, Akira; Yamaguchi, Masaru; Kasai, Kazutaka

2005-12-01

The purposes of this study were to investigate bone mineral density as a part of bone construction in human skulls and to examine the relationship between dentofacial morphology and masticatory function by using computed tomography (CT) findings. Changes in bone mineral density in the mandible because of loss of masticatory function were tested in rats by experimentally producing an environment that inhibited mastication by the molars. Data for the human study were obtained from 27 modern male Japanese skulls (mean age, 28 years) from the University of Tokyo. Cortical bone thickness (CBT) and CT value (CV) were measured by each CT scan of the first and molars. For the animal study, a metal cap was inserted between the maxillary and mandibular incisors to prevent the molars from biting in 6-week-old male Wistar rats. The rats were killed after 2, 4, or 6 weeks, and bone mineral density was measured in cancellous and cortical bone equivalent to the first molar region by using peripheral quantitative computed tomography. In the human skull study, significant negative correlations were observed between CV in the regions of the buccal side of the second molar and the angle between the Frankfort horizontal and mandibular planes. Significant negative correlations were also observed between the gonial angle and CV in the buccal and basal sides. In the animal study, cancellous bone mineral density began to decline 4 weeks after the start of the experiment in the masticatory hypofunction group compared with the control group. By week 6, cancellous bone density had declined by 11.6% on the buccal side, 16.7% on the lingual side, 12.3% at the bifurcation of the root, and 38.1% at the root apex. Cortical bone density declined by 8% to 12% on the lingual side. The results support our hypothesis that a functional adaptive response by the mandible to mechanical stress resulting from mastication occurs not only in the muscle insertion area, but also in mandibular alveolar bone in the molar region.

Oral Health-Related Quality of Life Following Third Molar Surgery in an African Population

PubMed Central

Ibikunle, Adebayo Aremu; Adeyemo, Wasiu Lanre

2017-01-01

Introduction: Surgical extraction of impacted mandibular third molars is often associated with sequelae such as postoperative pain, facial edema, and limitation in mouth opening ability. These sequelae may result in changes in the patients’ lifestyle and quality of life (QoL). Aim: The aim of this study was to evaluate the effect of surgical extraction of impacted mandibular third molars on patients’ QoL in the immediate postoperative period (7 days). Materials and Methods: Ethical approval for this study was obtained from the Health Research and Ethics committee of the Lagos University Teaching Hospital. A total of 124 individuals with impacted mandibular third molars, who satisfied the inclusion criteria and consented to participate in this study, were included. The Oral Health Impact Profile-14 (OHIP-14) QoL questionnaire was used to assess QoL. QoL was assessed preoperatively (baseline) and on postoperative days (PODs) 1, 3, and 7. Maximal interincisal mouth opening, facial width, and pain were also reviewed at all evaluation points. Data analysis was done using the Statistical Package for Social Sciences (SPSS) for Windows (version 16.0, Chicago, IL, USA). Results: A total of 124 individuals were included in the final analysis. An age range of 18–51 years with a mean (±standard deviation) of 28.5 (7.4) years was observed. A male to female ratio of 1:1.5 was observed. The most frequently encountered type of impaction was the mesioangular impaction 51 (41.1%) and recurrent pericoronitis was the principal reason for extraction 53 (42.7%). The severity of the sequelae (pain, trismus, and facial edema) was maximal on the first POD. Patients’ overall QoL deteriorated sharply on the first POD and subsequently improved. Conclusion: Surgical extraction of mandibular third molars is associated with worsening of patients’ postoperative QoL in the immediate postoperative period. Prospective patients should be informed about this, and ways of reducing this untoward effect should be explored. PMID:29326504

Modelling the impact of the long-term use of insecticide-treated bed nets on Anopheles mosquito biting time.

PubMed

Ferreira, Claudia P; Lyra, Silas P; Azevedo, Franciane; Greenhalgh, David; Massad, Eduardo

2017-09-15

Evidence of changing in biting and resting behaviour of the main malaria vectors has been mounting up in recent years as a result of selective pressure by the widespread and long-term use of insecticide-treated bed nets (ITNs), and indoor residual spraying. The impact of resistance behaviour on malaria intervention efficacy has important implications for the epidemiology and malaria control programmes. In this context, a theoretical framework is presented to understand the mechanisms determining the evolution of feeding behaviour under the pressure of use of ITNs. An agent-based stochastic model simulates the impact of insecticide-treated bed nets on mosquito fitness by reducing the biting rates, as well as increasing mortality rates. The model also incorporates a heritability function that provides the necessary genetic plasticity upon which natural selection would act to maximize the fitness under the pressure of the control strategy. The asymptotic equilibrium distribution of mosquito population versus biting time is shown for several daily uses of ITNs, and the expected disruptive selection on this mosquito trait is observed in the simulations. The relative fitness of strains that bite at much earlier time with respect to the wild strains, when a threshold of about 50% of ITNs coverage highlights the hypothesis of a behaviour selection. A sensitivity analysis has shown that the top three parameters that play a dominant role on the mosquito fitness are the proportion of individuals using bed nets and its effectiveness, the impact of bed nets on mosquito oviposition, and the mosquito genetic plasticity related to changing in biting time. By taking the evolutionary aspect into account, the model was able to show that the long-term use of ITNs, although representing an undisputed success in reducing malaria incidence and mortality in many affected areas, is not free of undesirable side effects. From the evolutionary point of view of the parasite virulence, it should be expected that plasmodium parasites would be under pressure to reduce their virulence. This speculative hypothesis can eventually be demonstrated in the medium to long-term use of ITNs.

In vivo bone strain in the mandibular corpus of Sapajus during a range of oral food processing behaviors.

PubMed

Ross, Callum F; Iriarte-Diaz, Jose; Reed, David A; Stewart, Thomas A; Taylor, Andrea B

2016-09-01

It has been hypothesized that mandibular corpus morphology of primates is related to the material properties of the foods that they chew. However, chewing foods with different material properties is accompanied by low levels of variation in mandibular strain patterns in macaques. We hypothesized that if variation in primate mandible form reflects adaptations to feeding on foods with different material and geometric properties, then this variation will be driven primarily by differences in oral food processing behavior rather than differences in chewing per se. To test this hypothesis, we recorded in vivo bone strain data from the lateral and medial surfaces of the mandibular corpus during complete feeding sequences in three adult male Sapajus as they fed on foods with a range of sizes and material properties. We assessed whether variation in mandibular corpus strain regimes is associated with variation in feeding behaviors and/or chewing on different foods, and we quantified the relative variation in mandibular corpus strain regimes associated with chewing on foods of different material properties versus a range of oral food processing behaviors (incisor, premolar, and molar biting; pulling on incisors; mastication). Feeding behavior had a significant effect on mandibular corpus strain regimes, as did chewing side and the cycle number in a feeding sequence. However, food type had weaker effects and usually only through interaction effects with chewing side and/or cycle type. Strain regimes varied most across different chew sides, then across different behaviors, and lastly between mastication cycles on different foods. Strain magnitudes associated with premolar, molar, and incisor biting were larger than those recorded during mastication. These data suggest that intra- and inter-specific variation in mandible morphology is a trade-off between performance requirements of different oral food processing behaviors and of variation in chewing side, with direct effects of food type being less important. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of horizontal tooth wear in maxillary anterior teeth from five to 18 years of age.

PubMed

Nyström, M; Könönen, M; Alaluusua, S; Evälahti, M; Vartiovaara, J

1990-11-01

Sizes of horizontal wear facets of maxillary anterior teeth were studied longitudinally from the primary dentition at age five to the young adult dentition at the age of 18 years. By a planimetric method, we calculated the wear areas on dental casts taken at the ages of five, ten, 14, and 18 years from the dentition of 39 healthy, orthodontically untreated subjects with good morphological occlusion. For young adults, we also studied the association between the amount of wear and reported parafunctions, maximal bite force, salivary buffer capacity, salivary flow rate, and some cephalometric variables. Size of wear facets on all anterior teeth increased with age. Significant correlations were found between the total wear areas of the six anterior primary teeth at five years of age and those of their permanent successors at age 14 (r = 0.44) and 18 (r = 0.39). For an individual, tooth wear at five years of age was, however, of low predictive value for tooth wear in young adulthood, whereas tooth wear at 14 years of age predicted it well (r = 0.89). Highest correlations between tooth wear and background factors at 18 years of age were found for maximal anterior bite force (r = 0.44) and for the size of the gonial angle (r = -0.31). Wear of anterior teeth was not associated with reported parafunctions in young adulthood.

Assessment of vector/host contact: comparison of animal-baited traps and UV-light/suction trap for collecting Culicoides biting midges (Diptera: Ceratopogonidae), vectors of Orbiviruses

PubMed Central

2011-01-01

Background The emergence and massive spread of bluetongue in Western Europe during 2006-2008 had disastrous consequences for sheep and cattle production and confirmed the ability of Palaearctic Culicoides (Diptera: Ceratopogonidae) to transmit the virus. Some aspects of Culicoides ecology, especially host-seeking and feeding behaviors, remain insufficiently described due to the difficulty of collecting them directly on a bait animal, the most reliable method to evaluate biting rates. Our aim was to compare typical animal-baited traps (drop trap and direct aspiration) to both a new sticky cover trap and a UV-light/suction trap (the most commonly used method to collect Culicoides). Methods/results Collections were made from 1.45 hours before sunset to 1.45 hours after sunset in June/July 2009 at an experimental sheep farm (INRA, Nouzilly, Western France), with 3 replicates of a 4 sites × 4 traps randomized Latin square using one sheep per site. Collected Culicoides individuals were sorted morphologically to species, sex and physiological stages for females. Sibling species were identified using a molecular assay. A total of 534 Culicoides belonging to 17 species was collected. Abundance was maximal in the drop trap (232 females and 4 males from 10 species) whereas the diversity was the highest in the UV-light/suction trap (136 females and 5 males from 15 species). Significant between-trap differences abundance and parity rates were observed. Conclusions Only the direct aspiration collected exclusively host-seeking females, despite a concern that human manipulation may influence estimation of the biting rate. The sticky cover trap assessed accurately the biting rate of abundant species even if it might act as an interception trap. The drop trap collected the highest abundance of Culicoides and may have caught individuals not attracted by sheep but by its structure. Finally, abundances obtained using the UV-light/suction trap did not estimate accurately Culicoides biting rate. PMID:21707980

Specific Diurnal EMG Activity Pattern Observed in Occlusal Collapse Patients: Relationship between Diurnal Bruxism and Tooth Loss Progression

PubMed Central

Kawakami, Shigehisa; Kumazaki, Yohei; Manda, Yosuke; Oki, Kazuhiro; Minagi, Shogo

2014-01-01

Aim The role of parafunctional masticatory muscle activity in tooth loss has not been fully clarified. This study aimed to reveal the characteristic activity of masseter muscles in bite collapse patients while awake and asleep. Materials and Methods Six progressive bite collapse patients (PBC group), six age- and gender-matched control subjects (MC group), and six young control subjects (YC group) were enrolled. Electromyograms (EMG) of the masseter muscles were continuously recorded with an ambulatory EMG recorder while patients were awake and asleep. Diurnal and nocturnal parafunctional EMG activity was classified as phasic, tonic, or mixed using an EMG threshold of 20% maximal voluntary clenching. Results Highly extended diurnal phasic activity was observed only in the PBC group. The three groups had significantly different mean diurnal phasic episodes per hour, with 13.29±7.18 per hour in the PBC group, 0.95±0.97 per hour in the MC group, and 0.87±0.98 per hour in the YC group (p<0.01). ROC curve analysis suggested that the number of diurnal phasic episodes might be used to predict bite collapsing tooth loss. Conclusion Extensive bite loss might be related to diurnal masticatory muscle parafunction but not to parafunction during sleep. Clinical Relevance: Scientific rationale for study Although mandibular parafunction has been implicated in stomatognathic system breakdown, a causal relationship has not been established because scientific modalities to evaluate parafunctional activity have been lacking. Principal findings This study used a newly developed EMG recording system that evaluates masseter muscle activity throughout the day. Our results challenge the stereotypical idea of nocturnal bruxism as a strong destructive force. We found that diurnal phasic masticatory muscle activity was most characteristic in patients with progressive bite collapse. Practical implications The incidence of diurnal phasic contractions could be used for the prognostic evaluation of stomatognathic system stability. PMID:25010348

[Effects of breast-feeding duration, bottle-feeding duration and oral habits on the occlusal characteristics of primary dentition].

PubMed

Chen, X X; Xia, B; Ge, L H; Yuan, J W

2016-12-18

To assess the effects of breast-feeding duration, bottle-feeding duration and oral habits on the occlusal characteristics of primary dentition in 3-6-year-old children in Beijing. This cross sectional study was conducted via an examination of the occlusal characteristics of 734 children combined with a questionnaire completed by their parents/guardians. The examination was performed by a single, previously calibrated examiner and the following variables were evaluated: presence or absence of deep overbite, open bite, anterior cross bite, posterior cross bite, deep overjet, terminal plane relationship of the second primary molar, primary canine relationship, crowding and spacing. Univariate analysis and multiple Logistic regressions were applied to analyze the associations. It was found that a short duration of breast-feeding (never or ≤6 months) was directly associated with posterior cross bite (OR=3.13, 95%CI=1.11-8.82, P=0.031) and no maxillary space (OR=1.63, 95%CI=1.23-2.98, P=0.038). In children breast-fed for ≤6 months, the probability of developing pacifier-sucking habits was 4 times that for those breast-fed for >6 months (OR=4.21, 95%CI=1.85-9.60, P=0.000 2). The children who were bottle-fed for over 18 months had a 1.45-fold higher risk of nonmesial step occlusion and a 1.43-fold higher risk of class II canine relationship compared with those who were bottle-fed for 6-18 months. Non-nutritive sucking habits were also found to affect occlusion: a prolonged digit-sucking habit increased the probability of an anterior open bite, while a pacifier-sucking habit was associated with excessive overjet and absence of lower arch developmental space. Tongue-thrust habit was associated with anterior open bite (OR=4.21, 95%CI=1.85-9.60, P=0.000 2) and posterior cross bite (OR=7.24, 95%CI=1.30-40.13, P=0.024). Lower lip sucking habit was associated with deep overjet and had a negative association with class III canine relationship. Unilateral chewing was associated with spacing in mandibular (OR=1.57, 95%CI=1.03-2.41, P=0.037). Mouth breathing was associated with chronic rhinitis and adenoidal hypertrophy and had an association with spacing in maxillary. The chi-square test did not indicate a statistically significant association between upper lip sucking habit and any occlusal characteristics. Breast-feeding duration was shown to be associated with the prevalence of posterior crossbite, or no maxillary space in the deciduous dentition and development of a pacifier-sucking habit. Children who had a longer duration of bottle-feeding were more likely to develop class II canine relationship. Children who had an oral habit were more likely to develop abnormal occlusal characteristics.

Adaptation of BAp crystal orientation to stress distribution in rat mandible during bone growth

NASA Astrophysics Data System (ADS)

Nakano, T.; Fujitani, W.; Ishimoto, T.; Umakoshi, Y.

2009-05-01

Biological apatite (BAp) c-axis orientation strongly depends on stress distribution in vivo and tends to align along the principal stress direction in bones. Dentulous mandible is subjected to a complicated stress condition in vivo during chewing but few studies have been carried out on the BAp c-axis orientation; so the adaptation of BAp crystal orientation to stress distribution was examined in rat dentulous mandible during bone growth and mastication. Female SD rats 4 to 14 weeks old were prepared, and the bone mineral density (BMD) and BAp crystal orientation were analyzed in a cross-section of mandible across the first molar focusing on two positions: separated from and just under the tooth root on the same cross-section perpendicular to the mesiodistal axis. The degree of BAp orientation was analyzed by a microbeam X-ray diffractometer using Cu-Kα radiation equipped with a detector of curved one-dimensional PSPC and two-dimensional PSPC in the reflection and transmission optics, respectively. BMD quickly increased during bone growth up to 14 weeks, although it was independent of the position from the tooth root. In contrast, BAp crystal orientation strongly depended on the age and the position from the tooth root, even in the same cross-section and direction, especially along the mesiodistal and the biting axes. With increased biting stress during bone growth, the degree of BAp orientation increased along the mesiodistal axis in a position separated from the tooth root more than that near the tooth root. In contrast, BAp preferential alignment clearly appeared along the biting axis near the tooth root. We conclude that BAp orientation rather than BMD sensitively adapts to local stress distribution, especially from the chewing stress in vivo in the mandible.

Severe maxillary osteomyelitis in a Gray Wolf (Canis lupus)

USGS Publications Warehouse

Barber-Meyer, Shannon

2012-01-01

Dental injuries to or abnormalities in functionally important teeth and associated bones in predators may significantly reduce the ability to kill and consume prey (Lazar et al. 2009). This impairment is likely exacerbated in coursing predators, such as Gray Wolves, that bite and hold onto fleeing and kicking prey with their teeth. Damage to carnassials (upper fourth premolar, P4, and lower first molar, M1) and associated bones in Gray Wolves may especially inhibit the consumption of prey because these teeth slice meat and crush bone. Here I report maxillary osteomyelitis involving the carnassials in a wild Gray Wolf from northeastern Minnesota of such severity that I hypothesize it ultimately caused the Gray Wolf to starve to death.

Three-dimensional computer-assisted study model analysis of long-term oral-appliance wear. Part 2. Side effects of oral appliances in obstructive sleep apnea patients.

PubMed

Chen, Hui; Lowe, Alan A; de Almeida, Fernanda Riberiro; Fleetham, John A; Wang, Bangkang

2008-09-01

Oral appliances (OAs) are widely prescribed for the treatment of obstructive sleep apnea (OSA). The occlusal changes that occur after long term OA treatment have not been well described based on detailed computerized three-dimensional (3D) assessment. Seventy patients with OSA (mean age, 50.0 years) who had been treated with an OA were identified for this study. A MicroScribe-3DX dental study model analysis system was used to make 3D measurements on baseline and follow-up (88.4 +/- 26.7 months) study models. The following dental measurements showed significant changes (P <0.05) with long-term use of an OA: mandibular arch width increased more than maxillary arch width, crowding decreased in both arches, the curve of Spee became flat in the premolar area, the mandibular canine to second molar segment moved forward in relation to the maxillary arch, the bite opened and the overjet decreased except in some molar areas. A variety of occlusal changes occur with long-term OA treatment for OSA. The changes could be regarded as either adverse or beneficial depending upon the baseline characteristics.

Etherification of biodiesel-derived glycerol with ethanol for fuel formulation over sulfonic modified catalysts.

PubMed

Melero, Juan A; Vicente, Gemma; Paniagua, Marta; Morales, Gabriel; Muñoz, Patricia

2012-01-01

The present study is focused on the etherification of biodiesel-derived glycerol with anhydrous ethanol over arenesulfonic acid-functionalized mesostructured silicas to produce ethyl ethers of glycerol that can be used as gasoline or diesel fuel biocomponents. Within the studied range, the best conditions to maximize glycerol conversion and yield towards ethyl-glycerols are: T=200 °C, ethanol/glycerol molar ratio=15/1, and catalyst loading=19 wt%. Under these reaction conditions, 74% glycerol conversion and 42% yield to ethyl ethers have been achieved after 4 h of reaction but with a significant presence of glycerol by-products. In contrast, lower reaction temperatures (T=160 °C) and moderate catalyst loading (14 wt%) in presence of a high ethanol concentration (ethanol/glycerol molar ratio=15/1) are necessary to avoid the formation of glycerol by-products and maximize ethyl-glycerols selectivity. Interestingly, a close catalytic performance to that achieved using high purity glycerol has been obtained with low-grade water-containing glycerol. Copyright © 2011 Elsevier Ltd. All rights reserved.

Functional morphology and biomechanics of the tongue-bite apparatus in salmonid and osteoglossomorph fishes

PubMed Central

Camp, Ariel L; Konow, Nicolai; Sanford, Christopher P J

2009-01-01

The tongue-bite apparatus and its associated musculoskeletal elements of the pectoral girdle and neurocranium form the structural basis of raking, a unique prey-processing behaviour in salmonid and osteoglossomorph fishes. Using a quantitative approach, the functional osteology and myology of this system were compared between representatives of each lineage, i.e. the salmonid Salvelinus fontinalis (N =10) and the osteoglossomorph Chitala ornata(N = 8). Divergence was found in the morphology of the novel cleithrobranchial ligament, which potentially relates to kinematic differences between the raking lineage representatives. Salvelinus had greater anatomical cross-sectional areas of the epaxial, hypaxial and protractor hyoideus muscles, whereas Chitala had greater sternohyoideus and adductor mandibulae mass. Two osteology-based biomechanical models (a third-order lever for neurocranial elevation and a modified four-bar linkage for hyoid retraction) showed divergent force/velocity priorities in the study taxa. Salvelinus maximizes both force (via powerful cranial muscles) and velocity (through mechanical amplification) during raking. In contrast, Chitala has relatively low muscle force but more efficient force transmission through both mechanisms compared with Salvelinus. It remains unclear if and how behavioural modulation and specializations in the post-cranial anatomy may affect the force/velocity trade-offs in Chitala. Further studies of tongue-bite apparatus morphology and biomechanics in a broader species range may help to clarify the role that osteology and myology play in the evolution of behavioural diversity. PMID:19438765

Biomechanical Assessment of Restored Mandibular Molar by Endocrown in Comparison to a Glass Fiber Post-Retained Conventional Crown: 3D Finite Element Analysis.

PubMed

Helal, Mohammed Abu; Wang, Zhigang

2017-10-25

To compare equivalent and contact stresses in a mandibular molar restored by all-ceramic crowns through two methods: ceramic endocrowns and ceramic crowns supported by fiber-reinforced composite (FRC) posts and core, by using 3D finite element analysis during normal masticatory load. Three 3D models of a mandibular first molar were made and labeled as such: intact molar with no restoration (A); ceramic endocrown-restored molar (B); ceramic crown supported by FRC posts and core restored molar (C). By using 3D FE analysis with contact components, normal masticatory load was simulated. The mvM stresses in all models were calculated. Maximal mvM stresses in the ceramic of restorations, dentin, and luting cement were contrasted among models and to values of materials' strength. Contact shear and tensile stresses in the restoration/tooth interface around restorations were also calculated. The highest mvM stress levels in the enamel and dentin for the tooth restored by ceramic endocrown were lower in the crown ceramic than in tooth restored with FRC posts and all-ceramic crowns; however, in the resin adhesive cement interface it was lower for ceramic crown supported by FRC posts than the in ceramic endocrown restoration. The maximum contact shear and tensile stress values along the restoration/tooth interface of ceramic endocrowns were lower than those with ceramic crowns supported by FRC posts. Ceramic endocrown restorations presented a lower mvM stress level in dentin than the conventional ceramic crowns supported by FRC posts and core. Ceramic endocrown restorations in molars are less susceptible to damage than those with conventional ceramic crowns retained by FRC posts. Ceramic endocrowns properly cemented in molars must not be fractured or loosen during normal masticatory load. Therefore, ceramic endocrowns are advised as practicable, minimally invasive, and esthetic restorations for root canal treated mandibular molars. © 2017 by the American College of Prosthodontists.

Endodontic complications of root canal therapy performed by dental students with stainless-steel K-files and nickel-titanium hand files.

PubMed

Pettiette, M T; Metzger, Z; Phillips, C; Trope, M

1999-04-01

Straightening of curved canals is one of the most common procedural errors in endodontic instrumentation. This problem is commonly encountered when dental students perform molar endodontics. The purpose of this study was to compare the effect of the type of instrument used by these students on the extent of straightening and on the incidence of other endodontic procedural errors. Nickel-titanium 0.02 taper hand files were compared with traditional stainless-steel 0.02 taper K-files. Sixty molar teeth comprised of maxillary and mandibular first and second molars were treated by senior dental students. Instrumentation was with either nickel-titanium hand files or stainless-steel K-files. Preoperative and postoperative radiographs of each tooth were taken using an XCP precision instrument with a customized bite block to ensure accurate reproduction of radiographic angulation. The radiographs were scanned and the images stored as TIFF files. By superimposing tracings from the preoperative over the postoperative radiographs, the degree of deviation of the apical third of the root canal filling from the original canal was measured. The presence of other errors, such as strip perforation and instrument breakage, was established by examining the radiographs. In curved canals instrumented by stainless-steel K-files, the average deviation of the apical third of the canals was 14.44 degrees (+/- 10.33 degrees). The deviation was significantly reduced when nickel-titanium hand files were used to an average of 4.39 degrees (+/- 4.53 degrees). The incidence of other procedural errors was also significantly reduced by the use of nickel-titanium hand files.

Age estimation using the radiographic visibility of the periodontal ligament in lower third molars in a Portuguese population.

PubMed

Sequeira, Catarina-Dourado; Teixeira, Alexandra; Caldas, Inês-Morais; Afonso, Américo; Pérez-Mongiovi, Daniel

2014-12-01

The mineralization of third molars has been used repeatedly as a method of forensic age estimation. However, this procedure is of little use beyond age 18, especially to determinate if an individual is older than 21 years of age; thus, the development of new approaches is essential. The visibility of the periodontal ligament has been suggested for this purpose. The aim of this work was to determine the usefulness of this methodology in a Portuguese population. Periodontal ligament visibility was assessed in the lower third molars, using a sample of 487 orthopantomograms, 228 of which belonging to females and 259 to males, from a Portuguese population aged 17 to 31 years. A classification of four stages based on the visual phenomenon of disappearance of the periodontal ligament of fully mineralized third molars was used. For each stage, median, variance, minimal and maximal age were assessed. The relationship between age and stage of periodontal ligament had a statistical significance for both sexes. In this population, stage 3 can be used to state that a male person is over 21 years-old; for females, another marker should be used. This technique can be useful for determining age over 21, particularly in males. Differences between studies are evident, suggesting that specific population standards should be used when applying this technique. Key words:Forensic sciences, forensic odontology, age estimation, third molar, periodontal ligament.

Eleutherococcus senticosus (Araliaceae) Leaf Morpho-Anatomy, Essential Oil Composition, and Its Biological Activity Against Aedes aegypti (Diptera: Culicidae).

PubMed

Zhai, Chunmei; Wang, Mei; Raman, Vijayasankar; Rehman, Junaid U; Meng, Yonghai; Zhao, Jianping; Avula, Bharathi; Wang, Yan-Hong; Khan, Zhenkun; Khan, Ikhlas A

2017-05-01

The roots of Eleutherococcus senticosus (Rupr. & Maxim.) Maxim., a well-known medicinal plant from Eastern Asia, are used worldwide for their known beneficial medicinal properties. Recently, the leaves have been used as an alternative to the roots. The present study was aimed at exploring the leaf essential oil as a potential source of compounds for mosquito management. Gas chromatography/mass spectrometry analysis of the leaf essential oil revealed 87 compounds, constituting 95.2% of the oil. α-Bisabolol (26.46%), β-caryophyllene (7.45%), germacrene D (6.87%), β-bisabolene (4.95%), and α-humulene (3.50%) were five of the major constituents. The essential oil was subjected to biting deterrence and repellent activity against mosquito Aedes aegypti. The biting deterrence of the oil produced a proportion not biting (PNB) value of 0.62 at 10 µg/cm2 as compared with 0.86 of control DEET (N,N-diethyl-3-methylbenzamide) at a standard dose of 25 nmol/cm2. Among individually selected compounds present in the oil (α-bisabolol, β-caryophyllene, α-humulene, and caryophyllene oxide), only α-bisabolol produced a PNB value of 0.80, equivalent to DEET at 25 nmol/cm2, whereas the others were not repellent. The artificial mixture (AMES-1) of these four selected compounds produced a relatively high PNB value of 0.80. The repellent activity measured by minimum effective dosage (MED) for α-bisabolol and α-humulene produced MED values of 0.094 and 0.104 mg/cm2, respectively, as compared with 0.023 mg/cm2 of DEET. The leaf essential oil, the artificial mixture (AMES-1), and other binary and tertiary combinations of major compounds showed no repellent activity. In addition, morpho-anatomical features of the leaf are provided for correct identification of the species. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Inferring biological evolution from fracture patterns in teeth.

PubMed

Lawn, Brian R; Bush, Mark B; Barani, Amir; Constantino, Paul J; Wroe, Stephen

2013-12-07

It is hypothesised that specific tooth forms are adapted to resist fracture, in order to accommodate the high bite forces needed to secure, break down and consume food. Three distinct modes of tooth fracture are identified: longitudinal fracture, where cracks run vertically between the occlusal contact and the crown margin (or vice versa) within the enamel side wall; chipping fracture, where cracks run from near the edge of the occlusal surface to form a spall in the enamel at the side wall; and transverse fracture, where a crack runs horizontally through the entire section of the tooth to break off a fragment and expose the inner pulp. Explicit equations are presented expressing critical bite force for each fracture mode in terms of characteristic tooth dimensions. Distinctive transitions between modes occur depending on tooth form and size, and loading location and direction. Attention is focussed on the relatively flat, low-crowned molars of omnivorous mammals, including humans and other hominins and the elongate canines of living carnivores. At the same time, allusion to other tooth forms - the canines of the extinct sabre-tooth (Smilodon fatalis), the conical dentition of reptiles, and the columnar teeth of herbivores - is made to highlight the generality of the methodology. How these considerations impact on dietary behaviour in fossil and living taxa is discussed. © 2013 Elsevier Ltd. All rights reserved.

Evaluation of the muscle relaxant cyclobenzaprine after third-molar extraction.

PubMed

de Santana Santos, Thiago; Calazans, Anna Carla Maranhão; Martins-Filho, Paulo Ricardo Saquete; Silva, Luiz Carlos Ferreira da; de Oliveira E Silva, Emanuel Dias; Gomes, Ana Claudia Amorim

2011-10-01

Pain, swelling and trismus are undesirable effects of extraction of impacted mandibular third molars. The authors conducted a study to evaluate the effectiveness of the muscle relaxant cyclobenzaprine when used as a supplement to cryotherapeutic, antibiotic and steroidal anti-inflammatory treatment with the aim of reducing undesirable consequences after third-molar extraction. The authors conducted a prospective, randomized, double-masked, placebo-controlled clinical trial involving 50 participants aged 18 to 29 years randomly assigned to receive cyclobenzaprine or the placebo. The authors used a split-mouth design, so each participant acted as his or her own control. For each participant, the authors extracted one impacted mandibular third molar on each side of the mouth at different times. Participants received 10 milligrams of cyclobenzaprine or a placebo once per day the day before surgery, the day of surgery and the first day after surgery. The authors assessed the participants' postoperative pain by means of a visual analog scale at four, six, eight, 12, 24 and 48 hours. They measured the participants' swelling and maximal interincisor distance at 48 hours and seven days. The authors assessed both sides of each participant's mouth for differences in pain, swelling and trismus. They found no statistically significant differences between sides of the mouth regarding these three variables. The results of this trial indicate that the influence of cyclobenzaprine over pain, swelling and trismus does not justify prescribing additional medication for patients undergoing third-molar extraction. The muscle relaxant cyclobenzaprine was ineffective in reducing pain, swelling and trismus after third-molar extraction.

Pressure production in oral vestibule during gum chewing.

PubMed

Nishiura, M; Ono, T; Yoshinaka, M; Fujiwara, S; Yoshinaka, M; Maeda, Y

2015-12-01

The aim of this study was to record oral vestibule pressure (OVP) by the lip and cheek contraction during gum chewing, to examine the characteristics of these pressures and coordination between the OVP and jaw movement. The subjects were eight healthy adult men (mean age of 29·3 ± 3·3 years). An experimental plate that incorporated four pressure sensors on the midline of the upper jaw (Ch. 1), upper right canine (Ch. 2), upper right first molar (Ch. 3) and upper left first molar (Ch. 4) was used for measuring OVP. The right masseter electromyogram (EMG) was recorded simultaneously. Subjects chewed gum on the right side 20 times, and eight consecutive strokes were used for the analysis of the sequential order, maximal magnitude and duration of each OVP. Onset of OVP was observed at the molar on the non-chewing side (Ch. 4) before chewing side (Ch. 3), and offset was largely simultaneous at each site. On the chewing side (Chs. 1-3), OVP onset during the interval of EMG activity reached to the peak around the end of interval and offset in the duration of EMG activity. The maximal pressure was significantly larger at Chs. 1-3 than at Ch. 4, but no significant differences were observed in duration of pressure among each site. These results suggest that OVP is coordinated with jaw movement during gum chewing, and larger pressure is produced on the chewing side than on the non-chewing side. Our findings are quantitative indices for the evaluation of lip and cheek function during mastication. © 2015 John Wiley & Sons Ltd.

In vivo measurements of maximal occlusal force and minimal pressure threshold on overdentures supported by implants or natural roots: a comparative study, Part 1.

PubMed

Mericske-Stern, R; Hofmann, J; Wedig, A; Geering, A H

1993-01-01

Numerous investigations give evidence of improvement of masticatory performance when edentulous patients have had implants placed. A comparative study was carried out to investigate the oral function and tactile sensibility of patients restored with implant-supported overdentures. Twenty-six patients with ITI implants and 18 patients with natural-tooth roots were selected. The minimal pressure threshold perceived in vertical and horizontal directions was registered with dynamometers. Maximal occlusal force was recorded with a miniature bite recorder placed between each pair of antagonistic teeth on both jaw sides separately. All measurements were repeated three times and the average was calculated. The records of minimal perceived pressure revealed a significantly higher threshold (factor 100) for the implant group. In both test groups, values registered in the vertical direction were slightly increased. A tendency for test subjects with implants to reach higher maximal occlusal force was observed, but not at a statistically significant level. In both test groups, the average maximum was found on the second premolar. The minimal pressure threshold seems to depend on the presence of receptors in the periodontal ligament. The records of maximal occlusal force, which were similar in both test groups, lead to the assumption that the limitation in maximal occlusal capacity of overdenture wearers is multifactorial and does not depend on the presence of a periodontal ligament.

On crack growth in molar teeth from contact on the inclined occlusal surface.

PubMed

Chai, Herzl

2015-04-01

Extracted human molar teeth are indented by hard balls laid at the central fossa, sectioned, and their interior examined for damage. Contact on the fissured enamel coat generally occurs on three distinct spots. The main forms of damage are radial cracks growing from the DEJ to the occlusal surface and median radial and cylindrical cracks growing from a contact spot to the DEJ. For large balls failure by edge chipping near a cusp apex may occur. The median cracks tend to run unstably to the DEJ upon reaching the middle part of the enamel coat. The corresponding load, PFM, and the load needed to initiate radial cracks at the DEJ, PFR, are taken to signal crown failure. The mean values of PFM and PFR are on the order of 1000N. A conical bilayer model defined by thickness d, inclination angle θ, failure stress σF and toughness KC of the enamel coat is developed to assess crown failure. The analytical predictions for PFR and PFM agree well with the tests. The results indicate that enamel thickness is so designed as to ensure that PFR and PFM just exceed the maximum bite force under normal conditions while the choice of θ seems to reflect a compromise between needs to resist crown failure and break hard food particles. Both PFR and PFM are greatly reduced with reducing d, which points to the danger posed by tooth wear. The analytical expressions for PFR and PFM may also apply to other multi-cusp mammalian or prosthetic molar crowns. Cone cracking, suppressed in the anisotropic tooth enamel, may be an important failure mode in prosthetic crowns. Copyright © 2014 Elsevier Ltd. All rights reserved.

Occlusal traits and orthodontic treatment need in 7‐ to 10‐year‐olds in Estonia

PubMed Central

Saag, Mare; Svedström‐Oristo, Anna‐Liisa; Peltomäki, Timo; Vinkka‐Puhakka, Heli

2017-01-01

Abstract The aim of this study was to evaluate the distribution of occlusal traits and orthodontic treatment need and complexity in Estonian 7‐ to 10‐year‐old children. This data provides solid information for planning of orthodontic care. Data of 392 Estonian children (198 girls and 194 boys, mean age 9.0 years, range 7.1–10.4 years) was analysed in this cross‐sectional study. Assessed traits included first molar and canine sagittal relationship, overjet, overbite, crowding, midline diastema, crossbite, and scissor bite. Orthodontic treatment need and complexity were assessed using the Index of Complexity, Outcome, and Need. Parents' opinion regarding their child's teeth was determined using a questionnaire. The most prevalent occlusal traits were canine class I sagittal relationship (73.7%), midline diastema (73.0%), molar class I sagittal relationship (57.4%), and overbite ≥3.5 mm (51.8%). According to the Index of Complexity, Outcome, and Need, 64.3% of Estonian elementary school children were in need of orthodontic treatment. Treatment complexity was simple in 12.5%, mild in 38.8%, moderate in 22.7%, difficult in 14.0%, and very difficult in 12.0% of the children. Approximately 66.4% of the parents felt that their child needed orthodontic treatment. This study confirms earlier findings indicating that the most frequent sagittal relationship is class I in the first molars and class I in the canines. However, the sagittal relationship was asymmetric in more than half of the children. Correlation between objectively defined treatment need and parents' desire for treatment was high in Estonia. PMID:29744185

Remarkable resilience of teeth.

PubMed

Chai, Herzl; Lee, James J-W; Constantino, Paul J; Lucas, Peter W; Lawn, Brian R

2009-05-05

Tooth enamel is inherently weak, with fracture toughness comparable with glass, yet it is remarkably resilient, surviving millions of functional contacts over a lifetime. We propose a microstructural mechanism of damage resistance, based on observations from ex situ loading of human and sea otter molars (teeth with strikingly similar structural features). Section views of the enamel implicate tufts, hypomineralized crack-like defects at the enamel-dentin junction, as primary fracture sources. We report a stabilization in the evolution of these defects, by "stress shielding" from neighbors, by inhibition of ensuing crack extension from prism interweaving (decussation), and by self-healing. These factors, coupled with the capacity of the tooth configuration to limit the generation of tensile stresses in largely compressive biting, explain how teeth may absorb considerable damage over time without catastrophic failure, an outcome with strong implications concerning the adaptation of animal species to diet.

Occlusal plane rotation: aesthetic enhancement in mandibular micrognathia.

PubMed

Rosen, H M

1993-06-01

Patients afflicted with extreme degrees of mandibular micrognathia typically have vertically deficient rami as well as sagittally deficient mandibular bodies. This results in deficient posterior facial height, an obtuse gonial angle, excessively steep occlusal and mandibular planes, and a compensatory increase in anterior facial height. The entire maxillomandibular complex is overrotated in a clockwise direction. Standard orthognathic surgical correction fails to address this rotational deformity. As a consequence, the achieved projection of the lower face is inadequate, posterior facial height is further reduced, and occlusal and mandibular planes remain steep. Eleven patients with severe mandibular micrognathia underwent a surgical correction involving occlusal plane rotation to its normal orientation relative to Frankfort horizontal. This was accomplished by Le Fort I osteotomy to shorten the anterior maxilla (creating open bites in seven patients and making preexisting open bites worse in four patients) and sagittal split ramus osteotomies to advance and rotate the mandibular body counterclockwise, thus closing the surgically produced open bite. Counterclockwise rotation of the mandible afforded significantly greater sagittal displacement at the B point (mean 17 mm) than at the first molar (mean 10 mm) and produced adequate degrees of projection of the lower face when accompanied by a modest sliding genioplasty (mean 6.9 mm). Total advancement at the pogonion was a mean of 25.2 mm. In addition, posterior facial height was preserved, and mandibular and occlusal planes were normalized to mean angles of 27 and 10 degrees, respectively. At follow-up, which ranged from 9 to 24 months with a mean of 14.1 months, the mean sagittal relapse at the B point was 1.9 mm. Although heretofore considered unstable and therefore not clinically accepted, maxillomandibular counterclockwise rotation to normalize the occlusal plane rotational deformity provides stable, aesthetically superior results in patients with extreme degrees of mandibular micrognathia. Extended follow-up will be necessary to document long-term stability.

Effects of breast-feeding duration, bottle-feeding duration and non-nutritive sucking habits on the occlusal characteristics of primary dentition.

PubMed

Chen, Xiaoxian; Xia, Bin; Ge, Lihong

2015-04-21

Early transition from breastfeeding and non-nutritive sucking habits may be related to occlusofacial abnormalities as environmental factors. Previous studies have not taken into account the potential for interactions between feeding practice, non-nutritive sucking habits and occlusal traits. This study assessed the effects of breast-feeding duration, bottle-feeding duration and non-nutritive sucking habits on the occlusal characteristics of primary dentition in 3-6-year-old children in Peking city. This cross sectional study was conducted via an examination of the occlusal characteristics of 734 children combined with a questionnaire completed by their parents/guardians. The examination was performed by a single, previously calibrated examiner and the following variables were evaluated: presence or absence of deep overbite, open bite, anterior crossbite, posterior crossbite, deep overjet, terminal plane relationship of the second primary molar, primary canine relationship, crowding and spacing. Univariate analysis and multiple logistic regressions were applied to analyze the associations. It was found that a short duration of breast-feeding (never or ≤ 6 months) was directly associated with posterior cross bite (OR = 3.13; 95% CI = 1.11-8.82; P = 0.031) and no maxillary space (OR = 1.63; 95% CI = 1.23-2.98; P = 0.038). In children breast-fed for ≤ 6 months, the probability of developing pacifier-sucking habits was 4 times that for those breast-fed for >6 months (OR = 4.21; 95% CI = 1.85-9.60; P = 0.0002). Children who were bottle-fed for over 18 months had a 1.45-fold higher risk of nonmesial step occlusion and a 1.43-fold higher risk of a class II canine relationship compared with those who were bottle-fed for up to 18 months. Non-nutritive sucking habits were also found to affect occlusion: A prolonged digit-sucking habit increased the probability of an anterior open bite, while a pacifier-sucking habit associated with excessive overjet and absence of lower arch developmental space. Breastfeeding duration was shown to be associated with the prevalence of posterior crossbite, no maxillary space in the deciduous dentition and development of a pacifier-sucking habit. Children who had a digit-sucking habit were more likely to develop an open bite.

[Expression of homeobox gene Msx-1, Msx-2 and Dlx-2 during murine mandibular first molar development].

PubMed

Ma, Li; Chen, Zhi; Song, Guang-tai; Fan, Ming-wen; Zhang, Qi; Wang, Zhi-feng

2003-11-01

To observe the expression of homeobox gene Msx-1, Msx-2 and Dlx-2 during murine mandibular first molar development. The murine heads or mandibles on embryonic days 11-18 (E11-18) and postnatal day 1-3 (P1-3) were removed, fixed and embedded, 5 micro m serial sections were cut in the coronal plane. Msx-1, Msx-2 and Dlx-2 RNA probes were synthesized by in vitro transcription and labeled with digoxigenin. Msx-1, Msx-2 and Dlx-2 mRNA expression was observed after in situ hybridization. During molar development Msx-1 transcripts appeared only in mesenchymal cells, not in epithelial cells. Msx-2 and Dlx-2 both expressed in the epithelial and mesenchymal cells. At the initiation stage of the molar development Msx-2 and Dlx-2 had similar expression. At the bud stage (E13-14) Msx-2 mRNA signaling was intensive in the enamel organ and slight in the dental mesenchyme; Dlx-2 signaling was stronger in the dental papilla. At cap stage (E15-16) Msx-2 showed prominent mRNA signaling in enamel knot and Dlx-2 was maximal in the dental papilla. At the late bell stage (P2-3) Msx-2 transcripts were observed in odontoblasts but not labeled in ameloblasts, and Dlx-2 transcripts appeared in ameloblasts but no labeling was seen in odontoblasts. Msx-1, Msx-2 and Dlx-2 are expressed in various patterns during murine mandibular first molar development, suggesting they possibly play a role in the interaction between the epithelium and mesenchyme during the molar development.

Clinical and Radiographic Characteristics as Predictive Factors of Swelling and Trismus after Mandibular Third Molar Surgery: A Longitudinal Approach

PubMed Central

Pérez-González, José Manuel; Esparza-Villalpando, Vicente; Martínez-Rider, Ricardo; Noyola-Frías, Miguel Ángel

2018-01-01

Introduction Factors that contribute to swelling and trismus are complex, and they are originated by surgical trauma. The aim of the present study was to determine whether clinical and radiographic factors could predict the level of swelling and trismus after lower third molar surgery, through longitudinal approach. Methodology A prospective longitudinal trial was carried out. Forty-five patients of both genders with clinical and radiographic diagnosis of asymptomatic mandibular impacted third molar and with no intake of analgesic or anti-inflammatory drugs 12 h prior to surgery were recruited and evaluated in a 72 h follow-up period. A mixed repeated measures model and backward and restricted maximal likelihood methods were used to analyze the data. Results Male gender, body mass index (BMI), the relation to the lingual and buccal walls, and age were determinants for predicting postoperative swelling and for exerting a significant influence (P < 0.05). Conclusions This study suggests the association of male gender, the relation to lingual and buccal walls, BMI, and age with measurement of swelling. PMID:29849848

Articaine and mepivacaine buccal infiltration in securing mandibular first molar pulp anesthesia following mepivacaine inferior alveolar nerve block: A randomized, double-blind crossover study

PubMed Central

Gazal, Giath; Alharbi, Abdullah Muteb; Al-Samadani, Khalid HidayatAllah; Kanaa, Mohammad Dib

2015-01-01

Aims: A crossover double-blind, randomized study was designed to explore the efficacy of 2% mepivacaine with 1:100,000 adrenaline buccal infiltration and 4% articaine with 1:100,000 adrenaline buccal infiltration following 2% mepivacaine with 1:100,000 adrenaline inferior alveolar nerve block (IANB) for testing pulp anesthesia of mandibular first molar teeth in adult volunteers. Materials and Methods: A total of 23 healthy adult volunteers received two regimens with at least 1-week apart; one with 4% articaine buccal infiltration and 2% mepivacaine IANB (articaine regimen) and another with 2% mepivacaine buccal infiltration supplemented to 2% mepivacaine IANB (mepivacaine regimen). Pulp testing of first molar tooth was electronically measured twice at baseline, then at intervals of 2 min for the first 10 min, then every 5 min until 45 min postinjection. Anesthetic success was considered when two consecutive maximal stimulation on pulp testing readings without sensation were obtained within 10 min and continuously sustained for 45 min postinjection. Results: In total, the number of no sensations to maximum pulp testing for first molar teeth were significantly higher after articaine regimen than mepivacaine during 45 min postinjection (267 vs. 250 episodes, respectively, P < 0.001), however, both articaine and mepivacaine buccal infiltrations are equally effective in securing anesthetic success for first molar pulp anesthesia when supplemented to mepivacaine IANB injections (P > 0.05). Interestingly, volunteers in the articaine regimen provided faster onset and longer duration (means 2.78 min, 42.22 min, respectively) than mepivacaine regimen (means 4.26 min, 40.74 min, respectively) for first molar pulp anesthesia (P < 0.001). Conclusions: Supplementary mepivacaine and articaine buccal infiltrations produced similar successful first molar pulp anesthesia following mepivacaine IANB injections in volunteers. Articaine buccal infiltration produced faster onset and longer duration than mepivacaine buccal infiltration following mepivacaine IANB injections. PMID:26543456

Articaine and mepivacaine buccal infiltration in securing mandibular first molar pulp anesthesia following mepivacaine inferior alveolar nerve block: A randomized, double-blind crossover study.

PubMed

Gazal, Giath; Alharbi, Abdullah Muteb; Al-Samadani, Khalid HidayatAllah; Kanaa, Mohammad Dib

2015-01-01

A crossover double-blind, randomized study was designed to explore the efficacy of 2% mepivacaine with 1:100,000 adrenaline buccal infiltration and 4% articaine with 1:100,000 adrenaline buccal infiltration following 2% mepivacaine with 1:100,000 adrenaline inferior alveolar nerve block (IANB) for testing pulp anesthesia of mandibular first molar teeth in adult volunteers. A total of 23 healthy adult volunteers received two regimens with at least 1-week apart; one with 4% articaine buccal infiltration and 2% mepivacaine IANB (articaine regimen) and another with 2% mepivacaine buccal infiltration supplemented to 2% mepivacaine IANB (mepivacaine regimen). Pulp testing of first molar tooth was electronically measured twice at baseline, then at intervals of 2 min for the first 10 min, then every 5 min until 45 min postinjection. Anesthetic success was considered when two consecutive maximal stimulation on pulp testing readings without sensation were obtained within 10 min and continuously sustained for 45 min postinjection. In total, the number of no sensations to maximum pulp testing for first molar teeth were significantly higher after articaine regimen than mepivacaine during 45 min postinjection (267 vs. 250 episodes, respectively, P < 0.001), however, both articaine and mepivacaine buccal infiltrations are equally effective in securing anesthetic success for first molar pulp anesthesia when supplemented to mepivacaine IANB injections (P > 0.05). Interestingly, volunteers in the articaine regimen provided faster onset and longer duration (means 2.78 min, 42.22 min, respectively) than mepivacaine regimen (means 4.26 min, 40.74 min, respectively) for first molar pulp anesthesia (P < 0.001). Supplementary mepivacaine and articaine buccal infiltrations produced similar successful first molar pulp anesthesia following mepivacaine IANB injections in volunteers. Articaine buccal infiltration produced faster onset and longer duration than mepivacaine buccal infiltration following mepivacaine IANB injections.

Miniplate With a Bendable C-Tube Head Allows the Clinician to Alter Biomechanical Advantage in Extremely Complicated Anatomic Structure.

PubMed

Seo, Kyung Won; Iskenderoglu, Nur Serife; Hwang, Eui Hwan; Chung, Kyu-Rhim; Kim, Seong-Hun

2017-05-01

This article reports C-tube miniplates as a practical temporary anchorage device choice to treat open bite patients with maxillary sinus pneumatization. The C-tube components are titanium anchor plates and monocortical screws that are basically similar to any other miniplate systems, but it has the unique characteristic of the tube head to be malleable. The manipulation of the head part is easy due to the composition of pure titanium. The I-shaped C-tube with 3 holes and T-shaped C-tube miniplates were placed above the apices of maxillary molars as an absolute anchorage system to intrude the posterior maxilla. The bending of the tube heads assisted in reduction of severe open bite patient with maxillary sinus pneumatization. Sinus perforation during placement of skeletal anchorage system weakens stability of the anchorage and further cause complications. Placement of titanium C-tube miniplates allowed reliable skeletal anchorage and avoided maxillary sinus perforation in patients with extreme pneumatizations. Simple bending of C-tube miniplates ensured increased orthodontic intrusion force without having to replace them, and eliminated consequences such as perforation of maxillary sinus, sinusitis, soft tissue irritation, or infection. Anatomic difficulties in the placement of temporary anchorage device can be easily managed by using the bendable C-tube miniplate. It can serve as a great alternative over miniscrews or regular miniplates with reduced risk of sinus perforation and ability to bend the head portion to control orthodontic vectors and forces.

On the Relationship Between Tooth Shape and Masticatory Efficiency: A Finite Element Study.

PubMed

Berthaume, Michael A

2016-05-01

Dental topography has successfully linked disparate tooth shapes to distinct dietary categories, but not to masticatory efficiency. Here, the relationship between four dental topographic metrics and brittle food item breakdown efficiency during compressive biting was investigated using a parametric finite element model of a bunodont molar. Food item breakdown efficiency was chosen to represent masticatory efficiency as it isolated tooth-food item interactions, where most other categories of masticatory efficiency include several aspects of the masticatory process. As relative food item size may affect the presence/absence of any relationship, four isometrically scaled, hemispherical, proxy food items were considered. Topographic metrics were uncorrelated to food item breakdown efficiency irrespective of relative food item size, and dental topographic metrics were largely uncorrelated to one another. The lack of a correlation between topographic metrics and food item breakdown efficiency is not unexpected as not all food items break down in the same manner (e.g., nuts are crushed, leaves are sheared), and only one food item shape was considered. In addition, food item breakdown efficiency describes tooth-food item interactions and requires location and shape specific information, which are absent from dental topographic metrics. This makes it unlikely any one efficiency metric will be correlated to all topographic metrics. These results emphasize the need to take into account how food items break down during biting, ingestion, and mastication when investigating the mechanical relationship between food item shape, size, mechanical properties, and breakdown, and tooth shape. © 2016 Wiley Periodicals, Inc.

Malocclusion and dental caries experience among 8–9-year-old children in a city of South Indian region: A cross-sectional survey

PubMed Central

Disha, Patil; Poornima, P.; Pai, Suryakanth M.; Nagaveni, N. B.; Roshan, N. M.; Manoharan, M.

2017-01-01

BACKGROUND: Although numerous studies have documented malocclusion in various age groups in India, the literature on the prevalence of malocclusion in mixed dentition is scanty. Dental caries is another most common condition affecting the general health. However, its association with malocclusion in mixed dentition is not well known. AIM: The purpose of this study was to establish the prevalence of malocclusion and its association with caries experience in 8–9-year-old children of Davangere city, South Indian region. SETTING AND DESIGN: The study design was a cross-sectional survey. MATERIALS AND METHODS: A total of 800 children from 350 schools (both males and females) were randomly selected for the study. t-test and Chi-square test were used for statistical analysis. RESULTS: The overall prevalence of malocclusion among 8–9-year-old children was 40.9%. The most prevalent malocclusion was crowding (11.5%), followed by excessive overjet (9.4%), deep bite (6.8%), spacing (6.5%), crossbite (4.5%), and open bite (3.2%). Class I molar relationship prevailed in 95.5% of children. CONCLUSION: The prevalence of malocclusion in our study was in accordance with the other studies reported in India, which ranged from 19.6% to 90%. Furthermore, correlation of malocclusion and dental caries in the primary dentition, although nonsignificant, presented children with malocclusion to have a higher caries experience than children without malocclusion. PMID:29296599

[Z2 appliance: the pre-adjusted appliance based on Chinese normal occlusion].

PubMed

Zeng, Xiang-long; Gao, Xue-mei

2008-12-01

Z2 appliance is the pre-adjusted appliance designed for Chinese orthodontic patients. The prescription of the appliance is based on Chinese normal occlusion, which is much different from the West in the first and the second orders as well as the third one. The appliance routinely includes 20 brackets and 8 molar buccal tubers with 3 standard arch forms. Clinically, continued light force is used in whole treatment. The side-effects such as forward tipping of incisors, bite deepening and loss of molar anchorage are reduced further due to fewer tips built into the anterior brackets as well as lower friction elastometric modules used during aligning and leveling. In condition of arch are leveled completely, 0.48 mm x 0.64 mm stainless steel archwire with 1.47 N retraction force is the best combination for sliding mechanics, which is proved by 3D nonlinear finite element study. Self drilling micro-screw is used for maximum anchorage. In finishing stage 0.53 mm x 0.64 mm NT arch wire is added in order to get full torque expressing. The research of Chinese pre-adjusted appliance has been lasted for more than 10 years in the department and clinical studies on Z2 appliance show that with minimal wire bending, treatment is more efficient and result is high quality and more consistent for Chinese orthodontic patients.

Dynamic Nanocomposite Self-Deactivating Fabrics for the Individual and Collective Protection

DTIC Science & Technology

2006-11-01

poly-ß-cyclodextrins (PCDs) and poly- trehalose (PTH) as polymeric supports, the incorporated enzymes will be able to repair themselves through a re...POLY- TREHALOSE (PTH) In a similar manner, polymeric trehalose (PTH) was also prepared in a different molar ratio optimized to maximize...MPT), polymeric trehalose (PTH) particles were prepared as a complementary substrate to poly-ß- CD particles in various aspects serving as an

Estimation of Dog-Bite Risk and Related Morbidity Among Personnel Working With Military Dogs.

PubMed

Schermann, H; Eiges, N; Sabag, A; Kazum, E; Albagli, A; Salai, M; Shlaifer, A

Soldiers serving in the Israel Defense Force Military Working Dogs (MWD) Unit spend many hours taming dogs' special skills, taking them on combat missions, and performing various dogkeeping activities. During this intensive work with the aggressive military dogs, bites are common, and some of them result in permanent disability. However, this phenomenon has not been quantified or reported as an occupational hazard. This was a retrospective cohort study based on self-administered questionnaires. Information was collected about soldiers' baseline demographics, duration of the experience of working with dogs, total number of bites they had, circumstances of bite events, and complications and medical treatment of each bite. Bite risk was quantified by incidence, mean time to first bite, and a Cox proportional hazards model. Rates of complications and the medical burden of bites were compared between combat soldiers and noncombat dogkeepers. Bite locations were presented graphically. Seventy-eight soldiers participated and reported on 139 bites. Mean time of working with dogs was 16 months (standard deviation, ±9.4 months). Overall bite incidence was 11 bites per 100 person-months; the mean time to first bite event was 6.3 months. The Cox proportional hazards model showed that none of baseline characteristics significantly increased bite hazard. About 90% of bites occurred during routine activities, and 3.3% occurred on combat missions. Only in 9% of bite events did soldiers observed the safety precautions code. Bite complications included fractures, need for intravenous antibiotic treatment and surgical repair, prominent scarring, diminished sensation, and stiffness of proximal joints. Bite complications were similar between combat soldiers and dogkeepers. Most bites (57%) were located on hands and arms. MWD bites are an occupational hazard resulting in significant medical burden. Hands and arms were most common bite locations. Observance of safety precautions may be the most appropriate first-line preventive intervention. Barrier protection of upper extremities may reduce bite severity and complication rates. 2017.

Tooth eruption in a patient with craniometaphyseal dysplasia: case report.

PubMed

Hayashibara, T; Komura, T; Sobue, S; Ooshima, T

2000-10-01

Craniometaphyseal dysplasia (CMD) is a very rare genetic disorder of bone remodeling caused by osteoclast dysfunction. The clinical and radiographical features of oral findings are presented in a sporadic case of CMD in a child (age 10 years, 7 months). An intraoral examination showed severe malocclusions, including anterior crossbite and deep bite. Furthermore, a radiographic examination showed increased radiopacity of the maxilla and mandibular bones due to hyperostosis and sclerosis of the jaw. There was no root resorption of the canines or molars in the primary dentition, although root formation of the permanent teeth was proceeding. Dental age was calculated to be approximately 1 year, 4 months younger than his chronological age. The eruption speed of the permanent lateral incisors after the gingival emergence was shown to be within normal values, and we discuss whether the canines and premolars in the permanent dentition could erupt or not.

Multidisciplinary treatment approach in Treacher Collins syndrome.

PubMed

Hylton, Joseph B; Leon-Salazar, Vladimir; Anderson, Gary C; De Felippe, Nanci L O

2012-01-01

Treacher Collins syndrome (TCS) is a common genetic disorder with high penetrance and phenotypic variability. First and second branchial arches are affected in TCS, resulting in craniofacial and intraoral anomalies such as: severe convex facial profile; mid-face hypoplasia; microtia; eyelid colobomas; mandibular retrognathism; cleft palate; dental hypoplasia; heterotopic teeth; maxillary transverse hypoplasia; anterior open bite; and Angle Class II molar relationship. A high incidence of caries is also a typical finding in TCS patients. Nonetheless, even simple dental restorative procedures can be challenging in this patient population due to other associated medical conditions, such as: congenital heart defects; decreased oropharyngeal airways; hearing loss; and anxiety toward treatment. These patients often require a multidisciplinary treatment approach, including: audiology; speech and language pathology; otorhinolaryngology; general dentistry; orthodontics; oral and maxillofacial surgery; and plastic and reconstructive surgeries to improve facial appearance. This paper's purpose was to present a current understanding of Treacher Collins syndrome etiology, phenotype, and current treatment approaches.

Animal bites - self-care

MedlinePlus

Bites - animals - self-care ... Most animal bites come from pets. Dog bites are common and most often happen to children. Cat bites are ... which can cause deeper puncture wounds. Most other animal bites are caused by stray or wild animals, ...

A fatal mongoose bite.

PubMed

Tumram, Nilesh Keshav; Bardale, Rajesh Vaijnathrao; Dixit, Pradeep Gangadhar; Deshmukh, Ashutosh Yashwant

2012-11-19

Animal bite is a bite wound from a pet, farm or wild animal. Dog bites make up 80-85% of all reported incidents. Cats amount for about 10% of reported bites and other animals such as rodents, rabbits, horses, raccoons, bats and monkeys amount to 5-10%. Bites by mongoose are uncommon. Here, we present a case of fatal mongoose bite to an elderly woman who died as a complication of streptococcal infection at the bite site.

Epidemiologic and clinical aspects of animal bite injuries.

PubMed

Kizer, K W

1979-04-01

During 1975, 332 animal bite injuries accounted for 1.2% of all surgical problems treated at the UCLA Hospital Emergency Department. Data on 307 bite injuries were available and analyzed for environmental, animal, human, interaction, and clinical factors. More than half of the dog bites and almost three fourths of the cat bites-scratches happened at or near the victims' homes. Dog bites were almost twice as common among men, while cat bites-scratches were twice as common among women. Of the incidents in which ownership information was available, 85% of dog bites and 80% of cat bites-scratches were from an animal belonging to the victim, his family or friends, or another known person. Forty-three percent of dog bites, and 52% of cat bites-scratches were provoked, that is, happened while the victim was interacting with the animal. Of bites of the head and/or neck, 38% injured the upper lip; 17% of dog bites injured the eye or adjacent tissues; 48% were in children less than ten-years-old. On fifth of cat bites-scratches involved the head and/or neck, 60% of these injured orbital or periorbital tissues. Over 2% of patients were hospitalized. Five percent of dog bite victims and 29% of cat bite-scratch victims returned with complications, mostly cellulitis or lymphangitis. Pasteurella multocida was the most common pathogen cultured, as evidenced by the 50% and 80% culture-positive rates for dog and cat bite-scratches respectively in this series.

Cat and Dog Bites

MedlinePlus

... Wellness Staying Healthy Pets and Animals Cat and Dog Bites Cat and Dog Bites Share Print Cat and dog bites are common injuries. A family pet or ... bites. Path to safety If a cat or dog bites you, you should: Wash the wound gently ...

Floral Induction in a Photoperiodically Insensitive Duckweed, Lemna paucicostata LP6 1

PubMed Central

Khurana, J. P.; Tamot, B. K.; Maheshwari, S. C.

1988-01-01

The effects of 20 amino acids and two amides were studied on the flowering of a photoperiodically insensitive duckweed, Lemna paucicostata LP6. Alanine, asparagine, aspartate, cystine, glutamate, glutamine, glycine, lysine, methionine, proline, serine, and threonine induced flowering under a photoperiodic regime of 16 hours light and 8 hours darkness. Among these, glutamate and aspartate were found to be the most effective for flower induction. These acids could initiate flowering even at 5 × 10−7 molar level, though maximal flowering (about 80%) was obtained at 10−5 molar. Change in the photoperiodic schedule or the pH of the nutrient medium did not influence glutamate- or aspartate-induced flowering. The low concentrations at which glutamate and aspartate are effective suggests that they may have a regulatory role rather than simply acting as metabolites. PMID:16666006

Dog and cat bites: epidemiologic analyses suggest different prevention strategies.

PubMed Central

Patrick, G R; O'Rourke, K M

1998-01-01

OBJECTIVE: To examine the characteristics of reported dog and cat bite incidents in El Paso, Texas, and their implications for local bite prevention programs. METHODS: The authors reviewed a random sample of reported dog bites and all reported cat bites in El Paso, Texas, in 1995 using existing animal control surveillance data. RESULTS: The majority of cat bites (89.4%) were provoked, with females (57.5%) and adults (68.3%) more likely to be victims than males or children. In contrast, just under half of dog bites (44.6%) were provoked, with males (65.6%) and children (63%) more likely to be victims than females or adults. Dogs that had not been vaccinated for rabies were involved in 65% of dog bites and cats that had not been vaccinated for rabies were involved in 92% of cat bites. CONCLUSION: Effective bite prevention programs should address the finding that both restrained and unrestrained dogs may bite even when unprovoked and that unrestrained cats usually bite when provoked. PMID:9633872

Cause, setting and ownership analysis of dog bites in Bay County, Florida from 2009 to 2010.

PubMed

Matthias, J; Templin, M; Jordan, M M; Stanek, D

2015-02-01

Emergency room and hospital discharge data have been used to describe the risk factors and public health impact of dog bites. These data sets are based on financial charges for severe bites and underestimates dog bite burdens within communities. This study expands both the source of information and risk factor data collected to provide demographic analysis of dog bite injury risk factors reported in Bay County, Florida in 2009-2010. Extended data for dog bites reported by various sources from January 1, 2009 to December 31, 2010 were collected by Florida Department of Health in Bay County. Data collected included bite victim's age and gender, primary reported cause of bite, setting, dog's restraint status and relationship between the victim and the dog. A total of 799 bites were reported. Most bites (55%) were reported first by healthcare practitioners, particularly bites involving children<6 years. Bites involving unfamiliar dogs and dogs off the owner's property were more likely to be reported by other sources. Boys aged 6-14 years accounted for 2.24 times more bites than same-aged females (P<0.001) and had the highest incidence with 424 bites per 100,000 persons per year. Persons 6 years or older were 3.6 times more likely to be bitten by an unfamiliar dog. Inappropriate behaviour management was the most common cause of bites (26%), followed by protective behaviour (24%). Bites of unknown cause were 2.5 times more likely in children<6 years. Separating dog fights was the most common cause of bites for persons 15 years or older (24%); females were significantly more likely to be bit than males (P=0.01). Bites by unrestrained dogs off the owner's property (32% of all bites) most commonly involved males. Estimates based solely on healthcare discharge data significantly underestimate dog bite burden within a community. Characterizing these risks by age group or gender provides an opportunity to implement targeted interventions to prevent dog bites. © 2014 Blackwell Verlag GmbH.

Monkey bites among US military members, Afghanistan, 2011.

PubMed

Mease, Luke E; Baker, Katheryn A

2012-10-01

Bites from Macaca mulatta monkeys, native to Afghanistan, can cause serious infections. To determine risk for US military members in Afghanistan, we reviewed records for September-December 2011. Among 126 animal bites and exposures, 10 were monkey bites. Command emphasis is vital for preventing monkey bites; provider training and bite reporting promote postexposure treatment.

Effect of ebastine on mosquito bites.

PubMed

Reunala, T; Brummer-Korvenkontio, H; Petman, L; Palosuo, T; Sarna, S

1997-07-01

Mosquito bites usually cause wealing and delayed bite papules. Cetirizine decreases wealing, bite papules and pruritus but the effect of other antihistamines on mosquito bites is unknown. We studied the effect of ebastine in 30 mosquito bite-sensitive adult subjects. Ebastine 10 mg or 20 mg and placebo were given for 4 days in a cross-over fashion. Aedes aegypti bites were given on forearms. The size of the bite lesions and pruritus (visual analogue score) were measured at 15 min, 2, 6, and 24 h after the bites. Twenty-five subjects were evaluable in the study. At 15 min ebastine decreased significantly the size of the bite lesion (p = 0.0017) and pruritus (p<0.0001). The effects of 10 mg and 20 mg of ebastine were similar. No significant effect was found at 2, 6 or 24 h, but when the measurements at all four time points were compiled the size of the bite lesion and pruritus score decreased significantly. Sedation occurred during ebastine treatment in 6 (21%) and during placebo treatment in 2 (7%) subjects. The present results show that prophylactically given ebastine is effective against immediate mosquito bite symptoms.

Associations of types of pain with crack-level, tooth-level and patient-level characteristics in posterior teeth with visible cracks: Findings from the National Dental Practice-Based Research Network.

PubMed

Hilton, Thomas J; Funkhouser, Ellen; Ferracane, Jack L; Gordan, Valeria V; Huff, Kevin D; Barna, Julie; Mungia, Rahma; Marker, Timothy; Gilbert, Gregg H

2018-03-01

The objective of this study was to determine which patient traits, behaviors, external tooth and/or crack characteristics correlate with the types of symptoms that teeth with visible cracks exhibit, namely pain on biting, pain due to cold stimuli, or spontaneous pain. Dentists in the National Dental Practice-Based Research Network enrolled a convenience sample of subjects each of whom had a single, vital posterior tooth with at least one observable external crack (cracked teeth); 2858 cracked teeth from 209 practitioners were enrolled. Data were collected at the patient-, tooth-, and crack-level. Generalized estimating equations were used to obtain significant (p < .05) independent odds ratios (OR) associated with teeth that were painful for 10 outcomes based on types of pain and combinations thereof. Overall, 45% of cracked teeth had one or more symptoms. Pain to cold was the most common symptom, which occurred in 37% of cracked teeth. Pain on biting (16%) and spontaneous pain (11%) were less common. Sixty-five percent of symptomatic cracked teeth had only one type of symptom, of these 78% were painful only to cold. No patient-, tooth- or crack-level characteristic was significantly associated with pain to cold alone. Positive associations for various combinations of pain symptoms were present with cracks that: (1) were on molars; (2) were in occlusion; (3) had a wear facet through enamel; (4) had caries; (5) were evident on a radiograph; (6) ran in more than one direction; (7) blocked transilluminated light; (8) connected with another crack; (9) extended onto the root; (10) extended in more than one direction; or (11) were on the distal surface. Persons who were <65 yo or who clench, grind, or press their teeth together also were more likely to have pain symptoms. Pain was less likely in teeth with stained cracks or exposed roots, or in non-Hispanic whites. Although pain to cold was the most commonly noted pain associated with symptomatic cracked teeth, no patient-, tooth- or crack-level characteristic was significantly associated with pain to cold alone. Characteristics were only associated with pain on biting and/or spontaneous pain with or without pain to cold. Although often considered the most reliable diagnosis for a cracked tooth, pain on biting is not the most common symptom of a tooth with a visible crack, but rather pain to cold. Copyright © 2017 Elsevier Ltd. All rights reserved.

Factors Associated with Tick Bite Preventive Practices among Farmworkers in Malaysia

PubMed Central

Wong, Li Ping; Tay, Sun Tee; Bulgiba, Awang; Zandi, Keivan; Kho, Kai Ling; Koh, Fui Xian; Ong, Bee Lee; Jaafar, Tariq; Hassan Nizam, Quaza Nizamuddin

2016-01-01

Background Farmworkers are at high-risk for tick bites, which potentially transmit various tick-borne diseases. Previous studies show that personal prevention against tick bites is key, and certain factors namely, knowledge, experience of tick bites, and health beliefs influence compliance with tick bites preventive behaviour. This study aimed to assess these factors and their associations with tick bite preventive practices among Malaysian farmworkers. Methods A total of eight cattle, goat and sheep farms in six states in Peninsular Malaysia participated in a cross-sectional survey between August and October 2013 Results A total of 151 (72.2%) out of 209 farmworkers answered the questionnaire. More than half of the farmworkers (n = 91) reported an experience of tick bites. Farms with monthly acaricide treatment had significantly (P<0.05) a low report of tick bites. Tick bite exposure rates did not differ significantly among field workers and administrative workers. The mean total knowledge score of ticks for the overall farmworkers was 13.6 (SD±3.2) from 20. The mean total tick bite preventive practices score for all farmworkers was 8.3 (SD±3.1) from 15. Fixed effect model showed the effects of four factors on tick bite prevention: (1) farms, (2) job categories (administrative workers vs. field workers), (3) perceived severity of tick bites, and (4) perceived barriers to tick bite prevention. Conclusions A high proportion of farmworkers, including administrative workers, reported an experience of tick bites. The effectiveness of monthly acaricide treatment was declared by low reports of tick bites on these farms. Tick bite preventive practices were insufficient, particularly in certain farms and for administrative workers. Our findings emphasise the need to have education programmes for all farmworkers and targeting farms with low prevention practices. Education and health programmes should increase the perception of the risk of tick bites and remove perceived barriers of tick bite prevention. PMID:27341678

Human Bites in the Classroom: Incidence, Treatment, and Complications

ERIC Educational Resources Information Center

Conlon, Helen Acree

2007-01-01

It has been estimated that at least one half of the population will experience some type of bite in their lifetime. Human bites are the third leading cause of all bites seen in hospital emergency departments after dog and cat bites. Human bites can be the source of exposure to body fluids, transmission of communicable diseases, infections ranging…

Monkey Bites among US Military Members, Afghanistan, 2011

PubMed Central

Baker, Katheryn A.

2012-01-01

Bites from Macaca mulatta monkeys, native to Afghanistan, can cause serious infections. To determine risk for US military members in Afghanistan, we reviewed records for September–December 2011. Among 126 animal bites and exposures, 10 were monkey bites. Command emphasis is vital for preventing monkey bites; provider training and bite reporting promote postexposure treatment. PMID:23017939

The relationship between oral tori and bite force.

PubMed

Jeong, Chan-Woo; Kim, Kyung-Ho; Jang, Hyo-Won; Kim, Hye-Sun; Huh, Jong-Ki

2018-01-12

Objective The relationship between bite force and torus palatinus or mandibularis remains to be explained. The major aim of this study was to determine the correlation between bite force and oral tori. Methods The bite force of 345 patients was measured with a bite force recorder; impressions of the shape and size of the oral tori were taken on plaster models prior to orthodontic treatments. Subsequently, the relationship between oral tori and bite force was analyzed. Results The size, shape, and incidence of torus palatinus was not significantly correlated with bite force. However, the size of torus mandibularis increased significantly in proportion to the bite force (p = 0.020). The occurrence of different types of oral tori was not correlated with the bite force. Discussion The size of torus mandibularis provides information about bite force and can thus be used to clinically assess occlusal stress.

Dog bite injuries to humans and the use of breed-specific legislation: a comparison of bites from legislated and non-legislated dog breeds.

PubMed

Creedon, Nanci; Ó'Súilleabháin, Páraic S

2017-01-01

The primary objective of this study was to investigate if differences in dog bite characteristics exist amongst legislated and non-legislated dog breeds listed under breed-specific legislation in Ireland (age when bitten, anatomical bite locations, triggers for biting, victim's relationship with the dog, geographical location and owner presence, history of aggression, reporting bite incident to authorities, medical treatment required following the bite, and type of bite inflicted). A second objective of the current study was to investigate dog control officer's enforcement and perceptions of current legislation. Data for statistical analyses were collated through a nationally advertised survey, with Pearson Chi-square and Fisher's Exact Test statistical methods employed for analyses. A total of 140 incident surveys were assessed comprising of non-legislated ( n  = 100) and legislated ( n  = 40) dog bite incidents. Legislated breeds were significantly more likely to be perceived as aggressive and less fearful as triggers for biting compared to non-legislated breeds ( P  = 0.003). Non-legislated breeds were more likely to inflict a bite with the owner present on own property and on a business premises compared to legislated breeds ( P  = 0.036). Non-legislated breeds were more likely to not be reported to the authorities before ( P  = 0.009), and after ( P  = 0.032) the bite occurred compared to legislated breeds. There were no significant differences observed between both groups for; age when the victim was bitten, bite location, relationship with the dog, history of aggression, outcome for the dog, if the dog bit again, and seeing a professional trainer or behaviourist. No significant difference was observed between both legislated and non-legislated groups for medical treatment required following the bite, and the type of bite inflicted. The present study results did not observe evidence of any differences between legislated and non-legislated for both the medical treatment to victims required following the bite, and the type of bite inflicted. The significant differences in bites being reported to authorities, perceived triggers for biting, and biting locations suggests distinctly differing perceptions relating to risk between legislated and non-legislated dog breeds. Further consequences relating to the introduction of breed-specific legislation in Ireland are discussed.

Feeding biomechanics and theoretical calculations of bite force in bull sharks (Carcharhinus leucas) during ontogeny.

PubMed

Habegger, Maria L; Motta, Philip J; Huber, Daniel R; Dean, Mason N

2012-12-01

Evaluations of bite force, either measured directly or calculated theoretically, have been used to investigate the maximum feeding performance of a wide variety of vertebrates. However, bite force studies of fishes have focused primarily on small species due to the intractable nature of large apex predators. More massive muscles can generate higher forces and many of these fishes attain immense sizes; it is unclear how much of their biting performance is driven purely by dramatic ontogenetic increases in body size versus size-specific selection for enhanced feeding performance. In this study, we investigated biting performance and feeding biomechanics of immature and mature individuals from an ontogenetic series of an apex predator, the bull shark, Carcharhinus leucas (73-285cm total length). Theoretical bite force ranged from 36 to 2128N at the most anterior bite point, and 170 to 5914N at the most posterior bite point over the ontogenetic series. Scaling patterns differed among the two age groups investigated; immature bull shark bite force scaled with positive allometry, whereas adult bite force scaled isometrically. When the bite force of C. leucas was compared to those of 12 other cartilaginous fishes, bull sharks presented the highest mass-specific bite force, greater than that of the white shark or the great hammerhead shark. A phylogenetic independent contrast analysis of anatomical and dietary variables as determinants of bite force in these 13 species indicated that the evolution of large adult bite forces in cartilaginous fishes is linked predominantly to the evolution of large body size. Multiple regressions based on mass-specific standardized contrasts suggest that the evolution of high bite forces in Chondrichthyes is further correlated with hypertrophication of the jaw adductors, increased leverage for anterior biting, and widening of the head. Lastly, we discuss the ecological significance of positive allometry in bite force as a possible "performance gain" early in the life history of C. leucas. Copyright © 2012 Elsevier GmbH. All rights reserved.

The Effect of Cholesterol on the Binding and Insertion of Cytochrome b5 into Liposomes of Phosphatidylcholines

DTIC Science & Technology

1993-09-30

cholesterol. Hyslop et al. (1990) I by examining the theoretical molar attraction constants of the various fatty acyl chain and sterol structural groups...multilamellar vesicles (Copeland and McConnel, 1980 ). The "ripples" are putative areas of pure phospholipid. As cholesterol content increases, the...becomes maximal between 20-29%, and then decreases beyond 29\\ cholesterol (Melchior eC al., 1980 ). Additionally, X-ray diffraction of DPPC

Partial purification and characterization of a Ca(2+)-dependent protein kinase from pea nuclei

NASA Technical Reports Server (NTRS)

Li, H.; Dauwalder, M.; Roux, S. J.

1991-01-01

Almost all the Ca(2+)-dependent protein kinase activity in nuclei purified from etiolated pea (Pisum sativum, L.) plumules is present in a single enzyme that can be extracted from chromatin by 0.3 molar NaCl. This protein kinase can be further purified 80,000-fold by salt fractionation and high performance liquid chromatography, after which it has a high specific activity of about 100 picomoles per minute per microgram in the presence of Ca2+ and reaches half-maximal activation at about 3 x 10(-7) molar free Ca2+, without calmodulin. It is a monomer with a molecular weight near 90,000. It can efficiently use histone III-S, ribosomal S6 protein, and casein as artificial substrates, but it phosphorylates phosvitin only weakly. Its Ca(2+)-dependent kinase activity is half-maximally inhibited by 0.1 millimolar chlorpromazine, by 35 nanomolar K-252a and by 7 nanomolar staurosporine. It is insensitive to sphingosine, an inhibitor of protein kinase C, and to basic polypeptides that block other Ca(2+)-dependent protein kinases. It is not stimulated by exogenous phospholipids or fatty acids. In intact isolated pea nuclei it preferentially phosphorylates several chromatin-associated proteins, with the most phosphorylated protein band being near the same molecular weight (43,000) as a nuclear protein substrate whose phosphorylation has been reported to be stimulated by phytochrome in a calcium-dependent fashion.

Descriptive epidemiology of animal bites in Indiana, 1990-92--a rationale for intervention.

PubMed Central

Sinclair, C L; Zhou, C

1995-01-01

Animal bites are a reality of life throughout the world. They arise out of an imperfect relationship with domestic animals and wildlife. Most bite injuries are preventable. The principal approaches to community-wide bite prevention programs include reducing the number of domestic animals roaming in the community (animal control) and teaching people to refrain from behaviors likely to provoke bites. This article addresses the epidemiologic basis and justification for a bite prevention program targeted toward children. Animal bite data from Indiana for the years 1990, 1991, and 1992 were analyzed for trends that might suggest opportunities for preventive intervention. Bites inflicted by humans were not included in this data base. Children of all age groups were disproportionately affected, with the highest incidence in the 5-9 year age group. The dog and the cat were the most commonly reported biting animals. Wild and pet rodents were the next most frequent biting group. The bites most frequently reported from nonrodent wild animals were inflicted by raccoons. The incidence of animal bites in children peaked during the spring (April-June). Boys were bitten at a higher rate than girls, but this difference between the sexes narrows with age and was not noted in the adult population. Residents of urban counties (population greater than 100,000) had higher reported bite rates than residents of nonurban counties. PMID:7838946

Occlusal status and prevalence of occlusal malocclusion traits among 9-year-old schoolchildren.

PubMed

Lux, Christopher J; Dücker, Britta; Pritsch, Maria; Komposch, Gerda; Niekusch, Uwe

2009-06-01

The aim of this study was to provide detailed information concerning clinically relevant occlusal traits and the prevalence of occlusal anomalies in an orthodontically relevant period of dental development. Four hundred and ninety-four German schoolchildren (237 males and 257 females), median age 9 years, were orthodontically examined. Overjet and overbite were measured to the nearest 0.5 mm, and sagittal molar relationships were registered clinically to the nearest quarter unit. In addition, crossbites, scissor bites, and midline displacements were evaluated. Descriptive statistics was complemented by testing gender differences and differences between groups with Class I and Class II anomalies (Mann-Whitney U-test) as well as a statistical evaluation of differences between the three dental stages (Kruskal-Wallis test). Overjet exhibited an extreme range between -2 and 12 mm (median values 3-3.5 mm). An increased overjet was more prevalent than a reduced or reverse overjet, and a severely increased overjet greater than 6 mm was a common finding affecting around 5-10 per cent of the children. Similarly, overbite showed considerable variations of between -1 and 9 mm (medians 3-3.5 mm) and males exhibited a significantly larger overbite than females. In Class II malocclusion subjects, overbite was significantly enlarged (on average between 0.5 and 1 mm) when compared with those with a Class I malocclusion. Traumatic contact of the gingiva affected every 14th child. A Class II molar relationship of three-quarter units or more was a frequent finding affecting more than one child in five. In addition, at 9 years of age, 3 per cent of the children exhibited a Class III molar relationship of at least a half unit. The wide range of orthodontically relevant occlusal traits found in the present study underlines the need for orthodontic screening at 9 years of age (or earlier).

Signal Amplification in Field Effect-Based Sandwich Enzyme-Linked Immunosensing by Tuned Buffer Concentration with Ionic Strength Adjuster.

PubMed

Kumar, Satyendra; Kumar, Narendra; Panda, Siddhartha

2016-04-01

Miniaturization of the sandwich enzyme-based immunosensor has several advantages but could result in lower signal strength due to lower enzyme loading. Hence, technologies for amplification of the signal are needed. Signal amplification in a field effect-based electrochemical immunosensor utilizing chip-based ELISA is presented in this work. First, the molarities of phosphate buffer saline (PBS) and concentrations of KCl as ionic strength adjuster were optimized to maximize the GOx glucose-based enzymatic reactions in a beaker for signal amplification measured by change in the voltage shift with an EIS device (using 20 μl of solution) and validated with a commercial pH meter (using 3 ml of solution). The PBS molarity of 100 μM with 25 mM KCl provided the maximum voltage shift. These optimized buffer conditions were further verified for GOx immobilized on silicon chips, and similar trends with decreased PBS molarity were obtained; however, the voltage shift values obtained on chip reaction were lower as compared to the reactions occurring in the beaker. The decreased voltage shift with immobilized enzyme on chip could be attributed to the increased Km (Michaelis-Menten constant) values in the immobilized GOx. Finally, a more than sixfold signal enhancement (from 8 to 47 mV) for the chip-based sandwich immunoassay was obtained by altering the PBS molarity from 10 to 100 μM with 25 mM KCl.

A novel sensor for bite force determinations.

PubMed

Fernandes, Cláudio P; Glantz, Per Olof J; Svensson, Stig A; Bergmark, Anders

2003-03-01

The clinical usefulness, accuracy and precision of a novel bite force sensor based on force sensing resistors were tested in six subjects wearing maxillary removable partial dentures retained by conical crowns. The surfaces of the sensor were manufactured in a silicone material that had mechanical properties similar to those of tough foodstuffs. In two separate series of standardized bite force tests, submaximum force levels were recorded with the sensor and with a strain gaged bite fork. Subjects were assisted in the loading tests with visual feedback instrumentation. Reliability estimates for the bite force sensor were calculated in order to show their reproducibility. Strain gages attached to the prostheses were used to determine the pattern of force distribution during loading tests. The bite force results obtained with the new bite force sensor and with the bite fork were analyzed with ANOVA and Scheffés tests. The strain patterns registered with strain gages were analyzed with F-test. The bite force sensor and the bite fork transducer showed no statistically significant differences in respect of intra-individual bite force levels (range 50-300N). The bite forces registered with the new sensor were dependent on the loading position (p<0.05), sex (p<0.05) and test subject (p<0.05). The reliability of the new sensor for submaximum bite forces was calculated to be 93%. Strain gage results showed that the new sensor generated strain patterns of less variance (p<0.05) than the bite fork and therefore allowed for higher precision during biting tests. The presented instrument has such clinical merits, as to favor its use in experimental clinical studies on the biomechanics of prosthetic appliances.

Relationship between Bruxism and Malocclusion among Preschool Children in Isfahan

PubMed Central

Ghafournia, Maryam; Hajenourozali Tehrani, Maryam

2012-01-01

Background and aims Bruxism is defined as a habitual nonfunctional forceful contact between occlusal tooth surfaces. In younger children bruxism may be a consequence of the masticatory neuromuscular system immaturity. The aim of this study was to assess the prevalence of bruxism and investigate the relationship between occlusal factors and bruxism among preschool children. Materials and methods In this cross-sectional survey, 400 3-6-year-old children were selected randomly from different preschools in Isfahan, Iran. The subjects were divided into two groups of bruxers and non-bruxers as determined by the clinical examination and their parents’ reports. The examiner recorded the primary canines (Class I, Class II, and Class III) and molars (mesial step, distal step, flash terminal plane) relationship, existence of anterior and posterior crossbite, open and deep bite. Also, rotated teeth, food impaction, sharp tooth edges, high restorations, extensive tooth caries, and painful teeth (categorized as irritating tooth conditions) were evaluated. The relationship between bruxism and occlusal factors and irritating tooth conditions was evaluated with chi-square test. Results Bruxism was seen in 12.75% of the subjects. Statistically significant relationships existed between bruxism and some occlusal factors, such as flash terminal plane (P = 0.023) and mesial step (P = 0.001) and also, between food impaction, extensive tooth caries, tooth pain, sharp tooth edge and bruxism. Conclusion The results showed significant relationship of bruxism with primary molar relationships and irritating tooth conditions among preschool children. PMID:23277860

Bite force measurements with hard and soft bite surfaces.

PubMed

Serra, C M; Manns, A E

2013-08-01

Bite force has been measured by different methods and over a wide variety of designs. In several instruments, the fact that bite surface has been manufactured with stiff materials might interfere in obtaining reliable data, by a more prompt activation of inhibitory reflex mechanisms. The purpose of this study was to compare the maximum voluntary bite force measured by a digital occlusal force gauge (GM10 Nagano Keiki, Japan) between different opponent teeth, employing semi-hard or soft bite surfaces. A sample of 34 young adults with complete natural dentition was studied. The original semi-hard bite surface was exchanged by a soft one, made of leather and rubber. Maximum voluntary bite force recordings were made for each tooth group and for both bite surfaces. Statistical analyses (Student's t-test) revealed significant differences, with higher scores while using the soft surface across sexes and tooth groups (P < 0·05). Differential activation of periodontal mechanoreceptors of a specific tooth group is mainly conditioned by the hardness of the bite surface; a soft surface induces greater activation of elevator musculature, while a hard one induces inhibition more promptly. Thus, soft bite surfaces are recommended for higher reliability in maximum voluntary bite force recordings. © 2013 John Wiley & Sons Ltd.

Bite Forces and Their Measurement in Dogs and Cats.

PubMed

Kim, Se Eun; Arzi, Boaz; Garcia, Tanya C; Verstraete, Frank J M

2018-01-01

Bite force is generated by the interaction of the masticatory muscles, the mandibles and maxillae, the temporomandibular joints (TMJs), and the teeth. Several methods to measure bite forces in dogs and cats have been described. Direct in vivo measurement of a bite in dogs has been done; however, bite forces were highly variable due to animal volition, situation, or specific measurement technique. Bite force has been measured in vivo from anesthetized dogs by electrical stimulation of jaw adductor muscles, but this may not be reflective of volitional bite force during natural activity. In vitro bite forces have been estimated by calculation of the force produced using mechanical equations representing the jaw adductor muscles and of the mandible and skull structure Bite force can be estimated in silico using finite element analysis (FEA) of the computed model of the anatomical structures. FEA can estimate bite force in extinct species; however, estimates may be lower than the measurements in live animals and would have to be validated specifically in domestic dogs and cats to be reliable. The main factors affecting the bite forces in dogs and cats are body weight and the skull's morphology and size. Other factors such as oral pain, TMJ disorders, masticatory muscle atrophy, and malocclusion may also affect bite force. Knowledge of bite forces in dogs and cats is essential for various clinical and research fields such as the development of implants, materials, and surgical techniques as well as for forensic medicine. This paper is a summary of current knowledge of bite forces in dogs and cats, including the effect of measurement methods and of other factors.

Dog bites in a U.S. county: age, body part and breed in paediatric dog bites.

PubMed

Ramgopal, Sriram; Brungo, Lauren Bealafeld; Bykowski, Michael R; Pitetti, Raymond D; Hickey, Robert W

2018-05-01

To compare characteristics of gender, age, body part and breed in dog bites. We reviewed 14 956 dog bites (4195 paediatric) reported to the Allegheny County Health Department, USA, between 2007 and 2015. Using predefined age groups, we performed linear regression to assess for subject age and bite frequency and used binary logistic regression to evaluate for differences in gender and body part. We used chi-squared test with Bonferroni correction to evaluate for differences in reported breeds with age. There was a negative correlation (-0.80, r 2 = 0.64) between age and bite frequency. Children 0-3 years had a higher odds ratio (OR) of bites to the face [21.12, 95% confidence interval (CI): 17.61-25.33] and a lower OR of bites to the upper (OR: 0.14, 95% CI: 0.12-0.18) and lower (OR: 0.19, 95% CI: 0.14-0.27) extremities. 'Pit bulls' accounted for 27.2% of dog bites and were more common in children 13-18 years (p < 0.01). Shih-Tzu bites were more common in children three years of age and younger (p < 0.01). Dog bites occur with higher frequency at younger ages, and head and neck injuries are more common in younger children. Pit bull bites are more common in adolescents and Shih-Tzu bites more common in younger children. ©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Effects of Bite Count Feedback from a Wearable Device and Goal Setting on Consumption in Young Adults.

PubMed

Jasper, Phillip W; James, Melva T; Hoover, Adam W; Muth, Eric R

2016-11-01

New technologies are emerging that may help individuals engage in healthier eating behaviors. One paradigm to test the efficacy of a technology is to determine its effect relative to environment cues that are known to cause individuals to overeat. The purpose of this work was to independently investigate two questions: How does the presence of a technology that provides bite count feedback alter eating behavior? and, How does the presence of a technology that provides bite count feedback paired with a goal alter eating behavior? Two studies investigated these research questions. The first study tested the effects of a large and small plate crossed with the presence or absence of a device that provided bite count feedback on intake. The second study tested the effects of a bite count goal with bite count feedback, again crossed with plate size, on intake. Both studies used a 2×2 between-subjects design. In the first study, 94 subjects (62 women aged 19.0±1.6 years with body mass index [BMI] 23.04±3.6) consumed lunch in a laboratory. The second study examined 99 subjects (56 women aged 18.5±1.5 years with BMI 22.73±2.70) under the same conditions. In both studies subjects consumed a single-course meal, using either a small or large plate. In the first study participants either wore or did not wear an automated bite counting device. In the second study all participants wore the bite counting device and were given either a low bite count goal (12 bites) or a high bite count goal (22 bites). Effect of plate size, feedback, and goal on consumption (grams) and number of bites taken were assessed using 2×2 analyses of variance. As adjunct measures, the effects of serving size, bite size (grams per bite), postmeal satiety, and satiety change were also assessed. In the first study there was a main effect of plate size on grams consumed and number of bites taken such that eating from a large plate led to greater consumption (P=0.001) and a greater number of bites (P=0.001). There was also a main effect of feedback on consumption and number of bites taken such that those who received feedback consumed less (P=0.011) and took fewer bites (P<0.001). In the second study there was a main effect of plate size on consumption such that those eating from a large plate consumed more (P=0.003) but did not take more bites. Further analysis revealed a main effect of goal on number of bites taken such that those who received the low goal took fewer bites (P<0.001) but did not consume less. Providing feedback on the number of bites taken from a wearable intake monitor can reduce overall intake during a single meal. Regarding the first research question, providing feedback significantly reduced intake in both plate size groups and reduced the overall number of bites taken. Regarding the second research question, participants were successful in eating to their goals. However, individuals in the low goal condition appeared to compensate for the restricted goal by taking larger bites, leading to comparable levels of consumption between the low and high goal groups. Hence, the interaction of technology with goals should be considered when introducing a health intervention. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Describing the Relationship between Cat Bites and Human Depression Using Data from an Electronic Health Record

PubMed Central

Hanauer, David A.; Ramakrishnan, Naren; Seyfried, Lisa S.

2013-01-01

Data mining approaches have been increasingly applied to the electronic health record and have led to the discovery of numerous clinical associations. Recent data mining studies have suggested a potential association between cat bites and human depression. To explore this possible association in more detail we first used administrative diagnosis codes to identify patients with either depression or bites, drawn from a population of 1.3 million patients. We then conducted a manual chart review in the electronic health record of all patients with a code for a bite to accurately determine which were from cats or dogs. Overall there were 750 patients with cat bites, 1,108 with dog bites, and approximately 117,000 patients with depression. Depression was found in 41.3% of patients with cat bites and 28.7% of those with dog bites. Furthermore, 85.5% of those with both cat bites and depression were women, compared to 64.5% of those with dog bites and depression. The probability of a woman being diagnosed with depression at some point in her life if she presented to our health system with a cat bite was 47.0%, compared to 24.2% of men presenting with a similar bite. The high proportion of depression in patients who had cat bites, especially among women, suggests that screening for depression could be appropriate in patients who present to a clinical provider with a cat bite. Additionally, while no causative link is known to explain this association, there is growing evidence to suggest that the relationship between cats and human mental illness, such as depression, warrants further investigation. PMID:23936453

Bacteria isolated from conspecific bite wounds in Norway and black rats: implications for rat bite-associated infections in people.

PubMed

Himsworth, Chelsea G; Zabek, Erin; Tang, Patrick; Parsons, Kirbee L; Koehn, Martha; Jardine, Claire M; Patrick, David M

2014-02-01

Bites associated with wild and domestic Norway and black rats (Rattus norvegicus and Rattus rattus) may have a variety of health consequences in people. Bite-related infections are among the most significant of these consequences; however, there is little data on the infectious agents that can be transmitted from rats to people through biting. This is problematic because without an accurate understanding of bite-related infection risks, it is difficult for health professionals to evaluate the adequacy of existing guidelines for empirical therapy. The objectives of this study were to increase our knowledge of the bacterial species associated with rat bites by studying bite wounds that wild rats inflict upon one another and to review the literature regarding rat bites and bite wound management. Wild Norway and black rats (n=725) were trapped in Vancouver, Canada, and examined for bite wounds in the skin. All apparently infected wounds underwent aerobic and anaerobic culture, and isolated bacteria were identified. Thirty-six rats had bite wound-related infections, and approximately 22 different species of bacteria belonging to 18 genera were identified. Staphylococcus aureus was the most common isolate; however, the majority of infections (72.5%) were polymicrobial. Rat bites can result in infection with a number of aerobic and anaerobic Gram-positive and Gram-negative bacteria. In humans, these wounds are best managed through early recognition and cleansing. The benefit of prophylactic antimicrobial treatment is debatable, but given the deep puncturing nature of rodent bites, we suggest that they should be considered a high risk for infection. Antibiotics selected should include coverage for a broad range of bacterial species.

Annual incidence of snake bite in rural bangladesh.

PubMed

Rahman, Ridwanur; Faiz, M Abul; Selim, Shahjada; Rahman, Bayzidur; Basher, Ariful; Jones, Alison; d'Este, Catherine; Hossain, Moazzem; Islam, Ziaul; Ahmed, Habib; Milton, Abul Hasnat

2010-10-26

Snake bite is a neglected public health problem in the world and one of the major causes of mortality and morbidity in many areas, particularly in the rural tropics. It also poses substantial economic burdens on the snake bite victims due to treatment related expenditure and loss of productivity. An accurate estimate of the risk of snake bite is largely unknown for most countries in the developing world, especially South-East Asia. We undertook a national epidemiological survey to determine the annual incidence density of snake bite among the rural Bangladeshi population. Information on frequency of snake bite and individuals' length of stay in selected households over the preceding twelve months was rigorously collected from the respondents through an interviewer administered questionnaire. Point estimates and confidence intervals of the incidence density of snake bite, weighted and adjusted for the multi-stage cluster sampling design, were obtained. Out of 18,857 study participants, over one year a total of 98 snake bites, including one death were reported in rural Bangladesh. The estimated incidence density of snake bite is 623.4/100,000 person years (95% C I 513.4-789.2/100,000 person years). Biting occurs mostly when individuals are at work. The majority of the victims (71%) receive snake bites to their lower extremities. Eighty-six percent of the victims received some form of management within two hours of snake bite, although only three percent of the victims went directly to either a medical doctor or a hospital. Incidence density of snake bite in rural Bangladesh is substantially higher than previously estimated. This is likely due to better ascertainment of the incidence through a population based survey. Poor access to health services increases snake bite related morbidity and mortality; therefore, effective public health actions are warranted.

A placebo controlled clinical trial investigating the efficacy of a homeopathic after-bite gel in reducing mosquito bite induced erythema.

PubMed

Hill, N; Stam, C; Tuinder, S; van Haselen, R A

1995-01-01

A randomised, placebo controlled clinical trial was conducted to examine the efficacy of a homeopathic after-bite gel in the symptomatic relief of mosquito bites. Sixty eight healthy volunteers were bitten under laboratory conditions by Aedes aegypti mosquitoes at three spots, on the ventral aspect of the forearm. One bite was treated with the homeopathic after-bite gel, another bite with a placebo gel which was identical in appearance and smell to the homeopathic after-bite gel, and the third bite remained untreated. Immediately after the bites and 1, 3, 6, 26 and 31 hours post-bite, the length and width of the erythema were measured with a calliper, and photographs were taken of the bite sites from which the size of the erythema was subsequently determined. This was followed by assessment of the extent of itching with a verbal analogue scale, and finally treatment took place. For each spot the total erythema was calculated as the area under the plotted curve of the erythema at different time points (mm2*h) and the total sum of the itch scores was determined. For the bites treated with the homeopathic after-bite gel the median total erythema was 10.500 mm2*h. For the spots treated with the placebo gel and the untreated spots the median total erythema was 12.900 mm2*h and 13.300 mm2*h, respectively. The difference between the spots treated with the homeopathic after-bite gel and the untreated spots came close to significance (two-tailed P = 0.06), which was not the case for the difference between the spots treated with the homeopathic after-bite gel and the spots treated with placebo gel (P = 0.13). After pooling the data of a very similar previous pilot study and the present study (ntotal = 83), the homeopathic after-bite gel was significantly superior to no treatment (two-tailed P = 0.003) as well as to placebo gel (two-tailed P = 0.03). Comparing itching after the three treatments, no significant differences could be demonstrated. The extent of itching was positively correlated with the area of the erythema (r = 0.63). Treatment of mosquito bites with the homeopathic after-bite gel will reduce the erythema compared to no treatment. Comparison with the placebo gel suggests it is the plant extracts which are the active components of this gel.

[Comparison of bite marks and teeth features using 2D and 3D methods].

PubMed

Lorkiewicz-Muszyńska, Dorota; Glapiński, Mariusz; Zaba, Czesław; Łabecka, Marzena

2011-01-01

The nature of bite marks is complex. They are found at the scene of crime on different materials and surfaces - not only on human body and corpse, but also on food products and material objects. Human bites on skin are sometimes difficult to interpret and to analyze because of the specific character of skin--elastic and distortable--and because different areas of human body have different surfaces and curvatures. A bite mark left at the scene of crime can be a highly helpful way to lead investigators to criminals. The study was performed to establish: 1) whether bite marks exhibit variations in the accuracy of impressions on different materials, 2) whether it is possible to use the 3D method in the process of identifying an individual based on the comparison of bite marks revealed at the scene, and 3D scans of dental casts, 3) whether application of the 3D method allows for elimination of secondary photographic distortion of bite marks. The authors carried out experiments on simulated cases. Five volunteers bit various materials with different surfaces. Experimental bite marks were collected with emphasis on differentiations of materials. Subsequently, dental impressions were taken from five volunteers in order to prepare five sets of dental casts (the maxilla and mandible. The biting edges of teeth were impressed in wax to create an imprint. The samples of dental casts, corresponding wax bite impressions and bite marks from different materials were scanned with 2D and 3D scanners and photographs were taken. All of these were examined in detail and then compared using different methods (2D and 3D). 1) Bite marks exhibit variations in accuracy of impression on different materials. The most legible reproduction of bite marks was seen on cheese. 2) In comparison of bite marks, the 3D method and 3D scans of dental casts are highly accurate. 3) The 3D method helps to eliminate secondary photographic distortion of bite marks.

Spatial and temporal variation in biting rates and parasite transmission potentials of onchocerciasis vectors in Ecuador.

PubMed

Vieira, J C; Brackenboro, L; Porter, C H; Basáñez, M-G; Collins, R C

2005-03-01

The influence of spatial and temporal factors on onchocerciasis transmission by Simulium exiguum s.l. and S. quadrivittatum in Ecuador was investigated to help develop sampling protocols for entomological surveillance of ivermectin programmes. Flies were collected in alternate months (November 1995-November 1996) at four sites each in the hyperendemic communities of San Miguel and El Tigre. A fixed-effects analysis of variance was used to explore the influence on vector abundance of locality, site, month and hour. Infectivity rates detected by dissection and PCR assays were compared. Simulium exiguum s.l. predominated at El Tigre (75%) whereas S. quadrivittatum prevailed at San Miguel (62%). Vector abundance was highest on river banks and outside houses. Biting and infection rates peaked from March to July. Hourly activity patterns were bimodal in S. exiguum but unimodal in S. quadrivittatum. Annual transmission potentials (ATP) for both species combined were 385 and 733 third stage larvae/person in San Miguel and El Tigre respectively, with S. exiguum accounting for 80% of the combined ATP at both localities. We recommend protocols that may maximize detection of parasite transmission. Infection rates thus obtained must be linked with vector density estimates to assess meaningfully host exposure as treatment progresses.

Comparison of Preferred Bite Sites between Mites and Ticks on Humans in Korea

PubMed Central

Jang, Mi-Sun; Kim, Choon-Mee; Kim, Dong-Min; Yoon, Na Ra; Han, Mi Ah; Kim, Hyun-Kuk; Oh, Won Sup; Yoon, Hee-Jung; Wie, Seong-Heon; Hur, Jian

2016-01-01

Identification of mite and tick bite sites provides important clinical information. The predominant mite species in Korea associated with scrub typhus are Leptotrombidium pallidum and Leptotrombidium scutellare. The most abundant tick species is Haemaphysalis longicornis. To date, there has been no comparative study on preferred bite sites between mites and ticks in humans. This study included a review of medical records and a field study. For mite bite sites, eschars were checked on 506 patients with scrub typhus, confirmed by indirect immunofluorescence assay or nested polymerase chain reaction on the 56-kDa type-specific antigen gene of Orientia tsutsugamushi. Tick bite sites were identified and marked on a diagram for 91 patients who experienced tick bites within the previous year through a field epidemiological investigation. The mite and tick bite sites in Koreans were compared. The most frequently observed mite bite sites were the anterior chest, including the axillae (29.1%) and the abdominal region, including the inguinal area (26.1%). Tick bite sites were most frequent on the lower extremities (33.0%), followed by the abdominal region, including the inguinal area (26.4%), and upper extremities (26.4%). The distribution was significantly different between mite and tick bite sites (P < 0.001). There was a statistically significant difference in the mite bite (P = 0.001), but not tick bite sites (P = 0.985), between men and women. This is the first report on the differences between tick and mite bite sites, and may help clinicians reach a rapid diagnosis of mite- or tick-borne infection. PMID:27645781

First report of clinical presentation of a bite by a running spider, Philodromus sp. (Araneae: Philodromidae), with recommendations for spider bite management.

PubMed

Coetzee, Maureen; Dippenaar, Ansie; Frean, John; Hunt, Richard H

2017-06-30

This article describes the clinical progression of symptoms over a period of 5 days of a bite inflicted by a Philodromus sp. spider. Commonly known as 'running spiders', these are not considered to be harmful to humans. This report, however, is the first description of an actual bite by a member of this group of spiders showing cytotoxic envenomation. Management of the bites should be as recommended for other cytotoxic spider bites.

A new bite block for panoramic radiographs of anterior edentulous patients: A technical report.

PubMed

Park, Jong-Woong; Symkhampha, Khanthaly; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul

2015-06-01

Panoramic radiographs taken using conventional chin-support devices have often presented problems with positioning accuracy and reproducibility. The aim of this report was to propose a new bite block for panoramic radiographs of anterior edentulous patients that better addresses these two issues. A new panoramic radiography bite block similar to the bite block for dentulous patients was developed to enable proper positioning stability for edentulous patients. The new bite block was designed and implemented in light of previous studies. The height of the new bite block was 18 mm and to compensate for the horizontal edentulous space, its horizontal width was 7 mm. The panoramic radiographs using the new bite block were compared with those using the conventional chin-support device. Panoramic radiographs taken with the new bite block showed better stability and bilateral symmetry than those taken with the conventional chin-support device. Patients also showed less movement and more stable positioning during panoramic radiography with the new bite block. Conventional errors in panoramic radiographs of edentulous patients could be caused by unreliability of the chin-support device. The newly proposed bite block for panoramic radiographs of edentulous patients showed better reliability. Further study is required to evaluate the image quality and reproducibility of images with the new bite block.

Human bites - self-care

MedlinePlus

... this page: //medlineplus.gov/ency/patientinstructions/000736.htm Human bites - self-care To use the sharing features ... at higher risk for infection. How to Prevent Human Bites Prevent bites by: Teaching young children not ...

Bites and Scratches (For Parents)

MedlinePlus

... pet (in kids, most animal bites are from dogs ) or a creature from the wild, scratches and ... First Aid: Animal Bites Cat Scratch Disease Preventing Dog Bites Rabies Cuts, Scratches, and Abrasions Dogs and ...

Insect Bites and Stings

MedlinePlus

Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, ...

Spider Bites (For Parents)

MedlinePlus

... Videos for Educators Search English Español First Aid: Spider Bites KidsHealth / For Parents / First Aid: Spider Bites ... rare. Signs and Symptoms Of a brown recluse spider bite: red blister in the center with surrounding ...

Common errors observed at the American Board of Orthodontics clinical examination.

PubMed

Chung, Chun-Hsi; Tadlock, Larry P; Barone, Nicholas; Pangrazio-Kulbersh, Valmy; Sabott, David G; Foley, Patrick F; Trulove, Timothy S; Park, Jae Hyun; Dugoni, Steven A

2017-08-01

The American Board of Orthodontics has developed tools to help examinees select patients to be used for the Board examination. The Case Management Form can be used to evaluate aspects of a patient's treatment that cannot be measured by other tools. The Case Management Form is a structured treatment-neutral assessment of orthodontic objectives and outcomes associated with a patient's treatment. Despite the availability of this form, examiners continue to see problems, including lack of attention to finishing details, inappropriate treatment objectives, excessive proclination of mandibular incisors due to treatment mechanics, excessive expansion of mandibular intercanine width, closing skeletal open bite with extrusion of anterior teeth leading to excessive gingival display, and failure to recognize the importance of controlling the eruption or extrusion of molars during treatment. In addition, some examinees exhibit a lack of understanding of proper cephalometric tracing and superimposition techniques, which lead to improper interpretation of cephalometric data and treatment outcomes. Copyright © 2017. Published by Elsevier Inc.

Modified protrusion arch for anterior crossbite correction - a case report.

PubMed

Roy, Abhishek Singha; Singh, Gulshan Kr; Tandon, Pradeep; Chaudhary, Ramsukh

2013-01-01

Borderline and mild skeletal Class III relationships in adult patients are usually treated by orthodontic camouflage. Reasonably rood results have been achieved with nonsurgical teatment of anterior crossbite. Class III malocclusion may be associated with mandibular prognathism, maxillary retrognathism, or both. Class III maxillary retrognathism generally involves anterior crossbite, which must be opened if upper labial brackets are to be bonded. If multiple teeth are in crossbite, after opening the bite usual step is to ligate forward or advancement arch made of 0.018" or 0.020" stainless steel or NiTi wire main arch that must be kept separated 2 mm from the slot ofupper incisor braces. Two stops or omegas are made 1 mm mesial to the tubes of the molar bands that will impede main arch from slipping,and in this manner the arch will push the anterior teeth forward Here we have fabricated a modified multiple loop protrusion arch to correct an anterior crossbite with severe crowding that was not amenable to correct by advancement arches.

Wet-chemical synthesis of different bismuth telluride nanoparticles using metal organic precursors - single source vs. dual source approach.

PubMed

Bendt, Georg; Weber, Anna; Heimann, Stefan; Assenmacher, Wilfried; Prymak, Oleg; Schulz, Stephan

2015-08-28

Thermolysis of the single source precursor (Et2Bi)2Te in DIPB at 80 °C yielded phase-pure Bi4Te3 nanoparticles, while mixtures of Bi4Te3 and elemental Bi were formed at higher temperatures. In contrast, cubic Bi2Te particles were obtained by thermal decomposition of Et2BiTeEt in DIPB. Moreover, a dual source approach (hot injection method) using the reaction of Te(SiEt3)2 and Bi(NMe2)3 was applied for the synthesis of different pure Bi-Te phases including Bi2Te, Bi4Te3 and Bi2Te3, which were characterized by PXRD, REM, TEM and EDX. The influence of reaction temperature, precursor molar ratio and thermolysis conditions on the resulting material phase was verified. Moreover, reactions of alternate bismuth precursors such as Bi(NEt2)3, Bi(NMeEt)3 and BiCl3 with Te(SiEt3)2 were investigated.

Bacteria Isolated from Conspecific Bite Wounds in Norway and Black Rats: Implications for Rat Bite–Associated Infections In People

PubMed Central

Zabek, Erin; Tang, Patrick; Parsons, Kirbee L.; Koehn, Martha; Jardine, Claire M.; Patrick, David M.

2014-01-01

Abstract Bites associated with wild and domestic Norway and black rats (Rattus norvegicus and Rattus rattus) may have a variety of health consequences in people. Bite-related infections are among the most significant of these consequences; however, there is little data on the infectious agents that can be transmitted from rats to people through biting. This is problematic because without an accurate understanding of bite-related infection risks, it is difficult for health professionals to evaluate the adequacy of existing guidelines for empirical therapy. The objectives of this study were to increase our knowledge of the bacterial species associated with rat bites by studying bite wounds that wild rats inflict upon one another and to review the literature regarding rat bites and bite wound management. Wild Norway and black rats (n=725) were trapped in Vancouver, Canada, and examined for bite wounds in the skin. All apparently infected wounds underwent aerobic and anaerobic culture, and isolated bacteria were identified. Thirty-six rats had bite wound–related infections, and approximately 22 different species of bacteria belonging to 18 genera were identified. Staphylococcus aureus was the most common isolate; however, the majority of infections (72.5%) were polymicrobial. Rat bites can result in infection with a number of aerobic and anaerobic Gram-positive and Gram-negative bacteria. In humans, these wounds are best managed through early recognition and cleansing. The benefit of prophylactic antimicrobial treatment is debatable, but given the deep puncturing nature of rodent bites, we suggest that they should be considered a high risk for infection. Antibiotics selected should include coverage for a broad range of bacterial species. PMID:24528094

Rat Bite Fever

MedlinePlus

... Rat Bite Fever Health Issues Listen Español Text Size Email Print Share Rat Bite Fever Page Content Article Body Rat-bite fever is a disease that occurs in humans who have been bitten by an infected rat ...

Insect Repellents: Protect Your Child from Insect Bites

MedlinePlus

... Print Share Choosing an Insect Repellent for Your Child Page Content Mosquitoes, biting flies, and tick bites ... container with you. Other Ways to Protect Your Child from Insect Bites While you can’t prevent ...

Utilization of acetone-butanol-ethanol-water mixture obtained from biomass fermentation as renewable feedstock for hydrogen production via steam reforming: Thermodynamic and energy analyses.

PubMed

Kumar, Brajesh; Kumar, Shashi; Sinha, Shishir; Kumar, Surendra

2018-08-01

A thermodynamic equilibrium analysis on steam reforming process to utilize acetone-butanol-ethanol-water mixture obtained from biomass fermentation as biorenewable fuel has been performed to produce clean energy carrier H 2 via non-stoichiometric approach namely Gibbs free energy minimization method. The effect of process variables such as temperature (573-1473 K), pressure (1-10 atm), and steam/fuel molar feed ratio (F ABE  = 5.5-12) have been investigated on equilibrium compositions of products, H 2 , CO, CO 2 , CH 4 and solid carbon. The best suitable conditions for maximization of desired product H 2 , suppression of CH 4 , and inhibition of solid carbon are 973 K, 1 atm, steam/fuel molar feed ratio = 12. Under these conditions, the maximum molar production of hydrogen is 8.35 with negligible formation of carbon and methane. Furthermore, the energy requirement per mol of H 2 (48.96 kJ), thermal efficiency (69.13%), exergy efficiency (55.09%), exergy destruction (85.36 kJ/mol), and generated entropy (0.29 kJ/mol.K) have been achieved at same operating conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Annual Incidence of Snake Bite in Rural Bangladesh

PubMed Central

Rahman, Ridwanur; Faiz, M. Abul; Selim, Shahjada; Rahman, Bayzidur; Basher, Ariful; Jones, Alison; d'Este, Catherine; Hossain, Moazzem; Islam, Ziaul; Ahmed, Habib; Milton, Abul Hasnat

2010-01-01

Background Snake bite is a neglected public health problem in the world and one of the major causes of mortality and morbidity in many areas, particularly in the rural tropics. It also poses substantial economic burdens on the snake bite victims due to treatment related expenditure and loss of productivity. An accurate estimate of the risk of snake bite is largely unknown for most countries in the developing world, especially South-East Asia. Methodology/Principal Findings We undertook a national epidemiological survey to determine the annual incidence density of snake bite among the rural Bangladeshi population. Information on frequency of snake bite and individuals' length of stay in selected households over the preceding twelve months was rigorously collected from the respondents through an interviewer administered questionnaire. Point estimates and confidence intervals of the incidence density of snake bite, weighted and adjusted for the multi-stage cluster sampling design, were obtained. Out of 18,857 study participants, over one year a total of 98 snake bites, including one death were reported in rural Bangladesh. The estimated incidence density of snake bite is 623.4 / 100,000 person years (95% C I 513.4–789.2 /100,000 person years). Biting occurs mostly when individuals are at work. The majority of the victims (71%) receive snake bites to their lower extremities. Eighty-six percent of the victims received some form of management within two hours of snake bite, although only three percent of the victims went directly to either a medical doctor or a hospital. Conclusions/Significance Incidence density of snake bite in rural Bangladesh is substantially higher than previously estimated. This is likely due to better ascertainment of the incidence through a population based survey. Poor access to health services increases snake bite related morbidity and mortality; therefore, effective public health actions are warranted. PMID:21049056

A qualitative investigation of the perceptions of female dog-bite victims and implications for the prevention of dog bites.

PubMed

Westgarth, Carri; Watkins, Francine

2015-01-01

Preventing dog bites is an increasingly important public health and political issue with implications for both human and animal health and welfare. Expert opinion is that most bites are preventable. Intervention materials have been designed to educate people on how to assess the body language of dogs, evaluate risk, and take appropriate action. The effectiveness of this approach is rarely evaluated and the incidence of dog bites is thought to be increasing. Is the traditional approach to dog bite prevention working as well as it should? In this novel, small scale qualitative study, the perceptions of victims regarding their dog bite experience were explored in-depth. The study recruited 8 female participants who had been bitten by a dog in the past 5 years. In-depth, one-to-one interviews were conducted, transcribed, and analyzed using thematic analysis. The findings indicate that dog bites may not be as easily preventable as previously presumed, and that education about dog body language may not prevent some types of dog bites. The reasons participants were bitten were multifaceted and complex. In some cases, there was no interaction with the dog before the bite so there was no opportunity to assess the situation and modify behavior around the dog accordingly. Identifying who was to blame, and had responsibility for preventing the bite, was straightforward for the participants in hindsight. Those bitten blamed themselves and/or the dog owner, but not the dog. Most participants already felt they had a theoretical knowledge that would allow them to recognize dog aggression before the dog bite, yet participants, especially those who worked regularly with dogs, routinely believed, "it would not happen to me." We also identified an attitude that bites were "just one of those things," which could also be a barrier prevention initiatives. Rather than being special to the human-canine relationship, the attitudes discovered mirror those found in other areas of injury prevention. A new approach to dog-bite prevention may now be required, drawing on other injury prevention strategies including awareness-raising and minimizing the damage caused by a bite when it happens.

Epidemiological profile of snake-bite cases from Haryana: A five year (2011-2015) retrospective study.

PubMed

Bhargava, Saurabh; Kaur, Ramanjeet; Singh, Rajvinder

2018-02-01

Varieties of venomous snakes inhabit in the world which accidentally take thousands of human lives every year. This severe medical emergency constantly persuades national and international health agencies to look at efficient epidemiological profiling of snake-bite cases for the proper management of this sympathetic problem. Establishing the accurate database of snake-bite in humans from different localities of India may perhaps lack certainty due to few inevitable reasons such as consideration of this problem as less emergent problem in disparity to pesticide poisoning, difficulty in the accessibility to rural and tribal areas where chances of snake-bite remain ceiling, lack of inspiring models of snake-bite management training, reduced reporting system, and pitiable maintenance of hospital data in India. Therefore, the present modest study was carried out to explore valuable information regarding snake-bite problem in Haryana. Factual data on snake-bite incidences happened from 2011 to 2015 were collected from government hospitals and medical institutes of Haryana. This retrospective study disclosed a few characteristic points related to the frequency of snake-bite cases, gender involved, anti-snake venom (ASV) treatment, and numbers of deaths with snake-bite. Records revealed a total of 6555 cases of snake-bite including 130 deaths reported in Haryana during the study period. A significant variation in the occurrence of snake-bite cases was also recorded in different areas of Haryana. There was a huge database of recorded snake-bite cases from government medical institute but district wise survey disclosed the maximum number of snake-bite incidences, especially amongst males from Panchkula. The present study has provided a more updated and comprehensive record of snake-bite from Haryana during 2011-2015. A huge burden of snake-bite amongst human was found in Haryana; hence, the findings of this study purposely enlighten people about the size of this problem in the selected region. However, this study also remained limited due to lack of information on a few important parameters and availability of homogeneous data. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Pattern of maxillary and mandibular proximal enamel thickness at the contact area of the permanent dentition from first molar to first molar.

PubMed

Sarig, Rachel; Vardimon, Alexander D; Sussan, Celine; Benny, Lea; Sarne, Ofer; Hershkovitz, Israel; Shpack, Nir

2015-04-01

Proximal enamel thickness (PET) at the mesial and distal contact areas of the complete permanent dentition has not been previously reported. Anatomic investigation of PET is essential for interproximal reduction treatment. Our objectives were to measure the PETs of the complete maxillary and mandibular dentitions at the contact areas, to compare the PETs of adjacent teeth, and to evaluate the vertical position of each contact area. We evaluated 720 extracted teeth; of these, 109 intact teeth were selected. The mesial and distal contact areas were demarcated, and each tooth was embedded in transparent epoxy resin. Blocks were prepared so that the 2 demarcated contact areas were exposed, and 6 measurements were taken and statistically analyzed. Both jaws showed the same PET pattern characterized by 5 features: PET increased progressively from incisor (0.63 mm) to first molar (1.48 mm). Per tooth, mesial and distal PET did not differ. Total maxillary (26.86 mm) and mandibular (24.52 mm) PETs were similar. Paired PETs at the interproximal interface were similar, with the exception of the lateral incisor-canine interfaces. From incisor to first molar, the contact area becomes located farther gingivally. The existing guideline of maximal 0.5-mm interproximal reduction per 2 adjacent teeth should be kept in the anterior region and could be increased to 1 mm in the posterior region, when an equal amount is removed. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Epidemiology of severe and fatal rattlesnake bites published in the American Association of Poison Control Centers' Annual Reports.

PubMed

Walter, Frank G; Stolz, Uwe; Shirazi, Farshad; McNally, Jude

2009-08-01

No study has focused on the nationwide epidemiology of severe and fatal rattlesnake bites during the last 25 years. We examined rates and temporal trends of severe and fatal rattlesnake bites across the United States. Our hypothesis was that nationwide annual rates of both severe and fatal outcomes from rattlesnake bites have remained unchanged over time. This study retrospectively analyzed all human rattlesnake bites published in the Annual Reports of the American Association of Poison Control Centers from 1983 through 2007. Annual rates of severe (major) and fatal rattlesnake bites were calculated using the annual number of major outcomes and fatalities as respective numerators and the total annual number of single rattlesnake bites (exposures) as denominators. Negative binomial and Poisson regressions were used to examine trends of severe and fatal rattlesnake bites over time. Annually, from 1985 to 2007, the incidence rate of major outcomes decreased by 2% per year (incidence rate ratio = 0.980; CI = 0.967-0.993), corresponding to an absolute annual rate decrease of two major outcomes per 1,000 bites per year. Annual rates of fatalities showed no statistically significant change from 1983 through 2007. This is the first study to examine rates and trends of published severe and fatal rattlesnake bites across the United States over the past 25 years. Annual rates of severe rattlesnake bites, derived from the published Annual Reports of the American Association of Poison Control Centers, have significantly decreased over time, whereas rates of fatal rattlesnake bites have remained unchanged.

The functional significance of morphological changes in the dentitions of early mammals.

PubMed

Conith, Andrew J; Imburgia, Michael J; Crosby, Alfred J; Dumont, Elizabeth R

2016-11-01

The Mesozoic marked a time of experimentation in the tooth morphology of early mammals. One particular experiment involved the movement of three points, or cusps, on the surface of a molar tooth from a line into a triangle. This transition is exemplified by two extinct insectivorous mammals, Morganucodon (cusps in a line) and Kuehneotherium (cusps in a triangle). Here we test whether this difference in cusp arrangement, alongside cusp heights and angles between cusps, is associated with differences in the ability of the teeth to fracture proxy-insect prey. We gathered measurements from molar teeth of both species and used them to create physical models. We then measured the force, time and energy at fracture and peak force, and the amount of damage inflicted by the models on hard and soft gels encased in a tough film that mimicked the material properties of insects. The Morganucodon model required less force and energy to fracture hard gels and reach peak force compared with Kuehneotherium Kuehneotherium required a similar time, force and energy to fracture soft gels but reduced the time, force and energy to reach peak force. More importantly, Kuehneotherium also inflicted more damage to both the hard and the soft gels. These results suggest that changes in dental morphology in some early mammals was driven primarily by selection for maximizing damage, and secondarily for maximizing biomechanical efficiency for a given food material property. © 2016 The Author(s).

Snake bite envenomation in Riyadh province of Saudi Arabia over the period (2005-2010).

PubMed

Al-Sadoon, Mohammed K

2015-03-01

The present investigation is a retrospective review of snake bites in Riyadh province over the period (2005-2010). A total of 1019 cases of bites admitted to the Ministry of Health medical centers in Riyadh province were analyzed on the basis of age, sex, time of bite and its site on the body, outcome of treatment, antiserum dose and type of snake. Bites occurred throughout the six years with the highest frequency in 2005 and least in 2006 where most of the bite cases were mild and all evolved to cure except four patients who died following the administration of antivenom during 24 h after snake bite. Most of the patients were males (81.7%) and the most attacked age was within the range of 11-30 years (51.5%). All the bites were mainly in the exposed limbs and the most frequently bitten anatomical regions were the lower limbs (427 cases, 41.9%), principally the feet. The study incriminates Cerastes cerastes gasperettii in most of the bites indicating it as the snake of medical importance in Riyadh province. Also, the study indicates low degree of threat in spite of high rate of snake bites as a result of the availability of the medical facilities and the antivenin use in medical centers in Riyadh province.

Repeated Amblyomma testudinarium tick bites are associated with increased galactose-α-1,3-galactose carbohydrate IgE antibody levels: A retrospective cohort study in a single institution.

PubMed

Hashizume, Hideo; Fujiyama, Toshiharu; Umayahara, Takatsune; Kageyama, Reiko; Walls, Andrew F; Satoh, Takahiro

2018-06-01

Alpha-gal syndrome is a hypersensitivity reaction to red meat mediated by IgE antibody specific to galactose-α-1,3-galactose carbohydrate (alpha-gal). Amblyomma tick bites are associated with this condition, but the pathophysiology is not understood. To clarify the mechanism of development of alpha-gal syndrome after tick bites. We compared alpha-gal antibody levels between patients with and without a history of tick bites and examined histologic stainings of tick bite lesions between patients with and without detectable alpha-gal IgE antibody. Patients who had ≥2 tick bites had higher levels of alpha-gal IgE antibody compared with those with only 1 tick bite or healthy individuals. On histologic investigation, greater numbers of basophils and eosinophils, but not mast cells, were observed infiltrating lesions of patients with ≥2 tick bites compared with those with 1 tick bite. Type 2 cytokine-producing T-cell infiltration was predominantly observed in such patients. The study was conducted at a single institution in Japan. In Amblyomma tick bite lesions, basophils; eosinophils; and type 2, cytokine-producing T cells infiltrate the skin and alpha-gal IgE antibodies are produced. These findings provide a potential mechanistic connection between Amblyomma bites and red meat hypersensitivity. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Illusion caused by vibration of muscle spindles reveals an involvement of muscle spindle inputs in regulating isometric contraction of masseter muscles.

PubMed

Tsukiboshi, Taisuke; Sato, Hajime; Tanaka, Yuto; Saito, Mitsuru; Toyoda, Hiroki; Morimoto, Toshifumi; Türker, Kemal Sitki; Maeda, Yoshinobu; Kang, Youngnam

2012-11-01

Spindle Ia afferents may be differentially involved in voluntary isometric contraction, depending on the pattern of synaptic connections in spindle reflex pathways. We investigated how isometric contraction of masseter muscles is regulated through the activity of their muscle spindles that contain the largest number of intrafusal fibers among skeletal muscle spindles by examining the effects of vibration of muscle spindles on the voluntary isometric contraction. Subjects were instructed to hold the jaw at resting position by counteracting ramp loads applied on lower molar teeth. In response to the increasing-ramp load, the root mean square (RMS) of masseter EMG activity almost linearly increased under no vibration, while displaying a steep linear increase followed by a slower increase under vibration. The regression line of the relationship between the load and RMS was significantly steeper under vibration than under no vibration, suggesting that the subjects overestimated the ramp load and excessively counteracted it as reflected in the emergence of bite pressure. In response to the decreasing-ramp load applied following the increasing one, the RMS hardly decreased under vibration unlike under no vibration, leading to a generation of bite pressure even after the offset of the negative-ramp load until the vibration was ceased. Thus the subjects overestimated the increasing rate of the load while underestimating the decreasing rate of the load, due to the vibration-induced illusion of jaw opening. These observations suggest that spindle Ia/II inputs play crucial roles both in estimating the load and in controlling the isometric contraction of masseter muscles in the jaw-closed position.

Comparison of short-term effects between face mask and skeletal anchorage therapy with intermaxillary elastics in patients with maxillary retrognathia.

PubMed

Ağlarcı, Cahide; Esenlik, Elçin; Fındık, Yavuz

2016-06-01

The aim of this study was to compare the short-term dental and skeletal effects of a face mask (FM) with those of skeletal anchorage (SA) therapy with intermaxillary elastics in prepubertal patients with skeletal Class III malocclusion. Fifty patients with skeletal Class III malocclusion and maxillary deficiency were divided into two groups. In the FM group, an FM was applied by a bite plate with a force of 400g for each side. In the SA group, mini-plates were placed between mandibular lateral incisors and canines, and mini-implants were inserted between maxillary second premolars and first molars. A bite plate was inserted into the upper arch, and Class III elastics were applied with a force of 200g between each mini-plate and mini-implant. Mean treatment durations were 0.52±0.09 years for FM and 0.76±0.09 years for SA. After the treatment, statistically significant increases in SNA°, ANB°, A-y, 1-NA, SnGoGn°, Co-A, Co-Gn, and A-Nperp, and reductions in SNB° and FH┴N-Pg were observed in both groups, and these changes were similar in both groups. In the FM group, 1-NB decreased significantly, and in the SA group, it increased significantly (P < 0.05). The undesired dentoalveolar effects of the FM treatment were eliminated with SA treatment, except with regard to lower incisor inclination. Favourable skeletal outcomes can be achieved by SA therapies, which could be an alternative to the extraoral appliances frequently applied to treat skeletal Class III patients with maxillary deficiency. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Malocclusion in Early Anatomically Modern Human: A Reflection on the Etiology of Modern Dental Misalignment

PubMed Central

Sarig, Rachel; Slon, Viviane; Abbas, Janan; May, Hila; Shpack, Nir; Vardimon, Alexander Dan; Hershkovitz, Israel

2013-01-01

Malocclusions are common in modern populations. Yet, as the study of occlusion requires an almost intact dentition in both the maxilla and mandible, searching for the ultimate cause of malocclusion is a challenge: relatively little ancient material is available for research on occlusal states. The Qafzeh 9 skull is unique, as its preserved dentition allowed us to investigate the presence and manifestations of malocclusion. The aim of this study was thus to examine the occlusal condition in the Qafzeh 9 specimen in light of modern knowledge regarding the etiology of malocclusion. We revealed a pathologic occlusion in the Qafzeh 9 skull that probably originated in the early developmental stage of the dentition, and was aggravated by forces applied by mastication. When arch continuity is interrupted due to misalignment of teeth as in this case, force transmission is not equal on both sides, causing intra-arch outcomes such as mesialization of the teeth, midline deviation, rotations and the aggravation of crowding. All are evident in the Qafzeh 9 skull: the midline deviates to the left; the incisors rotate mesio-buccally; the left segment is constricted; the left first molar is buccally positioned and the left premolars palatally tilted. The inter-arch evaluation revealed anterior cross bite with functional shift that might affect force transmission and bite force. In conclusion, the findings of the current study suggest that malocclusion of developmental origin was already present in early anatomically modern humans (AMH) (the present case being the oldest known case, dated to ca. 100,000 years); that there is no basis to the notion that early AMH had a better adjustment between teeth and jaw size; and that jaw-teeth size discrepancy could be found in prehistoric populations and is not a recent phenomenon. PMID:24278319

A comparative study between xerographic, computer-assisted overlay generation and animated-superimposition methods in bite mark analyses.

PubMed

Tai, Meng Wei; Chong, Zhen Feng; Asif, Muhammad Khan; Rahmat, Rabiah A; Nambiar, Phrabhakaran

2016-09-01

This study was to compare the suitability and precision of xerographic and computer-assisted methods for bite mark investigations. Eleven subjects were asked to bite on their forearm and the bite marks were photographically recorded. Alginate impressions of the subjects' dentition were taken and their casts were made using dental stone. The overlays generated by xerographic method were obtained by photocopying the subjects' casts and the incisal edge outlines were then transferred on a transparent sheet. The bite mark images were imported into Adobe Photoshop® software and printed to life-size. The bite mark analyses using xerographically generated overlays were done by comparing an overlay to the corresponding printed bite mark images manually. In computer-assisted method, the subjects' casts were scanned into Adobe Photoshop®. The bite mark analyses using computer-assisted overlay generation were done by matching an overlay and the corresponding bite mark images digitally using Adobe Photoshop®. Another comparison method was superimposing the cast images with corresponding bite mark images employing the Adobe Photoshop® CS6 and GIF-Animator©. A score with a range of 0-3 was given during analysis to each precision-determining criterion and the score was increased with better matching. The Kruskal Wallis H test showed significant difference between the three sets of data (H=18.761, p<0.05). In conclusion, bite mark analysis using the computer-assisted animated-superimposition method was the most accurate, followed by the computer-assisted overlay generation and lastly the xerographic method. The superior precision contributed by digital method is discernible despite the human skin being a poor recording medium of bite marks. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci.

PubMed

Huber, Daniel R; Eason, Thomas G; Hueter, Robert E; Motta, Philip J

2005-09-01

Three-dimensional static equilibrium analysis of the forces generated by the jaw musculature of the horn shark Heterodontus francisci was used to theoretically estimate the maximum force distributions and loadings on its jaws and suspensorium during biting. Theoretical maximum bite force was then compared with bite forces measured (1) voluntarily in situ, (2) in restrained animals and (3) during electrical stimulation of the jaw adductor musculature of anesthetized sharks. Maximum theoretical bite force ranged from 128 N at the anteriormost cuspidate teeth to 338 N at the posteriormost molariform teeth. The hyomandibula, which connects the posterior margin of the jaws to the base of the chondrocranium, is loaded in tension during biting. Conversely, the ethmoidal articulation between the palatal region of the upper jaw and the chondrocranium is loaded in compression, even during upper jaw protrusion, because H. francisci's upper jaw does not disarticulate from the chondrocranium during prey capture. Maximum in situ bite force averaged 95 N for free-swimming H. francisci, with a maximum of 133 N. Time to maximum force averaged 322 ms and was significantly longer than time away from maximum force (212 ms). Bite force measurements from restrained individuals (187 N) were significantly greater than those from free-swimming individuals (95 N) but were equivalent to those from both theoretical (128 N) and electrically stimulated measurements (132 N). The mean mass-specific bite of H. francisci was greater than that of many other vertebrates and second highest of the cartilaginous fishes that have been studied. Measuring bite force on restrained sharks appears to be the best indicator of maximum bite force. The large bite forces and robust molariform dentition of H. francisci correspond to its consumption of hard prey.

Fracture Strength of Three-Unit Implant Supported Fixed Partial Dentures with Excessive Crown Height Fabricated from Different Materials.

PubMed

Nazari, Vahideh; Ghodsi, Safoura; Alikhasi, Marzieh; Sahebi, Majid; Shamshiri, Ahmad Reza

2016-11-01

Fracture strength is an important factor influencing the clinical long-term success of implant-supported prostheses especially in high stress situations like excessive crown height space (CHS). The purpose of this study was to compare the fracture strength of implant-supported fixed partial dentures (FPDs) with excessive crown height, fabricated from three different materials. Two implants with corresponding abutments were mounted in a metal model that simulated mandibular second premolar and second molar. Thirty 3-unit frameworks with supportive anatomical design were fabricated using zirconia, nickel-chromium alloy (Ni-Cr), and polyetheretherketone (PEEK) (n=10). After veneering, the CHS was equal to 15mm. Then; samples were axially loaded on the center of pontics until fracture in a universal testing machine at a crosshead speed of 0.5 mm/minute. The failure load data were analyzed by one-way ANOVA and Games-Howell tests at significance level of 0.05. The mean failure loads for zirconia, Ni-Cr and PEEK restorations were 2086±362N, 5591±1200N and 1430±262N, respectively. There were significant differences in the mean failure loads of the three groups (P<0.001). The fracture modes in zirconia, metal ceramic and PEEK restorations were cohesive, mixed and adhesive type, respectively. According to the findings of this study, all implant supported three-unit FPDs fabricated of zirconia, metal ceramic and PEEK materials are capable to withstand bite force (even para-functions) in the molar region with excessive CHS.

Proximate determinants of bite force in Anolis lizards.

PubMed

Wittorski, Antoine; Losos, Jonathan B; Herrel, Anthony

2016-01-01

Performance measures associated with the vertebrate jaw system may provide important insights into vertebrate ecology and evolution because of their importance in many ecologically relevant tasks. Previous studies have shown that in many taxa, evolution toward higher bite force has gone hand in hand with the evolution of larger body size. However, independent of differences in overall body size, bite force may vary depending on head size and shape as well. Moreover, the underlying musculature may also drive variation in bite force. Here, we investigate the proximate determinants of bite force in lizards of the genus Anolis. We dissected the jaw muscles and quantified muscle mass, fibre length, and cross-sectional area. Data were analysed for both sexes independently given the sexual dimorphism detected in the dataset. Our results show that the traits that explain bite force are similar in both males and females with overall body size and muscle mass being the principal determinants. Among the different muscles examined, the adductor externus and the pseudotemporalis groups were the best determinants of bite force. However, models run for males predicted the variation in bite force better than models for females, suggesting that selection on morphology improving bite force may be stronger in males. © 2015 Anatomical Society.

Occupational Snake Bites: a Prospective Case Series of Patients Reported to the ToxIC North American Snakebite Registry.

PubMed

Spyres, Meghan B; Ruha, Anne-Michelle; Seifert, Steven; Onisko, Nancy; Padilla-Jones, Angela; Smith, Eric Anthony

2016-12-01

In the developing world, occupation has been identified as a risk factor for snake bite. Such an association has not been described in the USA. The objective of this study was to describe the epidemiology and clinical manifestations of occupational snake bite in patients reported to the ToxIC North American Snakebite Registry (NASBR). This was a prospective case series of patients reported to the ToxIC NASBR between January 1, 2014 and November 5, 2015. Variables collected included snake species, patient demographics, date and location of exposure, occupation, bite location, clinical manifestations, and management. Of 180 adult snake bites reported, 25 (13.9 %; 95 % CI 9.2-19.8 %) were occupational in nature. Rattlesnake envenomations were common (80 %). Most snake bites (96 %) occurred in men. Occupations most associated with snake bite were landscaping (28 %) and working directly with snakes (24 %). Fifty-six percent of bites occurred in an outdoor work environment. Seventy-six percent of envenomations were to the upper extremities. Intentional interaction occurred in 40 % of cases, all of which sustained finger envenomations. No cases presented with apparent acute ethanol intoxication. The majority of occupational snake bites occurred in men working outdoors and were unintentional injuries. Bites involving the upper extremity tended to result from intentional interactions. Acute ethanol intoxication did not appear to be involved with occupational envenomations.

Snake bite envenomation in Riyadh province of Saudi Arabia over the period (2005–2010)

PubMed Central

Al-Sadoon, Mohammed K.

2014-01-01

The present investigation is a retrospective review of snake bites in Riyadh province over the period (2005–2010). A total of 1019 cases of bites admitted to the Ministry of Health medical centers in Riyadh province were analyzed on the basis of age, sex, time of bite and its site on the body, outcome of treatment, antiserum dose and type of snake. Bites occurred throughout the six years with the highest frequency in 2005 and least in 2006 where most of the bite cases were mild and all evolved to cure except four patients who died following the administration of antivenom during 24 h after snake bite. Most of the patients were males (81.7%) and the most attacked age was within the range of 11–30 years (51.5%). All the bites were mainly in the exposed limbs and the most frequently bitten anatomical regions were the lower limbs (427 cases, 41.9%), principally the feet. The study incriminates Cerastes cerastes gasperettii in most of the bites indicating it as the snake of medical importance in Riyadh province. Also, the study indicates low degree of threat in spite of high rate of snake bites as a result of the availability of the medical facilities and the antivenin use in medical centers in Riyadh province. PMID:25737653

Validity of the Bite Counter device in a controlled laboratory setting.

PubMed

Desendorf, Jenna; Bassett, David R; Raynor, Hollie A; Coe, Dawn P

2014-08-01

Body-borne sensors may be useful in assessing eating behaviors and have the potential to overcome some of the limitations of self-report instruments. The Bite Counter is a new commercial device, worn on the wrist that purports to track the number of bites taken per day. It contains a tri-axial accelerometer that detects an upward, arcing motion from the table to the mouth, known as a wrist roll. To examine the validity of the Bite Counter device for measuring bites in individuals while consuming various foods and beverages. 15 adults (23-58 years old) wore the device on the wrist of their dominant hand. They were presented with a meal consisting of foods/beverages, each consumed with different utensils: meat (knife and fork), side items (fork), soup (spoon), pizza (hands), can of soda (hands), and a smoothie (straw). Each food or drink was consumed by itself, in consecutive order. A researcher observed them through a one-way mirror and counted the number of bites taken. The percentage of actual bites taken varied as follows: Meat (127%), side items (82.6%), soup (60.2%), pizza (87.3%), soda (81.7%), and smoothie (57.7%). The overall mean was 81.2% of bites taken. The results indicate that the Bite Counter holds promise for being able to count the number of hand-to-mouth movements. In general, it underestimated hand-to-mouth movements, but some types of hand movements caused overestimation of bites. Future studies should be undertaken to improve the sensitivity and specificity of the Bite Counter device. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of the Elastic Properties of Thirteen Silicone Interocclusal Recording Materials

PubMed Central

Zietek, Marek

2016-01-01

Background. Addition silicones are popular as dental impression materials and are used in bite registration procedures. Objective. This study aimed to compare the postsetting elasticities and other mechanical properties of thirteen addition silicone interocclusal recording materials. Materials and Methods. The following materials were investigated: Colorbite D, Futar D, Genie Bite, Jet Blue Bite fast, Memoreg 2, O-Bite, Occlufast Rock, Omni-Bite Plus, Regidur i, Registrado X-tra, Regofix transparent, StoneBite, and Variotime Bite. Thirty specimens of each material were tested. The elasticities and strengths of the materials were measured with a universal testing machine, and computer software was used to determine the E-moduli, ultimate tensile strengths, and ultimate elongations of the specimens. Results. The results were subjected to statistical analysis using the Kruskal-Wallis test (p ≤ 0.05). The statistics revealed that the mean E-modulus values varied significantly across the materials (p = 0.000) and were highest for the StoneBite and Registrado X-tra and lowest for the Regofix transparent. The ultimate tensile strengths were highest for the Regofix transparent and Registrado X-tra (p = 0.000) and lowest for the Jet Blue Bite fast and Memoreg 2 (p = 0.000). The elongation percentages at the point of breaking varied significantly across the materials (p = 0.000); the lowest value was observed for the StoneBite, whereas the Regofix transparent nearly doubled original length. Conclusions. The authors concluded that materials with the high E-moduli and great ultimate tensile strengths may be most useful clinically. Registrado X-tra and StoneBite best met these criteria. PMID:27747239

Consumer perception of salt-reduced breads: Comparison of single and two-bites evaluation.

PubMed

Antúnez, Lucía; Giménez, Ana; Alcaire, Florencia; Vidal, Leticia; Ares, Gastón

2017-10-01

Salt-reduction in processed products has been proposed as a high-impact intervention for reducing the sodium intake at population level. A major limitation for this approach is its potential negative impact on the sensory characteristics of products. The current practice in sensory and consumer science involves single sip/bite evaluations, which may not properly reflect the sensory experience that occurs during product consumption. In this context, the aim of the present work was to compare single and two bite evaluations of consumer sensory and hedonic perception of salt-reduced breads. Five studies with a total of 499 consumers were carried out, in which overall-liking scores of five salt-reduced bread samples were collected after the first and the second bite evaluation. In one of the studies consumers also answered a CATA (check-all-that-apply) question after the first and the second bite. Neither bite nor the interaction between samples and bite had a significant effect on hedonic scores. However, when hedonic scores were analysed separately for each bite, the overall liking scores from the second bite evaluation better reflected differences among samples according to their salt content in two of the five studies. The sensory characterization of the samples did not largely vary between the first and the second bite. Results suggest that consumers' perception of salt reduced bread samples did not largely vary between a single and a two bites evaluation. Further research is warranted in this regard, in particular considering more complex products. Copyright © 2017 Elsevier Ltd. All rights reserved.

21 CFR 882.5070 - Bite block.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bite block. 882.5070 Section 882.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5070 Bite block. (a) Identification. A bite block...

21 CFR 882.5070 - Bite block.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Bite block. 882.5070 Section 882.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5070 Bite block. (a) Identification. A bite block...

Degradation of polychlorinated biphenyl mixtures in soil using phanerochaete chrysosporium in nutrient rich, non-ligninolytic conditions

DOEpatents

Yadav, Jagjit S.; Reddy, Chilekampalli A.; Quensen, John F.; Tiedje, James M.

2000-01-01

Substantial degradation of polychlorinated biphenyl (PCB) mixtures is carried out using the white rot fungus Phanerochaete chrysosporium, under nutrient, carbon and nitrogen source rich, non-ligninolytic conditions. The PCBs with various numbers of ortho, meta, and para chlorines were extensively degraded, indicating relative nonspecificity for the position of chlorine substitutions on the biphenyl ring. Maximal degradation of PCBs in a mixture was observed in malt extract medium (18.4% on a molar basis), in which most of the individual PCBs were degraded.

Synthesis of Sulfonated burdock fructooligosaccharide (BFO)

NASA Astrophysics Data System (ADS)

Zhang, Haiguang; Chen, Kaoshan; Zhang, Pengying; Zhang, Xian; Wang, Zhe; Xue, Jingwen

2017-12-01

Burdock Fructooligosaccharide (BFO) were sulfated using SO3-Py complex. The maximal degree of sulfonation (DSsulf) was 1.56, which were obtained by varying reaction factor such molar ratio of SO3-Py to fructofuranans unit (FU). The FT-IR, 1H NMR and 13C NMR spectra showed the introduction of sulfate group, and the reaction occurred at C-6, C-4 and C-3 in the fructofuranans unit of BFO. The molecular weight estimated by HPGPC were 6104.7-11003.3 g/mol for S-BFO (DS sulf=1.2).

Streptococcus oralis cerebral abscess following monkey bite in a 2-month-old infant.

PubMed

Thiagarajan, Srinivasan; Krishnamurthy, Sriram; Raghavan, Renitha; Mahadevan, Subramanian; Madhugiri, Venkatesh S; Sistla, Sujatha

2016-05-01

Although cerebral abscesses caused by animal bites have been reported, they are extremely rare in infants and have not been described following monkey bite. A 55-day-old male infant presented with a multi-loculated Streptococcus oralis cerebral abscess following a monkey bite on the scalp. There was a clinical response to antibiotic therapy and repeated surgical aspiration followed by a ventriculoperitoneal shunt. This is the first report of a patient with a brain abscess following a monkey bite.

Verified spider bites in Oregon (USA) with the intent to assess hobo spider venom toxicity.

PubMed

McKeown, Nathanael; Vetter, Richard S; Hendrickson, Robert G

2014-06-01

This study compiled 33 verified spider bites from the state of Oregon (USA). The initial goal was to amass a series of bites by the hobo spider to assess whether it possesses toxic venom, a supposition which is currently in a contested state. None of the 33 bites from several spider species developed significant medical symptoms nor did dermonecrosis occur. The most common biters were the yellow sac spider, Cheiracanthium mildei (N = 10) and orb-weavers of the genus Araneus (N = 6). There were 10 bites from three genera of funnel web spiders of the family Agelenidae including one hobo spider bite and one from the congeneric giant house spider which is readily confused as a hobo spider. The hobo spider bite resulted in pain, redness, twitching in the calf muscle and resolved in 12 h. Also generated from this study were possibly the first records of bites from spiders of the genera Callobius (Amaurobiidae) and Antrodiaetus (Antrodiaetidae), both with minor manifestations. Published by Elsevier Ltd.

A verified spider bite and a review of the literature confirm Indian ornamental tree spiders (Poecilotheria species) as underestimated theraphosids of medical importance.

PubMed

Fuchs, Joan; von Dechend, Margot; Mordasini, Raffaella; Ceschi, Alessandro; Nentwig, Wolfgang

2014-01-01

Literature on bird spider or tarantula bites (Theraphosidae) is rare. This is astonishing as they are coveted pets and interaction with their keepers (feeding, cleaning the terrarium or taking them out to hold) might increase the possibility for bites. Yet, this seems to be a rare event and might be why most theraphosids are considered to be harmless, even though the urticating hairs of many American species can cause disagreeable allergic reactions. We are describing a case of a verified bite by an Indian ornamental tree spider (Poecilotheria regalis), where the patient developed severe, long lasting muscle cramps several hours after the bite. We present a comprehensive review of the literature on bites of these beautiful spiders and conclude that a delayed onset of severe muscle cramps, lasting for days, is characteristic for Poecilotheria bites. We discuss Poecilotheria species as an exception from the general assumption that theraphosid bites are harmless to humans. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of cetirizine, ebastine and loratadine in the treatment of immediate mosquito-bite allergy.

PubMed

Karppinen, A; Kautiainen, H; Petman, L; Burri, P; Reunala, T

2002-06-01

People frequently experience whealing and delayed papules from mosquito bites. Whealing is mediated by antisaliva immunoglobulin (Ig)E antibodies and histamine. Cetirizine, ebastine and loratadine have earlier shown effects on mosquito-bite reactions but no comparative studies exist. A double-blind, placebo-controlled, cross-over study was performed with cetirizine 10 mg, ebastine 10 mg and loratadine 10 mg in 29 mosquito-bite-sensitive adults exposed to Aedes aegypti mosquito-bites. The size of the bite lesion and the intensity of pruritus (visual analog scale) were measured at 15 min and 2, 6 and 24 h. Cetirizine and ebastine, but not loratadine, decreased significantly the size of whealing (P < 0.01) and accompanying pruritus (P < 0.001) compared to placebo. Cetirizine was most effective on pruritus but caused more often sedation than ebastine or loratadine. The delayed bite symptoms remained too faint for any statistical comparison. This comparative study in mosquito-bite-sensitive adults shows that cetirizine and ebastine decrease significantly whealing and accompanying pruritus, and that cetirizine seems to be the most effective against pruritus.

Is extreme bite performance associated with extreme morphologies in sharks?

PubMed

Huber, Daniel R; Claes, Julien M; Mallefet, Jérôme; Herrel, Anthony

2009-01-01

As top predators in many oceanic communities, sharks are known to eat large prey and are supposedly able to generate high bite forces. This notion has, however, largely gone untested due to the experimental intractability of these animals. For those species that have been investigated, it remains unclear whether their high bite forces are simply a consequence of their large body size or the result of diet-related adaptation. As aquatic poikilotherms, sharks can grow very large, making them ideal subjects with which to investigate the effects of body size on bite force. Relative bite-force capacity is often associated with changes in head shape because taller or wider heads can, for example, accommodate larger jaw muscles. Constraints on bite force in general may also be released by changes in tooth shape. For example, more pointed teeth may allow a predator to penetrate prey more effectively than blunt, pavementlike teeth. Our analyses show that large sharks do not bite hard for their body size, but they generally have larger heads. Head width is the best predictor of bite force across the species included in our study as indicated by a multiple regression model. Contrary to our predictions, sharks with relatively high bite forces for their body size also have relatively more pointed teeth at the front of the tooth row. Moreover, species including hard prey in their diet are characterized by high bite forces and narrow and pointed teeth at the jaw symphysis.

Bone-breaking bite force of Basilosaurus isis (Mammalia, Cetacea) from the late Eocene of Egypt estimated by finite element analysis.

PubMed

Snively, Eric; Fahlke, Julia M; Welsh, Robert C

2015-01-01

Bite marks suggest that the late Eocence archaeocete whale Basilosaurus isis (Birket Qarun Formation, Egypt) fed upon juveniles of the contemporary basilosaurid Dorudon atrox. Finite element analysis (FEA) of a nearly complete adult cranium of B. isis enables estimates of its bite force and tests the animal's capabilities for crushing bone. Two loadcases reflect different biting scenarios: 1) an intitial closing phase, with all adductors active and a full condylar reaction force; and 2) a shearing phase, with the posterior temporalis active and minimized condylar force. The latter is considered probable when the jaws were nearly closed because the preserved jaws do not articulate as the molariform teeth come into occulusion. Reaction forces with all muscles active indicate that B. isis maintained relatively greater bite force anteriorly than seen in large crocodilians, and exerted a maximum bite force of at least 16,400 N at its upper P3. Under the shearing scenario with minimized condylar forces, tooth reaction forces could exceed 20,000 N despite lower magnitudes of muscle force. These bite forces at the teeth are consistent with bone indentations on Dorudon crania, reatract-and-shear hypotheses of Basilosaurus bite function, and seizure of prey by anterior teeth as proposed for other archaeocetes. The whale's bite forces match those estimated for pliosaurus when skull lengths are equalized, suggesting similar tradeoffs of bite function and hydrodynamics. Reaction forces in B. isis were lower than maxima estimated for large crocodylians and carnivorous dinosaurs. However, comparison of force estimates from FEA and regression data indicate that B. isis exerted the largest bite forces yet estimated for any mammal, and greater force than expected from its skull width. Cephalic feeding biomechanics of Basilosaurus isis are thus consistent with habitual predation.

Open bite in prematurely born children.

PubMed

Harila, V; Heikkinen, T; Grön, M; Alvesalo, L

2007-01-01

The aims of this study were to: examine the expression of open bite in prematurely born children and discuss the etiological factors that may lead to bite it. The subjects were 328 prematurely born (<37 gestational weeks) Caucasoid and African American children and 1,804 full-term control children, who participated in the cross-sectional study of the Collaborative Perinatal Project in the 1960s and 1970s. Dental documents, including casts and photographs, were taken once at the age of 6-12 years in the mixed dentition. The occlusion was recorded by examining and measuring the hard stone casts. Vertical open bite was recorded only for full erupted teeth. The statistical method used was chi-square analysis. Significant differences in the incidence of anterior open bite (from left to right canine) was found between the preterm and control groups and between gender and ethnic groups. The prevalence of anterior open bite was nearly 9% in the preterm group and almost 7% in the control group. African Americans (9%) had a significantly greater incidence of open bite than Caucasians (3%; P<.0001). Generally, girls had a greater incidence of open bite than boys (8% vs 6%; P<.11). When the study groups were divided by prematurity, gender, and ethnic group, the prevalence of open bite was increased--especially in preterm African American boys compared to controls (11% vs 8%). The results show differences in the development of anterior open bite between ethnic and gender groups. Premature birth may also influence dental occlusal development. Of importance are the patient's: general health condition; respiratory infections; inadequate nasal- and mouth-breathing; oral habits; and other medical problems. Preterm children may be relatively more predisposed to etiological factors for the development of anterior open bite.

The examination and identification of bite marks in foods using 3D scanning and 3D comparison methods.

PubMed

Naether, Silvio; Buck, Ursula; Campana, Lorenzo; Breitbeck, Robert; Thali, Michael

2012-01-01

Bite mark analysis offers the opportunity to identify the biter based on the individual characteristics of the dentitions. Normally, the main focus is on analysing bite mark injuries on human bodies, but also, bite marks in food may play an important role in the forensic investigation of a crime. This study presents a comparison of simulated bite marks in different kinds of food with the dentitions of the presumed biter. Bite marks were produced by six adults in slices of buttered bread, apples, different kinds of Swiss chocolate and Swiss cheese. The time-lapse influence of the bite mark in food, under room temperature conditions, was also examined. For the documentation of the bite marks and the dentitions of the biters, 3D optical surface scanning technology was used. The comparison was performed using two different software packages: the ATOS modelling and analysing software and the 3D studio max animation software. The ATOS software enables an automatic computation of the deviation between the two meshes. In the present study, the bite marks and the dentitions were compared, as well as the meshes of each bite mark which were recorded in the different stages of time lapse. In the 3D studio max software, the act of biting was animated to compare the dentitions with the bite mark. The examined food recorded the individual characteristics of the dentitions very well. In all cases, the biter could be identified, and the dentitions of the other presumed biters could be excluded. The influence of the time lapse on the food depends on the kind of food and is shown on the diagrams. However, the identification of the biter could still be performed after a period of time, based on the recorded individual characteristics of the dentitions.

Less is More: A Comparison of Antibody-Gold Nanoparticle Conjugates of Different Ratios.

PubMed

Byzova, Nadezhda A; Safenkova, Irina V; Slutskaya, Elvira S; Zherdev, Anatoly V; Dzantiev, Boris B

2017-11-15

This comprehensive study is related to gold nanoparticles (GNPs) conjugated with antibodies. The goal of the study is to determine the minimal concentration of antibodies for conjugate synthesis when the conjugates have high antigen-capturing activity. Two systems were studied: gold nanoparticles conjugated with monoclonal antibodies (mAb-GNP) specific to Helicobacter pylori and gold nanoparticles conjugated with polyclonal antibodies (pAb-GNP) specific to mouse immunoglobulins. Several conjugates were synthesized with different GNP-to-antibody molar ratios (from 1:1 to 1:245) through nondirectional and noncovalent immobilization on a surface of GNPs with a diameter of 25.3 ± 4.6 nm. The maximal antigen-capturing activities and equilibrium constants of the conjugates correlate with the formation of a constant hydrodynamic radius of the conjugates for mAb-GNP (GNP to antibody molar ratio 1:58) and with the stabilizing concentration by flocculation curves for pAb-GNP (GNP to antibody molar ratio 1:116). The application of the conjugates to the lateral flow immunoassay shows that the antibody concentrations used for the conjugation can be reduced (below the stabilizing concentration) without losing activity for the mAb-GNP conjugates. The findings highlight that the optimal concentration of antibodies immobilized on the surface of GNPs is not always equal to the stabilizing concentration determined by the flocculation curve.

Bite Force Recording Devices - A Review

PubMed Central

Kumathalli, Kanteshwari Iranagouda; Jain, Vinay; Kumar, Rajesh

2017-01-01

In dental research, bite force serves as a valuable parameter to evaluate the efficacy of masticatory system. A variety of devices with different design and working principle have been used to record bite force, but no single device is capable to record all the required forces. One may find it difficult to choose a device that will fulfil the purpose of recording bite force for research. So, the present review aims to report and compare the wide range of devices and will help in describing their uses for recording bite force. PMID:29207848

Polymicrobial tenosynovitis with Pasteurella multocida and other Gram negative bacilli after a Siberian tiger bite

PubMed Central

Isotalo, P; Edgar, D; Toye, B

2000-01-01

Mammalian bites present a considerable clinical problem because they are often associated with bacterial infections. Pasteurella multocida is a microorganism that commonly infects both canine and small feline bites. Zoonotic infections developing after large feline bites have been recognised, although their reports are limited. We describe a 35 year old man who was bitten by a Siberian tiger and who developed infectious tenosynovitis secondary to P multocida, Bergeyella (Weeksella) zoohelcum, and Gram negative bacteria most like CDC group EF-4b and comamonas species. The latter three bacteria have not been isolated previously from large feline bite wounds. Key Words: animal bite • zoonotic infection • Pasteurella multocida • Bergeyella zoohelcum PMID:11127273

[Mammal bite management].

PubMed

Contreras-Marín, Misael; Sandoval-Rodríguez, Jorge Issac; García-Ramírez, Raúl; Morales-Yépez, Héctor Adolfo

Animal bites are a major public health problem, it is estimated that 2% of the population is bitten each year. Most bites are by dogs and the risk factors include young children, men, certain breeds of dogs and untrained dogs. The risk of infection after bites differs between animal species and depends on the animal teeth and oral flora. Animal bites are still a major cause of morbidity in patients of all ages and have caused several preventable childhood deaths. These wounds often become infected. If the wound requires it, early surgical evaluation must be performed. The use of antibiotics is only recommended for high risk bite wounds. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

Nonhealing Wounds Caused by Brown Spider Bites: Application of Hyperbaric Oxygen Therapy.

PubMed

Hadanny, Amir; Fishlev, Gregory; Bechor, Yair; Meir, Oshra; Efrati, Shai

2016-12-01

Bites by Loxosceles spiders (also known as recluse spiders or brown spiders) can cause necrotic ulcerations of various sizes and dimensions. The current standard of care for brown spider bites includes analgesics, ice, compression, elevation, antihistamines, and surgical debridement. Hyperbaric oxygen therapy (HBOT) in the treatment of brown spider bites has been administered in the early stage of ulceration, or 2 to 6 days after the bite. Unfortunately, the diagnosis of spider bite-related ulcers is often delayed and weeks or months may elapse before HBOT is considered. To evaluate the effect of HBOT on nonhealing wounds caused by brown spider bites in the late, chronic, nonhealing stage. Analysis of 3 patients with brown spider-bite healing wounds treated at The Sagol Center for Hyperbaric Medicine and Research in Israel. Patients presented 2 to 3 months after failure of other therapies including topical dressings, antibiotics, and corticosteroids. All patients were treated with daily 2 ATA (atmospheres absolute) with 100% oxygen HBOT sessions. All 3 patients were previously healthy without any chronic disease. Their ages were 30, 42, and 73 years. They were treated once daily for 13, 17, and 31 sessions, respectively. The wounds of all 3 patients healed, and there was no need for additional surgical intervention. There were no significant adverse events in any of the patients. Microvascular injury related to brown spider bites may culminate in ischemic nonhealing wounds even in a relatively young, healthy population. Hyperbaric oxygen therapy should be considered as a valuable therapeutic tool even months after the bite.

Factors associated with anterior open bite in children with developmental disabilities.

PubMed

de Castilho, Lia Silva; Abreu, Mauro Henrique Nogueira Guimarães; Pires E Souza, Luiz Gustavo de Almeida; Romualdo, Leiliane Teresinha de Almeida; Souza E Silva, Maria Elisa; Resende, Vera Lúcia Silva

2018-01-01

To investigate factors associated with anterior open bite in individuals aged from 2 to 33 years with developmental disabilities. This is a cross-sectional study. A total of 271 dental records were examined. The anterior open bite analyzed was determined based on clinic exam. These variables were also analyzed: gender, age, education level of mother, International Code of Diseases (ICD), mouth breathing, use of anticonvulsant drugs, hyperkinesis, pacifier use, thumb sucking, seizure, and involuntary movements. For the purposes of analysis, the individuals were categorized as being with and without anterior open bite. Variables with a p-value of < 0.25 in the bivariate analysis were incorporated into the logistic regression models. Mouth breathers had a 2.60-fold (95% CI: 1.35-5.01) greater chance of exhibiting anterior open bite than nasal breathers. Pacifier users are more likely to have an anterior open bite (3.32-fold, 95% CI: 1.62-6.77). Individuals with reported involuntary movements had a 2.66-fold (95% CI: 1.26-5.63) greater chance of exhibiting anterior open bite. Users of anticonvulsants drugs had a 3.05 (95% CI: 1.57-5.92) greater chance of showing anterior open bite. Involuntary movements, mouth breathing, using anticonvulsant drugs, and using pacifier are factors associated with anterior open bite in patients with developmental disabilities. © 2017 Special Care Dentistry Association and Wiley Periodicals, Inc.

Cheek-biting disorder: another stereotypic movement disorder?

PubMed

Sarkhel, Sujit; Praharaj, Samir Kumar; Akhtar, Sayeed

2011-12-01

Recurrent cheek biting, a form of self-injurious behavior is a rare entity which presents mostly to dentists and dermatologists. We report a case of recurrent severe cheek biting in an adult male leading to mucosal ulceration. The stereotypic pattern of cheek biting and associated behavior bears striking resemblance to other impulse control disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

Measurement of bite force variables related to human discrimination of left-right hardness differences of silicone rubber samples placed between the incisors.

PubMed

Dan, Haruka; Azuma, Teruaki; Hayakawa, Fumiyo; Kohyama, Kaoru

2005-05-01

This study was designed to examine human subjects' ability to discriminate between spatially different bite pressures. We measured actual bite pressure distribution when subjects simultaneously bit two silicone rubber samples with different hardnesses using their right and left incisors. They were instructed to compare the hardness of these two rubber samples and indicate which was harder (right or left). The correct-answer rates were statistically significant at P < 0.05 for all pairs of different right and left silicone rubber hardnesses. Simultaneous bite measurements using a multiple-point sheet sensor demonstrated that the bite force, active pressure and maximum pressure point were greater for the harder silicone rubber sample. The difference between the left and right was statistically significant (P < 0.05) for all pairs with different silicone rubber hardnesses. We demonstrated for the first time that subjects could perceive and discriminate between spatially different bite pressures during a single bite with incisors. Differences of the bite force, pressure and the maximum pressure point between the right and left silicone samples should be sensory cues for spatial hardness discrimination.

Functional near-infrared spectroscopy study on primary motor and somatosensory cortex response to biting and finger clenching.

PubMed

Shibusawa, Mami; Takeda, Tomotaka; Nakajima, Kazunori; Jun, Handa; Sekiguchi, Shinichi; Ishigami, Keiichi; Sakatani, Kaoru

2010-01-01

The purpose of this study was to compare the influence of biting and finger clenching intensity on the concentration of oxygenated hemoglobin (OxyHb) in regional cerebral blood flow (rCBF) as an indicator of brain activity in the primary motor (MI) and somatosensory (SI) cortices. Functional near-infrared spectroscopy (fNIRS) was used in 8 healthy subjects. Subjects were required to do biting (bite) and finger clenching (fclench) at 20, 50 and 80% of maximum force. To minimize the effect of temporal muscle activity on the working side of the jaw, the fNIRS probes were positioned contralaterally, in the left temporal region. Activation of MI and SI cortices with bite and fclench was noted in all subjects, irrespective of the intensity of bite and fclench. A significant increase was observed in OxyHb in MI and SI between 20% and both 50 and 80% intensity. In MI cortex, OxyHb showed a significant increase between 80% and both 20 and 50% fclench intensity. The results suggest that intensity of bite and fclench influences activation levels in MI and SI. Further, an activation was more obvious with bite than fclench.

Comparative evaluation of light-trap catches, electric motor mosquito catches and human biting catches of Anopheles in the Three Gorges Reservoir.

PubMed

Duo-quan, Wang; Lin-hua, Tang; Zhen-cheng, Gu; Xiang, Zheng; Man-ni, Yang; Wei-kang, Jiang

2012-01-01

The mosquito sampling efficiency of light-trap catches and electric motor mosquito catches were compared with that of human biting catches in the Three Gorges Reservoir. There was consistency in the sampling efficiency between light-trap catches and human biting catches for Anopheles sinensis (r = 0.82, P<0.01) and light-trap catches were 1.52 (1.35-1.71) times that of human biting catches regardless of mosquito density (r = 0.33, P>0.01), while the correlation between electric motor mosquito catches and human biting catches was found to be not statistically significant (r = 0.43, P>0.01) and its sampling efficiency was below that of human biting catches. It is concluded that light-traps can be used as an alternative to human biting catches of Anopheles sinensis in the study area and is a promising tool for sampling malaria vector populations.

Comparative Evaluation of Light-Trap Catches, Electric Motor Mosquito Catches and Human Biting Catches of Anopheles in the Three Gorges Reservoir

PubMed Central

Duo-quan, Wang; Lin-hua, Tang; Zhen-cheng, Gu; Xiang, Zheng; Man-ni, Yang; Wei-kang, Jiang

2012-01-01

The mosquito sampling efficiency of light-trap catches and electric motor mosquito catches were compared with that of human biting catches in the Three Gorges Reservoir. There was consistency in the sampling efficiency between light-trap catches and human biting catches for Anopheles sinensis (r = 0.82, P<0.01) and light-trap catches were 1.52 (1.35–1.71) times that of human biting catches regardless of mosquito density (r = 0.33, P>0.01), while the correlation between electric motor mosquito catches and human biting catches was found to be not statistically significant (r = 0.43, P>0.01) and its sampling efficiency was below that of human biting catches. It is concluded that light-traps can be used as an alternative to human biting catches of Anopheles sinensis in the study area and is a promising tool for sampling malaria vector populations. PMID:22235256

The impact of snake bite on household economy in Bangladesh.

PubMed

Hasan, S M K; Basher, A; Molla, A A; Sultana, N K; Faiz, M A

2012-01-01

The present study aims to assess the different types of costs for treatment of snake bite patients, to quantify household economic impact and to understand the coping mechanisms required to cover the costs for snake bite patients in Bangladesh. The patients admitted to four tertiary level hospitals in Bangladesh were interviewed using structured questionnaires including health-care-related expenditures and the way in which the expenditures were covered. Of the snakes which bit the patients, 54.2% were non-venomous, 45.8% were venomous and 42.2% of the patients were given polyvalent antivenom. The total expenditure related to snake bite varies from US$4 (US$1 = Taka 72) to US$2294 with a mean of US$124 and the mean income loss was US$93. Expenditure for venomous snake bite was US$231, which is about seven times higher than non-venomous snake bite (US$34). The treatment imposes a major economic burden on affected families, especially in venomous snake bite cases.

Human bites (image)

MedlinePlus

Human bites present a high risk of infection. Besides the bacteria which can cause infection, there is ... the wound extends below the skin. Anytime a human bite has broken the skin, seek medical attention.

Antimicrobial Prophylaxis in Adults

PubMed Central

Enzler, Mark J.; Berbari, Elie; Osmon, Douglas R.

2011-01-01

Antimicrobial prophylaxis is commonly used by clinicians for the prevention of numerous infectious diseases, including herpes simplex infection, rheumatic fever, recurrent cellulitis, meningococcal disease, recurrent uncomplicated urinary tract infections in women, spontaneous bacterial peritonitis in patients with cirrhosis, influenza, infective endocarditis, pertussis, and acute necrotizing pancreatitis, as well as infections associated with open fractures, recent prosthetic joint placement, and bite wounds. Perioperative antimicrobial prophylaxis is recommended for various surgical procedures to prevent surgical site infections. Optimal antimicrobial agents for prophylaxis should be bactericidal, nontoxic, inexpensive, and active against the typical pathogens that can cause surgical site infection postoperatively. To maximize its effectiveness, intravenous perioperative prophylaxis should be administered within 30 to 60 minutes before the surgical incision. Antimicrobial prophylaxis should be of short duration to decrease toxicity and antimicrobial resistance and to reduce cost. PMID:21719623

How many people have been bitten by dogs? A cross-sectional survey of prevalence, incidence and factors associated with dog bites in a UK community.

PubMed

Westgarth, Carri; Brooke, Megan; Christley, Robert M

2018-04-01

Dog bite studies are typically based on hospital records and may be biased towards bites requiring significant medical treatment. This study investigated true dog bite prevalence and incidence at a community-level and victim-related risk factors, in order to inform policy and prevention. A cross-sectional study of a community of 1280 households in Cheshire, UK, surveyed 694 respondents in 385 households. Data included dog ownership and bite history, demographics, health and personality (Ten Item Personality Inventory (TIPI) brief measure). Multivariable logistic regression modelled risk factors for having ever been bitten by a dog, accounting for clustering of individuals within households. A quarter of participants (24.78%, 95% CI 21.72 to 28.13) reported having ever been bitten by a dog during their lifetime, with only a third of bites described requiring further medical treatment and 0.6% hospital admission. Incidence of dog bites was 18.7 (11.0-31.8) per 1000 population per year. Males were 1.81 times more likely to have been bitten in their lifetime than females (95% CI 1.20 to 2.72, P=0.005). Current owners of multiple dogs were 3.3 times more likely (95% CI 1.13 to 9.69, P=0.03) to report having been bitten than people not currently owning a dog. Regarding all bites described, most commonly people were bitten by a dog that they had never met before the incident (54.7%). Individuals scoring higher in emotional stability had a lower risk of having ever been bitten (OR=0.77 for 1 point change in scale between 1 and 7, 95% CI 0.66 to 0.9, P=0.001). This study suggests that the real burden of dog bites is considerably larger than those estimated from hospital records. Further, many bites do not require medical treatment and hospital-based bite data are not representative of bites within the wider population. Victim personality requires further investigation and potential consideration in the design of bite prevention schemes. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Funnel-web spider bite

MedlinePlus

... page: //medlineplus.gov/ency/article/002844.htm Funnel-web spider bite To use the sharing features on ... the effects of a bite from the funnel-web spider. Male funnel-web spiders are more poisonous ...

The Effect of Psychological State and Social Support on Nail-Biting in Adolescents: An Exploratory Study

ERIC Educational Resources Information Center

Sisman, Fatma Nevin; Tok, Ozlem; Ergun, Ayse

2017-01-01

Nail-biting is one of the most common behavioral problems in children. This study aimed to examine factors affecting nail-biting among adolescents and the effects of psychological state and social support on nail-biting. This cross-sectional study was conducted between January and May of 2014 in seven schools in Istanbul (N = 724). Data were…

The management of bite wounds in children--a retrospective analysis at a level I trauma centre.

PubMed

Jaindl, Manuela; Grünauer, Judith; Platzer, Patrick; Endler, Georg; Thallinger, Christiane; Leitgeb, Johannes; Kovar, Florian M

2012-12-01

Animal bite wounds are a significant problem, which have caused several preventable child deaths in clinical practice in the past. The majority of bite wounds is caused by dogs and cats, and also humans have to be considered to lead to those extreme complicated diagnosis in the paediatric patient population. Early estimation of infection risk, adequate antibiotic therapy and, if indicated, surgical treatment, are cornerstones of successful cures of bite wounds. However, antibiotic prophylaxis and wound management are discussed controversially in the current literature. In our study, we retrospectively investigated the bite source, infection risk and treatment options of paediatric bite wounds. A total of 1592 paediatric trauma patients were analysed over a period of 19 years in this retrospective study at a level I trauma centre, Department of Trauma Surgery, Medical University of Vienna, Austria. Data for this study were obtained from our electronic patient records and follow-up visits. In our database, all paediatric patients triaged to our major urban trauma centre have been entered retrospectively. During the 19-year study period, 1592 paediatric trauma patients met the inclusion criteria. The mean age was 7.7 years (range 0-18.9), 878 (55.2%) were males and 714 (44.8%) were females. In our study population, a total of 698 dog bites (43.8%), 694 human bites (43.6%), 138 other bites (8.7%) and 62 cat bites (3.9%) have been observed. A total of 171 wounds (10.7%) have been infected. Surgical intervention was done in 27 wounds (1.7%). Gender-related incidence in bite wounds for dog and cat could be detected. Second, our findings for originator of bite wounds reflect the findings in the published literature. Total infection rate reached 10.7%, primary antibiotic therapy was administered in 221 cases (13.9%) and secondary antibiotic therapy in 20 (1.3%) cases. Observed infection rate of punctured wounds and wounds greater than 3 cm was 3 times higher than for all other wounds. Our findings need to be proven in further prospective clinical trials. Copyright © 2012 Elsevier Ltd. All rights reserved.

Geographic Variation in Access to Dog-Bite Care in Pakistan and Risk of Dog-Bite Exposure in Karachi: Prospective Surveillance Using a Low-Cost Mobile Phone System

PubMed Central

Zaidi, Syed Mohammad Asad; Labrique, Alain B.; Khowaja, Saira; Lotia-Farrukh, Ismat; Irani, Julia; Salahuddin, Naseem; Khan, Aamir Javed

2013-01-01

Background Dog-bites and rabies are under-reported in developing countries such as Pakistan and there is a poor understanding of the disease burden. We prospectively collected data utilizing mobile phones for dog-bite and rabies surveillance across nine emergency rooms (ER) in Pakistan, recording patient health-seeking behaviors, access to care and analyzed spatial distribution of cases from Karachi. Methodology and Principal Findings A total of 6212 dog-bite cases were identified over two years starting in February 2009 with largest number reported from Karachi (59.7%), followed by Peshawar (13.1%) and Hyderabad (11.4%). Severity of dog-bites was assessed using the WHO classification. Forty percent of patients had Category I (least severe) bites, 28.1% had Category II bites and 31.9% had Category III (most severe bites). Patients visiting a large public hospital ER in Karachi were least likely to seek immediate healthcare at non-medical facilities (Odds Ratio = 0.20, 95% CI 0.17–0.23, p-value<0.01), and had shorter mean travel time to emergency rooms, adjusted for age and gender (32.78 min, 95% CI 31.82–33.78, p-value<0.01) than patients visiting hospitals in smaller cities. Spatial analysis of dog-bites in Karachi suggested clustering of cases (Moran's I = 0.02, p value<0.01), and increased risk of exposure in particular around Korangi and Malir that are adjacent to the city's largest abattoir in Landhi. The direct cost of operating the mHealth surveillance system was USD 7.15 per dog-bite case reported, or approximately USD 44,408 over two years. Conclusions Our findings suggest significant differences in access to care and health-seeking behaviors in Pakistan following dog-bites. The distribution of cases in Karachi was suggestive of clustering of cases that could guide targeted disease-control efforts in the city. Mobile phone technologies for health (mHealth) allowed for the operation of a national-level disease reporting and surveillance system at a low cost. PMID:24349590

Epidemiology, clinical features and risk factors for human rabies and animal bites during an outbreak of rabies in Maputo and Matola cities, Mozambique, 2014: Implications for public health interventions for rabies control.

PubMed

Salomão, Cristolde; Nacima, Amílcar; Cuamba, Lutero; Gujral, Lorna; Amiel, Olga; Baltazar, Cynthia; Cliff, Julie; Gudo, Eduardo Samo

2017-07-01

In Mozambique, the majority of rabies outbreaks are unreported and data on the epidemiological features of human rabies and animal bites are scarce. An outbreak of human rabies in adjacent Maputo and Matola cities in 2014 prompted us to investigate the epidemiology, clinical features and risk factors of human rabies and animal bites in the two cities. We reviewed cases of human rabies and animal bites from April to July 2014, and carried out a community investigation in July and August in the neighborhoods where cases of human rabies resided. This investigation included collection of clinical, demographic and epidemiological information and a case control study to investigate the risk factors associated with human rabies. Fourteen cases of human rabies were detected in Maputo (n = 10) and Matola (n = 3) cities and neighbouring Boane district (n = 1) between April and August 2014, all of whom had been admitted to hospital. All had a recent history of dog bite. Of the 14 rabid dogs, only one had been immunized. 819 cases of animal bites were registered, of which 64.6% (529/819) were from Maputo City. Dogs were responsible for 97.8% (801/819) of all animal bites, but only 27.0% (126/467) were immunized. Factors significantly associated with human rabies were: age <15 years (p = 0.05), bite by stray dog (p = 0.002), deep wound (p = 0.02), bite in the head (p = 0.001), bite by unimmunized dog (p = 0.01), no use of soap and water (p = 0.001), and no post-exposure prophylaxis (p = 0.01). Implementation of control measures for rabies is poor in Maputo and Matola cities, where cases of human rabies were strongly associated with bites by stray and unvaccinated dogs and irregular implementation of post-exposure measures.

California Sea Lion (Zalophus californianus) and Harbor Seal (Phoca vitulina richardii) Bites and Contact Abrasions in Open-Water Swimmers: A Series of 11 Cases.

PubMed

Nuckton, Thomas J; Simeone, Claire A; Phelps, Roger T

2015-12-01

To review cases of bites and contact abrasions in open-water swimmers from California sea lions (Zalophus californianus) and harbor seals (Phoca vitulina richardii). Open-water swimmers from a San Francisco swimming club were questioned about encounters with pinnipeds (seals and sea lions) that resulted in bites or contact abrasions. When possible, wounds were documented with photographs. Medical follow-up and treatment complications were also reviewed. From October 2011 to December 2014, 11 swimmers reported bites by a sea lion (n = 1), harbor seal (n = 7), or unidentified pinniped (n = 3). Ten of the encounters occurred in San Francisco Bay; 1 occurred in the Eld Inlet, in Puget Sound, near Olympia, WA. None of the swimmers were wearing wetsuits. All bites involved the lower extremities; skin was broken in 4 of 11 bites and antibiotics were prescribed in 3 cases. One swimmer, who was bitten by a harbor seal, also had claw scratches. A treatment failure occurred with amoxicillin/clavulanate in another swimmer who was bitten by an unidentified pinniped; the wound healed subsequently with doxycycline, suggesting an infection with Mycoplasma spp. There were no long-lasting consequences from any of the bites. The majority of cases occurred at low tide, and bumping of the swimmer by the animal before or after a bite was common, but no clear tide or attack pattern was identified. Bites and contact abrasions from sea lions and harbor seals are reported infrequently in open-water swimmers and typically involve the lower extremities. Because of the risk of Mycoplasma infection, treatment with a tetracycline is recommended in pinniped bites with signs of infection or serious trauma. Attempting to touch or pet sea lions or seals is inadvisable and prohibited by the Marine Mammal Protection Act. Swimmers should leave the water as soon as possible after a bite or encounter. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

An evaluation of rabies vaccination rates among canines and felines involved in biting incidents within the Wellington-Dufferin-Guelph Public Health Department.

PubMed

Bottoms, K; Trotz-Williams, L; Hutchison, S; MacLeod, J; Dixon, J; Berke, O; Poljak, Z

2014-11-01

The objectives of this study were to determine the rate of animal bite incidents occurring in the human population of a local health department, and to determine the proportion of these canines and felines that were not up to date on their rabies vaccination at the time the incident occurred. Data were obtained from animal bite incidents reported to Wellington-Dufferin-Guelph Public Health during 2010 and 2011. Descriptive statistics of 718 eligible reports revealed the average rate of animal biting was 1.55 bites per 1000 residents per year. Approximately 54% of these animals were vaccinated against rabies, 32% were not up to date with their rabies vaccination, and the remaining 14.5% were of unknown status. The unit of analysis was the municipality, and the four outcomes of interest were: (i) number of animal bite incidents per 1000 residents, (ii) number of dog bite incidents per 1000 residents, (iii) proportion of animals involved in bite incidents that were not up to date with their rabies vaccination, and (iv) proportion of dogs that were not up to date. Associations between the outcomes and selected demographic variables were investigated using regression analysis. The number of veterinary clinics per 10,000 residents, and whether the municipality was urban or rural were identified as significant predictors for the number of animal bites per 1000 residents, and the number of dog bites. There were no significant predictors for the proportion of unvaccinated animals or dogs. Spatial clustering and the location of spatial clusters were assessed using the empirical Bayes index and spatial scan test. This analysis identified five municipalities within the health department that have a high rate of biting incidents and a high proportion of animals that were not up to date on their rabies vaccination. Such municipalities are ideal for targeted educational campaigns regarding the importance of vaccination in pets. © 2014 Blackwell Verlag GmbH.

Bone-Breaking Bite Force of Basilosaurus isis (Mammalia, Cetacea) from the Late Eocene of Egypt Estimated by Finite Element Analysis

PubMed Central

Snively, Eric; Fahlke, Julia M.; Welsh, Robert C.

2015-01-01

Bite marks suggest that the late Eocence archaeocete whale Basilosaurus isis (Birket Qarun Formation, Egypt) fed upon juveniles of the contemporary basilosaurid Dorudon atrox. Finite element analysis (FEA) of a nearly complete adult cranium of B. isis enables estimates of its bite force and tests the animal’s capabilities for crushing bone. Two loadcases reflect different biting scenarios: 1) an intitial closing phase, with all adductors active and a full condylar reaction force; and 2) a shearing phase, with the posterior temporalis active and minimized condylar force. The latter is considered probable when the jaws were nearly closed because the preserved jaws do not articulate as the molariform teeth come into occulusion. Reaction forces with all muscles active indicate that B. isis maintained relatively greater bite force anteriorly than seen in large crocodilians, and exerted a maximum bite force of at least 16,400 N at its upper P3. Under the shearing scenario with minimized condylar forces, tooth reaction forces could exceed 20,000 N despite lower magnitudes of muscle force. These bite forces at the teeth are consistent with bone indentations on Dorudon crania, reatract-and-shear hypotheses of Basilosaurus bite function, and seizure of prey by anterior teeth as proposed for other archaeocetes. The whale’s bite forces match those estimated for pliosaurus when skull lengths are equalized, suggesting similar tradeoffs of bite function and hydrodynamics. Reaction forces in B. isis were lower than maxima estimated for large crocodylians and carnivorous dinosaurs. However, comparison of force estimates from FEA and regression data indicate that B. isis exerted the largest bite forces yet estimated for any mammal, and greater force than expected from its skull width. Cephalic feeding biomechanics of Basilosaurus isis are thus consistent with habitual predation. PMID:25714832

Epidemiology, clinical features and risk factors for human rabies and animal bites during an outbreak of rabies in Maputo and Matola cities, Mozambique, 2014: Implications for public health interventions for rabies control

PubMed Central

Salomão, Cristolde; Nacima, Amílcar; Cuamba, Lutero; Gujral, Lorna; Amiel, Olga; Baltazar, Cynthia; Cliff, Julie

2017-01-01

Background In Mozambique, the majority of rabies outbreaks are unreported and data on the epidemiological features of human rabies and animal bites are scarce. An outbreak of human rabies in adjacent Maputo and Matola cities in 2014 prompted us to investigate the epidemiology, clinical features and risk factors of human rabies and animal bites in the two cities. Methodology/Principal findings We reviewed cases of human rabies and animal bites from April to July 2014, and carried out a community investigation in July and August in the neighborhoods where cases of human rabies resided. This investigation included collection of clinical, demographic and epidemiological information and a case control study to investigate the risk factors associated with human rabies. Fourteen cases of human rabies were detected in Maputo (n = 10) and Matola (n = 3) cities and neighbouring Boane district (n = 1) between April and August 2014, all of whom had been admitted to hospital. All had a recent history of dog bite. Of the 14 rabid dogs, only one had been immunized. 819 cases of animal bites were registered, of which 64.6% (529/819) were from Maputo City. Dogs were responsible for 97.8% (801/819) of all animal bites, but only 27.0% (126/467) were immunized. Factors significantly associated with human rabies were: age <15 years (p = 0.05), bite by stray dog (p = 0.002), deep wound (p = 0.02), bite in the head (p = 0.001), bite by unimmunized dog (p = 0.01), no use of soap and water (p = 0.001), and no post-exposure prophylaxis (p = 0.01). Conclusions/Significance Implementation of control measures for rabies is poor in Maputo and Matola cities, where cases of human rabies were strongly associated with bites by stray and unvaccinated dogs and irregular implementation of post-exposure measures. PMID:28742094

Efficacy and effects of various anti-crib devices on behaviour and physiology of crib-biting horses.

PubMed

Albright, J D; Witte, T H; Rohrbach, B W; Reed, A; Houpt, K A

2016-11-01

Crib-biting is a common oral stereotypy. Although most treatments involve prevention, the efficacy of various anti-crib devices, including surgically implanted gingival rings, has thus far not been empirically tested. Demonstrate the effect that 2 anti-crib collars, muzzle and gingival rings have on crib-biting, other maintenance behaviours, and cortisol levels in established crib-biting horses. Randomised, crossover clinical trial. In Experiment I, 2 anti-crib collars and a muzzle were used on 8 established crib-biting horses; horses wore each of 3 devices for 7 days, with a 7-day device-free period between treatments. Horses were video recorded for 24 h at least 3 times each week prior to any device placement, and always the day after a device was removed. In Experiment II, gingival rings were used in 6 established crib-biting horses; horses were video recorded for 3 days prior to ring implantation and the day after surgery until the rings became ineffective. Plasma cortisol levels were assessed every day during Experiment II and on Days 1, 3 and 5 of each week during Experiment I. All devices significantly reduced crib-biting compared with control periods. There was no significant difference in crib-bite reduction amongst devices in Experiment I, or between pre-device periods and the first day the device was removed. The only increase in plasma cortisol occurred on the day of surgery in Experiment II. Common anti-crib devices are effective in reducing crib-biting and significant distress was not evident from our findings. We did not find a post inhibitory rebound effect. Surgical rings were successful only temporarily and implantation was probably painful to the horses. Because stereotypies involve suboptimal environmental conditions, efforts should be made to improve husbandry factors previously shown to contribute to crib-biting, and research into decreasing horses' motivation to crib-bite should continue. © 2015 EVJ Ltd.

Mandatory desexing of dogs: one step in the right direction to reduce the risk of dog bite? A systematic review.

PubMed

D'Onise, Katina; Hazel, Susan; Caraguel, Charles

2017-06-01

Preventing dog bites is an intractable problem given the complex dog bite injury environment. Desexing of dogs has the opportunity of creating a safer injury environment, given the potential links between desexing and behaviour change in dogs. A systematic review of the literature was conducted to examine the evidence for desexing of dogs to reduce dog bite risk within a population health paradigm. Medline and CAB Abstracts were searched for studies that reported data on the association of dog neuter status with the risk of dog bite. All definitions of dog bite were included and all empirical studies were included in the review, limited to those published in English. Quality appraisal and data extraction were based on the 2013 evidence-based practice and critical appraisal tool from the University of Auckland. Five out of six observational studies, from four study populations found evidence that intact dogs were associated with an increased risk of dog bite compared with desexed dogs. The effect sizes ranged across the studies and given the heterogeneity of the studies no single effect size on the association between desexing and dog bite risk could be estimated. There is consistent evidence that desexing dogs is associated with a reduced risk of dog bite, although the studies reflect association and may not be causal. Although recent publications have suggested desexing is associated with health and behavioural costs in some breeds, population level evidence supports desexed dogs having a longer lifespan, and being less likely to wander with the added benefit of reducing unwanted litters. Thus, mandatory desexing presents a possible opportunity for prevention of dog bites expanding dog bite prevention beyond an education-only approach. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Animal Bites of the Hand

MedlinePlus

... animal bite Find a hand surgeon near you. Videos Figures Figure 1: Finger infection from cat bite ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

Microbial Analysis of Bite Marks by Sequence Comparison of Streptococcal DNA

PubMed Central

Kennedy, Darnell M.; Stanton, Jo-Ann L.; García, José A.; Mason, Chris; Rand, Christy J.; Kieser, Jules A.; Tompkins, Geoffrey R.

2012-01-01

Bite mark injuries often feature in violent crimes. Conventional morphometric methods for the forensic analysis of bite marks involve elements of subjective interpretation that threaten the credibility of this field. Human DNA recovered from bite marks has the highest evidentiary value, however recovery can be compromised by salivary components. This study assessed the feasibility of matching bacterial DNA sequences amplified from experimental bite marks to those obtained from the teeth responsible, with the aim of evaluating the capability of three genomic regions of streptococcal DNA to discriminate between participant samples. Bite mark and teeth swabs were collected from 16 participants. Bacterial DNA was extracted to provide the template for PCR primers specific for streptococcal 16S ribosomal RNA (16S rRNA) gene, 16S–23S intergenic spacer (ITS) and RNA polymerase beta subunit (rpoB). High throughput sequencing (GS FLX 454), followed by stringent quality filtering, generated reads from bite marks for comparison to those generated from teeth samples. For all three regions, the greatest overlaps of identical reads were between bite mark samples and the corresponding teeth samples. The average proportions of reads identical between bite mark and corresponding teeth samples were 0.31, 0.41 and 0.31, and for non-corresponding samples were 0.11, 0.20 and 0.016, for 16S rRNA, ITS and rpoB, respectively. The probabilities of correctly distinguishing matching and non-matching teeth samples were 0.92 for ITS, 0.99 for 16S rRNA and 1.0 for rpoB. These findings strongly support the tenet that bacterial DNA amplified from bite marks and teeth can provide corroborating information in the identification of assailants. PMID:23284761

Diet, bite force and skull morphology in the generalist rodent morphotype.

PubMed

Maestri, R; Patterson, B D; Fornel, R; Monteiro, L R; de Freitas, T R O

2016-11-01

For many vertebrate species, bite force plays an important functional role. Ecological characteristics of a species' niche, such as diet, are often associated with bite force. Previous evidence suggests a biomechanical trade-off between rodents specialized for gnawing, which feed mainly on seeds, and those specialized for chewing, which feed mainly on green vegetation. We tested the hypothesis that gnawers are stronger biters than chewers. We estimated bite force and measured skull and mandible shape and size in 63 genera of a major rodent radiation (the myomorph sigmodontines). Analysis of the influence of diet on bite force and morphology was made in a comparative framework. We then used phylogenetic path analysis to uncover the most probable causal relationships linking diet and bite force. Both granivores (gnawers) and herbivores (chewers) have a similar high bite force, leading us to reject the initial hypothesis. Path analysis reveals that bite force is more likely influenced by diet than the reverse causality. The absence of a trade-off between herbivores and granivores may be associated with the generalist nature of the myomorph condition seen in sigmodontine rodents. Both gnawing and chewing sigmodontines exhibit similar, intermediate phenotypes, at least compared to extreme gnawers (squirrels) and chewers (chinchillas). Only insectivorous rodents appear to be moving towards a different direction in the shape space, through some notable changes in morphology. In terms of diet, natural selection alters bite force through changes in size and shape, indicating that organisms adjust their bite force in tandem with changes in food items. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Fight Bite Injuries: Aggressive Tendencies Associated with Smaller Second to Fourth Digit Ratio.

PubMed

Joyce, Cormac W; O' Regan, Andrew; Kelly, Jack L; O' Shaughnessy, Michael

2017-12-01

Fight bite injuries are typically sustained by young, combative males and are the direct consequence of an aggressive act. Second to fourth digit ratios (2D:4D) are dependent on prenatal androgen exposure and lower ratios have been shown to be linked to various psychological and physical traits, including aggression. The aim of this study was to examine the 2D:4D ratios in a cohort of patients with fight bite injuries and compare these to an age and gender-matched control group. The 2D:4D ratios were calculated using plain films of the hand from 133 patients (122 males, 11 females) with fight bite injuries. A further 133 radiographs were obtained from patients that did not have fight bite injuries and digit ratios were calculated in the same fashion. Statistical analysis was then carried out to compare the 2D:4D ratios between the different groups. The 2D:4D ratios for male fight bite patients was significantly smaller than the male control group (p < 0.05). No significant difference was observed between the female fight bite patients and the female control group (p > 0.05). Fight bite injuries are usually sustained as a result of aggression. 2D:4D ratios are reflect intrauterine androgen exposure and low ratios have been linked to aggressive tendencies. We have demonstrated that male patients who sustained fight bite injuries have a lower 2D:4D ratio then the general population, thereby suggesting that exposure to prenatal androgens can lead to aggressive tendencies in adulthood. This suggests that lower ratios may predict a predisposition to acts of aggression, and as such result in an increased likelihood of sustaining an injury such as a fight bite.

Fatal dog attacks, 1989-1994.

PubMed

Sacks, J J; Lockwood, R; Hornreich, J; Sattin, R W

1996-06-01

To update data on fatal dog bites and see if past trends have continued. To merge data from vital records, the Humane Society of the United States, and searches of electronic news files. United States. U.S. residents dying in the U.S. from 1989 through 1994 from dog bites. We identified 109 dog bite-related fatalities, of which 57% were less than 10 years of age. The death rate for neonates was two orders of magnitude higher than for adults and the rate for children one order of magnitude higher. Of classifiable deaths, 22% involved an unrestrained dog off the owner's property, 18% involved a restrained dog on the owner's property, and 59% involved an unrestrained dog on the owner's property. Eleven attacks involved a sleeping infant; 19 dogs involved in fatal attacks had a prior history of aggression; and 19 of 20 classifiable deaths involved an unneutered dog. Pit bulls, the most commonly reported breed, were involved in 24 deaths; the next most commonly reported breeds were rottweilers (16) and German shepherds (10). The dog bite problem should be reconceptualized as a largely preventable epidemic. Breed-specific approaches to the control of dog bites do not address the issue that many breeds are involved in the problem and that most of the factors contributing to dog bites are related to the level of responsibility exercised by dog owners. To prevent dog bite-related deaths and injuries, we recommend public education about responsible dog ownership and dog bite prevention, stronger animal control laws, better resources for enforcement of these laws, and better reporting of bites. Anticipatory guidance by pediatric health care providers should address dog bite prevention.

Why your housecat's trite little bite could cause you quite a fright: a study of domestic felines on the occurrence and antibiotic susceptibility of Pasteurella multocida.

PubMed

Freshwater, A

2008-10-01

Approximately four to five million animal bite wounds are reported in the USA each year. Domestic companion animals inflict the majority of these wounds. Although canine bites far outnumber feline bites, unlike the dog, the cat's bite is worse than its bark; 20-80% of all cat bites will become infected, compared with only 3-18% of dog bite wounds. Pasteurella multocida is the most commonly cultured bacterium from infected cat bite wounds. Anyone seeking medical attention for a cat-inflicted bite wound is given prophylactic/empiric penicillin or a derivative to prevent Pasteurella infection (provided they are not allergic to penicillins). In an effort to establish a carriage rate of P. multocida in the domestic feline, bacterial samples from the gingival margins of domestic northern Ohio cats (n=409) were cultured. Isolates were tested for antibiotic sensitivity as prophylactic/empiric use of penicillin and its derivatives could potentially give rise to antibiotic resistance in P. multocida. The high carriage rate (approximately 90%) of P. multocida observed was found to be independent of physiological and behavioural variables including age, breed, food type, gingival scale, lifestyle and sex. High antibiotic susceptibility percentages were observed for benzylpenicillin, amoxicillin-clavulanate, cefazolin, and azithromycin (100%, 100%, 98.37% and 94.02%, respectively) in P. multocida isolates. The high prevalence of P. multocida in the feline oral cavity indicates that prophylactic/empiric antibiotic therapy is still an appropriate response to cat bite wounds. Additionally, the susceptibility of P. multocida to penicillin and its derivatives indicates that they remain reliable choices for preventing and treating P. multocida infections.

An Algorithmic Approach to Operative Management of Complex Pediatric Dog Bites: 3-Year Review of a Level I Regional Referral Pediatric Trauma Hospital

PubMed Central

Shayesteh, Ali; Xu, Min Li

2017-01-01

Background: Incidence of dog bites continues to rise among the pediatric population and serves as a public health threat for the well-being of children. Plastic surgeons are at the forefront of initial management and eventual outcome of these devastating injuries. This study set out to determine the nature of dog bite injuries treated over a 3-year period at a large level 1 pediatric trauma center. Methods: A retrospective review of emergency room records of all pediatric patients (age, 0–18 years old) who sustained dog bites between January 2012 and December 2014 were gathered. All details about age of patient, location and severity of dog bites, type of dog breed, antibiotics given, and emergency versus operative treatment were recorded and analyzed. Results: One hundred eight patients aged 5 months to 18 years old were treated in the emergency department after suffering dog bite injuries during the study period. The highest incidence of dog bites occurred in preschool children. The mean age for patients who required operative repair was lower than the mean age for patients who underwent primary closure in the emergency department. The location of injury was most commonly isolated to the head/neck region. Of the 56 cases that had an identified dog breed, pit bulls accounted for 48.2% of the dog bites, and 47.8% of pit bull bites required intervention in the operating room. Conclusion: Children with large dog bite injuries require more immediate care in a level 1 pediatric trauma hospitals in order to optimize their hospitalization course and eventual outcome. PMID:29184724

Effect of occlusal splint therapy on maximum bite force in individuals with moderate to severe attrition of teeth.

PubMed

Jain, Veena; Mathur, Vijay Prakash; Abhishek, Kumar; Kothari, Mohit

2012-10-01

The purpose of the pilot study was to determine the effect of restoring lost occlusal vertical dimension (OVD) due to attrition on maximum bite force in humans. A total of 124 subjects in age range of 25-40 years, with moderate to severe attrition, having full complement of teeth were screened according to inclusion and exclusion criteria. After consent, occlusal vertical dimension was assessed by employing mechanical and physiological methods in the experimental group and a maxillary canine guided hard splint was fabricated for each subjects fulfilling inclusion criteria and with positive consent (78). Bite force in experimental group was measured before, immediately after delivery of splint and subsequently at an interval of four, eight, and twelve weeks. Due loss during follow up, only 50 subjects could be available for bite force recording till 12 weeks. Bite force of age, gender, height and weight matched controls with no signs of attrition was also measured for comparison. Bite force of the experimental group was found to be significantly less than the matched controls (P=0.000) initially. After delivery of splint, bite force values increased progressively till twelve weeks. However comparison of bite force values of experimental group with control group showed no significant difference at end of eight (P=0.008) and twelve weeks (P=0.162). It was concluded that maximum bite force increases with restoration of lost vertical using splint therapy. A time period of 8-12 weeks is required to restore the maximum bite force value approximately similar to matched controls. Copyright © 2012 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Necrotizing fasciitis due to Streptococcus mitis caused by accidental human bite.

PubMed

Bastug, Aliye; Kislak, Sumeyye; Mutlu, Nevzat Mehmet; Akcaboy, Zeynep Nur; Koksal, Asude; Sertcelik, Ahmet; Ünlü, Ramazan Erkin; Akinci, Esragul; Bodur, Hurrem

2016-01-31

Human bite wounds are more prone to infection than animal bites, which may cause necrotizing soft tissue infections such as myositis, fasciitis. Both aerobic and anaerobic microorganisms may be responsible, including Streptococcus spp., Staphylococcus aureus, Peptostreptococcus spp. Necrotizing fasciitis is characterized by serious tissue destruction and systemic toxicity with high morbidity and mortality. We report a patient with Streptococcus mitis associated necrotizing fasciitis on the upper extremity resulting from an accidental human bite, which caused nearly fatal infection. Prophylactic antibiotic treatment should be given after a human bite to prevent infection. If the infection signs and symptoms develop, rapid diagnosis, appropriate antibiotic and surgical therapy should be administered immediately. Streptococcus mitis is a viridans streptococcus, usually known as a relatively benign oral streptococcus. To our knowledge, this is the first necrotizing fasciitis case due to Streptococcus mitis after human bite.

[Adverse reactions to mosquito bites in scholars from Monterrey, Nuevo Leon, Mexico].

PubMed

Manrique López, María Amelia; González Díaz, Sandra N; Arias Cruz, Alfredo; Sedó Mejía, Giovanni A; Canseco Villarreal, José Ignacio; Gómez Retamoza, Ernesto Antonio; Padrón López, Olga Magdalena; Cruz Moreno, Miguel Angel; Cisneros Salazar, Guillermo Daniel

2010-01-01

Allergic reactions to insect bites are a global problem, the true incidence and prevalence of morbidity from adverse reactions to mosquito bites are unknown. To describe the adverse reactions to mosquito bites in school-age children of Monterrey, Nuevo Leon. A cross-sectional descriptive study was made via a randomized application of questionnaires to children from public elementary schools in the metropolitan area of Monterrey, Nuevo Leon. A total of 11 public schools randomly selected were included in the study. One thousand questionnaires were submitted, of which 506 fulfilled the inclusion criteria; 55% were females. Seventy-six percent referred adverse reactions to mosquito bites, itching (75%) and rash (72%) being the most frequent ones, in the last 12 months. Adverse reactions to mosquito bites occur frequently. Early detection is important to establish a prompt treatment.

Early correction of unilateral scissor bite using transforce appliance and modified twin block appliance

PubMed Central

Chandorikar, Harshal; Nagrik, Arun; Bhad, Wasundhara A; Chavan, Santosh J; Doshi, Umal H

2017-01-01

Early treatment of scissor bite has been advocated mainly to prevent function jaw shift that can eventually lead to permanent skeletal asymmetry and temporomandibular joint pathosis. Although unilateral scissor bite is more common, most of the times, bilateral mandibular expansion is indicated. Lingual transforce appliance can be useful in such cases. This article presents a patient with unilateral scissor bite in mixed dentition with alveolar narrowing. Transforce appliance was used for scissor bite correction followed by modified twin block appliance for stabilization and settling of occlusion till the eruption of premolars. The case was finished with fixed mechanotherapy. Two years after completion of treatment, results were well maintained. Our results suggest that lingual transforce appliance along with careful management of occlusion is effective in the early management of severe unilateral scissor bite. PMID:28546961

Anterior open bite treatment with magnets.

PubMed

Kiliaridis, S; Egermark, I; Thilander, B

1990-11-01

The aim of this study was to examine the effects of repelling magnets on the treatment of anterior open bite and compare them with the effects of acrylic posterior bite-blocks. Twenty patients, aged 9-16 years with skeletal anterior open bite, were randomly divided into two groups. In one group the patients wore posterior repelling magnet splints and in the other they wore acrylic posterior bite-blocks of the same thickness as the magnet splints. The patients were instructed to use their appliance as much as possible (the minimum accepted being 18 hours daily) during a 6-month period. Dental casts, intra-oral photos, and lateral cephalograms were taken before and after treatment, and the patients were also examined regularly to identify the development of any craniomandibular disorders. In the first group, the dental and skeletal vertical relation responded quickly to the magnet treatment. The open bite was generally closed in just under 4 months, especially in patients in early mixed dentition. Spacing in the labial segments decreased in some cases, while slight crowding was induced in others. Transverse problems, i.e. unilateral cross-bite, sometimes followed by scissor-bite on the opposite side, was observed in those patients who were in the early mixed dentition and had used the magnets intensively. The patients who wore acrylic posterior bite-blocks also showed improvement in the dental and skeletal vertical relationships, especially during the first months. This was followed by a 'plateau' period. No transverse problems were found in these patients.

Oral Health Status among Children with Cerebral Palsy in Dubai, United Arab Emirates

PubMed Central

Al Hashmi, Haifa; Kowash, Mawlood; Hassan, Amar; Al Halabi, Manal

2017-01-01

Objectives: The purpose of this study was to assess the oral health status of children with cerebral palsy (CP) in Dubai, United Arab Emirates (UAE). Materials and Methods: Eighty-four CP and 125 healthy children were recruited from special needs centers and private/public schools in Dubai. A dental examination for decayed-missing-filled teeth in primary dentition (dmft)/Decayed-Missing-Filled teeth in permanent dentition (DMFT) indices, simplified oral hygiene index, calculus index (CI), and oral debris index was conducted. In addition, assessments of occlusal, dentofacial, soft tissue anomalies and erosion were conducted. Statistical analysis was conducted using SPSS for Windows, version 20.0 (SPSS Inc., Chicago, IL, USA). Results: DMFT/dmft scores were comparable in both groups. CI was significantly higher among children with CP. CP patients had a significantly higher proportion of anterior open bite, anterior spacing, Class II molar Angle malocclusion, trauma, high-arched palate, tongue thrust, lymphadenopathy, angular cheilitis, macroglossia, drooling, and erosion as compared to controls. Conclusions: The study highlighted peculiar characteristics and needs for the CP patients in Dubai, UAE. PMID:29285470

Evaluation of mandibular angle ostectomy using three-dimensional finite element analysis.

PubMed

Song, Jian; Zhu, Songsong; Luo, En; Hu, Jing; Feng, Ge

2014-07-01

This study was designed to investigate the stress and the displacement distributions of the mandible after mandibular angle ostectomy (MAO) by means of three-dimensional finite element analysis. On the basis of a female patient with a prominent angle of the mandible, the finite element models were generated by helical computed tomography and related software and were analyzed under muscle forces and 3 kinds of biting conditions, including intercuspal position (ICP), incisal clenching (INC), and right unilateral molar clenching (RMOL). The mandibular stress and displacement distributions were analyzed by Abaqus software. In the model of MAO, the increased stress and the decreased displacement was found in ICP, INC, and RMOL at the area of mandibular angle. The stress and the displacement increased in ICP and RMOL, whereas the others remained unchanged in INC at the area of mandibular condylar neck. The results of this study have shown that MAO could alter biomechanical characteristics in the operated mandible, which suggested that a greater hit on face may lead to a higher incidence rate of condyle fracture and a lower incidence rate of angle fracture after MAO.

Distribution and medical aspects of Loxosceles rufescens, one of the most invasive spiders of the world (Araneae: Sicariidae).

PubMed

Nentwig, Wolfgang; Pantini, Paolo; Vetter, Richard S

2017-06-15

Loxosceles rufescens is a circum-Mediterranean spider species, potentially harmful to humans. Its native area covers the Mediterranean Basin and Near East. Easily spread with transported goods, it is meanwhile an alien and invasive species to nearly all other continents and many islands. This species occurs in semi-arid steppe-like habitats, typically under stones and in cavities, which enables it to settle inside buildings when invading the synanthropic environment. This review analyses the literature of L. rufescens bites to humans (38 publications) of which only 11 publications refer to 12 verified spider bites (11% of the reported bites). Two published allegedly deadly spider bites (Thailand 2014 and Italy 2016) involve non-verified spider bites and are thus not reliable. The symptoms and therapy of these 11 verified bites are described: only five cases showed moderate systemic effects, nine cases developed necrosis, four cases needed surgical debridement, all cases healed without complications within a few weeks. In conclusion, L. rufescens is a spider species globally spread by human activity, it rarely bites humans and the bites are less harmful than often described. There is no known fatal issue. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative analysis of methods for determining bite force in the spiny dogfish Squalus acanthias.

PubMed

Huber, Daniel Robert; Motta, Philip Jay

2004-01-01

Many studies have identified relationships between the forces generated by the cranial musculature during feeding and cranial design. Particularly important to understanding the diversity of cranial form amongst vertebrates is knowledge of the generated magnitudes of bite force because of its use as a measure of ecological performance. In order to determine an accurate morphological proxy for bite force in elasmobranchs, theoretical force generation by the quadratomandibularis muscle of the spiny dogfish Squalus acanthias was modeled using a variety of morphological techniques, and lever-ratio analyses were used to determine resultant bite forces. These measures were compared to in vivo bite force measurements obtained with a pressure transducer during tetanic stimulation experiments of the quadratomandibularis. Although no differences were found between the theoretical and in vivo bite forces measured, modeling analyses indicate that the quadratomandibularis muscle should be divided into its constituent divisions and digital images of the cross-sections of these divisions should be used to estimate cross-sectional area when calculating theoretical force production. From all analyses the maximum bite force measured was 19.57 N. This relatively low magnitude of bite force is discussed with respect to the ecomorphology of the feeding mechanism of S. acanthias to demonstrate the interdependence of morphology, ecology, and behavior in organismal design. Copyright 2004 Wiley-Liss, Inc.

Dental health assessed after interproximal enamel reduction: caries risk in posterior teeth.

PubMed

Zachrisson, Björn U; Minster, Line; Ogaard, Bjørn; Birkhed, Dowen

2011-01-01

We investigated whether careful interdental enamel reduction (using extrafine diamond disks with air cooling, followed by contouring with triangular diamond burs and polishing) leads to increased caries risk in premolars and first molars. Our subjects were 43 consecutive patients from 19 to 71 years of age who had received mesiodistal enamel reduction of anterior and posterior teeth 4 to 6 years previously. Dental caries were assessed on standardized bite-wing radiographs according to a 5-grade scale and with a fine-tip explorer catch. The incidence of interproximal caries was compared between reproximated and unground contralateral surfaces in the same patient. Patients were asked about their toothbrushing habits, use of dental floss and toothpicks, and regular fluoride supplementation after the orthodontic appliances were removed. The overall clinical impression generally showed healthy dentitions with excellent occlusion. Only 7 (2.5%) new caries lesions (all grade 1) were found among 278 reproximated mesial or distal surfaces, in 3 patients. Among 84 contralateral unground reference tooth surfaces, 2 lesions (2.4%) were seen. On nonpaired premolars and molars that had not been ground, 23 surfaces had to be referred for caries treatment (grade 3 or occlusal caries). Eleven of these occurred in 1 patient. None of the 43 patients reported increased sensitivity to temperature variations. Interdental enamel reduction with this protocol did not result in increased caries risk in posterior teeth. We found no evidence that proper mesiodistal enamel reduction within recognized limits and in appropriate situations will cause harm to the teeth and supporting structures. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Multifactorial etiology of Torus mandibularis: study of twins.

PubMed

Auškalnis, Adomas; Rutkūnas, Vygandas; Bernhardt, Olaf; Šidlauskas, Mantas; Šalomskienė, Loreta; Basevičienė, Nomeda

2015-01-01

The aim of this study is to investigate the multifactorial etiology of mandibular tori analyzing the influence of genetics, occlusal overload, various clinical variables and their interactions. Overall, plaster casts of 162 twins (81 twin pairs) were analyzed for the presence or absence of mandibular tori. Atypical wear facets on canine tips or incisors were recorded to diagnose bruxism. Angle Class, any kind of anterior open bite and positive, negative or flat curve of Wilson were recorded. Zygosity determination was carried out using a DNA test. Mandibular tori were found in 56.8% of the cases. In 93.6% of all monozygotic twin pairs both individuals had or did not have mandibular tori (κ=0.96±0.04; p<0.001), compared to 79.4% concordance of mandibular tori in dizygotic co-twins (κ=0.7±0.12; p<0.001). Prevalence of mandibular tori was significantly higher in the group of bruxers (67.5%) compared to non-bruxers (31.3%) (p<0.001). Significant association between mandibular tori and negative or flat curve of Wilson in the maxillary second premolars and first molars was found (OR=2.55, 95% CI (1.19-5.46), p=0.016). In all monozygotic bruxers, 97.1% showed concordance of mandibular tori presence in both co-twins compared to 78.9% dizygotic bruxers, and this difference is statistically significant (p=0.007). Our results suggest that the mandibular tori are of a multifactorial origin. Mandibular tori seem to have genetic predisposition, and may be associated with teeth grinding as well as with negative or flat CW in region of maxillary second premolar and first molar.

A Multi-Site Study on Knowledge, Attitudes, Beliefs and Practice of Child-Dog Interactions in Rural China

PubMed Central

Shen, Jiabin; Li, Shaohua; Xiang, Huiyun; Pang, Shulan; Xu, Guozhang; Schwebel, David C.

2013-01-01

This study examines demographic, cognitive and behavioral factors that predict pediatric dog-bite injury risk in rural China. A total of 1,537 children (grades 4–6) in rural regions of Anhui, Hebei and Zhejiang Provinces, China completed self-report questionnaires assessing beliefs about and behaviors with dogs. The results showed that almost 30% of children reported a history of dog bites. Children answered 56% of dog-safety knowledge items correctly. Regressions revealed both demographic and cognitive/behavioral factors predicted children’s risky interactions with dogs and dog-bite history. Boys behaved more riskily with dogs and were more frequently bitten. Older children reported greater risks with dogs and more bites. With demographics controlled, attitudes/beliefs of invulnerability, exposure frequency, and dog ownership predicted children’s self-reported risky practice with dogs. Attitudes/beliefs of invulnerability, dog exposure, and dog ownership predicted dog bites. In conclusion, both demographic and cognitive/behavioral factors influenced rural Chinese children’s dog-bite injury risk. Theory-based, empirically-supported intervention programs might reduce dog-bite injuries in rural China. PMID:23470881

Effectiveness of permethrin-treated clothing to prevent tick exposure in foresters in the central Appalachian region of the USA.

PubMed

L Richards, Stephanie; G Balanay, Jo Anne; W Harris, Jonathan

2015-01-01

Outdoor workers are at risk from mosquito and tick bites and the extent to which exposures are linked to vector-borne disease is not understood. This pilot study characterizes for ester exposure to mosquitoes and ticks, and assesses effectiveness of permethrin-treated clothing for prevention of tick bites. Foresters (N = 34) from Kentucky, North Carolina, Ohio, Tennessee, Virginia, and West Virginia were placed into treatment (permethrin-treated clothing) or control (untreated clothing) groups. Foresters completed questionnaires about work-related tick/mosquito exposure and 454 ticks were collected/identified from May to June 2013. A time-weighted analysis based on information submitted by foresters about time working outdoors showed that control participants received a lower rate of tick exposure (0.15 tick bites/hour; 13 bites/person) compared to treatment participants (0.27 bites/hour; 21 bites/person). However, more control participants (85 %) received at least one tick bite compared to treatment participants (52 %). Outdoor workers should be aware of available protective measures, such as permethrin-treated clothing, that may mitigate occupational risks.

Tick Talk: Block Tick Bites and Lyme Disease

MedlinePlus

... Subscribe May 2014 Print this issue Tick Talk Block Tick Bites and Lyme Disease En español Send ... Health Researchers Examine the Structure of Zika Virus Block the Buzzing, Bites, and Bumps Wise Choices To ...

Spider Bites: First Aid

MedlinePlus

... United States, its range is central and southern states. Signs and symptoms of a brown recluse spider bite vary but may include: At first, a mild pain Redness and intense pain A deep blue or purple area around the bite, which ...

Rat bite fever in a pet lover.

PubMed

Cunningham, B B; Paller, A S; Katz, B Z

1998-02-01

Rat-bite fever is an uncommon bacterial illness resulting from infection with Streptobacillus moniliformis that is often transmitted by the bite of a rat. The cutaneous findings in rat-bite fever are nonspecific but have been described as maculopapular or petechial. We describe a 9-year-old girl with acrally distributed hemorrhagic pustules, fever, and arthralgias. Diagnosis was delayed because of difficulty in identifying the pathologic organism. She was successfully treated with 10 days of ceftriaxone.

Prospective audit of 106 consecutive human bite injuries: the importance of history taking

PubMed Central

Wallace, C; Robertson, C

2005-01-01

Methods: Patients with cutaneous wounds who did not present with a history of human bite were asked a follow up question. Those who then gave a history of human bite were noted. Results: Certain groups of patients with human bites were significantly more likely to provide a factitious history and/or delay presentation. Conclusion: Follow up questioning dramatically increased the case-detection rate, prompting specific management. PMID:16299201

Deadly case of Pasteurella multocida aortitis and mycotic aneurysm following a cat bite.

PubMed

Cho, Dennis Dane; Berliner, Yaniv; Carr, David

2016-06-16

Animal bites are frequently encountered in the emergency department (ED). Aortitis leading to mycotic abdominal aortic aneurysm is a rare and potentially deadly complication of Pasteurella multocida (P. multocida) following an animal bite. We present the case of a 68-year-old male who presented to the ED after falling at home. He complained of weakness and abdominal pain. He was in septic shock and was treated empirically with broad-spectrum antibiotics and intravenous fluids. He reported previous antibiotic treatment of a cellulitis secondary to a cat bite injury to his right thumb four weeks prior. Abdominal ultrasound and subsequent computed tomography scan revealed a leaking mycotic abdominal aneurysm that was surgically repaired. Blood cultures and aortic wall tissue cultures grew P. multocida. Given how common animal bite presentations are in the ED, this case highlights the need to consider aortitis and mycotic abdominal aortic aneurysm in an unwell patient with an animal bite.

First bite syndrome: our experience of laser tympanic plexus ablation.

PubMed

Amin, N; Pelser, A; Weighill, J

2014-02-01

First bite syndrome is a condition characterised by severe facial pain brought on by the first bite of each meal. This can severely affect the patient's ability to eat. We present a 70-year-old woman for whom we performed a laser ablation of the left ear tympanic plexus, as treatment of first bite syndrome. A permeatal approach was used to raise a tympanomeatal flap. The tympanic plexus was identified on the promontory and a 4 mm2 area of the plexus was ablated using CO2 laser. The flap was repositioned and a dressing was placed with topical antibiotics. At two-month follow up, there was full resolution of the patient's symptoms. First bite syndrome carries a high morbidity; treatment options are variable, and often unsuccessful. We describe the first documented case of laser tympanic plexus ablation, with a very effective initial response. This procedure represents a useful therapeutic option for first bite syndrome.

U.S. Army soldiers' perceptions of arthropod pests and their effects on military missions.

PubMed

Mehr, Z A; Rutledge, L C; Echano, N M; Gupta, R K

1997-12-01

A survey was conducted to determine the effects of biting and stinging arthropods on military personnel, operations, and training. Nearly 70% of respondents reported experiencing problems attributable to arthropods. Arthropods obstructed movement and field position, prevented concealment and cover, disrupted maneuvers, and caused panic. Twenty percent of respondents reported attendance at sick call for treatment of bites or stings, and 4% were hospitalized or assigned to quarters. Median lost time was 2 days. Bee, wasp, and ant stings and spider and chigger bites were the most frequent causes of lost time. Additional training on biting and stinging arthropods, use of repellents and other personal protective measures, first aid for bites and stings, and conditions requiring medical attention is needed in field units to enhance mission performance and reduce time lost because of arthropods. Materials for treatment of bites and stings should be included in first-aid kits issued for field use.

Selective flotation-spectrophotometric determination of trace copper(II) in natural waters, human blood and drug samples using phenanthraquinone monophenylthiosemicarbazone.

PubMed

Khalifa, M E; Akl, M A; Ghazy, S E

2001-06-01

Copper(II) forms 1:1 and 1:2 intense red complexes with phenanthraquinone monophenylthiosemicarbazone (PPT) at pH 3-3.5 and > or =6.5, respectively. These complexes exhibit maximal absorbance at 545 and 517 nm, the molar absorptivity being 2.3 x 10(4) and 4.8 x 10(4) l mol(-1) cm(-1), respectively. However, the 1:1 complex was quantitatively floated with oleic acid (HOL) surfactant in the pH range 4.5-5.5, providing a highly selective and sensitive procedure for the spectrophotometric determination of CuII. The molar absorptivity of the floated Cu-PPT complex was 1.5 x 10(5) l mol)(-1) cm(-1). Beer's law was obeyed over the range 3-400 ppb at 545 nm. The analytical parameters affecting the flotation process and hence the determination of copper traces were reported. Also, the structure of the isolated solid complex and the mechanism of flotation were suggested. Moreover, the procedure was successfully applied to the analysis of CuII in natural waters, serum blood and some drug samples.

Taking the Bite out of Bruxism (For Kids)

MedlinePlus

... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body Works ... Taking the Bite Out of Bruxism KidsHealth / For Kids / Taking the Bite Out of Bruxism Print Do ...

Quantifying seasonal and diel variation in Anopheline and Culex human biting rates in Southern Ecuador.

PubMed

Ryan, Sadie J; Lippi, Catherine A; Boersch-Supan, Philipp H; Heydari, Naveed; Silva, Mercy; Adrian, Jefferson; Noblecilla, Leonardo F; Ayala, Efraín B; Encalada, Mayling D; Larsen, David A; Krisher, Jesse T; Krisher, Lyndsay; Fregosi, Lauren; Stewart-Ibarra, Anna M

2017-11-22

Quantifying mosquito biting rates for specific locations enables estimation of mosquito-borne disease risk, and can inform intervention efforts. Measuring biting itself is fraught with ethical concerns, so the landing rate of mosquitoes on humans is often used as a proxy measure. Southern coastal Ecuador was historically endemic for malaria (Plasmodium falciparum and Plasmodium vivax), although successful control efforts in the 2000s eliminated autochthonous transmission (since 2011). This study presents an analysis of data collected during the elimination period. Human landing catch (HLC) data for three mosquito taxa: two malaria vectors, Anopheles albimanus and Anopheles punctimacula, and grouped Culex spp. were examined for this study. These data were collected by the National Vector Control Service of the Ministry of Health over a 5-year time span (2007-2012) in five cities in southern coastal Ecuador, at multiple households, in all months of the year, during dusk-dawn (18:00-6:00) hours, often at both indoor and outdoor locations. Hurdle models were used to determine if biting activity was fundamentally different for the three taxa, and to identify spatial and temporal factors influencing bite rate. Due to the many different approaches to studying and quantifying bite rates in the literature, a glossary of terms was created, to facilitate comparative studies in the future. Biting trends varied significantly with species and time. All taxa exhibited exophagic feeding behavior, and outdoor locations increased both the odds and incidence of bites across taxa. Anopheles albimanus was most frequently observed biting, with an average of 4.7 bites/h. The highest and lowest respective months for significant biting activity were March and July for An. albimanus, July and August for An. punctimacula, and February and July for Culex spp. Fine-scale differences in endophagy and exophagy, and temporal differences among months and hours exist in biting patterns among mosquito taxa in southern coastal Ecuador. This analysis provides detailed information for targeting vector control activities, and household level vector prevention strategies. These data were collected as part of routine vector surveillance conducted by the Ministry of Health, and such data have not been collected since. Reinstating such surveillance measures would provide important information to aid in preventing malaria re-emergence.

Pilot study assessing the effectiveness of factory-treated, long-lasting permethrin-impregnated clothing for the prevention of tick bites during occupational tick exposure in highly infested military training areas, Germany.

PubMed

Faulde, Michael K; Rutenfranz, Martin; Keth, Alexander; Hepke, Jürgen; Rogge, Mareike; Görner, Andreas

2015-02-01

The protective effectiveness of factory-based permethrin-impregnated polymer-coated battle dress uniforms (PTBDUs) against tick bites was evaluated at four military training areas in southwestern and central Germany where tick bite incidence is known to be high. Data were analyzed by comparing tick bite incidence using non-permethrin-treated BDUs (NTBDUs) during 2009 versus PTBDUs during 2010 and 2011, the first two years after their formal introduction for in-country use in the German Bundeswehr. During 2009, 262 individual tick bites were reported at the four training sites, resulting in a tick bite incidence of 8.8 % per exposed person when wearing NTBDUs only. In 2010 and 2011, one tick bite case occurred under field conditions each year that PTBDUs were worn, corresponding to a protective effectiveness of 99.6 and 98.6 %. These data imply an annual tick bite incidence of 0.035 and 0.078 % per exposed person, respectively. Between 2010 and 2011, a 0.8 % decline in the protective effectiveness of PTBDUs was observed. Five tick bite incidents occurred while wearing non-impregnated parkas over correctly worn PTBDUs. Ixodes ricinus ticks were collected by standard tick drags from 2009 to 2011, with high mean annual densities ranging from 28.9 to 106.5 ticks per 100 m(2), while single drags revealed tick densities between zero and 381 ticks per 100 m(2). Overall, 4596 I. ricinus ticks (54 ♂, 82 ♀, 1776 nymphs, and 2684 larvae) were collected, of which 128 (2.8 %; mean annual range, 0-10.1 %) were Borrelia burgdorferi s.l. positive. The Borrelia genospecies distribution was as follows: 112 (87.5 %) Borrelia afzelii, 10 (7.8 %) B. burgdorferi s.s., and 6 (4.7 %) Borrelia garinii. Neither the tick density means from 2009 to 2011 nor associated B. burgdorferi s.l. prevalences differed significantly among the military locations investigated. The documented tick bite reductions clearly demonstrate the powerful protective effectiveness of properly worn PTBDUs against tick bites. Nevertheless, all apparel worn over PTBDUs should also be impregnated with permethrin in order to prevent tick infestation and subsequent bites.

Examining evidence on dog bite injuries and their management in children.

PubMed

Elizabeth Murray, Gemma

2017-04-11

Dog bites are common injuries in children. The effects of such injuries can be devastating for the children concerned and their families. It is therefore important to provide holistic care and to consider psychological well-being as well as physical recovery. There should be clear guidelines for professionals about reporting dog bites and safeguarding. The literature recommends primary closure of the dog bite wound unless an infection is present. Literature also suggests that prophylactic antibiotics are ineffective in preventing infection except in hand injuries, although they are still routinely used in practice. This article recommends further research, support and education on dog bites in children, as well as national guidelines.

[Bites of venomous snakes in Switzerland].

PubMed

Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

2016-06-08

Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.

Bite by a dog under provocation: is it free from risk?

PubMed

Dutta, J K

2002-05-01

There is a common belief that rabid dogs bite without provocation, hence a dog bite under provocation is free from the risk of rabies. This is not always true as is evident from the case report narrated below. Here in this article, a man of 38 years was bitten by a dog under provocation. He developed rabies 4 months after the bite and subsequently died. Autopsy revealed Negri bodies from the brain tissue.

Patients' and therapists' experiences of general change mechanisms during bug-in-the-eye and delayed video-based supervised cognitive-behavioral therapy. A randomized controlled trial.

PubMed

Probst, Thomas; Jakob, Marion; Kaufmann, Yvonne M; Müller-Neng, Julia M B; Bohus, Martin; Weck, Florian

2018-04-01

This secondary analysis of a randomized controlled trial investigated whether bug-in-the-eye (BITE) supervision (live computer-based supervision during a psychotherapy session) affects the manner in which patients and therapists experience general change mechanisms (GCMs) during cognitive-behavioral therapy (CBT). A total of 23 therapists were randomized either to the BITE condition or the control condition (delayed video-based [DVB] supervision). After each session, both patients (BITE: n = 19; DVB: n = 23) and therapists (BITE: n = 11; DVB: n = 12) completed the Helping Alliance Questionnaire (HAQ) and the Bernese Post Session Report (BPSR). The HAQ total score and the 3 secondary factors of the BPSR (interpersonal experiences, intrapersonal experiences, problem actuation) functioned as GCMs. Multilevel models were performed. For patients, GCMs did not develop differently between BITE and DVB during CBT. Therapists rated the alliance as well as interpersonal and intrapersonal experiences not significantly different between BITE and DVB during CBT, but they perceived problem actuation to increase significantly more in BITE than in DVB (p < .05). BITE supervision might be helpful in encouraging CBT therapists to apply interventions, which focus on the activation of relevant problems and related emotions. © 2017 Wiley Periodicals, Inc.

Dental image replacement on cone beam computed tomography with three-dimensional optical scanning of a dental cast, occlusal bite, or bite tray impression.

PubMed

Kang, S-H; Lee, J-W; Lim, S-H; Kim, Y-H; Kim, M-K

2014-10-01

The goal of the present study was to compare the accuracy of dental image replacement on a cone beam computed tomography (CBCT) image using digital image data from three-dimensional (3D) optical scanning of a dental cast, occlusal bite, and bite tray impression. A Bracket Typodont dental model was used. CBCT of the dental model was performed and the data were converted to stereolithography (STL) format. Three experimental materials, a dental cast, occlusal bite, and bite tray impression, were optically scanned in 3D. STL files converted from the CBCT of the Typodont model and the 3D optical-scanned STL files of the study materials were image-registered. The error range of each methodology was measured and compared with a 3D optical scan of the Typodont. For the three materials, the smallest error observed was 0.099±0.114mm (mean error±standard deviation) for registering the 3D optical scan image of the dental cast onto the CBCT dental image. Although producing a dental cast can be laborious, the study results indicate that it is the preferred method. In addition, an occlusal bite is recommended when bite impression materials are used. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Condylar position analysis with a new electronic condylar position measuring instrument E-CPM: influence of different examiners and a working bite on reproducibility.

PubMed

Vahle-Hinz, K; Rybczynski, A; Jakstat, H; Ahlers, M O

2009-01-01

Condylar position analysis facilitates a quantitative comparison of the condylar position with and without a bite record, different records and changed influencing factors. Handling by the examiner when positioning the model is a significant factor with regard to the accuracy of the examination. Measurement accuracy could be improved when positioning the models by using special working bites, hence the objective of the experiments described in this study consisted in examining the extent to which the measuring results are influenced by different examiners and by using working bites. In the first trial, one examiner performed ten measurements without and with an interposed working bite for five model pairs in each case. In the second trial, nine examiners (three specialized dentists, three dental assistants, three students) performed ten measurements in each case without and with an interposed working bite. The three-dimensional position was read digitally with the E-CPM (Gamma Dental, Klosterneuburg/Vienna, Austria), recorded by means of spreadsheet software (Microsoft Excel) and diagnostic software (CMDfact, CMD3D module, dentaConcept, Hamburg), and evaluated with graphing software (Sigma Plot, Systat Software, USA). In the first trial, it was shown that the reproducibility of mounting was improved markedly (p <0.01) by using bite records in the form of working bites. In the second trial, it was shown that the mean error increased significantly (p <0.01) when several examiners performed the measurements compared with the results of one examiner alone. No significantly different results occurred (p < 0.01) in the comparison of the different groups of examiners with different educational and training backgrounds. This applied for the mounting methods without and with working bite. On the other hand, the reproducibility of mounting improved distinctly (p<0.01) in every group of examiners when working bites were used. Reproducibility of condylar position analysis was improved significantly by mounting the models with special working bites. This applied for operators of different professional background (dentists, dental assistants and dental students), while there were no significant differences between results of the three groups.

Factors Associated With Bites to a Child From a Dog Living in the Same Home: A Bi-National Comparison.

PubMed

Messam, Locksley L McV; Kass, Philip H; Chomel, Bruno B; Hart, Lynette A

2018-01-01

We conducted a veterinary clinic-based retrospective cohort study aimed at identifying child-, dog-, and home-environment factors associated with dog bites to children aged 5-15 years old living in the same home as a dog in Kingston, Jamaica (236) and San Francisco, USA (61). Secondarily, we wished to compare these factors to risk factors for dog bites to the general public. Participant information was collected via interviewer-administered questionnaire using proxy respondents. Data were analyzed using log-binomial regression to estimate relative risks and associated 95% confidence intervals (CIs) for each exposure-dog bite relationship. Exploiting the correspondence between X% confidence intervals and X% Bayesian probability intervals obtained using a uniform prior distribution, for each exposure, we calculated probabilities of the true (population) RRs ≥ 1.25 or ≤0.8, for positive or negative associations, respectively. Boys and younger children were at higher risk for bites, than girls and older children, respectively. Dogs living in a home with no yard space were at an elevated risk (RR = 2.97; 95% CI: 1.06-8.33) of biting a child living in the same home, compared to dogs that had yard space. Dogs routinely allowed inside for some portion of the day (RR = 3.00; 95% CI: 0.94-9.62) and dogs routinely allowed to sleep in a family member's bedroom (RR = 2.82; 95% CI: 1.17-6.81) were also more likely to bite a child living in the home than those that were not. In San Francisco, but less so in Kingston, bites were inversely associated with the number of children in the home. While in Kingston, but not in San Francisco, smaller breeds and dogs obtained for companionship were at higher risk for biting than larger breeds and dogs obtained for protection, respectively. Overall, for most exposures, the observed associations were consistent with population RRs of practical importance (i.e., RRs ≥ 1.25 or ≤0.8). Finally, we found substantial consistency between risk factors for bites to children and previously reported risk factors for general bites.

Effect of the route of administration of methylprednisolone on oedema and trismus in impacted lower third molar surgery.

PubMed

Koçer, G; Yuce, E; Tuzuner Oncul, A; Dereci, O; Koskan, O

2014-05-01

Due to their anatomical position, the surgical removal of impacted third molars results in oedema, pain, and trismus. The purpose of this study was to evaluate the efficacy of supraperiosteal injection of methylprednisolone compared with an oral tablet form and intravenous (i.v.) injection in the prevention of postoperative pain and oedema associated with inflammation. This randomized, prospective, and controlled study included 44 patients. The patients were randomly divided into four groups: group 1 (control; no steroids), group 2 (local injection), group 3 (oral tablets), and group 4 (i.v. injection). On days 2 and 7 following surgery, linear oedema was determined using facial landmarks, and maximal mouth opening was measured. Postoperative mouth opening and swelling were evaluated for each route of methylprednisolone administration and compared. The female (59%) to male (41%) ratio was 1.44; the mean age of the patients was 29.6 years. The level of significance was set at P<0.01 for mouth opening and P<0.05 for oedema. With regard to trismus, all three routes of administration demonstrated better efficacy in comparison to the control. While oral administration and i.v. injection of methylprednisolone achieved similar results, masseter injection provided better results in reducing oedema and trismus when compared to the control following lower third molar surgery. Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Barium recovery by crystallization in a fluidized-bed reactor: effects of pH, Ba/P molar ratio and seed.

PubMed

Su, Chia-Chi; Reano, Resmond L; Dalida, Maria Lourdes P; Lu, Ming-Chun

2014-06-01

The effects of process conditions, including upward velocity inside the column, the amount of added seed and seed size, the pH value of the precipitant or the phosphate stream and the Ba/P molar ratio in a fluidized-bed reactor (FBR) were studied with a view to producing BaHPO₄ crystals of significant size and maximize the removal of barium. XRD were used to identify the products that were collected from the FBR. Experimental results show that an upward velocity of 48 cmmin(-1) produced the largest BaHPO₄ crystals with a size of around 0.84-1.0mm. The addition of seed crystals has no effect on barium removal. The use of a seed of a size in the ranges unseeded<0.149-0.29 mm<0.149 mm<0.29-0.42 mm produced increasing amounts of increasingly large crystals. The largest BaHPO₄ crystals were obtained at pH 8.4-8.8 with a Ba/P molar ratio of 1.0. In the homogeneous and heterogeneous processes, around 98% of barium was removed at pH 8.4-8.6 and [Ba]/[P]=1.0. The XRD results show that a significant amount of barium phosphate (Ba₃(PO₄)₂) was obtained at pH 11. The compounds BaHPO₄ and BaO were present at a pH of below 10. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of adhesive surface and volume of luting resin on fracture resistance of root filled teeth.

PubMed

Krastl, G; Gugger, J; Deyhle, H; Zitzmann, N U; Weiger, R; Müller, B

2011-05-01

To investigate the correlation between geometric parameters of severely compromised root filled (RCT) pre-molar teeth with irregular root canals and their fracture resistance. The null hypothesis tested was that the fracture resistance of root filled teeth is not influenced by: (i) the adhesive surface of the post-space preparation (A(PS) ), (ii) the coronal tooth surface (A(A) ), (iii) the amount of resin cement (V(C) ) and (iv) the Young's modulus of the specimens. A total of 48 noncarious human pre-molar teeth with irregular root canals were decoronated, root filled and adhesively restored with post-retained direct composite crowns. After thermomechanical loading (1,200,000×, 5-50° C), static load was applied until failure. The geometric parameters of the tooth were evaluated by microcomputed tomography (μCT) using impressions taken after post-space preparation. Linear regression analyses were performed to correlate the geometric parameters of the specimens with their fracture resistance. The amount of resin cement (V(C) ) comprised up to 88% of the entire post-space (mean 67%) and had no impact on the maximal load (P = 0.88). The latter was significantly influenced by post-space preparation (P = 0.003). Amongst the geometric parameters tested, the surface area in the root canal had the greatest impact on fracture resistance of root filled pre-molars restored with posts and composite crowns, whilst the fit of the post was less important. © 2011 International Endodontic Journal.

Dramatic increase in sea otter mortality from white sharks in California

USGS Publications Warehouse

Tinker, M. Tim; Hatfield, Brian B.; Harris, Michael D.; Ames, Jack A.

2016-01-01

Although southern sea otters (Enhydra lutris nereis) are not considered prey for white sharks (Carcharodon carcharias), sharks do nonetheless bite sea otters. We analyzed spatial and temporal trends in shark bites on sea otters in California, assessing the frequency of shark bite wounds in 1,870 carcasses collected since 1985. The proportion of stranded sea otters having shark bites has increased sharply since 2003, and white shark bites now account for >50% of recovered carcasses. The trend was most pronounced in the southern part of the range, from Estero Bay to Point Conception, where shark bite frequency has increased eightfold. Seasonal trends were also evident: most shark-bitten carcasses are recovered in late summer and fall; however, the period of elevated shark bite frequency has lengthened. The causes of these trends are unclear, but possible contributing factors include increased white shark abundance and/or changes in white shark behavior and distribution. In particular, the spatiotemporal patterns of shark-bitten sea otters match increases in pinniped populations, and the increased availability of marine mammal prey for white sharks may have led to more sharks spending more time in nearshore waters utilized by both sea otters and pinnipeds.

The effect of short-term prevention on the subsequent rate of crib-biting in thoroughbred horses.

PubMed

McGreevy, P D; Nicol, C J

1998-11-01

The results of an experimental study of the motivational consequences of short-term prevention of crib-biting are reported here. Eight test horses wore a cribbing collar for 24 h. This was effective in preventing crib-biting in 6 subjects. Using analysis of co-variance that accounted for baseline differences in crib-biting rate, test horses showed significantly more crib-biting than control horses on the first day after prevention (P < 0.05). There was also a highly significant increase in the crib-biting rate of test horses on the first day after prevention in comparison with their baseline rate (P < 0.01). This defines the increase as a post inhibitory rebound. An increase in the novelty of the cribbing bar and an increase in feeding motivation during the period of prevention are rejected as explanations of the rebound in this study. Instead, it is suggested that the rebound reflected a rise in internal motivation to crib-bite during the period of prevention. Behaviours that exhibit this pattern of motivation are generally considered functional; and it has been argued that their prevention may compromise welfare.

Factors associated with the prevalence of anterior open bite among preschool children: A population-based study in Brazil

PubMed Central

Machado, Daniella Borges; Brizon, Valéria Silva Cândido; Ambrosano, Gláucia Maria Bovi; Madureira, Davidson Fróis; Gomes, Viviane Elisângela; de Oliveira, Ana Cristina Borges

2014-01-01

INTRODUCTION: The aim of this study was to identify factors associated with the prevalence of anterior open bite among five-year-old Brazilian children. METHODS: A cross-sectional study was undertaken using data from the National Survey of Oral Health (SB Brazil 2010). The outcome variable was anterior open bite classified as present or absent. The independent variables were classified by individual, sociodemographic and clinical factors. Data were analyzed through bivariate and multivariate analysis using SPSS statistical software (version 18.0) with a 95% level of significance. RESULTS: The prevalence of anterior open bite was 12.1%. Multivariate analysis showed that preschool children living in Southern Brazil had an increased chance of 1.8 more times of having anterior open bite (CI 95%: 1.16 - 3.02). Children identified with alterations in overjet had 14.6 times greater chances of having anterior open bite (CI 95%: 8.98 - 24.03). CONCLUSION: There was a significant association between anterior open bite and the region of Brazil where the children lived, the presence of altered overjet and the prevalence of posterior crossbite. PMID:25715723

Taking the Bite Out of Vector-Borne Diseases

MedlinePlus

... the 'Bite' Out of Vector-Borne Diseases Inside Life Science View All Articles | Inside Life Science Home Page Taking the 'Bite' Out of Vector- ... Science Solving the Sleeping Sickness 'Mystery' This Inside Life Science article also appears on LiveScience . Learn about related ...

Metabolic Engineering of Raoultella ornithinolytica BF60 for Production of 2,5-Furandicarboxylic Acid from 5-Hydroxymethylfurfural

PubMed Central

Hossain, Gazi Sakir; Yuan, Haibo; Li, Jianghua; Shin, Hyun-dong; Wang, Miao; Du, Guocheng; Chen, Jian

2016-01-01

ABSTRACT 2,5-Furandicarboxylic acid (FDCA) is an important renewable biotechnological building block because it serves as an environmentally friendly substitute for terephthalic acid in the production of polyesters. Currently, FDCA is produced mainly via chemical oxidation, which can cause severe environmental pollution. In this study, we developed an environmentally friendly process for the production of FDCA from 5-hydroxymethyl furfural (5-HMF) using a newly isolated strain, Raoultella ornithinolytica BF60. First, R. ornithinolytica BF60 was identified by screening and was isolated. Its maximal FDCA titer was 7.9 g/liter, and the maximal molar conversion ratio of 5-HMF to FDCA was 51.0% (mol/mol) under optimal conditions (100 mM 5-HMF, 45 g/liter whole-cell biocatalyst, 30°C, and 50 mM phosphate buffer [pH 8.0]). Next, dcaD, encoding dicarboxylic acid decarboxylase, was mutated to block FDCA degradation to furoic acid, thus increasing FDCA production to 9.2 g/liter. Subsequently, aldR, encoding aldehyde reductase, was mutated to prevent the catabolism of 5-HMF to HMF alcohol, further increasing the FDCA titer, to 11.3 g/liter. Finally, the gene encoding aldehyde dehydrogenase 1 was overexpressed. The FDCA titer increased to 13.9 g/liter, 1.7 times that of the wild-type strain, and the molar conversion ratio increased to 89.0%. IMPORTANCE In this work, we developed an ecofriendly bioprocess for green production of FDCA in engineered R. ornithinolytica. This report provides a starting point for further metabolic engineering aimed at a process for industrial production of FDCA using R. ornithinolytica. PMID:27795308

Attempted suicide by snake bite: A case study.

PubMed

Mallik, Subhendu; Singh, Sudipta Ranjan; Mohanty, Manoj Kumar; Padhy, Niranjan

2016-07-14

Snake bite is an important public health issue in India and is almost always accidental in manner. Suicide by snake bite or injection of snake venom is extremely rare. Suicidal ideation and behavior is known to be influenced by various socio-economic and psychological factors. The method employed for suicide is also influenced by the occupation of the victim. We report a case where a snake charmer had attempted suicide by inflicting a bite by a monocled cobra. © The Author(s) 2016.

Fe-FeS2 adsorbent prepared with iron powder and pyrite by facile ball milling and its application for arsenic removal.

PubMed

Min, Xiaobo; Li, Yangwenjun; Ke, Yong; Shi, Meiqing; Chai, Liyuan; Xue, Ke

2017-07-01

Arsenic is one of the major pollutants and a worldwide concern because of its toxicity and chronic effects on human health. An adsorbent of Fe-FeS 2 mixture for effective arsenic removal was successfully prepared by mechanical ball milling. The products before and after arsenic adsorption were characterized with scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorbent shows high arsenic removal efficiency when molar ratio of iron to pyrite is 5:5. The experimental data of As(III) adsorption are fitted well with the Langmuir isotherm model with a maximal adsorption capacity of 101.123 mg/g. And As(V) data were described perfectly by the Freundlich model with a maximal adsorption capacity of 58.341 L/mg. As(III) is partial oxidized to As(V) during the adsorption process. High arsenic uptake capability and cost-effectiveness of waste make it potentially attractive for arsenic removal.

Distraction of the temporomandibular joint condyle in patients with unilateral non-reducing disc displacement: Fact or fiction?

PubMed

Yıldız, Melih; Çağatay Dayan, Süleyman; Şakar, Olcay; Sülün, Tonguç

2017-07-24

This study investigated the distractive effect of a unilateral pivot splint on patients with unilateral disc displacement without reduction. The study group was comprised of 18 patients who had no history of treatment with removable prosthetic restorations of molars, premolars, or canine teeth, and no previous treatment for temporomandibular disorder. Joint spaces measurements made on magnetic resonance images indicated the affected side to be narrower than the healthy side. Unilateral distraction splints were made for all patients. An ultrasonic motion analyzer was used to measure the vertical shift occurring on the affected side as patients closed their mouths with maximal force with the splint in their mouths. Closing with maximal force on the unilateral distraction splint led to a noticeable downward movement of the affected condyle. The findings of this study indicate that the TMJ condyle of patients with unilateral disc displacement without reduction may be unilaterally distracted if the articular space is narrowed.

Level and pattern of human rabies and dog bites in Techiman Municipality in the Middle Belt of Ghana: a six year retrospective records review

PubMed Central

Punguyire, Damien Tioyire; Osei-Tutu, Anthony; Aleser, Emmanuel Vikpenibe; Letsa, Timothy

2017-01-01

Introduction Rabies is a viral zoonotic disease that is transmitted primarily by bites from rabid dogs and has the highest case fatality rate of most infectious diseases in humans. We described a 6-year trend of rabies and dog bites in a peri-urban district in Ghana. Methods A record review was conducted in the health facilities in Techiman to identify all human rabies and dog bite cases reported from January 2011 to December 2016. Rabies and dog bite data were extracted from health facilities records. Vaccination status of implicated dogs was extracted from the veterinary records at the Techiman Disease Investigation Farm. Data were summarized using proportions and presented using tables, charts and figures. Results Thirteen (13) cases of human rabies were recorded from 2011 to 2016. Complete data was available for 10 cases. Median age of rabies victims was 30 (range 3-80 years). A majority were males (8 representing 61.5%). Eight cases came from rural farming communities, 8 had a previous history of dog bite ranging from two weeks to five months before the onset of rabies symptoms and one reported with non-bite rabies. Case fatality was 100%. A total of 680 dog bites were reported by health facilities. About 50.3% (342) of the victims were males, a majority of bites (47.9%) occurred among children aged 1-15 years. Positive rabies cases among offending dogs ranged from 3.3% in 2016 to 17.6% in 2014. Conclusion Mass vaccination of dogs and provision of post-exposure vaccination are needed to reduce rabies transmission. PMID:29942413

Long-term complications of rattlesnake bites: a telephone survey from Central California.

PubMed

Spano, Susanne J; Vohra, Rais; Macias, Fernando

2014-06-01

The purpose of this institutional review board-approved, cross-sectional study was to identify residual symptoms and signs of envenomation reported by snakebite survivors via a telephone survey. Victims of rattlesnake bite who were treated at a single hospital center during a 10-year period were contacted through a telephone survey. Study subjects were included through a diagnosis-based retrospective chart review of snakebite victims, and excluded if they did not receive rattlesnake antivenom. Data collection was done using a standardized form that included sections about residual, recurrent, or new pain, weakness, paresthesias, or other limitations of the bitten limb. We identified 46 snakebite cases including 5 of 46 "dry" bites. The remaining cases (41 of 46) all received Crofab. Interviews were completed for 31% of these patients (13 of 41), and the remainder were lost to follow-up. Most bites occurred in men (12 cases, 92% males) and on the arms (9 cases, 69%). Six of the 13 respondents (46%) reported residual symptoms from the bite. Persistent symptoms described included localized pain at the bite site (3 cases), numbness or paresthesias (2 cases), abnormal skin peeling and discoloration at the bite site (2 cases), and persistent weakness of the bitten extremity (1 case). Among patients reporting persistent symptoms, the bite-to-survey interval ranged from 7 months to 12 years, with a median interval of 4 years. Our study population demonstrated a notable incidence (43%) of self-reported persistent symptoms related to their rattlesnake bites, although the overall level of disability from these injuries seems low. Copyright © 2014 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

To bite or not to bite! A questionnaire-based survey assessing why some people are bitten more than others by midges

PubMed Central

2010-01-01

Background The Scottish biting midge, Culicoides impunctatus, responsible for more than 90% of biting attacks on human beings in Scotland, is known to demonstrate a preference for certain human hosts over others. Methods In this study we used a questionnaire-based survey to assess the association between people's perception of how badly they get bitten by midges and their demographic, lifestyle and health related characteristics. Results Most people (85.8%) reported being bitten sometimes, often or always with only 14.2% reporting never being bitten by midges when in Scotland. There was no association between level of bites received and age, smoking, diet, exercise, medication, eating strongly flavoured foods or alcohol consumption. However, there was a strong association between the probability of being bitten and increasing height (in men) and BMI (in women). A large proportion of participants (33.8%) reported experiencing a bad/severe reaction to midge bites while 53.1% reported a minor reaction and 13.1% no reaction at all. Also, women tend to react more than men to midge bites. Additionally, the results indicated that the susceptibility to being bitten by midges is hereditary. Conclusions This study suggests that midges prefer to bite men that are tall and women that have a large BMI, and that the tendency for a child to be bitten or not could be inherited from their parent. The study is questionnaire-based; therefore, the interpretation of the results may be limited by the subjectivity of the answers given by the respondents. Although the results are relevant only to the Scottish biting midge, the approach used here could be useful for investigating human-insect interactions for other insects, particularly those which transmit pathogens that cause disease. PMID:20500852

Use of forensic analysis to better understand shark attack behaviour.

PubMed

Ritter, E; Levine, M

2004-12-01

Shark attacks have primarily been analyzed from wound patterns, with little knowledge of a shark's approach, behaviour and intention leading to such wounds. For the first time, during a shark-human interaction project in South Africa, a white shark, Carcharodon carcharias, was filmed biting a vertically positioned person at the water surface, and exhibiting distinct approach patterns leading to the bite. This bite was compared to ten white shark attacks that occurred (i) in the same geographical area of South Africa, and (ii) where the same body parts were bitten. Close similarity of some of these wound patterns to the bite imprint of the videotaped case indicate that the observed behaviour of the white shark may represent a common pattern of approaching and biting humans.

Multiple lesions by vampire bat bites in a patient in Niterói, Brazil - Case report*

PubMed Central

Bernardes, Fred; Martins, Gustavo; Luchi, Gustavo Sabaini; Kac, Bernard Kawa; Nery, José Augusto da Costa; Azulay-Abulafia, Luna; Azulay, David Rubem

2014-01-01

Over the last few centuries, the expansion of urbanization brought bats closer to urbanized areas, increasing the risk of accidents by bat bites. The morphology of bat bites can be varied, usually having an elliptical shape, about 0.5 cm along its greatest length, and the characteristic corkscrew bite pattern. The authors present the case of a patient who was repeatedly bitten by vampire bats for two months. A polymerase chain reaction was performed in the cutaneous nerves at the base of the hair follicles which showed negativity towards the rabies virus. The authors highlight the public health importance of this case, and discuss the morphological characteristics of these hematophagous bat bites. PMID:24770518

Effect of hypnosis on induction of local anaesthesia, pain perception, control of haemorrhage and anxiety during extraction of third molars: a case-control study.

PubMed

Abdeshahi, Seyyed Kazem; Hashemipour, Maryam Alsadat; Mesgarzadeh, Vahid; Shahidi Payam, Akbar; Halaj Monfared, Alireza

2013-06-01

Systemic conditions are considered limiting factors for surgical procedures under local anaesthesia in the oral cavity. All the pharmacological methods to control pain in patients have some disadvantages, such as side effects and extra costs for rehabilitation. Therefore, in such cases alternative treatment modalities are considered, such as hypnosis in dentistry. The aim of the present study was to evaluate the effect of hypnosis on haemorrhage, pain and anxiety during the extraction of third molars. In this case-control study, 24 female and male volunteers were included. The subjects had been referred to the Department of Oral and Maxillofacial Surgery, Kerman University of Medical Sciences, for extraction of third molars. Demographic data for all the subjects were recorded. Patients with chronic medical conditions were excluded. The patients were used as their own controls, with the third molars on one side being removed under hypnosis and on the opposite side under local anaesthetic. Hypnosis was induced by one of the two methods, either fixing the gaze on one point or Chiasson's technique; both these methods are appropriate for patients in the dental chair. The Spielberger State-Trait Anxiety Inventory was used to determine patient anxiety levels before hypnosis and anaesthesia. Pain was scored using VAS (visual analogue scale). After surgery the patient was asked to bite on a sterile gauze pad over the surgical site for 30 min when haemorrhage from the area was evaluated. If there was no haemorrhage the patient was discharged. If haemorrhage persisted, the gauze pad was left in place for another 30 min and the area was re-evaluated. Any active oozing from the area after 30 min was considered haemorrhage. Haemorrhage, anxiety and pain were compared between the two groups. Data was analyzed using the t-test, McNemar's test and Wilcoxon's signed rank test using SPSS 18 statistical software. Twenty-four patients were evaluated; there were 14 males (58.3%) and 10 females (41.7%). The mean age of the subjects was 24.1 ± 2.7 years (age range = 18-30 years). A total of 48 third molars were extracted. In each patient, one-third molar was extracted under hypnosis and the other under local anaesthesia. All the patients were in the ASA 1 category (normal) with no significant medical history. Of the subjects who underwent hypnosis, only two subjects (8.3%) reported pain after induction of hypnosis. In the local anaesthetic group, 8 subjects (33.3%) reported pain. There was a significant difference between the two groups. The results of the study showed that patients in the hypnosis group had less pain during the first few hours post-operatively. Anxiety scores in the two groups were very close to each other and no statistically significant differences were observed in general and when each person was compared with himself or herself. Pain intensity in the two groups at 5- and 12-h post-operatively exhibited significant differences. In the hypnosis group, 10 patients (41.7%) took analgesic medication; in the local anaesthesia group, 22 patients (91.7%) took the analgesic medication (P = 0.0001). In other words, patients reported less pain when they were under hypnosis. The results of the study showed that hypnosis can effectively reduce anxiety, haemorrhage and pain. More studies are necessary to collect data on the effect of hypnosis on oral and maxillofacial surgeries. Copyright © 2012 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Bullous reactions to bed bug bites reflect cutaneous vasculitis

USDA-ARS?s Scientific Manuscript database

This study evaluates bullous cutaneous reactions and sequential histopathology in an individual sensitized to bed bug bites in an effort to better understand the allergic response and histology associated with these bites. There was a progression of the inflammatory response across time ranging from...

Snake bite complicated by acute kidney injury secondary to necrotizing glomerulonephritis.

PubMed

Al Qahtani, Mohammad A; Altheaby, Abdulrahman; Al Anazi, T; Al Saad, Khaled; Binsalih, S; Al Helail, Mohammed

2014-11-01

We present a 38-year-old man who presented to the emergency department with complaints of a snake bite. He developed acute kidney injury (AKI) and the kidney biopsy showed necrotizing glomerulonephritis, which is rarely reported in AKI after snake bite.

Probability of Regenerating a Normal Limb After Bite Injury in the Mexican Axolotl (Ambystoma mexicanum).

PubMed

Thompson, Sierra; Muzinic, Laura; Muzinic, Christopher; Niemiller, Matthew L; Voss, S Randal

2014-06-01

Multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. We examined adult and juvenile axolotls ( Ambystoma mexicanum ) in the Ambystoma Genetic Stock Center (AGSC) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. We observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. Among 717 adult axolotls that were surveyed, which included solitary-housed males and group-housed females, approximately half presented abnormalities, including examples of extra or missing digits and limbs, fused digits, and digits growing from atypical anatomical positions. Bite injury likely explains these limb defects, and not abnormal development, because limbs with normal anatomy regenerated after performing rostral amputations. We infer that only 43% of AGSC larvae will present four anatomically normal looking adult limbs after incurring a bite injury. Our results show regeneration of normal limb anatomy to be less than perfect after bite injury.

Impact of a healthy nails program on nail-biting in Turkish schoolchildren: a controlled pretest-posttest study.

PubMed

Ergun, Ayse; Toprak, Rumeysa; Sisman, Fatma Nevin

2013-12-01

This study was conducted to examine the effect of a healthy nails program on nail-biting in Turkish schoolchildren. This quasi-experimental study was of pretest-posttest control group design. A total of 50 students of a primary school formed the intervention group, while 53 students from the same school formed the control group. Data were collected with a demographic form, a nail-biting follow-up form, and photographs of the fingernails. It was found that 68.9% of students were biting seven or more of their nails; 46.6% had damaged nail beds. In the intervention group, the rate of the children who were not biting their nails (baseline = 0%, 4th week = 56.0%, 8th week = 64.0%) increased significantly compared to the control group (baseline = 0%, 4th week = 15.1%, 8th week = 18.9%). Outcomes indicate the efficacy of the healthy nails program in reducing the nail-biting problem in schoolchildren.

Periocular dog bite injuries and responsible care.

PubMed

Burroughs, John R; Soparkar, Charles N S; Patrinely, James R; Williams, Patrick D; Holck, David E E

2002-11-01

To report patients who received dog bite injuries to the periocular area and the incidence of repeat attacks by the biting dog and its disposition. To discuss the demographics of bite attacks, occult injuries, steps to avoid medicolegal problems, and the appropriate options for animal disposition. Single-practice prospective case series of dog attacks on 18 victims. Patients were followed and questioned about any repeat attacks by the offending dog. Of 18 individuals who received dog bites to the perio-ocular area, only 2 were >12 years old. Of the 16 cases available for follow-up (4 months to 3 years; mean, 16 months), 7 of the dogs were euthanized and 1 was sent away from the family. Of the 8 remaining animals, 5 (63%) bit again. All the dogs bit family members or family friends. Although most dogs make wonderful pets, canine bites pose a significant public health concern, and some simple steps may be taken to protect against personal injury and legal fallout from repeat attacks.

Bite Injuries to the Hand - Review of the Literature

PubMed Central

Raval, Pradyumna; Khan, Wasim; Haddad, Behrooz; Mahapatra, Anant Narayan

2014-01-01

Patients presenting to the emergency department with bite injuries to the hand sustain them through a number of causes including domesticated as well as stray animal bites, and human bites commonly sustained as a result of violence. The nature of the injuries sustained can be very deceptive. A small tooth mark on the exterior can be a fulminant infection in the tissues deeper down. Tendon injuries, fractures of the metacarpals and phalanges and management of the wound are critical issues faced by a surgeon in dealing with such patients. Similarly the less common bite injuries to the hand, often with disastrous and sometimes fatal complications, do also present to the emergency department. A high incidence of suspicion is needed in dealing with these injuries effectively. In our article we discuss the common as well as uncommon causes of bite injuries to the hand and their management. In addition to reviewing the literature to ascertain the management of such injuries, we also discuss interesting and rare case reports. PMID:25097675

Pilot study assessing the effectiveness of long-lasting permethrin-impregnated clothing for the prevention of tick bites.

PubMed

Vaughn, Meagan F; Meshnick, Steven R

2011-07-01

Tick-borne diseases such as Lyme disease, Rocky Mountain spotted fever, and ehrlichiosis are a significant concern for many thousands of workers who have frequent and unavoidable exposure to tick-infested habitats. Many North Carolina state employees with outdoor occupations report multiple tick bites each year, indicating that existing tick preventive strategies may be underutilized or ineffective. Treatment of clothing with permethrin, a nontoxic chemical with insecticidal, knockdown, and repellent properties, is highly effective against ticks. However, most permethrin products must be reapplied after several washings to maintain insecticidal activity. Recently, a factory-based method for long-lasting permethrin impregnation of clothing has been developed by Insect Shield, Inc., that allows clothing to retain insecticidal activity for over 70 washes. A nonrandomized open label pilot study was conducted to determine the effectiveness of Insect Shield-treated clothing for the prevention of tick bites among 16 outdoor workers from the North Carolina Division of Water Quality under actual field conditions. Participants completed questionnaires at the start of follow-up (March, 2008) and at the end of follow-up (September, 2008), and tick bites and outdoor work hours were reported on weekly tick bite logs for the entire follow-up period. Subjects wearing Insect Shield-treated clothing had a 93% reduction (p < 0.0001) in the total incidence of tick bites compared to subjects using standard tick bite prevention measures. This study provides preliminary evidence that long-lasting permethrin-impregnated clothing may be highly effective against tick bites.

Two-year follow-up of changes in bite force and occlusal contact area after intraoral vertical ramus osteotomy with and without Le Fort I osteotomy.

PubMed

Choi, Y J; Lim, H; Chung, C J; Park, K H; Kim, K H

2014-06-01

This study was performed to examine the longitudinal changes in bite force and occlusal contact area after mandibular setback surgery via intraoral vertical ramus osteotomy (IVRO). Patients with mandibular prognathism who underwent IVRO (surgical group: 39 men and 39 women) were compared with subjects with class I skeletal and dental relationships (control group; 32 men and 35 women). The surgical group was divided into two subgroups: 1-jaw surgery (n = 30) and 2-jaw surgery (n = 48). Bite force and contact area were measured in maximum intercuspation with the Dental Prescale System before treatment, within 1 month before surgery, and at 1, 3, 6, 9, 12, and 24 months postsurgery. A linear mixed model was used to investigate the time-dependent changes and associated factors. Bite force and contact area decreased during presurgical orthodontic treatment, were minimal at 1 month postsurgery, and increased gradually thereafter. The 1-jaw and 2-jaw subgroups showed no significant differences in bite force. The time-dependent changes in bite force were significantly different according to the contact area (P < 0.05). The results of this study suggest that bite force and occlusal contact area gradually increase throughout the postsurgical evaluation period. Increasing the occlusal contact area may be essential for improving bite force after surgery. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Clinical Features and Outcomes of Pasteurella multocida Infection

PubMed Central

Giordano, Antonio; Dincman, Toros; Clyburn, Benjamin E.; Steed, Lisa L.; Rockey, Don C.

2015-01-01

Abstract Pasteurella multocida, a zoonotic infectious organism, has most often been described in patients after an animal bite. Here, we characterize the clinical features and outcomes of P multocida infection in a large cohort of patients according to the presence or absence of an animal bite. We retrospectively searched MUSC's laboratory information system for all patients with positive P multocida cultures from 2000 to 2014. Extensive data were abstracted, including clinical and outcome data. The Charlson comorbidity index (CCI) was used to assess comorbidities among patients. We identified 44 patients with P multocida infections, including 25 with an animal bite. The average age was 64 years and the majority of patients were women (N = 30). There was no difference in age and sex distribution among those with and without a bite (P = 0.38 and 0.75, respectively). A CCI ≥1 was significantly associated with the absence of a bite (P = 0.006). Patients presenting without a bite were more frequently bacteremic (37% vs 4%, respectively, P = 0.001), and were hospitalized more often (84% vs 44%, respectively, P = 0.012). Of the 8 patients who required intensive care unit (ICU)-based care, 7 were non-bite-related. There were 4 deaths, all occurring in patients not bitten. P multocida infections not associated with an animal bite were often associated with bacteremia, severe comorbidity(ies), immune-incompetent states, the need for ICU management, and were associated with substantial mortality. PMID:26356688

A cross-sectional study for predicting tail biting risk in pig farms using classification and regression tree analysis.

PubMed

Scollo, Annalisa; Gottardo, Flaviana; Contiero, Barbara; Edwards, Sandra A

2017-10-01

Tail biting in pigs has been an identified behavioural, welfare and economic problem for decades, and requires appropriate but sometimes difficult on-farm interventions. The aim of the paper is to introduce the Classification and Regression Tree (CRT) methodologies to develop a tool for prevention of acute tail biting lesions in pigs on-farm. A sample of 60 commercial farms rearing heavy pigs were involved; an on-farm visit and an interview with the farmer collected data on general management, herd health, disease prevention, climate control, feeding and production traits. Results suggest a value for the CRT analysis in managing the risk factors behind tail biting on a farm-specific level, showing 86.7% sensitivity for the Classification Tree and a correlation of 0.7 between observed and predicted prevalence of tail biting obtained with the Regression Tree. CRT analysis showed five main variables (stocking density, ammonia levels, number of pigs per stockman, type of floor and timeliness in feed supply) as critical predictors of acute tail biting lesions, which demonstrate different importance in different farms subgroups. The model might have reliable and practical applications for the support and implementation of tail biting prevention interventions, especially in case of subgroups of pigs with higher risk, helping farmers and veterinarians to assess the risk in their own farm and to manage their predisposing variables in order to reduce acute tail biting lesions. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of breastfeeding and sucking habits on malocclusion in a birth cohort study.

PubMed

Peres, Karen Glazer; Barros, Aluísio J D; Peres, Marco Aurélio; Victora, César Gomes

2007-06-01

To estimate the prevalence of malocclusion and to examine the effects of breastfeeding and non-nutritive sucking habits on dentition in six-year-old children. A cross-sectional study was carried out nested into a birth cohort conducted in Pelotas, Southern Brazil, in 1999. A sample of 359 children was dentally examined and their mothers interviewed. Anterior open bite and posterior cross bite were recorded using the Foster & Hamilton criteria. Information regarding breastfeeding and non-nutritive sucking habits was collected at birth, in the first, third, sixth and 12th months of life, and at six years of age. Control variables included maternal schooling and child's birthweight, cephalic perimeter, and sex. Data were analyzed by Poisson regression. Prevalence of anterior open bite was 46.2%, and that of posterior cross bite was 18.2%. Non-nutritive sucking habits between 12 months and four years of age and digital sucking at age six years were the main risk factors for anterior open bite. Breastfeeding for less than nine months and regular use of pacifier between age 12 months and four years were risk factors for posterior cross bite. Interaction between duration of breastfeeding and the use of pacifier was identified for posterior cross bite. Given that breastfeeding is a protective factor for other diseases of infancy, our findings indicate that the common risks approach is the most appropriate for the prevention of posterior cross bite in primary or initial mixed dentition.

Feeding biomechanics of the cownose ray, Rhinoptera bonasus, over ontogeny

PubMed Central

Kolmann, Matthew A; Huber, Daniel R; Motta, Philip J; Grubbs, R Dean

2015-01-01

Growth affects the performance of structure, so the pattern of growth must influence the role of a structure and an organism. Because animal performance is linked to morphological specialization, ontogenetic change in size may influence an organism's biological role. High bite force generation is presumably selected for in durophagous taxa. Therefore, these animals provide an excellent study system for investigating biomechanical consequences of growth on performance. An ontogenetic series of 27 cownose rays (Rhinoptera bonasus) were dissected in order to develop a biomechanical model of the feeding mechanism, which was then compared with bite forces measured from live rays. Mechanical advantage of the feeding apparatus was generally conserved throughout ontogeny, while an increase in the mass and cross-sectional area of the jaw adductors resulted in allometric gains in bite force generation. Of primary importance to forceful biting in this taxon is the use of a fibrocartilaginous tendon associated with the insertion of the primary jaw adductor division. This tendon may serve to redirect muscle forces anteriorly, transmitting them within the plane of biting. Measured bite forces obtained through electrostimulation of the jaw adductors in live rays were higher than predicted, possibly due to differences in specific tension of actual batoid muscle and that used in the model. Mass-specific bite forces in these rays are the highest recorded for elasmobranchs. Cownose rays exemplify a species that, through allometric growth of bite performance and morphological novelties, have expanded their ecological performance over ontogeny. PMID:26183820

Functional Analysis and Treatment of Nail Biting

ERIC Educational Resources Information Center

Dufrene, Brad A.; Watson, T. Steuart; Kazmerski, Jennifer S.

2008-01-01

This study applied functional analysis methodology to nail biting exhibited by a 24-year-old female graduate student. Results from the brief functional analysis indicated variability in nail biting across assessment conditions. Functional analysis data were then used to guide treatment development and implementation. Treatment included a…

Function-dependent shape characteristics of the human skull.

PubMed

Witzel, U; Preuschoft, H

2002-06-01

Using the FEM-program ANSYS 5.4, we have shaped a model of the human skull in which the flow of forces and the relative location and magnitudes of stresses are investigated. Forces are applied from below through the tooth row of the upper jaw. An ample volume is provided for the transmission of these bite forces upward to the roof of the braincase, where bearings counteract the forces from below. Within this volume, no other morphological features are considered than two cone-shaped orbits and a nasal channel which has a rounded, triangular cross section, extending upward between the orbits. Under loads (= bite forces) acting simultaneously in the directions and relative sizes of realistic bite- and chewing forces, there occurred stress concentrations inside the model which resemble closely the morphological characteristics of the human skull. The most remarkable pathways of stresses correspond to Toldt's and Benninghoff's nasal, zygomatic and pterygoid pillars. Aside from these stress concentrations, stress-free regions become visible at places, where the skull shows excavations: the vaulted palate with canalis incisivus, the canine fossa, superior and inferior orbital fissure, or cavities like the maxillary sinuses and cavum cranii. Behind the posterior molars and the pterygoid, the stresses disappear abruptly, and in the side wall of the nasal cavity a maxillary hiatus remains without stresses. A flow of forces comparable to, but not at the exact position of the zygomatic arch extends from the highly stressed zygomatic bone rearward and upward. In a later step of simulation, somewhat deeper, at the place of the really existing zygomatic arch, a series of small forces was applied, which correspond to the resultant force that is created by the redirection of the pull of the m. masseter into the temporal fascia. This--biologically reasonable--manipulation of the model leads to a reduction of the forces in the zygomatic bone, and to a downward shift of the zygomatic arch and its isolation from the skull's side wall by a deep, stress-free temporal fossa. The similarity between the stress flow in the model and the shape of the skull seems to indicate that the skull, like the bones of the postcranial skeleton, develops its shape in dependence from the mechanic stressing through the process of causal histogenesis. In view of experimental results, the possibility cannot be ruled out, that the safety factors in the skull deviate from those in the postcranial skeleton.

Development of botanical-based biopesticides and repellents against biting flies on livestock animals

USDA-ARS?s Scientific Manuscript database

Biting flies are important insect pests causing millions of dollars in losses to the livestock industry. The attack by biting flies causes significant losses in animal production and potential food contamination and disease transmission. This presentation reports our recent findings on the developme...

An Innovative Miniature Bite Force Recorder

PubMed Central

Utreja, Ashok K; Sandhu, Navreet; Dhaliwal, Yadvinder S

2011-01-01

In this study, a detailed description of development of a new novel bite force recorder (gnathodynamometer) using solid state components is vividly explained. This state of the art authenticated device can be used to assess the complex function of human bite force, which is the net resultant combination of functional response of various craniomandibular structures consisting of interrelated components, like the muscles of mastication, joints, teeth and the neuromuscular system. The consistency and accuracy of the bite force recorder was reaffirmed by doing a detailed laboratory calibration and clinical testing on 30 adult subjects. PMID:27672249

A case of Tinea nigra associated to a bite from a European rabbit (Oryctolagus cuniculus, Leporidae): the role of dermoscopy in diagnosis.

PubMed

Rossetto, André Luiz; Corrêa, Patricia Rossetto; Cruz, Rosana Cé Bella; Pereira, Eduardo Figueiredo; Haddad Filho, Vidal

2014-01-01

We report a case of Tinea nigra in an adolescent living in Itapema, Santa Catarina, Brazil, who presented a hyperchromic macule on the palm of the left hand, close to another erythematous macule caused by a rabbit bite. The patient received guidance on accidents and animal bites and evolved well treated with topical butenafine for the dermatomycosis. The authors also highlight the efficacy of the dermoscopic exam in diagnosing Tinea nigra with animal bite lesions and other traumas.

A case of Tinea nigra associated to a bite from a European rabbit (Oryctolagus cuniculus, Leporidae): the role of dermoscopy in diagnosis*

PubMed Central

Rossetto, André Luiz; Corrêa, Patricia Rossetto; Cruz, Rosana Cé Bella; Pereira, Eduardo Figueiredo; Haddad Junior, Vidal

2014-01-01

We report a case of Tinea nigra in an adolescent living in Itapema, Santa Catarina, Brazil, who presented a hyperchromic macule on the palm of the left hand, close to another erythematous macule caused by a rabbit bite. The patient received guidance on accidents and animal bites and evolved well treated with topical butenafine for the dermatomycosis. The authors also highlight the efficacy of the dermoscopic exam in diagnosing Tinea nigra with animal bite lesions and other traumas. PMID:24626667

Breaking the Thumb Sucking Habit: When Compliance Is Essential

PubMed Central

Tanaka, Orlando; Oliveira, Wagner; Galarza, Melissa; Aoki, Vanessa; Bertaiolli, Bruno

2016-01-01

The anterior open bite (AOB) and posterior cross bite are the most frequent malocclusions associated with prolonged sucking habits. This clinical case illustrates and discusses the use of a Haas-type palatal expander for stopping a thumb sucking habit. The improvement in closing the open bite with discontinuation of the habit was observed. But with the return of the habit and lack of cooperation, the relapse of anterior open bite occurred. Therefore, different approaches are necessary. The need of a multidisciplinary approach, consent, and cooperation are keys to a good prognosis. PMID:26904311

Sensitivity to bites by the bedbug, Cimex lectularius.

PubMed

Reinhardt, K; Kempke, D; Naylor, R A; Siva-Jothy, M T

2009-06-01

Bedbugs are a public health problem and can cause significant economic losses, but little is known about the effects of bites on humans. We reviewed case reports and published papers on bedbug bites to assess the empirical basis of the commonly cited figure that only approximately 80% of the population are sensitive to bedbug bites. We found the sensitivity estimate to be based on only one study carried out 80 years ago. However, this study did not account for the now well-established fact that only repeated exposure to external allergens leads to skin reactions. In our sample, 18 of 19 persons showed a skin reaction after bedbug exposure, but in most cases only after repeated controlled exposure. With repeated exposure, the latency between bite and skin reactions decreased from approximately 10 days to a few seconds. Our results are relevant for the hospitality industry, where apparently increasing infestation rates are likely to lead to an increase in the number of tourists and hotel employees exposed to bedbugs. Medical and public health professionals may expect to see an increase in the prevalence of people with bedbug bite sensitivity. The significance of the delayed reaction time of skin to bites may also have implications in litigation cases where people seek compensation.

Tick-host conflict: immunoglobulin E antibodies to tick proteins in patients with anaphylaxis to tick bite

PubMed Central

Mateos-Hernández, Lourdes; Villar, Margarita; Moral, Angel; GarcíaRodríguez, Carmen; Arias, Teresa Alfaya; de la Osa, Verónica; Brito, Francisco Feo; Fernández de Mera, Isabel G.; Alberdi, Pilar; Ruiz-Fons, Francisco; Cabezas-Cruz, Alejandro; Estrada-Peña, Agustín; de la Fuente, José

2017-01-01

Tick-borne infectious diseases and allergies are a growing problem worldwide. Tick bite allergy has been associated with the direct effect of immunoglobulin E (IgE) response to tick salivary antigens, or secondary to the induction of allergy to red meat consumption through IgE antibodies against the carbohydrate α-Gal (Gal α 1-3Gal β 1-(3)4GlcNAc-R). However, despite the growing burden of this pathology, the proteins associated with anaphylaxis to tick bite have not been characterized. To address this question, a comparative proteomics approach was used to characterize tick proteins producing an IgE antibody response in a healthy individual with record of tick bites, which had not resulted in any allergic reactions, and two patients with anaphylactic reactions to Rhipicephalus bursa or Hyalomma marginatum tick bites. Both patients and the healthy individual were red meat tolerant. The results supported a patient-specific IgE antibody response to tick species responsible for the anaphylaxis to tick bite. Both patients and the healthy individual serologically recognized tick proteins with and without α-Gal modifications, with proteins differentially recognized by patients but not control sera. These proteins could be used as potential antigens for diagnostics, treatment and prevention of tick bite-induced allergies. PMID:28423486

Development of a polymerase chain reaction to distinguish monocellate cobra (Naja khouthia) bites from other common Thai snake species, using both venom extracts and bite-site swabs.

PubMed

Suntrarachun, S; Pakmanee, N; Tirawatnapong, T; Chanhome, L; Sitprija, V

2001-07-01

A PCR technique was used in this study to identify and distinguish monocellate cobra snake bites using snake venoms and swab specimens from snake bite-sites in mice from bites by other common Thai snakes. The sequences of nucleotide primers were selected for the cobrotoxin-encoding gene from the Chinese cobra (Naja atra) since the sequences of monocellate cobra (Naja kaouthia) venom are still unknown. However, the 113-bp fragment of cDNA of the cobrotoxin-encoding gene was detected in the monocellate cobra venom using RT-PCR. This gene was not found in the venoms of Ophiophagus hannah (king cobra), Bungarus fasciatus (banded krait), Daboia russelii siamensis (Siamese Russell's Viper, and Calloselasma rhodostoma (Malayan pit viper). Moreover, direct PCR could detect a 665-bp fragment of the cobrotoxin-encoding gene in the monocellate cobra venom but not the other snake venoms. Likewise, this gene was only observed in swab specimens from cobra snake bite-sites in mice. This is the first report demonstrating the ability of PCR to detect the cobrotoxin-encoding gene from snake venoms and swab specimens. Further studies are required for identification of this and other snakes from the bite-sites on human skin.

The management of animal bites in the United kingdom.

PubMed

Evgeniou, E; Markeson, D; Iyer, S; Armstrong, A

2013-01-01

Animal bites represent a significant global health issue. The evidence in the literature regarding their management in many areas is conflicting and unclear. This project attempts to identify current evidence in the literature on the management of animal bites and assess if current practice in the United Kingdom is evidence based. A literature review on the management of animal bites was performed, and a national UK survey was contacted using a questionnaire based on the available evidence in the literature. The results from this survey show that 98% of plastic surgery units routinely use prophylactic antibiotics in all animal bite wounds; 58% close low-risk injuries primarily after initial washout, and there are conflicting opinions regarding the management of associated fractures and soft tissue injuries. The available data in the literature suggest that appropriate wound management is the most important factor for prevention of infection in animal bites. Antibiotic prophylaxis should only be given in high-risk wounds and primary closure should be performed in low-risk wounds. The management protocols of many plastic surgery units often diverge from the available evidence within the literature. On the basis of a thorough literature review, a guideline for the management of animal bites is presented. Future studies should investigate the management of associated fractures and soft tissue injuries.

Decrease in tick bite consultations and stabilization of early Lyme borreliosis in the Netherlands in 2014 after 15 years of continuous increase.

PubMed

Hofhuis, Agnetha; Bennema, Sita; Harms, Margriet; van Vliet, Arnold J H; Takken, Willem; van den Wijngaard, Cees C; van Pelt, Wilfrid

2016-05-23

Nationwide surveys have shown a threefold increase in general practitioner (GP) consultations for tick bites and early Lyme borreliosis from 1994 to 2009 in the Netherlands. We now report an update on 2014, with identical methods as for the preceding GP surveys. To all GPs in the Netherlands, a postal questionnaire was sent inquiring about the number of consultations for tick bites and erythema migrans diagnoses (most common manifestation of early Lyme borreliosis) in 2014, and the size of their practice populations. Contrasting to the previously rising incidence of consultations for tick bites between 1994 and 2009, the incidence decreased in 2014 to 488 consultations for tick bites per 100,000 inhabitants, i.e., 82,000 patients nationwide. This survey revealed a first sign of stabilization of the previously rising trend in GP diagnosed erythema migrans, with 140 diagnoses per 100,000 inhabitants of the Netherlands. This equals about 23,500 annual diagnoses of erythema migrans nationwide in 2014. In contrast to the constantly rising incidence of GP consultations for tick bites and erythema migrans diagnoses in the Netherlands between 1994 and 2009, the current survey of 2014 showed a first sign of stabilization of erythema migrans diagnoses and a decreased incidence for tick bite consultations.

Factors Associated With Bites to a Child From a Dog Living in the Same Home: A Bi-National Comparison

PubMed Central

Messam, Locksley L. McV.; Kass, Philip H.; Chomel, Bruno B.; Hart, Lynette A.

2018-01-01

We conducted a veterinary clinic-based retrospective cohort study aimed at identifying child-, dog-, and home-environment factors associated with dog bites to children aged 5–15 years old living in the same home as a dog in Kingston, Jamaica (236) and San Francisco, USA (61). Secondarily, we wished to compare these factors to risk factors for dog bites to the general public. Participant information was collected via interviewer-administered questionnaire using proxy respondents. Data were analyzed using log-binomial regression to estimate relative risks and associated 95% confidence intervals (CIs) for each exposure–dog bite relationship. Exploiting the correspondence between X% confidence intervals and X% Bayesian probability intervals obtained using a uniform prior distribution, for each exposure, we calculated probabilities of the true (population) RRs ≥ 1.25 or ≤0.8, for positive or negative associations, respectively. Boys and younger children were at higher risk for bites, than girls and older children, respectively. Dogs living in a home with no yard space were at an elevated risk (RR = 2.97; 95% CI: 1.06–8.33) of biting a child living in the same home, compared to dogs that had yard space. Dogs routinely allowed inside for some portion of the day (RR = 3.00; 95% CI: 0.94–9.62) and dogs routinely allowed to sleep in a family member’s bedroom (RR = 2.82; 95% CI: 1.17–6.81) were also more likely to bite a child living in the home than those that were not. In San Francisco, but less so in Kingston, bites were inversely associated with the number of children in the home. While in Kingston, but not in San Francisco, smaller breeds and dogs obtained for companionship were at higher risk for biting than larger breeds and dogs obtained for protection, respectively. Overall, for most exposures, the observed associations were consistent with population RRs of practical importance (i.e., RRs ≥ 1.25 or ≤0.8). Finally, we found substantial consistency between risk factors for bites to children and previously reported risk factors for general bites. PMID:29780810

Gradient Drift Turbulence from Electron Bite-Outs: Dependence on Atmospheric Parameters.

NASA Astrophysics Data System (ADS)

Young, M.; Oppenheim, M. M.; Dimant, Y. S.

2017-12-01

Electron bite-outs are regions of decreased electron density without a corresponding decrease in ion density, often caused by electron attachment to dust grains. They typically occur in the upper D-/lower E-region ionosphere and the accompanying electron gradient provides free energy to drive the gradient drift instability (GDI). The major difference between classical GDI and electron bite-out driven GDI is that the instability occurs on the top side of the bite-out region in the latter, as opposed to the bottom side in the former, in the presence of a vertical background electric field. Moreover, the mobile plasma population contains a gradient in only one species while the entire system remains quasineutral. This modified geometry presents new pathways for instabilities as the ions build up near the bite-out layer, leaving behind depletions that ascend away from the layer. Previous simulation runs showed that the presence of an electron gradient drives GDI-like turbulence even when ions and electrons start in momentum balance. Furthermore, a simulation run that replaced the electron bite-out with a layer of enhanced ion density, as though ions and electrons had filled in the bite-out region, did not lead to instability. This work examines the role of atmospheric parameters at altitudes between 80-100 km in instability formation and turbulence development, including the role of collisions in impeding instability growth as altitude decreases. Key parameters include the ambient electric field, which plays a critical role in triggering the gradient-drift instability; collision frequencies and temperature, which vary with altitude and effect the turbulent growth rate; and relative charge density of the bite-out, which increases the electron gradient strength. This work provides insight into how electron bite-out layers can produce turbulence that ground-based high frequency (HF) radars may be able to observe. The upper D-/lower E-region ionosphere is generally difficult to study in situ, making simulations of ground-based observables much more important. Assuming that electron bite-out layers result from dust charging in particular will allow the community to use the predictions of this work to study the ionospheric dust population.

Water vapour and heat combine to elicit biting and biting persistence in tsetse

PubMed Central

2013-01-01

Background Tsetse flies are obligatory blood feeders, accessing capillaries by piercing the skin of their hosts with the haustellum to suck blood. However, this behaviour presents a considerable risk as landing flies are exposed to predators as well as the host’s own defense reactions such as tail flicking. Achieving a successful blood meal within the shortest time span is therefore at a premium in tsetse, so feeding until replete normally lasts less than a minute. Biting in blood sucking insects is a multi-sensory response involving a range of physical and chemical stimuli. Here we investigated the role of heat and humidity emitted from host skin on the biting responses of Glossina pallidipes, which to our knowledge has not been fully studied in tsetse before. Methods The onset and duration of the biting response of G. pallidipes was recorded by filming movements of its haustellum in response to rapid increases in temperature and/or relative humidity (RH) following exposure of the fly to two airflows. The electrophysiological responses of hygroreceptor cells in wall-pore sensilla on the palps of G. pallidipes to drops in RH were recorded using tungsten electrodes and the ultra-structure of these sensory cells was studied by scanning and transmission electron microscopy. Results Both latency and proportion of tsetse biting are closely correlated to RH when accompanied by an increase of 13.1°C above ambient temperature but not for an increase of just 0.2°C. Biting persistence, as measured by the number of bites and the time spent biting, also increases with increasing RH accompanied by a 13.1°C increase in air temperature. Neurones in wall-pore sensilla on the palps respond to shifts in RH. Conclusions Our results show that temperature acts synergistically with humidity to increase the rapidity and frequency of the biting response in tsetse above the levels induced by increasing temperature or humidity separately. Palp sensilla housing hygroreceptor cells, described here for the first time in tsetse, are involved in the perception of differences in RH. PMID:23958224

Long-lasting permethrin impregnated uniforms: A randomized-controlled trial for tick bite prevention.

PubMed

Vaughn, Meagan F; Funkhouser, Sheana Whelan; Lin, Feng-Chang; Fine, Jason; Juliano, Jonathan J; Apperson, Charles S; Meshnick, Steven R

2014-05-01

Because of frequent exposure to tick habitats, outdoor workers are at high risk for tick-borne diseases. Adherence to National Institute for Occupational Safety and Health-recommended tick bite prevention methods is poor. A factory-based method for permethrin impregnation of clothing that provides long-lasting insecticidal and repellent activity is commercially available, and studies are needed to assess the long-term effectiveness of this clothing under field conditions. To evaluate the protective effectiveness of long-lasting permethrin impregnated uniforms among a cohort of North Carolina outdoor workers. A double-blind RCT was conducted between March 2011 and September 2012. Subjects included outdoor workers from North Carolina State Divisions of Forestry, Parks and Recreation, and Wildlife who worked in eastern or central North Carolina. A total of 159 volunteer subjects were randomized, and 127 and 101 subjects completed the first and second years of follow-up, respectively. Uniforms of participants in the treatment group were factory-impregnated with long-lasting permethrin whereas control group uniforms received a sham treatment. Participants continued to engage in their usual tick bite prevention activities. Incidence of work-related tick bites reported on weekly tick bite logs. Study subjects reported 1,045 work-related tick bites over 5,251 person-weeks of follow-up. The mean number of reported tick bites in the year prior to enrollment was similar for both the treatment and control groups, but markedly different during the study period. In our analysis conducted in 2013, the effectiveness of long-lasting permethrin impregnated uniforms for the prevention of work-related tick bites was 0.82 (95% CI=0.66, 0.91) and 0.34 (95% CI=-0.67, 0.74) for the first and second years of follow-up. These results indicate that long-lasting permethrin impregnated uniforms are highly effective for at least 1 year in deterring tick bites in the context of typical tick bite prevention measures employed by outdoor workers. Copyright © 2014 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

The "Smart Dining Table": Automatic Behavioral Tracking of a Meal with a Multi-Touch-Computer.

PubMed

Manton, Sean; Magerowski, Greta; Patriarca, Laura; Alonso-Alonso, Miguel

2016-01-01

Studying how humans eat in the context of a meal is important to understanding basic mechanisms of food intake regulation and can help develop new interventions for the promotion of healthy eating and prevention of obesity and eating disorders. While there are a number of methodologies available for behavioral evaluation of a meal, there is a need for new tools that can simplify data collection through automatic and online analysis. Also, there are currently no methods that leverage technology to add a dimension of interactivity to the meal table. In this study, we examined the feasibility of a new technology for automatic detection and classification of bites during a laboratory meal. We used a SUR40 multi-touch tabletop computer, powered by an infrared camera behind the screen. Tags were attached to three plates, allowing their positions to be tracked, and the saturation (a measure of the infrared intensity) in the surrounding region was measured. A Kinect camera was used to record the meals for manual verification and provide gesture detection for when the bites were taken. Bite detections triggered classification of the source plate by the SUR40 based on saturation flux in the preceding time window. Five healthy subjects (aged 20-40 years, one female) were tested, providing a total sample of 320 bites. Sensitivity, defined as the number of correctly detected bites out of the number of actual bites, was 67.5%. Classification accuracy, defined as the number of correctly classified bites out of those detected, was 82.4%. Due to the poor sensitivity, a second experiment was designed using a single plate and a Myo armband containing a nine-axis accelerometer as an alternative method for bite detection. The same subjects were tested (sample: 195 bites). Using a simple threshold on the pitch reading of the magnetometer, the Myo data achieved 86.1% sensitivity vs. 60.5% with the Kinect. Further, the precision of positive predictive value was 72.1% for the Myo vs. 42.8% for the Kinect. We conclude that the SUR40 + Myo combination is feasible for automatic detection and classification of bites with adequate accuracy for a range of applications.

Drivers of Daily Routines in an Ectothermic Marine Predator: Hunt Warm, Rest Warmer?

PubMed Central

Papastamatiou, Yannis P.; Watanabe, Yuuki Y.; Bradley, Darcy; Dee, Laura E.; Weng, Kevin; Lowe, Christopher G.; Caselle, Jennifer E.

2015-01-01

Animal daily routines represent a compromise between maximizing foraging success and optimizing physiological performance, while minimizing the risk of predation. For ectothermic predators, ambient temperature may also influence daily routines through its effects on physiological performance. Temperatures can fluctuate significantly over the diel cycle and ectotherms may synchronize behaviour to match thermal regimes in order to optimize fitness. We used bio-logging to quantify activity and body temperature of blacktip reef sharks (Carcharhinus melanopterus) at a tropical atoll. Behavioural observations were used to concurrently measure bite rates in herbivorous reef fishes, as an index of activity for potential diurnal prey. Sharks showed early evening peaks in activity, particularly during ebbing high tides, while body temperatures peaked several hours prior to the period of maximal activity. Herbivores also displayed peaks in activity several hours earlier than the peaks in shark activity. Sharks appeared to be least active while their body temperatures were highest and most active while temperatures were cooling, although we hypothesize that due to thermal inertia they were still warmer than their smaller prey during this period. Sharks may be most active during early evening periods as they have a sensory advantage under low light conditions and/or a thermal advantage over cooler prey. Sharks swam into shallow water during daytime low tide periods potentially to warm up and increase rates of digestion before the nocturnal activity period, which may be a strategy to maximize ingestion rates. “Hunt warm, rest warmer” may help explain the early evening activity seen in other ectothermic predators. PMID:26061229

Management of pediatric snake bites: are we doing too much?

PubMed

Correa, Jesus A; Fallon, Sara C; Cruz, Andrea T; Grawe, Glenda H; Vu, Phong V; Rubalcava, Daniel M; Kaziny, Brent; Naik-Mathuria, Bindi J; Brandt, Mary L

2014-06-01

The optimal management of children with snake bite injuries is not well defined. The purpose of this study was to review the use of antivenom, diagnostic tests, and antibiotics in children bitten by venomous snakes in a specific geographic region (Southeast Texas). This is a retrospective single-center review of all patients with snake bite injury from 1/2006 to 6/2012. An envenomated bite was defined as causing edema, discoloration of the skin, necrosis, or systemic effects. The severity of injury was scored using a novel 4-point scale based on initial physical examination alone. One hundred fifty-one children (mean age 8.4±4.3years) were treated for a snake bite. There were no mortalities. Lower extremity injuries were most common (60%). Most bites were from copperheads (43%). Envenomation was evident in 82% (average wound score: 2.61±0.81). The median hospital stay for admitted patients (79%) was 2days (range 1-7). Four patients required surgery for complications of the snake bite. Fifty-two children (34%) received CroFab, with one allergic reaction. 22/135 (16%) had evidence of coagulopathy. Seventy-two children (48%) received IV antibiotics. Despite a high rate of envenomated bites in Southeast Texas, significant morbidity is rare. Children with an envenomation score of 1 or 2 are unlikely to be coagulopathic, suggesting that laboratory investigation should be reserved for patients with higher scores. The indications for the administration of CroFab deserve further prospective study. Copyright © 2014 Elsevier Inc. All rights reserved.

Management of Tissue Loss After Agkistrodon Snakebite: Appropriate Use of Crotalidae-Fab Antivenin.

PubMed

Larson, Kenneth W; Schaefer, Keith R; Austin, Cindy; Norton, Rhy; Finley, Phillip J

2016-01-01

Although initially created for the treatment of rattlesnake (genus: Crotalus) bites, Crotalidae-Fab antivenin is used to treat many different pit viper envenomations. However, the efficacy of Crotalidae-Fab in preventing tissue loss from copperhead (Agkistrodon contortrix) or cottonmouth (Agkistrodon piscivorus) snakebites remains unclear. Recent reports show that Agkistrodon-related bites rarely require treatment beyond simple observation and pain control. The purpose of this study was to examine the amount of tissue loss in patients who received Crotalidae-Fab compared with those who did not after an Agkistrodon bite. After institutional review board approval, a retrospective study was completed at a Level 1 trauma center. Between 2009 and 2013, a total of 57 snakebites were identified. Of the 57 bites, the snake species was documented in 36 cases including 31 copperheads, 1 cottonmouth, and 4 rattlesnakes. The other 21 bites were from unknown or nonvenomous species. Of the 32 Agkistrodon-related bites, 15 patients received Crotalidae-Fab (average of 3 vials administered) and 17 did not receive Crotalidae-Fab. None of the 32 patients, regardless of treatment option, had tissue loss or required surgical interventions. Only 1 patient received Crotalidae-Fab and debridement of a vesicle associated with the bite. No clinically significant differences were observed between the groups. These findings support previous literature that failed to show added benefit of Crotalidae-Fab treatment for Agkistrodon bites beyond patient comfort and pain control. Evaluation of current protocols for Agkistrodon envenomations is warranted. Snakebite wound education in trauma physicians and nurses may decrease unnecessary use of antivenom medication.

Assessing the Accuracy of a Wrist Motion Tracking Method for Counting Bites across Demographic and Food Variables

PubMed Central

Shen, Yiru; Salley, James; Muth, Eric; Hoover, Adam

2017-01-01

This paper describes a study to test the accuracy of a method that tracks wrist motion during eating to detect and count bites. The purpose was to assess its accuracy across demographic (age, gender, ethnicity) and bite (utensil, container, hand used, food type) variables. Data were collected in a cafeteria under normal eating conditions. A total of 271 participants ate a single meal while wearing a watch-like device to track their wrist motion. Video was simultaneously recorded of each participant and subsequently reviewed to determine the ground truth times of bites. Bite times were operationally defined as the moment when food or beverage was placed into the mouth. Food and beverage choices were not scripted or restricted. Participants were seated in groups of 2–4 and were encouraged to eat naturally. A total of 24,088 bites of 374 different food and beverage items were consumed. Overall the method for automatically detecting bites had a sensitivity of 75% with a positive predictive value of 89%. A range of 62–86% sensitivity was found across demographic variables, with slower eating rates trending towards higher sensitivity. Variations in sensitivity due to food type showed a modest correlation with the total wrist motion during the bite, possibly due to an increase in head-towards-plate motion and decrease in hand-towards-mouth motion for some food types. Overall, the findings provide the largest evidence to date that the method produces a reliable automated measure of intake during unrestricted eating. PMID:28113994

Frameless stereotactic radiosurgery with a bite-plate: our experience with brain metastases.

PubMed

Furuse, M; Aoki, T; Takagi, T; Takahashi, J A; Ishikawa, M

2008-12-01

Non-invasive frameless stereotactic radiosurgical systems have recently been developed. We report our experience of frameless stereotactic radiosurgery (SRS) with a bite-plate for brain metastases. Between February 2002 and December 2005, 147 patients with brain metastases were treated with C-arm linear accelerator-based SRS and 122 patients were followed up by our institute. An optic tracking system with infrared light-emitting diodes was used for real-time monitoring. A bite-plate with fiducial markers was applied as a first-line method for frameless SRS. Head-ring fixation was used in patients lacking teeth. Lung carcinomas (63%) were the most common primary tumors, followed by breast carcinomas (13%). Ninety patients underwent radiosurgery with a bite-plate and 32 patients underwent fixation of a head ring. Males were significantly more predominant in the head-ring group (26 men and 6 women), compared with the bite-plate group (47 men and 43 women, p < 0.01). The average age (62 years) in the bite-plate group was significantly younger than that (68 years) in the head-ring group (p < 0.01). The median survival time was 12.0 months in the bite-plate group and 8.0 months in the head-ring group (p = 0.0621). Nine patients who had brain metastases in or close to the brain stem were treated with fractionated stereotactic radiotherapy. The frameless stereotactic radiosurgical system with a bite-plate is safe and effective for the treatment of brain metastasis. Elderly male patients sometimes are edentulous and require placement of a head ring for radiosurgery.

Insects and Bugs

ERIC Educational Resources Information Center

Sutherland, Karen

2009-01-01

They have been around for centuries. They sting, they bite. They cause intense itching or painful sores. They even cause allergic reactions and sometimes death. There are two types of insects that are pests to humans--those that sting and those that bite. The insects that bite do so with their mouths and include mosquitoes, chiggers, and ticks.…

Update on treated fabrics for control of biting fly species around livestock in sub-Saharan Africa

USDA-ARS?s Scientific Manuscript database

Treated fabrics can be used as an intervention on small livestock farms to prevent the entry of biting flies, thus reducing the incidence of disease transmission. The major objective is to prevent host-vector/biting fly contact. An efficacious barrier of treated fabric should significantly reduce or...

Probability of regenerating a normal limb after bite injury in the Mexican axolotl (Ambystoma mexicanum)

PubMed Central

Thompson, Sierra; Muzinic, Laura; Muzinic, Christopher; Niemiller, Matthew L.

2014-01-01

Abstract Multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. We examined adult and juvenile axolotls (Ambystoma mexicanum) in the Ambystoma Genetic Stock Center (AGSC) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. We observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. Among 717 adult axolotls that were surveyed, which included solitary‐housed males and group‐housed females, approximately half presented abnormalities, including examples of extra or missing digits and limbs, fused digits, and digits growing from atypical anatomical positions. Bite injury probably explains these limb defects, and not abnormal development, because limbs with normal anatomy regenerated after performing rostral amputations. We infer that only 43% of AGSC larvae will present four anatomically normal looking adult limbs after incurring a bite injury. Our results show regeneration of normal limb anatomy to be less than perfect after bite injury. PMID:25745564

Indirect genetic effects for growth rate in domestic pigs alter aggressive and manipulative biting behaviour.

PubMed

Camerlink, Irene; Ursinus, Winanda W; Bijma, Piter; Kemp, Bas; Bolhuis, J Elizabeth

2015-01-01

Indirect genetic effects (IGEs) are heritable effects of an individual on phenotypic values of others, and may result from social interactions. We determined the behavioural consequences of selection for IGEs for growth (IGEg) in pigs in a G × E treatment design. Pigs (n = 480) were selected for high versus low IGEg with a contrast of 14 g average daily gain and were housed in either barren or straw-enriched pens (n = 80). High IGEg pigs showed from 8 to 23 weeks age 40% less aggressive biting (P = 0.006), 27% less ear biting (P = 0.03), and 40% less biting on enrichment material (P = 0.005). High IGEg pigs had a lower tail damage score (high 2.0; low 2.2; P = 0.004), and consumed 30 % less jute sacks (P = 0.002). Selection on high IGEg reduced biting behaviours additive to the, generally much larger, effects of straw-bedding (P < 0.01), with no G × E interactions. These results show opportunities to reduce harmful biting behaviours in pigs.

Efficacy of topical permethrin as repellent against Aedes aegypti's bites.

PubMed

Miot, Hélio Amante; Ferreira, Daniela Pinho; Mendes, Fabiana Guandalini; Carrenho, Flávia Roberta Hernandes; de Oliveira Amui, Isabela; Carneiro, Carlos Augusto Sá; Madeira, Newton Goulart

2008-07-15

Mosquitoes are the most important vectors of infectious diseases and their bites are related to several adverse skin reactions. Permethrin impregnated clothes are an efficient strategy against arthropods' bites; however, its topical efficacy as a repellent has not been well established. We studied the response to permethrin lotion 5 percent and N,N-Diethyl-meta-toluamide (DEET) spray 50 percent applied to the unprotected forearms of 10 volunteers. Each arm was exposed to 20 female mosquitoes of Aedes aegypti. We performed 71 bilateral comparative measurements evaluating the timing for the first bites. The average times for the arm without the product, with permethrin 5 percent, and with DEET 50 percent were: 7.9 seconds, 336.2 seconds and 7512.1 seconds. The results showed a significant difference between repellency times between either product and unprotected controls. In addition, there was a significant difference in time to first bite between permethrin and DEET treated arms (p<0.01). Permethrin affords some repellent activity against Aedes aegypti bites in this experimental setting. However, permethrin's profile of repellency was significantly inferior to that of DEET.

Mosquito bite anaphylaxis: immunotherapy with whole body extracts.

PubMed

McCormack, D R; Salata, K F; Hershey, J N; Carpenter, G B; Engler, R J

1995-01-01

Adverse reactions to mosquito bites have been recognized for some time. These usually consist of large local swellings and redness, generalized urticaria, angioedema and less easily definable responses such as nausea, dizziness, headaches, and lethargy. We report two patients who experienced systemic anaphylaxis from mosquito bites. Both were skin tested and given immunotherapy using whole body mosquito extracts. Skin testing using whole body mosquito extracts was positive to Aedes aegypti at 1/1,000 weight/volume (wt/vol) in one patient and to Aedes aegypti at 1/100,000 wt/vol, and Culex pipiens at 1/10,000 wt/vol in the other. Skin testing of ten volunteers without a history of adverse reactions to mosquito bites was negative. Immunotherapy using these extracts resulted in resolution of adverse reactions to mosquito bites in one patient and a decrease in reactions in the other. Immunotherapy with whole body mosquito extracts is a viable treatment option that can play a role in patients with mosquito bite-induced anaphylaxis. It may also result in severe side effects and one must determine the benefit versus risks for each individual patient.

Entomologic Inoculation Rates of Anopheles arabiensis in Southwestern Ethiopia

PubMed Central

Massebo, Fekadu; Balkew, Meshesha; Gebre-Michael, Teshome; Lindtjørn, Bernt

2013-01-01

We collected anophelines every second week for one year from randomly selected houses in southwestern Ethiopia by using Centers for Disease Control (CDC) light traps, pyrethrum spray catches, and artificial pit shelter constructions to detect circumsporozoite proteins and estimate entomologic inoculation rates (EIRs). Of 3,678 Anopheles arabiensis tested for circumsporozoite proteins, 11 were positive for Plasmodium falciparum and three for P. vivax. The estimated annual P. falciparum EIR of An. arabiensis was 17.1 infectious bites per person per year (95% confidence interval = 7.03–34.6) based on CDC light traps and 0.1 infectious bites per person per year based on pyrethrum spray catches. The P. falciparum EIRs from CDC light traps varied from 0 infectious bites per person per year (in 60% of houses) to 73.2 infectious bites per person per year in the house nearest the breeding sites. Risk of exposure to infectious bites was higher in wet months than dry months, with a peak in April (9.6 infectious bites per person per month), the period of highest mosquito density. PMID:23878184

Entomologic inoculation rates of Anopheles arabiensis in southwestern Ethiopia.

PubMed

Massebo, Fekadu; Balkew, Meshesha; Gebre-Michael, Teshome; Lindtjørn, Bernt

2013-09-01

We collected anophelines every second week for one year from randomly selected houses in southwestern Ethiopia by using Centers for Disease Control (CDC) light traps, pyrethrum spray catches, and artificial pit shelter constructions to detect circumsporozoite proteins and estimate entomologic inoculation rates (EIRs). Of 3,678 Anopheles arabiensis tested for circumsporozoite proteins, 11 were positive for Plasmodium falciparum and three for P. vivax. The estimated annual P. falciparum EIR of An. arabiensis was 17.1 infectious bites per person per year (95% confidence interval = 7.03-34.6) based on CDC light traps and 0.1 infectious bites per person per year based on pyrethrum spray catches. The P. falciparum EIRs from CDC light traps varied from 0 infectious bites per person per year (in 60% of houses) to 73.2 infectious bites per person per year in the house nearest the breeding sites. Risk of exposure to infectious bites was higher in wet months than dry months, with a peak in April (9.6 infectious bites per person per month), the period of highest mosquito density.

Duration-dependent effects of the bite-raised condition on hippocampal function in SAMP8 mice.

PubMed

Arakawa, Yoko; Ichihashi, Yukiko; Iinuma, Mitsuo; Tamura, Yasuo; Iwaku, Fumihiko; Kubo, Kin-Ya

2007-11-01

We evaluated the effect of the duration of occlusal disharmony induced chronic stress on hippocampal function by examining spatial memory in the Morris water maze and on the number of hippocampal neurons in aged senescence-accelerated prone (SAMP8) mice. The bite of SAMP8 mice was raised 0.1 mm using dental adhesive. Groups of mice were tested in the Morris water maze 8, 11, or 22 d after raising the bite. The results indicated that the longer the duration of the bite-raised condition, the greater the impairment in spatial learning ability and the greater the decrease in the number of neurons in the hippocampal CA3 subfield. Thus, behavioral and morphologic deficits induced by the bite-raised condition in aged SAMP8 mice are influenced by the duration of the occlusal disharmony.

Bites by the white-lipped pit viper (Trimeresurus albolabris) and other species in Hong Kong. A survey of 4 years' experience at the Prince of Wales Hospital.

PubMed

Cockram, C S; Chan, J C; Chow, K Y

1990-04-01

The case records of 242 snake bite victims admitted to the Prince of Wales Hospital in Hong Kong between September 1984 and October 1988 were studied retrospectively. When the snake was identified, the White-lipped pit viper (Trimeresurus albolabris) was by far the commonest species involved. In addition to local oedema and inflammation, evidence of a significant blood clotting disturbance was present in at least 10% of cases, defibrination and thrombocytopenia being the commonest findings. Since such abnormality was not always sought the true figure is likely to be higher. Three fatalities occurred, one of which was secondary to a probable White-lipped pit viper bite, one to a bite by Chinese cobra and one to a bite by Russell's viper.

Decline in hospitalisations due to dog bite injuries in Catalonia, 1997-2008. An effect of government regulation?

PubMed

Villalbí, Joan R; Cleries, Montse; Bouis, Susana; Peracho, Víctor; Duran, Julia; Casas, Conrad

2010-12-01

To analyse population-based data on hospitalisation caused by dog bite injuries after changes in legal regulations on dog ownership, including breed-specific regulations. Descriptive study. Hospitals in Catalonia (Spain), 1997-2008. Persons hospitalised with injuries caused by dog bites. There has been a significant decline in hospitalisation caused by injuries from dog bites from 1.80/100,000 in 1997-9 to 1.11/100,000 in 2006-8, after the enactment of stricter regulations on dog ownership in 1999 and 2002. The magnitude of this change is significant (-38%), and has been greatest in less urban settings. Government regulations were associated with a sizable decrease in injuries caused by dog bites in Catalonia. More evaluative studies in this field may provide criteria to focus future regulations and other preventive interventions.

Identification of chromosomal locations associated with tail biting and being a victim of tail-biting behaviour in the domestic pig (Sus scrofa domesticus).

PubMed

Wilson, Kaitlin; Zanella, Ricardo; Ventura, Carlos; Johansen, Hanne Lind; Framstad, Tore; Janczak, Andrew; Zanella, Adroaldo J; Neibergs, Holly Louise

2012-11-01

The objective of this study was to identify loci associated with tail biting or being a victim of tail biting in Norwegian crossbred pigs using a genome-wide association study with PLINK case-control analysis. DNA was extracted from hair or blood samples collected from 98 trios of crossbred pigs located across Norway. Each trio came from the same pen and consisted of one pig observed to initiate tail biting, one pig which was the victim of tail biting and a control pig which was not involved in either behaviour. DNA was genotyped using the Illumina PorcineSNP60 BeadChip whole-genome single-nucleotide polymorphism (SNP) assay. After quality assurance filtering, 53,952 SNPs remained comprising 74 animals (37 pairs) for the tail biter versus control comparison and 53,419 SNPs remained comprising 80 animals (40 pairs) for the victim of tail biting versus control comparison. An association with being a tail biter was observed on Sus scrofa chromosome 16 (SSC16; p = 1.6 × 10(-5)) and an unassigned chromosome (p = 3.9 × 10(-5)). An association with being the victim of tail biting was observed on Sus scrofa chromosomes 1 (SSC1; p = 4.7 × 10(-5)), 9 (SSC9; p = 3.9 × 10(-5)), 18 (SSC18; p = 7 × 10(-5) for 9,602,511 bp, p = 3.4 × 10(-5) for 9,653,881 bp and p = 5.3 × 10(-5) for 29,577,783 bp) and an unassigned chromosome (p = 6.1 × 10(-5)). An r(2) = 0.96 and a D' = 1 between the two SNPs at 9 Mb on SSC18 indicated extremely high linkage disequilibrium, suggesting that these two markers represent a single locus. These results provide evidence of a moderate genetic association between the propensity to participate in tail-biting behaviour and the likelihood of becoming a victim of this behaviour.

Insect Allergy.

PubMed

Lee, Hobart; Halverson, Sara; Mackey, Regina

2016-09-01

Insect bites and stings are common. Risk factors are mostly associated with environmental exposure. Most insect bites and stings result in mild, local, allergic reactions. Large local reactions and systemic reactions like anaphylaxis are possible. Common insects that bite or sting include mosquitoes, ticks, flies, fleas, biting midges, bees, and wasps. The diagnosis is made clinically. Identification of the insect should occur when possible. Management is usually supportive. For anaphylaxis, patients should be given epinephrine and transported to the emergency department for further evaluation. Venom immunotherapy (VIT) has several different protocols. VIT is highly effective in reducing systemic reactions and anaphylaxis. Copyright © 2016 Elsevier Inc. All rights reserved.

Microbiology of animal bite wound infections.

PubMed

Abrahamian, Fredrick M; Goldstein, Ellie J C

2011-04-01

The microbiology of animal bite wound infections in humans is often polymicrobial, with a broad mixture of aerobic and anaerobic microorganisms. Bacteria recovered from infected bite wounds are most often reflective of the oral flora of the biting animal, which can also be influenced by the microbiome of their ingested prey and other foods. Bacteria may also originate from the victim's own skin or the physical environment at the time of injury. Our review has focused on bite wound infections in humans from dogs, cats, and a variety of other animals such as monkeys, bears, pigs, ferrets, horses, sheep, Tasmanian devils, snakes, Komodo dragons, monitor lizards, iguanas, alligators/crocodiles, rats, guinea pigs, hamsters, prairie dogs, swans, and sharks. The medical literature in this area has been made up mostly of small case series or case reports. Very few studies have been systematic and are often limited to dog or cat bite injuries. Limitations of studies include a lack of established or inconsistent criteria for an infected wound and a failure to utilize optimal techniques in pathogen isolation, especially for anaerobic organisms. There is also a lack of an understanding of the pathogenic significance of all cultured organisms. Gathering information and conducting research in a more systematic and methodical fashion through an organized research network, including zoos, veterinary practices, and rural clinics and hospitals, are needed to better define the microbiology of animal bite wound infections in humans.

[Facial dog bite injuries in children: retrospective study of 77 cases].

PubMed

Hersant, B; Cassier, S; Constantinescu, G; Gavelle, P; Vazquez, M-P; Picard, A; Kadlub, N

2012-06-01

The face is the area most vulnerable for dog bites in children. Surgical management is an emergency to prevent infection, functional and aesthetic outcomes. The aim of this study was to define a new gravity scale, and to determine a prevention policy. In our maxillofacial and plastic surgery department, we conducted a retrospective study from 2002 to 2010, including 77 children under 16 years old, victims of facial dog bite. We analyzed epidemiological, clinical data, surgical outcomes. The mean age was 5.36 years. Dogs were principally represented by class I and II dogs; 27,7% of them had ever bitten before. In almost all the cases, the dogs belong to the family or closers. Twenty-one percent of children belong to an unfavourable social environment; 71.43% of dog bites interested the central area of the face. The bites were deep in 77% of cases with amputation or extensive loss of substance in 31% of cases. The healing time was 10.54 months. Nearly a third of patients required several surgeries; 41.56% of patients had aesthetic and functional sequelae; 35.1% of children had psychological problems afterward. Facial children dog bites require a multidisciplinary approach, and a long-term follow-up. We propose a new classification of dog bite severity, more appropriate to the face. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Some relations between classically conditioned aggression and conditioned suppression in squirrel monkeys.

PubMed Central

Hake, D F; Campbell, R L

1980-01-01

During three experiments with squirrel monkeys, stimulus and shock pairings were given in the presence of a bite tube. Experiments 1 and 2 used a conditioned-suppression procedure in which bar pressing was reinforced with food. A transparent shield prevented biting of the bar. When the stimulus was paired with shock, bar pressing decreased (conditioned suppression) and tube biting increased during the stimulus (classically conditioned aggression). When the bite tube was removed on alternate sessions in Experiment 2, there was more suppression when the tube was present, thus suggesting that biting competed with bar pressing. However, this simple competing-response interpretation was complicated by the findings of Experiment 3 where, with naive monkeys, bar pressing was never reinforced with food, yet bar pressing was induced during the stimulus and was highest when the bite tube was absent. The fact that stimulus-induced bar pressing developed inciated that bar pressing in conditioned-suppression procedures, suppressed or not, may be maintained by two types of control--the food reinforcer and induced CS control. The higher rate of induced bar pressing during the stimulus with the bite tube absent confounds a simple competing response interpretation of conditioned suppression. It suggests that shock-induced responses during conditioned suppression could be both contributing to and competing with responding maintained by food, with the net effect depending on specific but ill-defined features of the situation. PMID:7190996

Gingival abscess due to an unusual nail-biting habit: a case report.

PubMed

Sousa, Denise; Pinto, Daniela; Araujo, Rebecca; Rego, Rodrigo Otavio; Moreira-Neto, Jose

2010-03-01

Nail-biting is one of the most frequent deleterious oral habits in children. It can result in systemic diseases or oral traumatic lesion. This report describes a case of gingival abscess in a child due to a fingernail-biting habit. A 5-year, 6-month-old female presented gingival swelling and fistula in the primary maxillary left central and right lateral incisors as an unusual sequelae to the periodontal tissues from fingernail-biting. A periodontal curette was used to remove the fragments and to curette the area. After the curettage, an exudate of blood and pus was drained. Then the area was irrigated with 0.12% chlorhexidine solution; applying finger pressure controlled the secretion. After one week, the patient returned with gingival swelling present in the same teeth. The same curettage procedure was performed. It was suggested that the deleterious habit was related to emotional tension and anxiety behaviors and the patient was referred for psychological treatment. When the patient returned one month later, she was still biting her fingernails, but she had stopped placing fragments into the gingival crevice. No more gingival inflammation or swelling was observed. his paper presents an unusual case report of a gingival abscess due to a fingernail-biting habit in a child, probably related to an emotional condition. The fingernail-biting habit can induce a periodontal traumatic injury yielding a more serious complication such as a gingival abscess.

Microbiology of Animal Bite Wound Infections

PubMed Central

Abrahamian, Fredrick M.; Goldstein, Ellie J. C.

2011-01-01

Summary: The microbiology of animal bite wound infections in humans is often polymicrobial, with a broad mixture of aerobic and anaerobic microorganisms. Bacteria recovered from infected bite wounds are most often reflective of the oral flora of the biting animal, which can also be influenced by the microbiome of their ingested prey and other foods. Bacteria may also originate from the victim's own skin or the physical environment at the time of injury. Our review has focused on bite wound infections in humans from dogs, cats, and a variety of other animals such as monkeys, bears, pigs, ferrets, horses, sheep, Tasmanian devils, snakes, Komodo dragons, monitor lizards, iguanas, alligators/crocodiles, rats, guinea pigs, hamsters, prairie dogs, swans, and sharks. The medical literature in this area has been made up mostly of small case series or case reports. Very few studies have been systematic and are often limited to dog or cat bite injuries. Limitations of studies include a lack of established or inconsistent criteria for an infected wound and a failure to utilize optimal techniques in pathogen isolation, especially for anaerobic organisms. There is also a lack of an understanding of the pathogenic significance of all cultured organisms. Gathering information and conducting research in a more systematic and methodical fashion through an organized research network, including zoos, veterinary practices, and rural clinics and hospitals, are needed to better define the microbiology of animal bite wound infections in humans. PMID:21482724

Predicting the Start of the Aedes albopictus (Diptera: Culicidae) Female Adult Biting Season Using the Spring Temperature in Japan

PubMed Central

Higa, Yukiko; Muto, Atsushi; Hirabayashi, Kimio; Yoshida, Masahiro; Sato, Takashi; Nihei, Naoko; Sawabe, Kyoko; Kobayashi, Mutsuo

2017-01-01

Abstract Aedes albopictus (Skuse) (Diptera: Culicidae) is distributed widely and is common in much of Japan. In Japan, female adults begin to bite in between April and June, except in the southern subtropics where the mosquito has no dormant period. It is difficult to estimate the first Ae. albopictus biting day because it varies annually depending on the location. Over several years, we surveyed the mosquitoes at different locations that covered a range of warmer to cooler areas of Japan. We found an association between the timing of first biting day by Ae. albopictus and spring temperature. In spring months, the strongest correlation was found with mean April temperatures, followed by March. Based on these data, it may, therefore, be possible to apply a simple formula to predict the timing of the first biting day at various geographical locations in Japan. Forecasting maps were created using a simple prediction formula. We found that the first biting day for Ae. albopictus changed depending on early spring temperatures for each year. There was an approximate 20-d difference in first biting day between years with warmer and cooler springs. This prediction model will provide useful insight for planning and practice of Ae. albopictus control programs, targeting larvae and adults, in temperate regions globally. PMID:28968909

Tooth movement using palatal implant supported anchorage compared to conventional dental anchorage.

PubMed

Borsos, Gabriella; Vokó, Zoltan; Gredes, Tomasz; Kunert-Keil, Christiane; Vegh, Andras

2012-11-01

Tooth stability is one of the most changing parameters in age. The aim of the present study has been to clarify the therapeutic benefit of the osseointegrated palatal implant (PI) supported anchorage in adolescents compared with conventional dental anchorage (DA) in extraction cases requiring 'maximum anchorage' in growing patients following the post pubertal growth spurt. Thirty patients (14.22±1.37 years) selected with homogeneous facial skeletal characteristics were divided in two groups. In the PI group, Orthosystem(®) implants were placed into the palate for anchorage and the transpalatal arch (TPA) was fixed to the implant and to the molar bands. In the DA group maximal anchorage was provided by a TPA and a utility arch. Super-elastic spring was used for canine- and contraction arch for incisor retraction. An insignificant difference was observed between the groups as to the duration of the canine retraction. In the PI group, the duration of the front retraction and the total treatment time was shorter compared to the DA group (P<0.05). No significant difference in molar mesial movement was found during canine retraction, but during front retraction, there was significantly less mesial molar movement in the PI group compared to the DA group (P<0.05). The use of palatal implant-based anchorage does not offer a shorter canine retraction period, but resulted in a significant shortening of the front-retraction phase and a total treatment time shortened by 5 months on average. The tooth stability in adolescent patients is adequate for tooth movements using both methods. Copyright © 2012 Elsevier GmbH. All rights reserved.

Effects of Bulk Composition on the Atmospheric Dynamics on Close-in Exoplanets

NASA Astrophysics Data System (ADS)

Zhang, Xi; Showman, Adam P.

2017-02-01

Super Earths and mini Neptunes likely have a wide range of atmospheric compositions, ranging from low molecular mass atmospheres of H2 to higher molecular atmospheres of water, CO2, N2, or other species. Here we systematically investigate the effects of atmospheric bulk compositions on temperature and wind distributions for tidally locked sub-Jupiter-sized planets, using an idealized 3D general circulation model (GCM). The bulk composition effects are characterized in the framework of two independent variables: molecular weight and molar heat capacity. The effect of molecular weight dominates. As the molecular weight increases, the atmosphere tends to have a larger day-night temperature contrast, a smaller eastward phase shift in the thermal phase curve, and a smaller zonal wind speed. The width of the equatorial super-rotating jet also becomes narrower, and the “jet core” region, where the zonal-mean jet speed maximizes, moves to a greater pressure level. The zonal-mean zonal wind is more prone to exhibit a latitudinally alternating pattern in a higher molecular weight atmosphere. We also present analytical theories that quantitatively explain the above trends and shed light on the underlying dynamical mechanisms. Those trends might be used to indirectly determine the atmospheric compositions on tidally locked sub-Jupiter-sized planets. The effects of the molar heat capacity are generally small. But if the vertical temperature profile is close to adiabatic, molar heat capacity will play a significant role in controlling the transition from a divergent flow in the upper atmosphere to a jet-dominated flow in the lower atmosphere.

USDA-ARS Knipling-Bushland U.S. Livestock Insects Research Laboratory Tick & Biting Fly Research Unit scientific update

USDA-ARS?s Scientific Manuscript database

Ticks and biting flies cause tremendous economic damage to the U.S. livestock industry while also being a health concern to humans. Research on their biology and control is done at the Knipling-Bushland U.S. Livestock Insects Research Laboratory, Tick and Biting Fly Research Unit with scientists loc...

Bedbugs: An Equal Opportunist and Cosmopolitan Creature

ERIC Educational Resources Information Center

Krause-Parello, Cheryl A.; Sciscione, Patricia

2009-01-01

Currently there is a rise in bedbugs seen in schools. The wingless, blood-sucking insects can arrive at school via student book bags, student clothing, or other personal items. If a student presents in the health office with a bite mark, the school nurse will need to differentiate between a bedbug bite and other insect bites, such as fleas,…

Identification of the mosquito biting deterrent constituents from the Indian folk remedy plant Jatropha curcas

USDA-ARS?s Scientific Manuscript database

An investigation of the Indian folk remedy plant, Jatropha curcas, was performed to specifically identify the constituents responsible for the mosquito biting deterrent activity of the oil as a whole. Jatropha curcas seed oil is burned in oil lamps in India and part of Africa to repel biting insect...

Reduction of mosquito biting-pressure: spatial repellents or mosquito traps? A field comparison of seven commercially available products in Israel

USDA-ARS?s Scientific Manuscript database

The personal protection capability of seven commercially available mosquito control devices (MCD) is compared under field conditions in Israel. Trials were performed in a high biting-pressure area inhabited by large populations of mosquito and biting midge species and using human volunteers for lan...

Relax and Try This Instead: Abbreviated Habit Reversal for Maladaptive Self-Biting.

ERIC Educational Resources Information Center

Jones, Kevin M.; Swearer, Susan M.; Friman, Patrick C.

1997-01-01

A study evaluated the effectiveness of an abbreviated habit reversal procedure to reduce maladaptive oral self-biting in an adolescent boy in residential care. Treatment involved a combination of relaxation and two competing responses (gum chewing and tongue-lip rubbing). The intervention eliminated the biting and the tissue damage it caused.…

Human cytokine response to Texas crotaline envenomation before and after antivenom administration.

PubMed

Crocker, Patrick; Zad, Omid; Milling, Truman; Maxson, Todd; King, Benjamin; Whorton, Elbert

2010-10-01

The aim of this study was to characterize the human cytokine response to Texas crotaline envenomation before and after antivenom administration. This study enrolled crotaline bite victims presenting to a regional trauma center and children's hospital from March to November 2007 and age-matched unbitten controls. Blood spot cards were obtained from bite victims at presentation and at 1 and 6 hours after antivenom administration. One control sample was drawn from each of the age-matched controls selected from urgent care patients presenting for minor complaints. Samples were delivered to a laboratory using a proprietary method for quantitative evaluation of a large number of biomarkers in parallel with bead-based multiplex immunoassays. After obtaining informed consent, 14 crotaline bite victims (age range, 5-85 years; median age, 45 years; 50% female) (Snakebite Severity Score, 2-7; median, 3) and 14 age-matched controls were enrolled. There were 7 copperhead (Agkistrodon contortrix) bites, 4 rattlesnake (probably Western Diamondback Crotalus atrox) bites, 2 cottonmouth (Agkistrodon piscivorus) bites, and 1 bite from a snake that was not identified by the victim. In t tests, the means in the presentation samples for apolipoprotein A-I (Apo A-I), Apo C3, interleukin 4 (IL-4), myeloperoxidase, plasminogen activator inhibitor 1 (PAI-1), epidermal growth factor, and regulated upon activation, normal t-cell expressed and secreted were significantly lower and Apo H was significantly higher in the bite patients than in the controls. In the 1-hour sample, α(1)-antitrypsin, Apo A-I, Apo C3, eotaxin, IL-4, myeloperoxidase, and PAI-1 levels were lower and prostatic acid phosphatase and cancer antigen 125 levels were higher in the bite patients than in the controls. And in the 6-hour sample, α(1)-antitrypsin, Apo A-I, Apo C3, endothelin-1, IL-4, macrophage inflammatory protein 1β, myeloperoxidase, and epidermal growth factor levels were lower and Apo H level was higher in the bite patients than in controls (all P values < .05). Crotaline venom produces a broad cytokine response in human bite victims. In particular, IL-4, myeloperoxidase, and Apo A-I and C3 levels remain altered despite antivenom therapy, whereas PAI-1 and regulated upon activation, normal t-cell expressed and secreted levels seem to normalize after antivenin as other markers are affected. Understanding this profile and further study of the markers identified might lead to improved therapies and better prognostic indicators. Copyright © 2010 Elsevier Inc. All rights reserved.

Snakebite Survivors Club: retrospective review of rattlesnake bites in Central California.

PubMed

Spano, Susanne; Macias, Fernando; Snowden, Brandy; Vohra, Rais

2013-07-01

We investigated clinical patterns of crotaline envenomation presenting to a tertiary-care academic hospital in Central California over a 10-year period. An IRB-approved, retrospective chart review was conducted on all patients diagnosed with snakebite from December 2000 to December 2010. Data abstracted: demographics, anatomic location of bite, comorbid conditions and intoxicants, length of stay, antivenom dose, laboratory results, and complications or procedures. There were 46 snakebite cases admitted over the study period. Five were "dry bites"; the remaining cases (41/46) received antivenom. There was a male predominance (83% male victims). Upper extremity bites were more common (32/41 upper vs 10/42 lower extremity). One victim sustained bilateral bites to the hands. Thirty-five patients (85%) were admitted, with an average length of stay 2.12 days. The longest hospitalization was 15 days. There were no fatalities. The average time from bite to ED presentation was 2 h 44 min. Bites occurred during every month except November, with the majority occurring during spring and summer months and peaking in June (12/42 cases). Most bites occurred in the hours between noon and 8 pm. The amount of antivenom given ranged from 2 to 35 vials (average, 9 vials). Interfacility transfers were common in our study population: thirteen (32%) patients were transferred into our emergency department for a higher level of care, and 3 (7%) were transferred out (two because of insurance requirements, and one for higher level of Pediatric ICU care). There were no surgical interventions in our study group. Intoxication did not appear to play a major role in this population as only 3 patients (7%) were found to be acutely intoxicated: one with cannabis and amphetamines, 1 with alcohol, and 1 with opioids. In Central California, crotaline envenomations occurred mainly in adult males. Dry bites, or bites not requiring antivenom administration, were uncommon, comprising only 10% of bites in this study population. Contrary to popular and clinical beliefs, substance abuse and/or alcohol intoxication did not appear to play a role in the majority of patients in this study. Care providers and snakebite specialists should be aware that snakebite patients are often transferred between facilities, a finding that may be useful in designing future first aid protocols and research. We hope these findings add concrete data and help correct some common misconceptions about snakebites in Central California. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of bite size and duration of oral processing on retro-nasal aroma release - features contributing to meal termination.

PubMed

Ruijschop, Rianne M A J; Zijlstra, Nicolien; Boelrijk, Alexandra E M; Dijkstra, Annereinou; Burgering, Maurits J M; Graaf, Cees de; Westerterp-Plantenga, Margriet S

2011-01-01

The brain response to a retro-nasally sensed food odour signals the perception of food and it is suggested to be related to satiation. It is hypothesised that consuming food either in multiple small bite sizes or with a longer durations of oral processing may evoke substantial oral processing per gram consumed and an increase in transit time in the oral cavity. This is expected to result in a higher cumulative retro-nasal aroma stimulation, which in turn may lead to increased feelings of satiation and decreased food intake. Using real-time atmospheric pressure chemical ionisation-MS, in vivo retro-nasal aroma release was assessed for twenty-one young, healthy and normal-weight subjects consuming dark chocolate-flavoured custard. Subjects were exposed to both free or fixed bite size (5 and 15 g) and durations of oral processing before swallowing (3 and 9 s) in a cross-over design. For a fixed amount of dark chocolate-flavoured custard, consumption in multiple small bite sizes resulted in a significantly higher cumulative extent of retro-nasal aroma release per gram consumed compared with a smaller amount of large bite sizes. In addition, a longer duration of oral processing tended to result in a higher cumulative extent of retro-nasal aroma release per gram consumed compared with a short duration of oral processing. An interaction effect of bite size and duration of oral processing was not observed. In conclusion, decreasing bite size or increasing duration of oral processing led to a higher cumulative retro-nasal aroma stimulation per gram consumed. Hence, adapting bite size or duration of oral processing indicates that meal termination can be accelerated by increasing the extent of retro-nasal aroma release and, subsequently, the satiation.

Morbidity of pediatric dog bites: a case series at a level one pediatric trauma center.

PubMed

Garvey, Erin M; Twitchell, Denice K; Ragar, Rebecca; Egan, John C; Jamshidi, Ramin

2015-02-01

Pediatric dog bite injuries are common and vary in severity. We sought to characterize predisposing factors, required interventions, and morbidity. A prospective clinical database at a level one pediatric trauma center was reviewed for dog bite injuries over 74 consecutive months ending December 2013. This included all patients brought in by ambulance and/or seen by the trauma team. Of 650 dog bite incidents, 282 met the criteria for inclusion in the trauma database. Median age was 5 years (range, 2 months to 17 years) and 55% (154/282) of patients were male. Pit bulls were most frequently responsible, accounting for 39% (83/213) of incidents in which dog breed was documented. Fifty-three percent (150/282) of dogs belonged to the patient's immediate or extended family. Sixty-nine percent (194/282) of patients required operative intervention: 76% laceration repairs, 14% tissue transfers, and 2% neurosurgical interventions. The most severe injuries were depressed skull fractures, intracranial hemorrhage, laryngotracheal transection, and bilateral orchiectomy. Median length of stay was 1 day (range, 0 to 25 days). There were no mortalities. Pediatric dog bites span a wide range of ages, frequently require operative intervention, and can cause severe morbidity. Dog familiarity did not confer safety, and in this series, Pit bulls were most frequently responsible. These findings have great relevance for child safety. Pediatric dog bites are common and can vary in severity from superficial wounds to life-threatening injuries. Dog familiarity may confer a false sense of safety. A national dog bite prevention and education campaign should be developed with the goal of decreasing the incidence of pediatric dog bites. Copyright © 2015 Elsevier Inc. All rights reserved.

Mosquito biting activity on humans & detection of Plasmodium falciparum infection in Anopheles stephensi in Goa, India.

PubMed

Korgaonkar, Nandini S; Kumar, Ashwani; Yadav, Rajpal S; Kabadi, Dipak; Dash, Aditya P

2012-01-01

Knowledge of the bionomics of mosquitoes, especially of disease vectors, is essential to plan appropriate vector avoidance and control strategies. Information on biting activity of vectors during the night hours in different seasons is important for choosing personal protection measures. This study was carried out to find out the composition of mosquito fauna biting on humans and seasonal biting trends in Goa, India. Biting activities of all mosquitoes including vectors were studied from 1800 to 0600 h during 85 nights using human volunteers in 14 different localities of three distinct ecotypes in Goa. Seasonal biting trends of vector species were analysed and compared. Seasonal biting periodicity during different phases of night was also studied using William's mean. A total of 4,191 mosquitoes of five genera and 23 species were collected. Ten species belonged to Anopheles, eight to Culex, three to Aedes and one each to Mansonia and Armigeres. Eleven vector species had human hosts, including malaria vectors Anopheles stephensi (1.3%), An. fluviatilis (1.8%), and An. culicifacies (0.76%); filariasis vectors Culex quinquefasciatus (40.8%) and Mansonia uniformis (1.8%); Japanese encephalitis vectors Cx. tritaeniorhynchus (17.4%), Cx. vishnui (7.7%), Cx. pseudovishnui (0.1%), and Cx. gelidus (2.4%); and dengue and chikungunya vectors Aedes albopictus (0.9%) and Ae. aegypti (0.6%). Two An. stephensi of the total 831 female anophelines, were found positive for P. falciparum sporozoites. The entomological inoculation rate (EIR) of P. falciparum was 18.1 and 2.35 for Panaji city and Goa, respectively. Most of the mosquito vector species were collected in all seasons and throughout the scotophase. Biting rates of different vector species differed during different phases of night and seasons. Personal protection methods could be used to stop vector-host contact.

Rat-bites of an epidemic proportion in Peshawar vale; a GIS based approach in risk assessment.

PubMed

Fatima, Syeda Hira; Zaidi, Farrah; Adnan, Muhammad; Ali, Asad; Jamal, Qaiser; Khisroon, Muhammad

2018-03-19

Contemporary studies demonstrate that rodent bites do not occur frequently. However, a huge number of cases were reported from Peshawar vale, Pakistan during 2016. Two species, the local black rat Rattus rattus (Linnaeus, 1758) and the invasive brown rat Rattus norvegicus (Berkenhout, 1769) might be the suspected cause. Several studies indicated the invasion of brown rats into Pakistan presumably via port city of Karachi. In this study, we modeled geospatial distribution of rodent bites for risk assessment in the region. Bite cases reported to tertiary care lady reading hospital were monitored from January 1 to August 31, 2016. Among 1747 cases, statistically informative data (n = 1295) was used for analyses. MaxEnt algorithm was employed for geospatial modeling, taking into account various environmental variables (temperature, precipitation, humidity, and elevation) and anthropogenic factors (human population density, distance from roads, distance from water channels, and land use/land cover). MaxEnt results revealed that urban slums (84.5%) are at highest risk followed by croplands (10.9%) and shrublands (2.7%). Anthropogenic factors affecting incidence of rodent bites included host density (contribution: 34.7), distance from water channels (3.2), land use/land cover (2.8), and distance from roads (2). Most of the cases occurred within a radius of 0.3 km from roads and 5 km from water channels. Rodent bite incidence is currently at its peak in Peshawar vale. Factors significantly affecting rodents' bite activity and their distribution and dispersal include urbanization, distance from roads, and water channels. Further studies are needed to determine the impact of invasion by brown rat on bite incidence.

Escape rates and biting histories of dogs confined to their owner's property through the use of various containment methods.

PubMed

Starinsky, Nicole S; Lord, Linda K; Herron, Meghan E

2017-02-01

OBJECTIVE To determine escape rates for dogs confined to their owner's property by various containment methods and determine whether biting history was associated with containment method. DESIGN Cross-sectional survey. SAMPLE 974 owners of 1,053 dogs. PROCEDURES Individuals patronizing pet stores in Columbus, Ohio, were recruited to complete a survey on the method they used to confine their dogs to their property and their dogs' behavior history. RESULTS Dogs were confined to their owner's property by a physical fence (821/1,053 [78.0%]), electronic fence (150/1,053 [14.2%]), or tether system (82/1,053 [7.8%]). Dogs confined by an electronic fence were more likely to have escaped (66/150 [44.0%]) than were dogs confined by a see-through fence (153/658 [23.3%]), privacy fence (38/163 [23.3%]), or tether (22/82 [26.8%]). Forty-eight (4.6%) dogs had reportedly bitten a person in the past, and 81 (7.7%) had reportedly bitten another dog, but containment method was not significantly associated with whether dogs had ever bitten a person or another dog. Greeting behavior (growling, snarling, or trying to bite) was significantly associated with a history of biting a person or another dog. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that escape rate, but not biting history, was associated with the method owners used to confine dogs to their properties. Greeting behavior was associated with biting history, suggesting that owners of dogs that growl, snarl, or attempt to bite when meeting an unfamiliar person or dog should seek assistance to prevent future bites.

Exploring lay perceptions of the causes of crib-biting/windsucking behaviour in horses.

PubMed

Litva, A; Robinson, C S; Archer, D C

2010-05-01

Crib-biting/windsucking behaviour has important consequences for equine health and welfare. Lay perceptions of health and illness are of interest to medical sociologists, providing important information to medical practitioners, but have infrequently been applied in veterinary research. To demonstrate how lay epidemiology can be applied within veterinary research by exploring the lay perceptions regarding the causes of crib-biting/windsucking behaviour in horses. Informants were recruited from professional and amateur horse owners who had or had not owned/cared for a horse that exhibited crib-biting/windsucking behaviour. In-depth interviews were used to examine perceptions about the development of this behaviour within each group until a 'saturation' of themes emerged. The main themes that emerged as causes of crib-biting/windsucking behaviour were 'boredom', 'stress' and 'habit/addiction'. In the group of owners/carers who did not have direct experience of this type of behaviour, 'copying' from other horses emerged as a strong theme and they stated that they would not wish to own a crib-biting/windsucking horse. In contrast, those who had direct experience of horses demonstrating this behaviour did not believe copying was a cause based on their own observations and would not be put off purchasing or caring for another horse displaying this behaviour. Perceptions about what causes crib-biting/windsucking was influenced by whether or not informants had personal experience of horses demonstrating this behaviour. The three main themes that emerged have some justification based on current research and highlight the need for further investigation into the underlying pathophysiology of crib-biting/windsucking behaviour. Qualitative approaches to health, disease and behaviour have an important role in the medical field and are applicable to veterinary research.

Effect of Postnatal Myostatin Inhibition on Bite Mechanics in Mice.

PubMed

Williams, Susan H; Lozier, Nicholas R; Montuelle, Stéphane J; de Lacalle, Sonsoles

2015-01-01

As a negative regulator of muscle size, myostatin (Mstn) impacts the force-production capabilities of skeletal muscles. In the masticatory system, measures of temporalis-stimulated bite forces in constitutive myostatin KOs suggest an absolute, but not relative, increase in jaw-muscle force. Here, we assess the phenotypic and physiologic impact of postnatal myostatin inhibition on bite mechanics using an inducible conditional KO mouse in which myostatin is inhibited with doxycycline (DOX). Given the increased control over the timing of gene inactivation in this model, it may be more clinically-relevant for developing interventions for age-associated changes in the musculoskeletal system. DOX was administered for 12 weeks starting at age 4 months, during which time food intake was monitored. Sex, age and strain-matched controls were given the same food without DOX. Bite forces were recorded just prior to euthanasia after which muscle and skeletal data were collected. Food intake did not differ between control or DOX animals within each sex. DOX males were significantly larger and had significantly larger masseters than controls, but DOX and control females did not differ. Although there was a tendency towards higher absolute bite forces in DOX animals, this was not significant, and bite forces normalized to masseter mass did not differ. Mechanical advantage for incisor biting increased in the DOX group due to longer masseter moment arms, likely due to a more anteriorly-placed masseter insertion. Despite only a moderate increase in bite force in DOX males and none in DOX females, the increase in masseter mass in males indicates a potentially positive impact on jaw muscles. Our data suggest a sexual dimorphism in the role of mstn, and as such investigations into the sex-specific outcomes is warranted.

Extreme Postnatal Scaling in Bat Feeding Performance: A View of Ecomorphology from Ontogenetic and Macroevolutionary Perspectives.

PubMed

Santana, Sharlene E; Miller, Kimberly E

2016-09-01

Ecomorphology studies focus on understanding how anatomical and behavioral diversity result in differences in performance, ecology, and fitness. In mammals, the determinate growth of the skeleton entails that bite performance should change throughout ontogeny until the feeding apparatus attains its adult size and morphology. Then, interspecific differences in adult phenotypes are expected to drive food resource partitioning and patterns of lineage diversification. However, Formal tests of these predictions are lacking for the majority of mammal groups, and thus our understanding of mammalian ecomorphology remains incomplete. By focusing on a fundamental measure of feeding performance, bite force, and capitalizing on the extraordinary morphological and dietary diversity of bats, we discuss how the intersection of ontogenetic and macroevolutionary changes in feeding performance may impact ecological diversity in these mammals. We integrate data on cranial morphology and bite force gathered through longitudinal studies of captive animals and comparative studies of free-ranging individuals. We demonstrate that ontogenetic trajectories and evolutionary changes in bite force are highly dependent on changes in body and head size, and that bats exhibit dramatic, allometric increases in bite force during ontogeny. Interspecific variation in bite force is highly dependent on differences in cranial morphology and function, highlighting selection for ecological specialization. While more research is needed to determine how ontogenetic changes in size and bite force specifically impact food resource use and fitness in bats, interspecific diversity in cranial morphology and bite performance seem to closely match functional differences in diet. Altogether, these results suggest direct ecomorphological relationships at ontogenetic and macroevolutionary scales in bats. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Field evaluation of commercial repellents against the floodwater mosquito Psorophora columbiae (Diptera: Culicidae) in St. Johns County, Florida.

PubMed

Qualls, Whitney A; Xue, Rui-De; Holt, J Adam; Smith, Mike L; Moeller, Jeanne J

2011-11-01

Three plant-based repellents-REPEL LEMON Eucalyptus Insect Repellent Lotion (active ingredient [AI] 30% oil of eucalyptus), Bite Blocker Xtreme Sportsman Organic Insect Repellent ([AI] 3% soybean oil, 6% geranium oil, and 8% castor oil), and Bite Blocker BioUD Insect Repellent ([AI] 7.75% 2-undecanone)--were evaluated against OFF! ([AI] 15% N,N-diethyl-m-toluamide or N,N-diethyl-3-methyl-benzamide, also called DEET) at a field site in Elkton, FL, to determine the mean protection time provided against Psorophora columbiae (Dyar & Knab). These products provided different protection times against biting Ps. columbiae. REPEL provided the longest protection time (330 min) followed by Bite Blocker Xtreme Sportsman (163 min), Bite Blocker BioUD (140 min), and OFF! (130 min). This study provides the first information about plant-based insect repellent protection times against Ps. columbiae.

Rat-bite fever presenting with rash and septic arthritis.

PubMed

Kanechorn Na Ayuthaya, Rajyani; Niumpradit, Nucha

2005-11-01

Rat-bite fever is an uncommon disease known for its endemicity to occur worldwide. Although most patients tend to develop mild symptoms with improvement from conventional antibiotics, it can progress with severe complications with a mortality rate as high as 13% without proper treatment. The authors report a complicated case of rat bite-fever involving a 61-year old woman who presented with fever petechial rash, and septic arthritis following a rat bite. Initially, multiple antibiotics were administered but were not effective. As a consequence, invasive procedures such as arthrotomy and joint debridement were done and prolonged antibiotic was administered until clinical resolution. Since many cases do not have a history of rat bite and may present with fever, rashes, and arthritis it is essential to distinguish it from other diseases. Here, the authors will provide details on the etiology, clinical manifestations, diagnosis, and management to aid prompt detection and treatment of the disease.

A rare cause of severe periorbital edema and dermonecrotic ulcer of the eyelid in a child: brown recluse spider bite.

PubMed

Taşkesen, Mustafa; Akdeniz, Sedat; Taş, Taşkin; Keklikçi, Uğur; Taş, Mehmet Ali

2011-01-01

Spider bites are a worldwide problem. Brown recluse spider bites can lead to severe local or systemic clinical effects, such as edema, necrotic ulcer, rashes, fever, chills, nausea, vomiting, malaise, arthralgia, myalgia, hemolysis, leukocytosis, disseminated intravascular coagulation, renal failure, and death. Eyelid bites from brown recluse spiders are rare. We report a child with severe facial edema and a dermonecrotic ulcer on the eyelid. Upon laboratory examination, leukocytosis with a significant left shift was detected. The patient was treated with antibiotics, systemic corticosteroid and conservative therapy that included saline compresses and ocular lubrication. No surgical excision was required. Vision was not impaired. A dermonecrotic ulcer is a severe complication of brown recluse spider bites. Since the diagnosis is difficult, clinical and epidemiological findings and a detailed history are important for an accurate diagnosis.

Public Health Considerations Associated with the Location and Operation of Off-Leash Dog Parks.

PubMed

Rahim, Tissa; Barrios, Pablo Romero; McKee, Geoffrey; McLaws, Melissa; Kosatsky, Tom

2018-04-01

Off-leash dog parks may enhance human health, but may also lead to health risk through infection or canine aggression. Published evidence was reviewed to examine positive and negative public health impacts of off-leash dog parks, as well as strategies for enhancing benefits and mitigating risks. Evidence suggests that off-leash dog parks can benefit physical and social health, as well as community connectedness. While studies have documented shedding of zoonotic agents in dog parks, the risk of transmission to humans is relatively unknown. Evidence on the risk of dog bites in off-leash dog parks is also limited. Case-examples from North American off-leash dog parks highlight the importance of park location/design, public adherence to safe and hygienic practices, and effective regulatory strategies for mitigating potential risks and maximizing the benefits of off-leash dog parks.

A Novel Role of Periostin in Postnatal Tooth Formation and Mineralization*

PubMed Central

Ma, Dedong; Zhang, Rong; Sun, Yao; Rios, Hector F.; Haruyama, Naoto; Han, Xianglong; Kulkarni, Ashok B.; Qin, Chunlin; Feng, Jian Q.

2011-01-01

Periostin plays multiple functions during development. Our previous work showed a critical role of this disulfide-linked cell adhesion protein in maintenance of periodontium integrity in response to occlusal load. In this study, we attempted to address whether this mechanical response molecule played a direct role in postnatal tooth development. Our key findings are 1) periostin is expressed in preodontoblasts, and odontoblasts; and the periostin-null incisor displayed a massive increase in dentin formation after mastication; 2) periostin is also expressed in the ameloblast cells, and an enamel defect is identified in both the adult-null incisor and molar; 3) deletion of periostin leads to changes in expression profiles of many non-collagenous protein such as DSPP, DMP1, BSP, and OPN in incisor dentin; 4) the removal of a biting force leads to reduction of mineralization, which is partially prevented in periostin-null mice; and 6) both in vitro and in vivo data revealed a direct regulation of periostin by TGF-β1 in dentin formation. In conclusion, periostin plays a novel direct role in controlling postnatal tooth formation, which is required for the integrity of both enamel and dentin. PMID:21131362

Herbst appliance in lingual orthodontics.

PubMed

Wiechmann, Dirk; Schwestka-Polly, Rainer; Hohoff, Ariane

2008-09-01

The aims of this article were to outline a technique for attaching Herbst telescopes to a customized lingual orthodontic (LO) appliance and to demonstrate the treatment phases and outcome with a case report. The interface between the LO appliance and the telescopes consists of a computer-aided design/computer-aided manufacturing (CAD/CAM), custom-made labial pivot base connected to the custom-made bands of the maxillary molars and mandibular canines. The individual CAD depiction of the interface ensures an optimal 3-dimensional tube-and-plunger position for correct and smooth function of the telescope mechanism. Because of the lingual location of the brackets, a small buccal tooth-to-telescope distance can be achieved, increasing patient comfort. Various options of anchorage are possible with only 1 device. After bite jumping, the telescopes and pivot bases can be removed easily without debonding the bands or removing the archwires. Experience from the first patient suggests that the Herbst-LO appliance facilitates treatment control during all phases, decreases the risk of interface breakage and mandibular incisor flaring, and might reduce overall treatment time. These initial clinical observations justify further research to provide evidence about the efficacy of Herbst-LO appliances.

PLAY HANDS PROTECTIVE GLOVES: TECHNICAL NOTE ON DESIGN AND CONCEPT.

PubMed

Houston-Hicks, Michele; Lura, Derek J; Highsmith, M Jason

2016-09-01

Cerebral Palsy (CP) is the leading cause of childhood motor disability, with a global incidence of 1.6 to 2.5/1,000 live births. Approximately 23% of children with CP are dependent upon assistive technologies. Some children with developmental disabilities have self-injurious behaviors such as finger biting but also have therapeutic needs. The purpose of this technical note is to describe design considerations for a protective glove and finger covering that maintains finger dexterity for children who exhibit finger and hand chewing (dermatophagia) and require therapeutic range of motion and may benefit from sensory stimulation resulting from constant contact between glove and skin. Protecting Little and Adolescent Youth (PLAY) Hands are protective gloves for children with developmental disorders such as CP who injure themselves by biting their hands due to pain or sensory issues. PLAY Hands will be cosmetically appealing gloves that provide therapeutic warmth, tactile sensory feedback, range of motion for donning/ doffing, and protection to maximize function and quality of life for families of children with developmental disorders. The technology is either a per-finger protective orthosis or an entire glove solution designed from durable 3D-printed biodegradable/bioabsorbable materials such as thermoplastics. PLAY Hands represent a series of protective hand wear interventions in the areas of self-mutilating behavior, kinematics, and sensation. They will be made available in a range of protective iterations from single- or multi-digit finger orthoses to a basic glove design to a more structurally robust and protective iteration. To improve the quality of life for patients and caregivers, they are conceptualized to be cosmetically appealing, protective, and therapeutic.

Man-biting activity of Anopheles (Nyssorhynchus) albimanus and An. (Kerteszia) neivai (Diptera: Culicidae) in the Pacific lowlands of Colombia.

PubMed

Solarte, Y; Hurtado, C; Gonzalez, R; Alexander, B

1996-01-01

The daily man-biting activity of Anopheles (Nyssorhynchus) albimanus and An. (Kerteszia) neivai was determined in four ecologically distinct settlements of the Naya River, Department of Valle, Colombia. Differences were found among the settlements with respect to the mosquito species present, intradomiciliary and extradomiciliary biting activity and population densities.

A Randomized Controlled Trial of a Novel Self-Help Technique for Impulse Control Disorders: A Study on Nail-Biting

ERIC Educational Resources Information Center

Moritz, Steffen; Treszl, Andras; Rufer, Michael

2011-01-01

Nail-biting is currently classified as an impulse control disorder not otherwise specified. Although seldom targeted as a primary symptom, nail-biting is often associated with somatic complications and decreased quality of life. The present study assessed the effectiveness of an innovative self-help technique, titled decoupling (DC). DC aims at…

Rat Bite Fever and Streptobacillus moniliformis

PubMed Central

Elliott, Sean P.

2007-01-01

Rat bite fever, caused by Streptobacillus moniliformis, is a systemic illness classically characterized by fever, rigors, and polyarthralgias. If left untreated, it carries a mortality rate of 10%. Unfortunately, its nonspecific initial presentation combined with difficulties in culturing its causative organism produces a significant risk of delay or failure in diagnosis. The increasing popularity of rats and other rodents as pets, together with the risk of invasive or fatal disease, demands increased attention to rat bite fever as a potential diagnosis. The clinical and biological features of rat bite fever and Streptobacillus moniliformis are reviewed, providing some distinguishing features to assist the clinician and microbiologist in diagnosis. PMID:17223620

[Management of dog bite trauma of the external genital organs].

PubMed

Dubosq, Francis; Traxer, Olivier; Boublil, Véronique; Gattegno, Bernard; Thibault, Philippe

2004-04-01

Animal bites to the scrotum are rare, but potentially serious. In the light of a personal case, the authors discuss the management of these lesions. An animal bite comprises a triple infectious risk: bacterial, tetanus and rabies. Surgical exploration is indicated for assessment of the structures involved and debridement. The morbidity is related to the severity of the bite and the waiting time before consultation, and complications are rare. Orchidectomy is sometimes necessary, as in the case reported here, and the patient must be warned about this possibility. Antibiotic therapy is empirical: tetracycline and anti-anaerobe antibiotic. Rabies and tetanus prophylaxis must be performed according to vaccine guidelines.

Relative contributions of occlusion, maximum bite force, and chewing cycle kinematics to masticatory performance.

PubMed

Lepley, Casey R; Throckmorton, Gaylord S; Ceen, Richard F; Buschang, Peter H

2011-05-01

The purpose of this study was to explore the contributions of occlusion, maximum bite force, and chewing cycle kinematics to masticatory performance. A prospective cross-sectional study was performed on 30 subjects with Class I occlusion. Masticatory performance was measured with the test food Cuttersil (Heraeus Kulzer, South Bend, Ind) and the fractional-sieve technique. Blu-Mousse (Parkell Biomaterials, Farmingdale, NY) bite registrations were used to measure occlusal contact areas. The American Board of Orthodontics occlusal discrepancies were measured on the subjects' dental models. Maximum bite forces were recorded with a custom transducer, and 3-dimensional chewing cycle kinematics were tracked with an opto-electric computer system and Optotrak software (Northern Digital, Waterloo, Ontario, Canada). Masticatory performance was most closely correlated with occlusal contact area, indicating larger contact areas in subjects with better performance. Occlusal contact area and occlusal discrepancies were also related to bite force and chewing cycle kinematics. Maximum bite force was positively related with masticatory performance. Although masticatory performance is related, both directly and indirectly, to a number of morphologic and functional factors, it is most closely related to occlusal factors. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

A study comparing ultrasound images of tongue movements between open bite children and normal children in the early mixed dentition period.

PubMed

Kikyo, T; Saito, M; Ishikawa, M

1999-09-01

The tongue surface movement of young patients with or without open bite was evaluated by ultrasound images taken on the posterior part of the tongue on the frontal plane to determine whether there is any relationship between the tongue movement and open bite malocclusion in the early mixed dentition period. The standardized reproducible ultrasound images were obtained using ultrasound diagnostic equipment that was fabricated in a cephalostat unit having a probe stabilizer. At the central portion of the tongue, no significant differences were detected in the duration or the momentum of tongue surface movement on a frontal plane was detected between the patients with and without open bite during swallowing. The farther the region was from the central portion, however, the longer the duration and the bigger the momentum of the tongue surface movement was found in the open bite group. Based on this evidence, it is suggested that an open-bite child swallows by using a tongue thrust motion that forms using a large depressed area in the tongue, whereas a normal child without tongue thrust forms a rather narrow groove in the central portion of the tongue when swallowing.

Spectral characteristics of speech with fixed jaw displacements

NASA Astrophysics Data System (ADS)

Solomon, Nancy P.; Makashay, Matthew J.; Munson, Benjamin

2004-05-01

During speech, movements of the mandible and the tongue are interdependent. For some research purposes, the mandible may be constrained to ensure independent tongue motion. To examine specific spectral characteristics of speech with different jaw positions, ten normal adults produced sentences with multiple instances of /t/, /s/, /squflg/, /i/, /ai/, and /squflgi/. Talkers produced stimuli with the jaw free to vary, and while gently biting on 2- and 5-mm bite blocks unilaterally. Spectral moments of /s/ and /squflg/ frication and /t/ bursts differed such that mean spectral energy decreased, and diffuseness and skewness increased with bite blocks. The specific size of the bite block had minimal effect on these results, which were most consistent for /s/. Formant analysis for the vocoids revealed lower F2 frequency in /i/ and at the end of the transition in /ai/ when bite blocks were used; F2 slope for diphthongs was not sensitive to differences in jaw position. Two potential explanations for these results involve the physical presence of the bite blocks in the lateral oral cavity, and the oromotor system's ability to compensate for fixed jaw displacements. [Work supported by NIDCD R03-DC06096.

Insect repellent activity of medicinal plant oils against Aedes aegypti (Linn.), Anopheles minimus (Theobald) and Culex quinquefasciatus Say based on protection time and biting rate.

PubMed

Phasomkusolsil, Siriporn; Soonwera, Mayura

2010-07-01

This study investigated insect bite protection and length of the protection with 30 repellents which were divided into 3 categories: plant oil, essential oil and essential oil with ethyl alcohol, tested against three mosquito species, Aedes aegypti, Anopheles minimus and Culex quinquefasciatus, under laboratory conditions. The plant oil group was comprised of Phlai (Zingiber cassumunar) and Sweet basil (Ocimum basilicum). Both substances were effective as repellents and feeding deterrents against An. minimus (205 minutes protection time and a biting rate of 0.9%), Cx. quinquefasciatus (165 minutes protection time and 0.9% biting rate) and Ae. aegypti (90 minutes protection time and 0.8% biting rate). Essential oil from citronella grass (Cymbopogon nardus) exhibited protection against biting from all 3 mosquito species: for An. minimus, Cx. quinquefasciatus and Ae. aegypti, the results were 130 minutes and 0.9%, 140 minutes and 0.8%, and 115 minutes and 0.8%, respectively. The period of protection time against Ae. aegypti for all repellent candidates tested was lower than the Thai Industrial Standards Institute (TISI) determined time of greater than 2 hours.

The incidence of public sector hospitalisations due to dog bites in Australia 2001-2013.

PubMed

Rajshekar, Mithun; Blizzard, Leigh; Julian, Roberta; Williams, Anne-Marie; Tennant, Marc; Forrest, Alex; Walsh, Laurence J; Wilson, Gary

2017-08-01

To estimate the incidence of dog bite-related injuries requiring public sector hospitalisation in Australia during the period 2001-13. Summary data on public sector hospitalisations due to dog bite-related injuries with an ICD 10-AM W54.0 coding were sourced from the Australian Institute of Health and Welfare for the study period 2001-2013. In Australia, on average, 2,061 persons were hospitalised each year for treatment for dog bite injuries at an annual rate of 12.39 (95%CI 12.25-12.53) per 100,000 during 2001-13. The highest annual rates of 25.95 (95%CI 25.16-26.72) and 18.42 (95%CI 17.75-19.07) per 100,000 were for age groups 0-4 and 5-9 years respectively. Rates of recorded events increased over the study period and reached 16.15 (95%CI 15.78-16.52) per 100,000 during 2011-13. Dog bites are a largely unrecognised and growing public health problem in Australia. Implications for public health: There is an increasing public sector burden of hospitalisations for injuries from dog bites in Australia. © 2017 Menzies Institute for Medical Research.

Epidemiological aspects of snake bites on a Liberian rubber plantation.

PubMed

Stahel, E

1980-12-01

During a one-year period 95 patients with a history of snake bite were admitted to the hospital of a Liberian rubber plantation. The population at risk included the field workers (tappers and slashers) with an incidence of 4.2 symptomatic snake bites per thousand per year. The incidence of symptomatic bites was 1.7 per thousand in the group of non-field employees and 0.4 per thousand per year in the group of non-employees. The temporary disability was between 3 and 5 days, and the loss of workings days due to snake bites was one day per 10,000 working days on the plantation. Among the 95 patients 27 did not show any symptoms of envenoming except occasional fang marks. 64 patients developed cytotoxic symptoms alone. In this group, the night adder (Causus maculatus) was the main responsible snake. 4 patients showed signs of systemic envenoming. Two were haematological and two were neurological in nature and caused by Bitis species and Naja species, respectively. No fatalities were noted. A definite maximum of snake bites was observed during October and November which corresponds to the transition from rainy to dry season.

Age- and bite-structured models for vector-borne diseases.

PubMed

Rock, K S; Wood, D A; Keeling, M J

2015-09-01

The biology and behaviour of biting insects is a vitally important aspect in the spread of vector-borne diseases. This paper aims to determine, through the use of mathematical models, what effect incorporating vector senescence and realistic feeding patterns has on disease. A novel model is developed to enable the effects of age- and bite-structure to be examined in detail. This original PDE framework extends previous age-structured models into a further dimension to give a new insight into the role of vector biting and its interaction with vector mortality and spread of disease. Through the PDE model, the roles of the vector death and bite rates are examined in a way which is impossible under the traditional ODE formulation. It is demonstrated that incorporating more realistic functions for vector biting and mortality in a model may give rise to different dynamics than those seen under a more simple ODE formulation. The numerical results indicate that the efficacy of control methods that increase vector mortality may not be as great as predicted under a standard host-vector model, whereas other controls including treatment of humans may be more effective than previously thought. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Animal and human bite injuries: a 5-year retrospective study in a large urban public hospital in Venezuela.

PubMed

Gelvez, Muñoz; Enrique, Ruben; Gajos, Golaszewski; Bladimir, Jose; Carvajal, Diaz; Luis, Alvaro

2017-12-01

Animal bite injuries to the head and neck regions are an important public health problem. Most of these bites are from dogs. A 10-year retrospective study was undertaken to determine the prevalence of animal and human bites. This retrospective study was done from January 2011 to December 2016 and included 387 patients with a mean age of 21.51 years. Data collection included age, sex, days of hospitalization, lesion type, and clinical management. Majority of patients were in age group of 21-29 years, followed by 31-55 years. Out of the total 281 patients, 42 patients (51.60%) were males and 34 patients (48.40%) were females. Mean hospital stay was 7.2 days with a minimum of 5 days and a maximum of 12 days. Surgical management included cleansing and primary closure of the wound. We concluded that the use of empiric antibiotic prophylaxis is essential for management of facial animal bite, and the antibiotic of first choice is amoxicillin-clavulanic acid. The aim of immediate surgical repair (< 6 h) is to avoid infections. The persistence of dog bite is public health problem in Venezuela.

Effects of simulated moose Alces alces browsing on the morphology of rowan Sorbus aucuparia

USGS Publications Warehouse

Jager, N.R.D.; Pastor, J.

2010-01-01

In much of northern Sweden moose Alces alces browse rowan Sorbus aucuparia heavily and commonly revisit previously browsed plants. Repeated browsing of rowan by moose has created some concern for its long-term survival in heavily browsed areas. We therefore measured how four years of simulated moose browsing at four population densities (0, 10, 30 and 50 moose/1,000 ha) changed plant height, crown width, available bite mass, the number of bites per plant and per plant forage biomass of rowan saplings. Increased biomass removal led to a significant decline in plant height (P < 0.001), but a significant increase in the number of bites per plant (P = 0.012). Increases in the number of bites per plant more than compensated for weak decreases in bite mass, leading to a weak increase in per plant forage biomass (P = 0.072). With the decline in plant height and increase in the number of stems per plant, a greater number of bites remain within the height reach of moose relative to unbrowsed controls. Moose therefore stand to benefit from revisiting previously browsed plants, which may result in feeding loops between moose and previously browsed rowan saplings. ?? 2010 Wildlife Biology, NKV.

Protective value of prophylactic antibiotic treatment of tick bite for Lyme disease prevention: an animal model.

PubMed

Piesman, Joseph; Hojgaard, Andrias

2012-06-01

Clinical studies have demonstrated that prophylactic antibiotic treatment of tick bites by Ixodes scapularis in Lyme disease hyperendemic regions in the northeastern United States can be effective in preventing infection with Borrelia burgdorferi sensu stricto, the Lyme disease spirochete. A large clinical trial in Westchester County, NY (USA), demonstrated that treatment of tick bite with 200mg of oral doxycycline was 87% effective in preventing Lyme disease in tick-bite victims (Nadelman, R.B., Nowakowski, J., Fish, D., Falco, R.C., Freeman, K., McKenna, D., Welch, P., Marcus, R., Agúero-Rosenfeld, M.E., Dennis, D.T., Wormser, G.P., 2001. Prophylaxis with single-dose doxycycline for the prevention of Lyme disease after an Ixodes scapularis tick bite. N. Engl. J. Med. 345, 79-84.). Although this excellent clinical trial provided much needed information, the authors enrolled subjects if the tick bite occurred within 3 days of their clinical visit, but did not analyze the data based on the exact time between tick removal and delivery of prophylaxis. An animal model allows for controlled experiments designed to determine the point in time after tick bite when delivery of oral antibiotics would be too late to prevent infection with B. burgdorferi. Accordingly, we developed a tick-bite prophylaxis model in mice that gave a level of prophylactic protection similar to what had been observed in clinical trials and then varied the time post tick bite of antibiotic delivery. We found that two treatments of doxycycline delivered by oral gavage to mice on the day of removal of a single potentially infectious nymphal I. scapularis protected 74% of test mice compared to controls. When treatment was delayed until 24 h after tick removal, only 47% of mice were protected; prophylactic treatment was totally ineffective when delivered ≥2 days after tick removal. Although the dynamics of antibiotic treatment in mice may differ from humans, and translation of animal studies to patient management must be approached with caution, we believe our results emphasize the point that antibiotic prophylactic treatment of tick bite to prevent Lyme disease is more likely to be efficacious if delivered promptly after potentially infectious ticks are removed from patients. There is only a very narrow window for prophylactic treatment to be effective post tick removal. Published by Elsevier GmbH.

The “Smart Dining Table”: Automatic Behavioral Tracking of a Meal with a Multi-Touch-Computer

PubMed Central

Manton, Sean; Magerowski, Greta; Patriarca, Laura; Alonso-Alonso, Miguel

2016-01-01

Studying how humans eat in the context of a meal is important to understanding basic mechanisms of food intake regulation and can help develop new interventions for the promotion of healthy eating and prevention of obesity and eating disorders. While there are a number of methodologies available for behavioral evaluation of a meal, there is a need for new tools that can simplify data collection through automatic and online analysis. Also, there are currently no methods that leverage technology to add a dimension of interactivity to the meal table. In this study, we examined the feasibility of a new technology for automatic detection and classification of bites during a laboratory meal. We used a SUR40 multi-touch tabletop computer, powered by an infrared camera behind the screen. Tags were attached to three plates, allowing their positions to be tracked, and the saturation (a measure of the infrared intensity) in the surrounding region was measured. A Kinect camera was used to record the meals for manual verification and provide gesture detection for when the bites were taken. Bite detections triggered classification of the source plate by the SUR40 based on saturation flux in the preceding time window. Five healthy subjects (aged 20–40 years, one female) were tested, providing a total sample of 320 bites. Sensitivity, defined as the number of correctly detected bites out of the number of actual bites, was 67.5%. Classification accuracy, defined as the number of correctly classified bites out of those detected, was 82.4%. Due to the poor sensitivity, a second experiment was designed using a single plate and a Myo armband containing a nine-axis accelerometer as an alternative method for bite detection. The same subjects were tested (sample: 195 bites). Using a simple threshold on the pitch reading of the magnetometer, the Myo data achieved 86.1% sensitivity vs. 60.5% with the Kinect. Further, the precision of positive predictive value was 72.1% for the Myo vs. 42.8% for the Kinect. We conclude that the SUR40 + Myo combination is feasible for automatic detection and classification of bites with adequate accuracy for a range of applications. PMID:26903934

Bite wounds and antibiotic prescription among patients presenting to an Australian emergency department.

PubMed

Birdsey, Matthew; Edwards, Gail; Abetz, Jeremy; Jennings, Natasha; Mitra, Biswadev

2016-07-01

Emergency department presentations after mammalian bites may be associated with injection of bacteria into broken skin and may require prophylactic antibiotics to prevent subsequent infection. We aim to describe the epidemiology of patients presenting with a mammalian bite injury and antibiotic choice to an Australian adult tertiary centre. A retrospective cohort study was performed capturing all presentations after mammalian bite wounds between 01 Jan 2014 and 31 Dec 2014. An explicit chart review was conducted to determine management of each case. Cases were subgrouped into high- and low-risk groups as defined by the Australian Therapeutic Guidelines for animal bites. There were 160 cases of mammalian bite wounds included, with 143 (89.4%) patients grouped as high-risk and 17 (10.6%) patients identified as low-risk. High-risk features were delayed presentation > 8 hours (57 patients, 35.6%), bites to the head, hand or face (113 patients, 70.6%), and puncture wounds unable to be adequately debrided (74 patients, 46.3%). There was a significant association with delayed presentation of more than eight hours and clinically established infection [OR 36.2; 95% CI: 12.6-103.6; P < 0.001]. Prescriptions for antibiotics that adhered to current guidelines occurred in 99 (61.9%) cases. This study highlights variability in antibiotic prescription practice among clinicians and the need for ongoing education on antibiotic stewardship. Intervention strategies, including ongoing education, are indicated to improve adherence to antibiotic guidelines. Copyright © 2015 Elsevier Ltd. All rights reserved.

Epidemiological characteristics, hospital course and outcome of snakebite victims in West Texas.

PubMed

Abbey, James M; Jaffar, Nabil A; Abugrara, Hazem L; Nazim, Muhammad; Smalligan, Roger D; Khasawneh, Faisal A

2015-01-01

Numerous snakebites are reported every spring and summer in the United States especially in the Southwestern part of the country. This is usually associated with significant morbidity but fatalities are rare. Most victims are male and the majority of bites are on the extremities. A search for all cases coded with a discharge diagnosis of snakebite injury revealed 90 patients admitted to Northwest Texas Hospital, the trauma center in Amarillo, Texas, between January 2002 and December 2012. These charts were retrospectively reviewed and data extracted including patient demographics, severity of snakebite, treatment given, and ultimate outcome. Ninety patients were admitted to the hospital due to snakebite. It was a rattlesnake in 83 cases. The mean age of the victims was 29.7 years and 74 of them were male. Fifty-one bites were on the upper extremities, thirty-eight bites were on the lower extremities and one bite was on the abdominal wall. About 95% of the lower extremity bites were moderate or severe compared to 74.5% of the upper extremity bites, Cramer's coefficient 0.3, p=0.02. Thirty-one patients had complications and twenty patients required surgical intervention. Eighty-eight patients received a median of 10 vials of antivenin that was well tolerated. Median hospital length of stay was 3 days. None of the patients died. Rattlesnake bites cause significant morbidity although mortality is rare. Early administration of antivenin and appropriate supportive measures and monitoring for complications with surgical intervention when needed leads to improved patient outcomes.

Association between allergic rhinitis, bottle feeding, non‐nutritive sucking habits, and malocclusion in the primary dentition

PubMed Central

Vázquez‐Nava, F; Quezada‐Castillo, J A; Oviedo‐Treviño, S; Saldivar‐González, A H; Sánchez‐Nuncio, H R; Beltrán‐Guzmán, F J; Vázquez‐Rodríguez, E M

2006-01-01

Aim To determine the association between allergic rhinitis, bottle feeding, non‐nutritive sucking habits, and malocclusion in the primary dentition. Methods Data were collected on 1160 children aged 4–5 years, who had been longitudinally followed since the age of 4 months, when they were admitted to nurseries in a suburban area of Tampico–Madero, Mexico. Periodically, physical examinations were conducted and a questionnaire was given to their parents or tutors. Results Malocclusion was detected in 640 of the children (51.03% had anterior open bite and 7.5% had posterior cross‐bite). Allergic rhinitis alone (adjusted odds ratio = 2.87; 95% CI 1.57 to 5.25) or together with non‐nutritive sucking habits (adjusted odds ratio = 3.31; 95% CI 1.55 to 7.09) had an effect on anterior open bite. Bottle feeding alone (adjusted odds ratio = 1.95; 95% CI 1.07 to 3.54) or together with allergic rhinitis (adjusted odds ratio = 3.96; 95% CI 1.80 to 8.74) had an effect on posterior cross‐bite. Posterior cross‐bite was more frequent in children with allergic rhinitis and non‐nutritive sucking habits (10.4%). Conclusions Allergic rhinitis alone or together with non‐nutritive sucking habits is related to anterior open bite. Non‐nutritive sucking habits together with allergic rhinitis seem to be the most important factor for development of posterior open bite in children under the age of 5 years. PMID:16769710

Using Risk Group Profiles as a Lightweight Qualitative Approach for Intervention Development: An Example of Prevention of Tick Bites and Lyme Disease

PubMed Central

van Velsen, Lex; van Gemert - Pijnen, Julia EWC; Maat, Angelique; van Steenbergen, Jim E; Crutzen, Rik

2013-01-01

Background Many public health campaigns use a one-size-fits-all strategy to achieve their desired effect. Public health campaigns for tick bites and Lyme disease (LD) in many countries convey all relevant preventive measures to all members of the public. Although preventing tick bites (eg, by wearing protective clothing or using repellants) and checking for tick bites after visiting a risk area are effective and cost-efficient methods to prevent an individual from contracting a tick-borne disease, public compliance to these methods is low. Objective We aimed to identify the group of individuals within the general Dutch population that are at high risk of being bitten by a tick or developing LD and to describe their characteristics, knowledge, and perceptions. The incidence of patients visiting their general practitioner for tick bites and erythema migrans (the first sign of LD) has increased tremendously in the last decades in the Netherlands and other European countries; therefore, our efforts can be used to counter this troubling trend. Methods We conducted in-depth semi-structured interviews to identify individuals belonging to the average risk group. Participants were recruited in two ways. Patients who visited two municipal health services travel health clinics (one in a high-endemic area and one in a low-endemic area) were asked to participate. This resulted in 18 interviews. Further, parents were recruited using the convenience sampling method, which resulted in 7 interviews. We discontinued interviewing when the point of data saturation was reached. We analyzed the results immediately after each interview to identify the point of data saturation. Data saturation is when the new interviews provided no new information compared to the previous interviews. The interviews were transcribed and analyzed using inductive thematic analysis. Results We identified four groups at risk of being bitten by ticks and developing LD among the general Dutch population. The groups were as follows: (1) outdoor people that check for tick bites, (2) outdoor people that do not check for tick bites, (3) parents that check their children for tick bites, and (4) parents that do not check their children for tick bites. Previous experience with ticks or LD was the main denominator between the groups. Checking for tick bites is a more easily adopted measure than preventing tick bites. Therefore, for all groups, public health efforts in the future should primarily emphasize on the importance of checking for tick bites. Conclusions The lightweight qualitative approach presented in this paper is highly relevant in tailoring public health efforts toward specific groups. The profiles of members in each risk group and the motivations underlying the behaviors of the members in each risk group can be used to determine the features and content of a targeted communication strategy about ticks and LD. PMID:24172875

Do dogs bite without warning, or should we see it coming?

PubMed

2017-01-14

When dog bites occur, many owners will report the incident as being 'out of character' for the dog and as happening 'out of the blue'. But do dogs provide warning signs before biting and should owners and vets be able to see it coming? This question was explored in a session during the London Vet Show. Laura Honey reports. British Veterinary Association.

Using Negative Reinforcement to Increase Self-Feeding in a Child with Food Selectivity

ERIC Educational Resources Information Center

Vaz, Petula C. M.; Volkert, Valerie M.; Piazza, Cathleen C.

2011-01-01

We examined the effects of a negative reinforcement-based treatment on the self-feeding of 1 child with food selectivity by type and texture. Self-feeding increased when the child could choose to either self-feed 1 bite of a target food or be fed 1 bite of the target food and 5 bites of another food. Possible mechanisms that underlie the…

Using Teacher Prompts and Habit Reversal to Reduce Fingernail Biting in a Student with Attention Deficit Hyperactivity Disorder and a Mild Intellectual Disability

ERIC Educational Resources Information Center

Waller, Raymond J.; Kent, Susan; Johnson, Miriam E.

2007-01-01

Fingernail biting is a habit that is developed by numerous people, especially children and teenagers. Many clinicians believe that the habit of fingernail biting stems from nervousness or anxiety. Students, especially students with disabilities, can be easily distracted from instruction, can become the target of negative peer attention, and can…

A description of an ‘obesogenic’ eating style that promotes higher energy intake and is associated with greater adiposity in 4.5 year-old children: Results from the GUSTO cohort

PubMed Central

Fogel, Anna; Goh, Ai Ting; Fries, Lisa R.; Sadananthan, Suresh Anand; Velan, S. Sendhil; Michael, Navin; Tint, Mya Thway; Fortier, Marielle Valerie; Chan, Mei Jun; Toh, Jia Ying; Chong, Yap-Seng; Tan, Kok Hian; Yap, Fabian; Shek, Lynette P.; Meaney, Michael J.; Broekman, Birit F. P.; Lee, Yung Seng; Godfrey, Keith M.; Chong, Mary Foong Fong; Forde, Ciarán G.

2017-01-01

Recent findings confirm that faster eating rates support higher energy intakes within a meal and are associated with increased body weight and adiposity in children. The current study sought to identify the eating behaviours that underpin faster eating rates and energy intake in children, and to investigate their variations by weight status and other individual differences. Children (N=386) from the Growing Up in Singapore towards Healthy Outcomes (GUSTO) cohort took part in a video-recorded ad libitum lunch at 4.5 years of age to measure acute energy intake. Videos were coded for three eating behaviours (bites, chews and swallows) to derive a measure of eating rate (g/min) and measures of eating microstructure: eating rate (g/min), total oral exposure (minutes), average bite size (g/bite), chews per gram, oral exposure per bite (seconds), total bites and proportion of active to total mealtime. Children’s BMIs were calculated and a subset of children underwent MRI scanning to establish abdominal adiposity. Children were grouped into faster and slower eaters, and into healthy and overweight groups to compare their eating behaviours. Results demonstrate that faster eating rates were correlated with larger average bite size (r=0.55, p<0.001), fewer chews per gram (r=-0.71, p<0.001) and shorter oral exposure time per bite (r=-0.25, p<0.001), and with higher energy intakes (r=0.61, p<0.001). Children with overweight and higher adiposity had faster eating rates (p<0.01) and higher energy intakes (p<0.01), driven by larger bite sizes (p<0.05). Eating behaviours varied by sex, ethnicity and early feeding regimes, partially attributable to BMI. We propose that these behaviours describe an ‘obesogenic eating style’ that is characterised by faster eating rates, achieved through larger bites, reduced chewing and shorter oral exposure time. This obesogenic eating style supports acute energy intake within a meal and is more prevalent among, though not exclusive to, children with overweight. PMID:28213204

Clinico-epidemiology of arthropod stings and bites in primary hospitals of North Western province of Sri Lanka.

PubMed

Kularatne, Senanayake A M; Shahmy, Seyed; Rathnayake, Shantha S; Dawson, Andrew H

2018-03-06

Arthropod stinging and bites are common environmental hazards in Sri Lanka. However, their medical importance has not been fully evaluated yet. This study aims to study the burden, epidemiology, and outcome of stings and bites in primary hospitals in the Kurunegala district in North Western Province (NWP) of Sri Lanka. The study was conducted one year from 25th May 2013 to 25th May 2014. Details of all stings and bites admissions and their outcomes were retrospectively extracted from hospital records in all 44 primary hospitals in the district. There were 623 stings and bites with population incidence of 38/100,000 (95% CI 27-52). There were no deaths. Median age was 38 years (IQR: 19-53 years), and 351 (56%) were males. Most of stings and bites (75%) occurred in the daytime. Median time to hospital arrival was 55 minutes (IQR: 30 min to 2 h). The offending arthropods had been identified in 557 (89%) cases, of them, 357 (57%) were Hymenoptera (hornet and bees), 99 centipedes, 61 spiders and 40 scorpions. Local pain occurred in 346 (56%) cases - centipede 69 (70%), Scorpion 24 (60%), spider 36 (59%), Hymenoptera 187 (52%) and unidentified 30 (45%). Hymenoptera stings and spider bites occurred between 06 am to 12 noon, and scorpion stings and centipede bites mostly occurred between 06 pm to 12 midnight. Mild, moderate to severe anaphylaxis reactions occurred in 173 (28%) patients including 110 Hymenoptera stings - mild 39, moderate 62 and severe 9. From primary hospitals, 53(9%) cases had been transferred to tertiary care units for further management. Of them, 41 cases were Hymenoptera stings and 24 (58%) of them had mild, moderate to severe anaphylaxis. In the entire group, 27% severe cases received adrenaline. The primary hospitals in NW province of Sri Lanka manage large numbers of arthropod stings and bites. These include Hymenoptera (hornet and bee), centipedes, spiders, and scorpions. Pain, swellings and anaphylactic reactions were the most common adverse effects.

Children using Day Nurseries' Facilities can be Associated with more Risk to Nonnutritive Sucking Habits.

PubMed

Alves, Fabiana Bt; Wambier, Denise S; Alvarez, Jenny Ha; da Rocha, José Cf; Kummer, Thais R; de Castro, Vanessa C; Cabral, Howard; Kozlowski, Vitoldo A

2016-09-01

This study evaluated the expression of nonnutritive sucking habits and the presence of malocclusion in children using day nurseries' facilities. The 195 children (7-40 months) attending 18 public day nurseries were evaluated clinically in Ponta Grossa, Brazil. Statistical package software was used for descriptive, univariate, bivariate, and multiple logistic regressions of the data about the socioeconomic condition, educational family status, malocclusions, and prevalence of nonnutritive sucking habits among the children. The pacifier users had a statistically significant, explanatory association with open bite [odds ratio (OR) = 10.97; 95% confidence interval (CI): 4.95, 24.31; p < 0.0001]. The children older than 25 months had more open bite than younger children (OR = 6.07; 95% CI: 2.81, 13.11; p < 0.0001). Of the children examined, 35.4% had an anterior open bite, 0.51% had posterior cross-bite, and 1.03% showed finger-sucking habits. A high frequency of pacifier-sucking habits was found (52%), with a significant association between this habit and anterior open bite (p < 0.0001, OR = 7.49; 95% CI: 3.71, 15.15). The 126 children without open bite (36.5%) were pacifier users. There was suggestive, though nonsignificant, evidence of a difference in pacifier use by gender (males, 34%; females, 46%; p = 0.07). The 69 children with open bite (81.16%) were pacifier users and (18.84%) nonusers. The boys showed a slightly greater association with open bite (OR = 21.33; 95% CI: 6.12, 74.40; p < 0.0001) than girls (OR = 5.03; 95% CI: 1.26, 20.00; p = 0.02) in the age group of 25 to 40 months; however, it was not observed in younger children. Pacifier use is a predictor for open bite in children from the lower socioeconomic classes using day nurseries' facilities. The parents, guardians, and caregivers working in public day nurseries should be advised to monitor nonnutritive sucking habits in order to avoid or minimize the occurrence of malocclusion. It demonstrates that the permanence of the children in day nurseries may be linked with deleterious oral habits, and it discusses strategies to minimize the occurrence of alterations in the normal occlusion.

Ionospheric climatology at Africa EIA trough stations during descending phase of sunspot cycle 22

NASA Astrophysics Data System (ADS)

Adebesin, B. O.; Rabiu, A. B.; Bolaji, O. S.; Adeniyi, J. O.; Amory-Mazaudier, C.

2018-07-01

The African equatorial ionospheric climatology during the descending phase of sunspot-cycle 22 (spanning 1992-1996) was investigated using 3 ionosondes located at Dakar (14.70 N, 342.60 E), Ouagadougou (12.420 N, 358.60 E), and Korhogo (9.510 N, 354.40 E). The variations in the virtual height of the F-layer (h'F), maximum electron density (NmF2), vertical plasma drift (Vp) and zonal electric field (Ey) were presented. Significant decrease in the NmF2 amplitude compared to h'F in all of the stations during the descending period is obvious. While NmF2 magnitude maximizes/minimizes during the E-seasons/J-season, h'F attained highest/lowest altitude in J-season/D-season for all stations. D-season anomaly was evident in NmF2 at all stations. For any season, the intensity (Ibt) of NmF2 noon-bite-out is highest at Dakar owning to fountain effect and maximizes in March-E season. Stations across the EIA trough show nearly coherence ionospheric climatology characteristics whose difference is of latitudinal origin. Hemispheric dependence in NmF2 is obvious, with difference more significant during high-solar activity and closes with decreasing solar activity. The variability in the plasma drift during the entire phase is suggested to emanate from solar flux variations, and additionally from enhanced leakage of electric fields from high-to low-latitudes. Existing African regional model of evening/nightttime pre-reversal plasma drift/sunspot number (PREpeak/R) relationship compares well with experimental observations at all stations with slight over-estimation. The correlation/root-mean-square-deviation (RMSdev) pair between the model and observed Vp during the descending phase recorded 94.9%/0.756, 92.4%/1.526, and 79.1%/3.612 at Korhogo, Ouagadougou and Dakar respectively. The Ey/h'F and Ey/NmF2 relationships suggest that zonal electric field is more active in the lifting of h'F and suppression of NmF2 during high- and moderate-solar activities when compared with low-solar activity. This is the first work to show higher bite-out at the equatorial northern-station (Dakar) than southern-station (Korhogo) using ionosonde data.

Biological production of ethanol from coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Due to the abundant supply of coal in the United States, significant research efforts have occurred over the past 15 years concerning the conversion of coal to liquid fuels. Researchers at the University of Arkansas have concentrated on a biological approach to coal liquefaction, starting with coal-derived synthesis gas as the raw material. Synthesis gas, a mixture of CO, H[sub 2], CO[sub 2], CH[sub 4] and sulfur gases, is first produced using traditional gasification techniques. The CO, CO[sub 2] and H[sub 2] are then converted to ethanol using a bacterial culture of Clostridium 1jungdahlii. Ethanol is the desired product ifmore » the resultant product stream is to be used as a liquid fuel. However, under normal operating conditions, the wild strain'' produces acetate in favor of ethanol in conjunction with growth in a 20:1 molar ratio. Research was performed to determine the conditions necessary to maximize not only the ratio of ethanol to acetate, but also to maximize the concentration of ethanol resulting in the product stream.« less

Biological production of ethanol from coal. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Due to the abundant supply of coal in the United States, significant research efforts have occurred over the past 15 years concerning the conversion of coal to liquid fuels. Researchers at the University of Arkansas have concentrated on a biological approach to coal liquefaction, starting with coal-derived synthesis gas as the raw material. Synthesis gas, a mixture of CO, H{sub 2}, CO{sub 2}, CH{sub 4} and sulfur gases, is first produced using traditional gasification techniques. The CO, CO{sub 2} and H{sub 2} are then converted to ethanol using a bacterial culture of Clostridium 1jungdahlii. Ethanol is the desired product ifmore » the resultant product stream is to be used as a liquid fuel. However, under normal operating conditions, the ``wild strain`` produces acetate in favor of ethanol in conjunction with growth in a 20:1 molar ratio. Research was performed to determine the conditions necessary to maximize not only the ratio of ethanol to acetate, but also to maximize the concentration of ethanol resulting in the product stream.« less

Anterior open bite treated with myofunctional therapy and palatal crib.

PubMed

Asiry, Moshabab A

2015-03-01

This case report demonstrates the treatment effects of palatal crib combined with the myofunctional therapy in a child with anterior open bite (AOB) due to thumb sucking and habitual anterior and low tongue position. The patient, an 11-year-old boy, had an anterior open bite and flared and spaced upper and lower incisors. Palatal cribs in conjunction with myofunctional therapy were used to discourage sucking habit and to adapt normal tongue position. Successful correction of the AOB with adequate overjet and overbite were achieved with total treatment time of 7 months. The importance of myofunctional therapy in adopting normal tongue position and in maintaining the stability of open bite correction is emphasized.

Amelogenesis imperfecta and anterior open bite: Etiological, classification, clinical and management interrelationships

PubMed Central

Alachioti, Xanthippi Sofia; Dimopoulou, Eleni; Vlasakidou, Anatoli; Athanasiou, Athanasios E

2014-01-01

Although amelogenesis imperfecta is not a common dental pathological condition, its etiological, classification, clinical and management aspects have been addressed extensively in the scientific literature. Of special clinical consideration is the frequent co-existence of amelogenesis imperfecta with the anterior open bite. This paper provides an updated review on amelogenesis imperfecta as well as anterior open bite, in general, and documents the association of these two separate entities, in particular. Diagnosis and treatment of amelogenesis imperfecta patients presenting also with anterior open bite require a lengthy, comprehensive and multidisciplinary approach, which should aim to successfully address all dental, occlusal, developmental, skeletal and soft tissue problems associated with these two serious clinical conditions. PMID:24987656

Long-term outcome in a patient with a dentoskeletal open-bite malocclusion treated without extraction.

PubMed

Celli, Daniel; Gasperoni, Enrico; Deli, Roberto

2007-01-01

This case report describes the treatment of a patient with a Class II malocclusion with an anterior open bite. The patient, a girl 16 years of age, had a significant anteroposterior discrepancy and a high-angle tendency. Her face was convex, with competent lips. Intraorally she had an anterior open bite of 3 mm, space in the mandibular arch, and an overjet of 2 mm. High-pull headgear, anterior intermaxillary elastics, and appropriate wire bending were used to close the bite and to correct the anteroposterior dental relationship. Modification of a tongue thrust habit helped to correct this significant malocclusion and provided stability at 11 years posttreatment.

Orthodontic Treatment Timing and Modalities in Anterior Open Bite: Case Series Study

PubMed Central

Al Hamadi, Wisam; Saleh, Fayez; Kaddouha, Mohamad

2017-01-01

Objective: The purpose of this study was to present early and adult cases of anterior open bite that were treated efficiently using different treatment approaches and mechanics. Materials and Methods: Five patients of different age groups (from 7 to 27 years), suffering from a clear Anterior open bite deformity, were properly diagnosed and relevant treatment modality for each was selected. Results: Positive overbite was efficiently achieved for all patients. Conclusion: Patient compliance is a key factor in using removable habit breakers. However, fixed palatal crib gave the same results but in shorter time. Anterior open bite of skeletal components should be thoroughly evaluated before selecting camouflage or orthognathic surgery treatment modality. PMID:29299074

Amelogenesis imperfecta and anterior open bite: Etiological, classification, clinical and management interrelationships.

PubMed

Alachioti, Xanthippi Sofia; Dimopoulou, Eleni; Vlasakidou, Anatoli; Athanasiou, Athanasios E

2014-01-01

Although amelogenesis imperfecta is not a common dental pathological condition, its etiological, classification, clinical and management aspects have been addressed extensively in the scientific literature. Of special clinical consideration is the frequent co-existence of amelogenesis imperfecta with the anterior open bite. This paper provides an updated review on amelogenesis imperfecta as well as anterior open bite, in general, and documents the association of these two separate entities, in particular. Diagnosis and treatment of amelogenesis imperfecta patients presenting also with anterior open bite require a lengthy, comprehensive and multidisciplinary approach, which should aim to successfully address all dental, occlusal, developmental, skeletal and soft tissue problems associated with these two serious clinical conditions.

Phantom bite: a real or a phantom diagnosis? A case report.

PubMed

Sutter, Ben A

2017-01-01

This case report describes computer-guided occlusal therapy in a patient who met the unified diagnostic criteria for phantom bite. After a review of the patient's medical history, along with a diagnostic work-up that included cone beam computed tomography, temporomandibular joint vibration analysis, and digital occlusal analysis, problematic dental components were discovered (including prolonged disclusion time and imbalanced bite force). A digital occlusal analyzer evaluated the patient's occlusion and systematically guided the necessary changes. After reduction of the disclusion time and correction of the occlusal force imbalance, the patient reported significant improvement in comfort. The results suggest that phantom bite could be an abnormal occlusal condition and not a psychological or neurologic somatoform disorder.

[Identification of a murderer on the basis of a biting pattern on body of the victim].

PubMed

Zaba, Czesław; Lorkiewicz-Muszyńska, Dorota; Glapiński, Mariusz; Smoluch, Krzysztof; Swiderski, Paweł

2010-01-01

The authors present a case of identification of a a murderer on the basis of his dentition pattern, reflected by a biting wound on the breast of the victim. The case is exceptional not only from the viewpoint of the authors, but also in view of very sporadic reports on this subject in forensic literature. Cases of biting by humans are not frequent in the forensic/ medical practice, and instances of identification of the perpetrator by his dental pattern reflected in the biting wound are very rare. In Poland, such problems have been the domain of mainly criminologists and only occasionally of forensic medics in collaboration with dentists and anthropologists. Due to the very low number of such cases in Poland, no experts in the matter are available. For this reason, we deemed it purposeful to present respective investigative principles and techniques for identification of a human perpetrator on the basis of the dental pattern reflected in a biting wound on the victim's body.

Tail biting in pigs--causes and management intervention strategies to reduce the behavioural disorder. A review.

PubMed

Sonoda, Lilia Thays; Fels, Michaela; Oczak, Maciej; Vranken, Erik; Ismayilova, Gunel; Guarino, Marcella; Viazzi, Stefano; Bahr, Claudia; Berckmans, Daniel; Hartung, Jörg

2013-01-01

One of the largest animal welfare problems in modern pig production is tail biting. This abnormal behaviour compromises the well-being of the animals, can seriously impair animal health and can cause considerable economic losses. Tail biting has a multifactorial origin and occurs mainly in fattening pigs. High stocking densities, poor environment and bad air quality are seen as important factors. However, it is presumed that a plurality of internal and external motivators in intensive pig production can trigger this behaviour which is not reported in sounders of wild boars. The aim of this review is to summarize the causes and the effects of tail biting in pigs and present management strategies that are likely to reduce its incidence. In particular, management strategies by applying Precision Livestock Farming (PLF) technologies to monitor and control the behaviour of the pigs may be suitable to detect the outbreaks of tail biting at an early stage so that counter measures can be taken in time.

Contrast enhancement of bite mark images using the grayscale mixer in ACR in Photoshop®.

PubMed

Evans, Sam; Noorbhai, Suzanne; Lawson, Zoe; Stacey-Jones, Seren; Carabott, Romina

2013-05-01

Enhanced images may improve bite mark edge definition, assisting forensic analysis. Current contrast enhancement involves color extraction, viewing layered images by channel. A novel technique, producing a single enhanced image using the grayscale mix panel within Adobe Camera Raw®, has been developed and assessed here, allowing adjustments of multiple color channels simultaneously. Stage 1 measured RGB values in 72 versions of a color chart image; eight sliders in Photoshop® were adjusted at 25% intervals, all corresponding colors affected. Stage 2 used a bite mark image, and found only red, orange, and yellow sliders had discernable effects. Stage 3 assessed modality preference between color, grayscale, and enhanced images; on average, the 22 survey participants chose the enhanced image as better defined for nine out of 10 bite marks. The study has shown potential benefits for this new technique. However, further research is needed before use in the analysis of bite marks. © 2013 American Academy of Forensic Sciences.

How informative are case studies of spider bites in the medical literature?

PubMed

Stuber, Marielle; Nentwig, Wolfgang

2016-05-01

We analyzed the reliability and information content of 134 medical case studies on spider bites, published in 91 journal articles. Overall, we found that only 22% of these studies fulfilled the criteria for a verified spider bite. This means that the majority of such case studies cannot be attributed to a given spider species and usually not even to a spider. Their scientific value is negligible, moreover, such publications are even dangerous because they suggest incorrect conclusions. Secondly, we found that such case studies usually do not follow an obvious structure and many details on the development of symptoms, therapy and healing process are widely lacking. So even for verified spider bites, the comparability of case studies is limited. We discuss the obvious failure of a reviewing process for case studies and give recommendations how to increase the currently low information content of medical case studies on spider bites. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Morphological and Morphometric Study of Bite Marks Caused by Mice (Mus Musculus) on Different Baits for Forensic Purposes.

PubMed

Toledo, Víctor A; Fonseca, Gabriel M; González, Paula A; Ibarra, Luis; Torres, Francisco J; Sáez, Pedro L

2017-03-01

In animal bites, the dental attributes can be fundamental in identifying the marks made by various species on different matrices. Although rodent bite marks have been studied in the context of postmortem interference, little research has used different baits to analyze these marks linking not only specific behavior patterns but also the possibility of structural damage. Twenty mice (Mus musculus) were exposed to different baits to study their bite marks in a controlled model. The known pattern of parallel and multiple grooves has been seen in all baits, but polyvinyl chloride and fiber-optic cable were significantly different between each other and the other baits. Some baits showed patterns of anchorage of the upper incisors and space between the lower incisors when gnawing. This technical note represents a novel model of analysis where veterinarians and/or dentists may be asked to give an opinion on alleged animal bite marks. © 2016 American Academy of Forensic Sciences.

EFFECTS OF SUGAR CONCENTRATION ON FECUNDITY, BITING BEHAVIOR AND SURVIVABILITY OF FEMALE AEDES (STEGOMYIA) ALBOPICTUS (SKUSE).

PubMed

Aiman, Muhammad; Kassim, Nur Faeza A; Jong, Zheng-Wei; Webb, Cameron E

2016-11-01

This study was conducted to better understand the effect of different sucrose concentrations on Aedes albopictus fecundity, biting behavior and survival. Laboratory strain Ae. albopictus females were raised at four different sucrose concentrations (10%, 30%, 50%, and 70%) and their fecundity, host biting on and survival rates were determined. Mosquitoes fed on high (50% or 70%) showed higher mean fecundity rate compared to those on low (10% or 30%) sucrose concentration, and had higher daily biting rate. On the other hand, mosquitoes fed on the low (10% or 30%) sucrose concentrations recorded higher survival rate. These results suggest female mosquitoes deficient in nutrient intake during sugar feeding may regain nutrients needed during blood feeding, whereas those fed on high sucrose concentration have high fecundity due to high biting rate but have low survivability due to low sucrose intake during sugar feeding. Thus, Ae. albopictus females have a capability to regulate their metabolic needs based on sugar nutrient availability.

Relationship between facial morphology, anterior open bite and non-nutritive sucking habits during the primary dentition stage

PubMed Central

Fialho, Melissa Proença Nogueira; Pinzan-Vercelino, Célia Regina Maio; Nogueira, Rodrigo Proença; Gurgel, Júlio de Araújo

2014-01-01

Introduction Non-nutritive sucking habits (NNSHs) can cause occlusal alterations, including anterior open bite (AOB). However, not all patients develop this malocclusion. Therefore, the emergence of AOB does not depend on deleterious habits, only. Objective Investigate a potential association between non-nutritive sucking habits (NNSHs), anterior open bite (AOB) and facial morphology (FM). Methods 176 children in the primary dentition stage were selected. Intra and extraoral clinical examinations were performed and the children's legal guardians were asked to respond to a questionnaire comprising issues related to non-nutritive sucking habits (NNSHs). Results A statistically significant relationship was found between non-nutritive sucking habits (NNSHs) and anterior open bite (AOB). However, no association was found between these factors and children's facial morphology (FM). Conclusions Non-nutritive sucking habits (NNSHs) during the primary dentition stage play a key role in determining anterior open bite (AOB) malocclusion regardless of patient's morphological facial pattern (FM). PMID:25162574

Incidence, pathology, and treatment of adder (Vipera berus L.) bites in man.

PubMed Central

Reading, C J

1996-01-01

A review of published reports on the incidence, pathology, and treatment of adder (Vipera berus) bites in man in the United Kingdom and Europe produced numerous case studies but little information about the impact od adders as a threat to public health. Adder bites in man are not uncommon (at least 44/year and probably more than 90/year in the United Kingdom) and, although they have been recorded for every month of the year between February and October, envenoming is most likely to occur during June, July, and August. Most adder bites are on the hand (51.6%) or foot (38.2%). The effects of adder bite envenoming are now know. Effective treatment protocols can reduce both the length of time victims spend in hospital and the morbidity in the affected areas: they have resulted in a decline in the death rate over the last 30 years, so that deaths are now rare. PMID:8894864

Envenoming by coral snakes (Micrurus) in Argentina, during the period between 1979-2003.

PubMed

de Roodt, Adolfo Rafael; De Titto, Ernesto; Dolab, Jorge Adrián; Chippaux, Jean-Philippe

2013-01-01

Envenomation by coral snakes (Micrurus sp.) is one of the most dangerous injuries in America and it is considered as a serious medical emergency, however bites by these snakes appear to be rare. We analyzed epidemiological data, clinical signs and antivenom use in Argentina during the period between 1979-2003. During this period of study 46 non-fatal Micrurus bites were reported. The majority of cases were men from 31 to 40 years old. Bites occurred primarily in spring and summer. Most cases were reported from the northeast and northwest provinces of the country. The bites were mostly located on hands or feet and occurred mostly during agricultural activities and so mainly involved farmers. Only four cases occurred as a result of handling snakes. The median time it took for antivenom to be administrated was 60 minutes after the bite, and the median number of vials applied was 2. Local pain was mentioned and edema was reported in 41% of patients. All patients recovered without sequelae. This study showed a low incidence of Micrurus bites and low severity of envenomation. However, although no deaths have been reported during the last 30 years, given the toxicity of the venom of Micrurus snakes, the risk of severe envenomation should be considered.

DNA barcoding of human-biting black flies (Diptera: Simuliidae) in Thailand.

PubMed

Pramual, Pairot; Thaijarern, Jiraporn; Wongpakam, Komgrit

2016-12-01

Black flies (Diptera: Simuliidae) are important insect vectors and pests of humans and animals. Accurate identification, therefore, is important for control and management. In this study, we used mitochondrial cytochrome oxidase I (COI) barcoding sequences to test the efficiency of species identification for the human-biting black flies in Thailand. We used human-biting specimens because they enabled us to link information with previous studies involving the immature stages. Three black fly taxa, Simulium nodosum, S. nigrogilvum and S. doipuiense complex, were collected. The S. doipuiense complex was confirmed for the first time as having human-biting habits. The COI sequences revealed considerable genetic diversity in all three species. Comparisons to a COI sequence library of black flies in Thailand and in a public database indicated a high efficiency for specimen identification for S. nodosum and S. nigrogilvum, but this method was not successful for the S. doipuiense complex. Phylogenetic analyses revealed two divergent lineages in the S. doipuiense complex. Human-biting specimens formed a separate clade from other members of this complex. The results are consistent with the Barcoding Index Number System (BINs) analysis that found six BINs in the S. doipuiense complex. Further taxonomic work is needed to clarify the species status of these human-biting specimens. Copyright © 2016 Elsevier B.V. All rights reserved.

Clinical Features of Idiopathic Parotid Pain Triggered by the First Bite in Japanese Patients with Type 2 Diabetes: A Case Study of Nine Patients.

PubMed

Chiba, Masatoshi; Hirotani, Hiroaki; Takahashi, Tetsu

2018-01-01

First bite syndrome, characterized by pain in the parotid region after the first bite of each meal, predominantly develops in patients who have had head and neck surgery. Idiopathic parotid pain (IPP) that mimics first bite syndrome may present in patients without a history of surgery or evidence of an underlying tumor, but its clinical features are unclear. This study characterized the clinical characteristics of IPP in patients with diabetes. A retrospective case review involving the clinical findings and pain characteristics of nine patients with IPP and diabetes who presented to our department between 2013 and 2016. All the patients were men diagnosed with type 2 diabetes (median age, 43 years). IPP developed unilaterally in seven patients and bilaterally in two. The median intensity of the first bite pain was 8 on a numerical rating scale of 0-10. The trigger factor was gustatory stimuli, and the trigger area was the posterior section of the tongue. Postprandial pain occurred within 1-10 min after meals in six patients. IPP may be considered a separate disorder, in which the pain characteristics are similar to those of first bite syndrome but the clinical features and pathophysiology are different.

Clinical Features of Idiopathic Parotid Pain Triggered by the First Bite in Japanese Patients with Type 2 Diabetes: A Case Study of Nine Patients

PubMed Central

Hirotani, Hiroaki; Takahashi, Tetsu

2018-01-01

Objective First bite syndrome, characterized by pain in the parotid region after the first bite of each meal, predominantly develops in patients who have had head and neck surgery. Idiopathic parotid pain (IPP) that mimics first bite syndrome may present in patients without a history of surgery or evidence of an underlying tumor, but its clinical features are unclear. This study characterized the clinical characteristics of IPP in patients with diabetes. Study Design A retrospective case review involving the clinical findings and pain characteristics of nine patients with IPP and diabetes who presented to our department between 2013 and 2016. Results All the patients were men diagnosed with type 2 diabetes (median age, 43 years). IPP developed unilaterally in seven patients and bilaterally in two. The median intensity of the first bite pain was 8 on a numerical rating scale of 0–10. The trigger factor was gustatory stimuli, and the trigger area was the posterior section of the tongue. Postprandial pain occurred within 1–10 min after meals in six patients. Conclusions IPP may be considered a separate disorder, in which the pain characteristics are similar to those of first bite syndrome but the clinical features and pathophysiology are different. PMID:29796314

Biting and chewing in overdentures, full dentures, and natural dentitions.

PubMed

Fontijn-Tekamp, F A; Slagter, A P; Van Der Bilt, A; Van 'T Hof, M A; Witter, D J; Kalk, W; Jansen, J A

2000-07-01

It has been suggested that the provision of dental implants can improve the oral function of subjects with severely resorbed mandibles, possibly restoring function to the level experienced by satisfied wearers of conventional complete dentures. Nevertheless, a quantitative comparison has never been made and can be drawn from the literature only with difficulty, since studies differ greatly in methodology. To make such a comparison, we measured bite force and chewing efficiency by using identical methods in subjects with overdentures, complete full dentures, and natural dentitions. Our results indicated that bite forces achieved with overdentures on dental implants were between those achieved with artificial and natural dentitions. Chewing efficiency was significantly greater than that of subjects with full dentures (low mandible), but was still lower than that of subjects with full dentures (high mandible) and overdentures on bare roots. Differences in the height of the mandible revealed significant differences in chewing efficiency between the two full-denture groups. Furthermore, subjects with a shortened dental arch exerted bite forces similar to those of subjects with a complete-natural dentition, but their chewing efficiency was limited due to the reduced occlusal area. For all groups combined, a significant correlation was found between maximum bite force and chewing efficiency. Nearly half of the variation in chewing efficiency was explained by bite force alone.

Lessons Learned From the Implementation of Brighter Bites: A Food Co-op to Increase Access to Fruits and Vegetables and Nutrition Education Among Low-Income Children and Their Families.

PubMed

Sharma, Shreela V; Chow, Joanne; Pomeroy, Michael; Raber, Margaret; Salako, David; Markham, Christine

2017-04-01

Food co-op models have gained popularity as a mechanism for offering affordable, quality produce. We describe the challenges, successes, and lessons learned from implementation of a school-based program using a food co-op model combined with nutrition education to improve access to and intake of fresh fruits and vegetables among low-income children and their families. Brighter Bites is a 16-week intervention comprising of fresh produce deliveries, recipe demonstrations, and nutrition education. A mixed-methods approach was used comprising survey and focus group data collected from Brighter Bites staff, parents, and teachers. Descriptive statistics and frequencies were computed for the survey data collected. Brighter Bites was implemented across 9 schools, serving a total of 1530 predominantly low-income families in the 2013-2014 school year. Brighter Bites distributed an average 60.2 servings of fresh fruits and vegetables per family per week. Lessons learned included the importance of leveraging existing infrastructure of food banks and schools to implement the program, early school and parent engagement, and incorporating strategies to track and optimize engagement. Clear expectations and reliable partnerships are keys to the delivery of the Brighter Bites program. © 2017, American School Health Association.

Helical tomotherapy setup variations in canine nasal tumor patients immobilized with a bite block.

PubMed

Kubicek, Lyndsay N; Seo, Songwon; Chappell, Richard J; Jeraj, Robert; Forrest, Lisa J

2012-01-01

The purpose of our study was to compare setup variation in four degrees of freedom (vertical, longitudinal, lateral, and roll) between canine nasal tumor patients immobilized with a mattress and bite block, versus a mattress alone. Our secondary aim was to define a clinical target volume (CTV) to planning target volume (PTV) expansion margin based on our mean systematic error values associated with nasal tumor patients immobilized by a mattress and bite block. We evaluated six parameters for setup corrections: systematic error, random error, patient-patient variation in systematic errors, the magnitude of patient-specific random errors (root mean square [RMS]), distance error, and the variation of setup corrections from zero shift. The variations in all parameters were statistically smaller in the group immobilized by a mattress and bite block. The mean setup corrections in the mattress and bite block group ranged from 0.91 mm to 1.59 mm for the translational errors and 0.5°. Although most veterinary radiation facilities do not have access to Image-guided radiotherapy (IGRT), we identified a need for more rigid fixation, established the value of adding IGRT to veterinary radiation therapy, and define the CTV-PTV setup error margin for canine nasal tumor patients immobilized in a mattress and bite block. © 2012 Veterinary Radiology & Ultrasound.

Snake Bite in South Asia: A Review

PubMed Central

Alirol, Emilie; Sharma, Sanjib Kumar; Bawaskar, Himmatrao Saluba; Kuch, Ulrich; Chappuis, François

2010-01-01

Snake bite is one of the most neglected public health issues in poor rural communities living in the tropics. Because of serious misreporting, the true worldwide burden of snake bite is not known. South Asia is the world's most heavily affected region, due to its high population density, widespread agricultural activities, numerous venomous snake species and lack of functional snake bite control programs. Despite increasing knowledge of snake venoms' composition and mode of action, good understanding of clinical features of envenoming and sufficient production of antivenom by Indian manufacturers, snake bite management remains unsatisfactory in this region. Field diagnostic tests for snake species identification do not exist and treatment mainly relies on the administration of antivenoms that do not cover all of the important venomous snakes of the region. Care-givers need better training and supervision, and national guidelines should be fed by evidence-based data generated by well-designed research studies. Poorly informed rural populations often apply inappropriate first-aid measures and vital time is lost before the victim is transported to a treatment centre, where cost of treatment can constitute an additional hurdle. The deficiency of snake bite management in South Asia is multi-causal and requires joint collaborative efforts from researchers, antivenom manufacturers, policy makers, public health authorities and international funders. PMID:20126271

Bite mark documentation and analysis: the forensic 3D/CAD supported photogrammetry approach.

PubMed

Thali, M J; Braun, M; Markwalder, Th H; Brueschweiler, W; Zollinger, U; Malik, Naseem J; Yen, K; Dirnhofer, R

2003-08-12

Bite mark identification is based on the individuality of a dentition, which is used to match a bite mark to a suspected perpetrator. This matching is based on a tooth-by-tooth and arch-to-arch comparison utilising parameters of size, shape and alignment. The most common method used to analyse bite mark are carried out in 2D space. That means that the 3D information is preserved only two dimensionally with distortions. This paper presents a new 3D documentation, analysis and visualisation approach based on forensic 3D/CAD supported photogrammetry (FPHG) and the use of a 3D surface scanner. Our photogrammetric approach and the used visualisation method is, to the best to our knowledge, the first 3D approach for bite mark analysis in an actual case. The documentation has no distortion artifacts as can be found with standard photography. All the data are documented with a metric 3D measurement, orientation and subsequent analysis in 3D space. Beside the metrical analysis between bite mark and cast, it is possible using our method to utilise the topographical 3D feature of each individual tooth. This means that the 3D features of the biting surfaces and edges of each teeth are respected which is--as shown in our case--very important especially in the front teeth which have the first contact to the skin. Based upon the 3D detailed representation of the cast with the 3D topographic characteristics of the teeth, the interaction with the 3D documented skin can be visualised and analysed on the computer screen.

Functional compartmentalization of the human superficial masseter muscle.

PubMed

Guzmán-Venegas, Rodrigo A; Biotti Picand, Jorge L; de la Rosa, Francisco J Berral

2015-01-01

Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle's motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20-60% MVBF).

Functional Compartmentalization of the Human Superficial Masseter Muscle

PubMed Central

Guzmán-Venegas, Rodrigo A.; Biotti Picand, Jorge L.; de la Rosa, Francisco J. Berral

2015-01-01

Some muscles have demonstrated a differential recruitment of their motor units in relation to their location and the nature of the motor task performed; this involves functional compartmentalization. There is little evidence that demonstrates the presence of a compartmentalization of the superficial masseter muscle during biting. The aim of this study was to describe the topographic distribution of the activity of the superficial masseter (SM) muscle’s motor units using high-density surface electromyography (EMGs) at different bite force levels. Twenty healthy natural dentate participants (men: 4; women: 16; age 20±2 years; mass: 60±12 kg, height: 163±7 cm) were selected from 316 volunteers and included in this study. Using a gnathodynamometer, bites from 20 to 100% maximum voluntary bite force (MVBF) were randomly requested. Using a two-dimensional grid (four columns, six electrodes) located on the dominant SM, EMGs in the anterior, middle-anterior, middle-posterior and posterior portions were simultaneously recorded. In bite ranges from 20 to 60% MVBF, the EMG activity was higher in the anterior than in the posterior portion (p-value = 0.001).The center of mass of the EMG activity was displaced towards the posterior part when bite force increased (p-value = 0.001). The topographic distribution of EMGs was more homogeneous at high levels of MVBF (p-value = 0.001). The results of this study show that the superficial masseter is organized into three functional compartments: an anterior, a middle and a posterior compartment. However, this compartmentalization is only seen at low levels of bite force (20–60% MVBF). PMID:25692977

[Prevalence of reactions secundary to mosquito bites Aedes aegypti at en el Regional Center of Allergy and Clinical Immunology, University Hospital, de Monterrey, Nuevo Leon].

PubMed

González Diaz, Sandra Nora; Cruz, Alfredo Arias; Sedó Mejía, Giovanni A; Rojas Lozano, Antonio A; Valenzuela, Enrique Avitia; Vidaurri Ojeda, Alma C

2010-01-01

although systemic reactions resulting from hymenoptera stings have been studied extensively, the prevalence of allergic reactions to mosquitoes is unknown. to investigate the prevalence of allergic reactions to Aedes aegypti bites in patients seeking treatment at the Allergy and Clinical Immunology Regional Center of Jose E Gonzalez University Hospital in Monterrey, Mexico. we carried out a cross-sectional, descriptive study that included patients receiving skin tests for aeroallergens; skin sensitivity to mosquito bites was also tested. A questionnaire was used to obtain information about previous allergic reactions to mosquito bites. a total of 482 patients between 2 and 60 years of age were included; 53% were female, 407 (84.4%) had a history of local reactions to mosquito bites. Twelve patients (2.4%) stated a history of large local reaction; three (0.6%) of them with a positive skin prick test, one (0.2%) of those had systemic reaction history to mosquito. Eighty five (17.6%) patients had a positive mosquito skin test and 307 (63.6%) had a positive skin test for at least one aeroallergen. Seventy-eight (91.7%) of the 85 patients with a positive mosquito skin test had a history of local skin reactions to mosquito bite (odds ratio: 2.303 [confidence interval (CI) 1.037-5.10]. There was no statistically significance association between allergic diseases and mosquito allergy. adverse reactions and allergic reactions to mosquito bites occur frequently. However mosquito allergy is low. Further studies are required to determine the prevalence of mosquito allergy in the general population.

Developing a musculoskeletal model of the primate skull: predicting muscle activations, bite force, and joint reaction forces using multibody dynamics analysis and advanced optimisation methods.

PubMed

Shi, Junfen; Curtis, Neil; Fitton, Laura C; O'Higgins, Paul; Fagan, Michael J

2012-10-07

An accurate, dynamic, functional model of the skull that can be used to predict muscle forces, bite forces, and joint reaction forces would have many uses across a broad range of disciplines. One major issue however with musculoskeletal analyses is that of muscle activation pattern indeterminacy. A very large number of possible muscle force combinations will satisfy a particular functional task. This makes predicting physiological muscle recruitment patterns difficult. Here we describe in detail the process of development of a complex multibody computer model of a primate skull (Macaca fascicularis), that aims to predict muscle recruitment patterns during biting. Using optimisation criteria based on minimisation of muscle stress we predict working to balancing side muscle force ratios, peak bite forces, and joint reaction forces during unilateral biting. Validation of such models is problematic; however we have shown comparable working to balancing muscle activity and TMJ reaction ratios during biting to those observed in vivo and that peak predicted bite forces compare well to published experimental data. To our knowledge the complexity of the musculoskeletal model is greater than any previously reported for a primate. This complexity, when compared to more simple representations provides more nuanced insights into the functioning of masticatory muscles. Thus, we have shown muscle activity to vary throughout individual muscle groups, which enables them to function optimally during specific masticatory tasks. This model will be utilised in future studies into the functioning of the masticatory apparatus. Copyright © 2012 Elsevier Ltd. All rights reserved.

Open bite as a risk factor for orthodontic root resorption.

PubMed

Motokawa, Masahide; Terao, Akiko; Kaku, Masato; Kawata, Toshitsugu; Gonzales, Carmen; Darendeliler, M Ali; Tanne, Kazuo

2013-12-01

The purpose of the present study was to clarify the prevalence and degree of root resorption induced by orthodontic treatment in patients with and without open bite. One hundred and eleven patients treated with multibracket appliances were retrospectively selected from the patients and divided into non-open bite (NOB) and open bite (OB) groups. The severity of root resorption and the root shape were classified into five groups on periapical radiographs before and after treatment. Moreover, only in the OB group, all teeth were sub-divided into functional and hypofunctional ones that are occluding and non-occluding. As the results of multiple linear regression analysis of patient characteristics and clinical variables with the number of overall root resorption, the independent variables that were found to contribute significantly to root resorption were bite and abnormal root shape. The prevalences of root resorption evaluated in the number of patients were significantly higher in OB group than in NOB group, and those in the number of teeth were significantly higher in OB group than in NOB group, in particular anterior and premolar teeth. The prevalence of resorbed teeth with abnormal root shapes was also significantly higher in OB group than in NOB group. On the other hand, in OB group, the prevalences of root resorption and teeth with abnormal root shape were significantly greater in hypofunctional teeth than in normal functional teeth. There are more teeth with root resorption and abnormal root shape in open bite cases than in normal bite cases, and more teeth with abnormal root shapes and root resorption in hypofunctional teeth than in functional teeth.

Sensationalistic journalism and tales of snakebite: are rattlesnakes rapidly evolving more toxic venom?

PubMed

Hayes, William K; Mackessy, Stephen P

2010-03-01

Recent reports in the lay press have suggested that bites by rattlesnakes in the last several years have been more severe than those in the past. The explanation, often citing physicians, is that rattlesnakes are evolving more toxic venom, perhaps in response to anthropogenic causes. We suggest that other explanations are more parsimonious, including factors dependent on the snake and factors associated with the bite victim's response to envenomation. Although bites could become more severe from an increased proportion of bites from larger or more provoked snakes (ie, more venom injected), the venom itself evolves much too slowly to explain the severe symptoms occasionally seen. Increased snakebite severity could also result from a number of demographic changes in the victim profile, including age and body size, behavior toward the snake (provocation), anatomical site of bite, clothing, and general health including asthma prevalence and sensitivity to foreign antigens. Clinical management of bites also changes perpetually, rendering comparisons of snakebite severity over time tenuous. Clearly, careful study taking into consideration many factors will be essential to document temporal changes in snakebite severity or venom toxicity. Presently, no published evidence for these changes exists. The sensationalistic coverage of these atypical bites and accompanying speculation is highly misleading and can produce many detrimental results, such as inappropriate fear of the outdoors and snakes, and distraction from proven snakebite management needs, including a consistent supply of antivenom, adequate health care, and training. We urge healthcare providers to avoid propagating misinformation about snakes and snakebites. Copyright (c) 2010 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

Three-dimensional imaging of human cutaneous forearm bite marks in human volunteers over a 4 day period.

PubMed

de Sainte Croix, M M; Gauld, D; Forgie, A H; Lowe, R

2016-05-01

Human bite marks are often sustained during sexual, domestic or child abuse. Currently, analysis of these marks involves digital photography techniques along with an expert forensic odontologist opinion. Photographs often focus closely on the bite mark and give little context to the anatomical location of the injury. Due to variation in camera models and expertise of the photographer, photograph quality can affect its interpretation. Additionally, it can sometimes be days between injury and examination, allowing the injury pattern and colour to alter, making it harder to analyse. To investigate if a 3D imaging technique, creating a time-lapse image of a bite mark in three dimensions, can provide context to the injury in terms of nature and location, and also allow analysis of the change in appearance of a bite mark over time. Participants had an experimental bite mark produced on their forearm by dental casts mounted on a dental articulator. The forearms were photographed immediately following the bite, and at intervals of 3, 6, 24, 48, 72 and 96 h. A DI3D(®) (Dimensional Imaging 3D) photogrammetry system and Autodesk Maya 2015(®) software was used to create a 3D animation from the images obtained. The clearest, long lasting bite mark injuries were selected for animation, enabling the 3D imaging technique to be used optimally. 3D time-lapse animations were successfully created with the ability to be viewed on most electronic devices. With further refinement this technique could be valuable in a number of areas. We anticipate animations produced in this way to have significant benefit to the presentation of photographic evidence in a court setting, and in age estimation of injuries. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Predicting the risk of Lyme borreliosis after a tick bite, using a structural equation model

PubMed Central

Sprong, Hein; van den Wijngaard, Cees C.; Harms, Margriet G.; Fonville, Manoj; Docters van Leeuwen, Arieke; Simões, Mariana; van Pelt, Wilfrid

2017-01-01

Background Understanding and quantification of the risk of Lyme borreliosis after a tick bite can aid development of prevention strategies against Lyme borreliosis. Methods We used 3,525 single tick bite reports from three large prospective studies on the transmission risk of tick-borne pathogens to humans, with 50 reports of Lyme borreliosis during the follow-up period, among 1,973 reports with known outcome. A structural equation model was applied to estimate the risk of Lyme borreliosis after a tick bite, and quantify the influence of: developmental stage of the tick, detection of Borrelia burgdorferi s.l. DNA in the tick by PCR, tick engorgement, patient-estimated duration of tick attachment, and patient age. Results The overall risk of developing Lyme borreliosis after a tick bite was 2.6% (95%CI 1.4–5.1). The risk increased with: - Tick engorgement: 1.4% (95%CI 0.7%-2.3%) for low engorgement to 5.5% (95%CI 2.8%-9.2%) for substantially engorged ticks; - Rising patient-estimated tick attachment duration: 2.0% (95%CI 1.3%-2.8%) after <12 hours, to 5.2% (95%CI 3.0%-8.9%) after ≥4 days; - Detection of Borrelia burgdorferi s.l. DNA in ticks: 6.7% (95%CI 3.6%-13.5%), versus 1.4% (95%CI 0.7%-2.9%) when ticks tested negative. The highest observed risk of Lyme borreliosis was 14.4% (95%CI 6.8%-24.6%) after one tick bite of a substantially engorged tick that tested positive for Borrelia burgdorferi s.l. DNA, which corresponds to one new case of Lyme borreliosis per 7 (95%CI 4–15) of such tick bites. Conclusions An individual's risk of Lyme borreliosis after a tick bite can be predicted with tick engorgement, patient-estimated duration of tick attachment, and detection of Borrelia burgdorferi s.l. DNA in the tick. PMID:28742149

Human onchocerciasis in the Amazonian area of southern Venezuela: spatial and temporal variations in biting and parity rates of black fly (Diptera: Simuliidae) vectors.

PubMed

Grillet, M E; Basáñez, M G; Vivas-Martínez, S; Villamizar, N; Frontado, H; Cortez, J; Coronel, P; Botto, C

2001-07-01

We investigated some entomological factors underlying altitudinal prevalence variation in the Venezuelan Amazonia human onchocerciasis focus. Spatial and temporal variation in relative abundance, daily biting rate, proportion of parous flies, and monthly parous biting rate were studied for the three main simuliid vectors (based on their vectorial competence: Simulium oyapockense s.l. Floch & Abonnenc approximately = S. incrustatum Lutz < S. guianense s.l. Wise). Yanomami villages were selected among sentinel communities of the ivermectin control program, representing hypo- to hyperendemicity conditions of infection. Spatial variation was explored via increasing village altitude on two river systems (A: Ocamo-Putaco and B: Orinoco-Orinoquito). Temporal variation was studied between 1995 and 1999 by sampling the biting population during dry and rainy mouths. Environmental variables included monthly rainfall and maximum river height. Simuliid species composition itself varied along the altitudinal and prevalence gradient. S. oyapockense s.l. prevailed below 150 m. Above this altitude and up to 240 m, S. incrustatum and S. guianense s.l. became more frequently and evenly collected along A but not along B, where S. incrustatum remained absent. The daily biting rate of S. oyapockense s.l. was higher during the dry season along A, whereas the converse took place along B. Daily biting rate of S. incrustatum was lowest during early rains. By contrast, the daily biting rate of S. guianense s.l. was highest during this period. There was a significant negative cross-correlation between proportion of parous of S. oyapockense s.l. and river height (2 and 3 mo lagged), whereas this variable (1 and 2 mo lagged) was positively correlated with the proportion of parous flies for S. incrustatum. Monthly parous biting rate values suggest that the months contributing most to onchocerciasis transmission in the area are likely to be the dry season and the transition periods between seasons.

Predicting the risk of Lyme borreliosis after a tick bite, using a structural equation model.

PubMed

Hofhuis, Agnetha; van de Kassteele, Jan; Sprong, Hein; van den Wijngaard, Cees C; Harms, Margriet G; Fonville, Manoj; Docters van Leeuwen, Arieke; Simões, Mariana; van Pelt, Wilfrid

2017-01-01

Understanding and quantification of the risk of Lyme borreliosis after a tick bite can aid development of prevention strategies against Lyme borreliosis. We used 3,525 single tick bite reports from three large prospective studies on the transmission risk of tick-borne pathogens to humans, with 50 reports of Lyme borreliosis during the follow-up period, among 1,973 reports with known outcome. A structural equation model was applied to estimate the risk of Lyme borreliosis after a tick bite, and quantify the influence of: developmental stage of the tick, detection of Borrelia burgdorferi s.l. DNA in the tick by PCR, tick engorgement, patient-estimated duration of tick attachment, and patient age. The overall risk of developing Lyme borreliosis after a tick bite was 2.6% (95%CI 1.4-5.1). The risk increased with: - Tick engorgement: 1.4% (95%CI 0.7%-2.3%) for low engorgement to 5.5% (95%CI 2.8%-9.2%) for substantially engorged ticks;- Rising patient-estimated tick attachment duration: 2.0% (95%CI 1.3%-2.8%) after <12 hours, to 5.2% (95%CI 3.0%-8.9%) after ≥4 days;- Detection of Borrelia burgdorferi s.l. DNA in ticks: 6.7% (95%CI 3.6%-13.5%), versus 1.4% (95%CI 0.7%-2.9%) when ticks tested negative.The highest observed risk of Lyme borreliosis was 14.4% (95%CI 6.8%-24.6%) after one tick bite of a substantially engorged tick that tested positive for Borrelia burgdorferi s.l. DNA, which corresponds to one new case of Lyme borreliosis per 7 (95%CI 4-15) of such tick bites. An individual's risk of Lyme borreliosis after a tick bite can be predicted with tick engorgement, patient-estimated duration of tick attachment, and detection of Borrelia burgdorferi s.l. DNA in the tick.

[The primary closure approach of dog bite injuries of the nose].

PubMed

Zieliński, Tomasz

2010-01-01

Biting of humans by domestic animals, especially by dogs, is common injury which causes suffering and pain, might be a cause of disability or even death. It is associated with high risk of bacterial infection of the wounds or even transfection of rabies virus. Bites are usually to the upper and lower limbs, while the face is third in a raw localization of bites. Within the face, the nose and lips are injured the most often. The goal of this paper is presentation selected methods and obtained results of primary closure of dog bite injures of the nose. There were 16 patients with dog bites injures of the nose treated in the Department of Plastic, Reconstructive and Aesthetic Surgery of the Medical University of Łódź in the years 2003-2008. The patients were 11 to 46 years old. Bites caused either superficial laceration of the skin, tearing of the nostril wing or even major defects of the tissues. In 7 patients superficial wounds a direct closure was done and antibiotic ointment was applied. In 7 patients a defect of the skin was covered with a skin graft taken from retroauricular area, but in 2 of the patients of this group repair of mucosa and alar cartilage was done. In two persons with full thickness defects of the nose reconstruction was performed with the use of a pedicled nosolabial flap. Complications occurred only in 1 patient who developed infection in the wound. In all other patients there were no complications. Good aesthetic results were obtained. Primary closure approach of bite injures with tissue defect is not associated with larger risk than in the case in secondary such approach, and should be implemented always whenever it is possible in order to avoid risk of wound and scars which require further reconstructive procedures in future.

Tongue Blade Bite Test Predicts Mandible Fractures

PubMed Central

Neiner, John; Free, Rachael; Caldito, Gloria; Moore-Medlin, Tara; Nathan, Cherie-Ann

2015-01-01

The aim of the study is to evaluate the utility of a simple tongue blade bite test in predicting mandible fractures and use this test as an alternative screening tool for further workup. This is a retrospective chart review. An institutional review board approved the retrospective review of patients evaluated by the Department of Otolaryngology at a single institution for facial trauma performed from November 1, 2011, to February 27, 2014. Patients who had a bite test documented were included in the study. CT was performed in all cases and was used as the gold standard to diagnose mandible fractures. Variables analyzed included age, sex, fracture type/location on CT, bite test positivity, and operative intervention. A total of 86 patients met the inclusion criteria and of those 12 were pediatric patients. Majority of the patients were male (80.2%) and adult (86.0%; average age: 34.3 years). Fifty-seven patients had a negative bite test and on CT scans had no mandible fracture. Twenty-three patients had a positive bite test and a CT scan confirmed fracture. The bite test revealed a sensitivity of 88.5% (95% CI: 69.8–97.6%), specificity of 95.0% (95% CI:86.1–99%), positive predictive value [PPV] of 88.5% (95% CI: 69.8–97.6%), and negative predictive value [NPV] of 95.0% (95% CI: 86.1–99.0%). Among pediatric patients, the sensitivity was 100% (95% CI: 29.9–100%), specificity was 88.9% (95% CI: 68.4–100%), PPV was 75.0% (95% CI: 19.4–99.4%), and NPV was 100% (95% CI: 63.1–100%). The tongue blade bite test is a quick inexpensive diagnostic tool for the otolaryngologist with high sensitivity and specificity for predicting mandible fractures. In the pediatric population, where avoidance of unnecessary CT scans is of highest priority, a wider range of data collection should be undertaken to better assess its utility. PMID:27162567

Variations in household microclimate affect outdoor-biting behaviour of malaria vectors

PubMed Central

Ngowo, Halfan S.; Kaindoa, Emmanuel Wilson; Matthiopoulos, Jason; Ferguson, Heather M.; Okumu, Fredros O.

2017-01-01

Background: Mosquito behaviours including the degree to which they bite inside houses or outside is a crucial determinant of human exposure to malaria. Whilst seasonality in mosquito vector abundance is well documented, much less is known about the impact of climate on mosquito behaviour. We investigated how variations in household microclimate affect outdoor-biting by malaria vectors, Anopheles arabiensis and Anopheles funestus. Methods: Mosquitoes were sampled indoors and outdoors weekly using human landing catches at eight households in four villages in south-eastern Tanzania, resulting in 616 trap-nights over 12 months. Daily temperature, relative humidity and rainfall were recorded. Generalized additive mixed models (GAMMs) were used to test associations between mosquito abundance and the microclimatic conditions. Generalized linear mixed models (GLMMs) were used to investigate the influence of microclimatic conditions on the tendency of vectors to bite outdoors (proportion of outdoor biting). Results:  An. arabiensis abundance peaked during high rainfall months (February-May), whilst An. funestus density remained stable into the dry season (May-August) . Across the range of observed household temperatures, a rise of 1 ºC marginally increased nightly An. arabiensis abundance (~11%), but more prominently increased An. funestus abundance (~66%). The abundance of An. arabiensis and An. funestus showed strong positive associations with time-lagged rainfall (2-3 and 3-4 weeks before sampling). The degree of outdoor biting in An. arabiensis was significantly associated with the relative temperature difference between indoor and outdoor environments, with exophily increasing as temperature inside houses became relatively warmer. The exophily of An. funestus did not vary with temperature differences.   Conclusions: This study demonstrates that malaria vector An. arabiensis shifts the location of its biting from indoors to outdoors in association with relative differences in microclimatic conditions. These environmental impacts could give rise to seasonal variation in mosquito biting behaviour and degree of protection provided by indoor-based vector control strategies. PMID:29552642

Retrospective analysis of snake victims in Northern India admitted in a tertiary level institute

PubMed Central

Ahmed, Syed Moied; Nadeem, Abu; Islam, Mohd. Sabihul; Agarwal, Shiwani; Singh, Lalit

2012-01-01

Context: Snake bites are the common cause of morbidity and mortality in tropical countries. Aims: To analyze the outcome of snake bite victims Settings and Design: Retrospective analysis of data from Intensive care unit, Department of Anesthesiology. Materials and Methods: All the patients admitted in the intensive care unit for snake bite management during the year May 2004 - April 2009 were retrospectively reviewed. The data included age, sex, month and time of incident, site of bite, dose of anti--snake venom, time of anti--snake venom, administration, duration of mechanical ventilation, complications and death of a victim. Statistical analysis used: Pearson's correlation test, paired samples t-test. Results and Conclusions: 113 patients reported to the Accident and Emergency with history of snake bite. 26 patients were referred to other hospital, 17 patients were brought dead, and 70 patients were admitted to the intensive care unit. In 59 snake-bite victims, maximum data could be recovered. Krait was the most common type of snake bite reported. There was a male preponderance (69.4%) with age ranging between 20 and 40 years (52.5%). The mean lag time (time elapsed between bite and first dose of anti--snake venom) was 5.3 ± 1.4 h and the mean anti-snake venom dose was 12.3 ± 2.4 vials. There was a positive and significant correlation between lag time and total dose of anti--snake venom (correlation coefficient =0.956, P<0.0001). Overall 72.9% patients required mechanical ventilation with a mean duration of 56.2 ± 16.1 h. 10.2% patients sustained cardiac arrest, 8.7% patients developed ventilator associated pneumonia, 6.7% suffered mild anti-snake venom reaction, 6.7% had hypotension and 5.1% patients developed renal failure. The overall mortality was 5.1%. PMID:22345945

Knowledge, attitudes and practices regarding rabies risk in community members and healthcare professionals: Pétionville, Haiti, 2013.

PubMed

Fenelon, N; Dely, P; Katz, M A; Schaad, N D; Dismer, A; Moran, D; Laraque, F; Wallace, R M

2017-06-01

Haiti has the highest human rabies burden in the Western Hemisphere. There is no published literature describing the public's perceptions of rabies in Haiti, information that is critical to developing effective interventions and government policies. We conducted a knowledge, attitudes and practices survey of 550 community members and 116 health professionals in Pétionville, Haiti in 2013 to understand the perception of rabies in these populations. The majority of respondents (85%) knew that dogs were the primary reservoir for rabies, yet only 1% were aware that bats and mongooses could transmit rabies. Animal bites were recognized as a mechanism of rabies transmission by 77% of the population and 76% were aware that the disease could be prevented by vaccination. Of 172 persons reporting a bite, only 37% sought medical treatment. The annual bite incidence rate in respondents was 0·9%. Only 31% of bite victims reported that they started the rabies vaccination series. Only 38% of respondents reported that their dog had been vaccinated against rabies. The majority of medical professionals recognized that dogs were the main reservoir for rabies (98%), but only 28% reported bats and 14% reported mongooses as posing a risk for rabies infection. Bites were reported as a mechanism of rabies transmission by 73% of respondents; exposure to saliva was reported by 20%. Thirty-four percent of medical professionals reported they would wash a bite wound with soap and water and 2·8% specifically mentioned rabies vaccination as a component of post-bite treatment. The majority of healthcare professionals recommended some form of rabies assessment for biting animals; 68·9% recommended a 14-day observation period, 60·4% recommended a veterinary consultation, and 13·2% recommended checking the vaccination status of the animal. Fewer than 15% of healthcare professionals had ever received training on rabies prevention and 77% did not know where to go to procure rabies vaccine for bite victims. Both study populations had a high level of knowledge about the primary reservoir for rabies and the mode of transmission. However, there is a need to improve the level of knowledge regarding the importance of seeking medical care for dog bites and additional training on rabies prevention for healthcare professionals. Distribution channels for rabies vaccines should be evaluated, as the majority of healthcare providers did not know where rabies vaccines could be obtained. Canine rabies vaccination is the primary intervention for rabies control programmes, yet most owned dogs in this population were not vaccinated.

Fixed versus Removable Appliance for Palatal Expansion; A 3D Analysis Using the Finite Element Method

PubMed Central

Geramy, Allahyar; Shahroudi, Atefe Saffar

2014-01-01

Objective: Several appliances have been used for palatal expansion for treatment of posterior cross bite. The purpose of this study was to evaluate the stress induced in the apical and crestal alveolar bone and the pattern of tooth displacement following expansion via removable expansion plates or fixed-banded palatal expander using the finite element method (FEM) analysis. Materials and Methods: Two 3D FEM models were designed from a mesio-distal slice of the maxilla containing the upper first molars, their periodontium and alveolar bone. Two palatal expanders (removable and fixed) were modeled. The models were designed in SolidWorks 2006 and then transferred to ANSYS Workbench. The appliance halves were displaced 0.1 mm laterally. The von Mises stress in the apical, crestal, and PDL areas and also the vertical displacement of the cusps (palatal and buccal) was were evaluated. Results: The total PDL stress was 0.40003 MPa in the removable appliance (RA) model and 4.88e-2 MPa in the fixed appliance (FA) model and the apical stress was 9.9e-2 and 1.17e-2 MPa, respectively. The crestal stress was 2.99e-1 MPa in RA and 7.62e-2 MPa in the FA. The stress in the cortical bone crest was 0.30327 and 7.9244e-2 MPa for RA and FA, respectively and 3.7271 and 7.4373e-2 MPa in crestal area of spongy bone, respectively. The vertical displacement of the buccal cusp and palatal cusp was 1.64e-2 and 5.90e-2 mm in RA and 1.05e-4 and 1.7e-4 mm in FA, respectively. Conclusion: The overall stress as well as apical and crestal stress in periodontium of anchor teeth was higher in RA than FA; RA elicited higher stress in both cortical and spongy bone. The vertical displacement of molar cusps was more in removable than fixed palatal expander model. PMID:24910679

The paleobiology of Amphipithecidae, South Asian late Eocene primates.

PubMed

Kay, Richard F; Schmitt, Daniel; Vinyard, Christopher J; Perry, Jonathan M G; Shigehara, Nobuo; Takai, Masanaru; Egi, Naoko

2004-01-01

Analysis of the teeth, orbital, and gnathic regions of the skull, and fragmentary postcranial bones provides evidence for reconstructing a behavioral profile of Amphipithecidae: Pondaungia, Amphipithecus, Myanmarpithecus (late middle Eocene, Myanmar) and Siamopithecus (late Eocene, Thailand). At 5-8 kg, Pondaungia, Amphipithecus, and Siamopithecus are perhaps the largest known Eocene primates. The dental and mandibular anatomy suggest that large-bodied amphipithecids were hard-object feeders. The shape of the mandibular corpus and stiffened symphysis suggest an ability to resist large internal loads during chewing and to recruit significant amounts of muscle forces from both the chewing and non-chewing sides of the jaw so as to increase bite force during mastication. The large spatulate upper central incisor of Pondaungia and projecting robust canines of all the larger amphipithecids suggest that incisal food preparation was important. The molars of Siamopithecus, Amphipithecus, and Pondaungia have weak shearing crests. This, and the thick molar enamel found in Pondaungia, suggests a diet of seeds and other hard objects low in fiber. In contrast, Myanmarpithecus was smaller, about 1-2 kg; its cheek teeth suggest a frugivorous diet and do not imply seed eating. Postcranial bones (humerus, ulna, and calcaneus) of a single large amphipithecid individual from Myanmar suggest an arboreal quadrupedal locomotor style like that of howler monkeys or lorises. The humeral head is rounded, proximally oriented, and the tuberosities are low indicating an extremely mobile glenohumeral joint. The great thickness of the midshaft cortical bone of the humerus implies enhanced ability to resist bending and torsion, as seen among slow moving primate quadrupeds. The elbow joint exhibits articular features for enhanced stability in habitually flexed positions, features also commonly found in slow moving arboreal quadrupeds. The short distal load arm of the calcaneus is consistent with, but not exclusive to, slow, arboreal quadrupedalism, and suggests no reliance on habitual leaping.

C1-C2 alkyl aminiums in urban aerosols: Insights from ambient and fuel combustion emission measurements in the Yangtze River Delta region of China.

PubMed

Shen, Wenchao; Ren, Lili; Zhao, Yi; Zhou, Luyu; Dai, Liang; Ge, Xinlei; Kong, Shaofei; Yan, Qin; Xu, Honghui; Jiang, Yujun; He, Jun; Chen, Mindong; Yu, Huan

2017-11-01

We measured low molar-mass alkyl aminiums (methylaminium, dimethylaminium, ethylaminium and diethylaminium) in urban aerosols in the Yangtze River Delta region of eastern China in August 2014 and from November 2015 to May 2016. After examining artifact formation on sample filters, methylaminium, dimethylaminium and ethylaminium concentrations were quantified. The three C1-C2 aminiums exhibited a unimodal size distribution that maximized between 0.56 and 1.0 μm. Their concentrations in PM 2.5 were 5.7 ± 3.2 ng m -3 , 7.9 ± 5.4 ng m -3 and 20.3 ± 16.6 ng m -3 , respectively, with higher concentrations during the daytime and in warm seasons. On new particle growth days, amine uptake to particles larger than 56 nm was barely enhanced. The molar ratios of individual aminium/NH 4 + in PM 2.5 were on the order of 10 -4 and 10 -3 . Aminiums were thus far less to out-compete ammonium (NH 4 + ) in neutralizing acidic species in particle sizes down to 56 nm. Abundant nitrate (NO 3 - /SO 4 2- molar ratio = ∼3) and its correlation to methylaminium and ethylaminium implied that nitrate might be more important aminium salt than sulfate in urban aerosols of this area. Direct measurement of particle-phase amine emission from coal and biomass burning showed that coal burning is an important atmospheric amine source, considering coal burning is top-ranked particulate matter source in China. Copyright © 2017 Elsevier Ltd. All rights reserved.

Emergence of antirabies vaccine of unknown origin for human treatment in Nigeria.

PubMed

Ogunkoya, A B; Macconi, F

1986-06-01

Rabies is endemic in Nigeria. It is one of the most important and dreadful zoonotic diseases in the country and the dog is seen as the principal host and reservoir animal. Fatal human rabies resulting from dog bites has been reported. Dog bites in Nigeria occur regularly throughout the year and the rate of bite could be considered very high. The treatment of the exposed has been a matter of concern.

Acute kidney injury following rhabdomyolysis and sepsis after non-poisonous desert monitor bite.

PubMed

Gupta, Poonam; Verma, Pradeep Kumar

2017-10-01

The desert monitor, Varanus griseus , is a species of desert monitor lizard found in North-Western India. They are believed to be non-poisonous. We report a case of Indian desert monitor bite leading to acute renal failure following rhabdomyolysis and severe sepsis. Prompt diagnosis and treatment resulted in the favourable outcome. This is author's intent to highlight the complication that may occur after Indian desert monitor bite.

Streptobacillus moniliformis Bacteremia in a Pet Shop Employee: Case Report and Literature Review.

PubMed

Suzuki, Kiyozumi; Hirai, Yuji; Morita, Fujiko; Nakamura, Ayako; Uehara, Yuki; Naito, Toshio

2017-01-01

A 39-year-old pet shop employee who sustained a bite from one of his store's rats developed fever and arthritis. Streptobacillus moniliformis was cultured from the patient's blood, confirming a diagnosis of rat-bite fever. Treatment with standard antibiotics was successful. Although rat-bite fever is commonly considered a zoonosis transmitted by wild or laboratory rats, our case emphasizes that it may be transmitted by pet animals as well.

Bite angle effects of diphosphines in C-C and C-X bond forming cross coupling reactions.

PubMed

Birkholz, Mandy-Nicole; Freixa, Zoraida; van Leeuwen, Piet W N M

2009-04-01

Catalytic reactions of C-C and C-X bond formation are discussed in this critical review with particular emphasis on cross coupling reactions catalyzed by palladium and wide bite angle bidentate diphosphine ligands. Especially those studies have been collected that allow comparison of the ligand bite angles for the selected ligands: dppp, BINAP, dppf, DPEphos and Xantphos. Similarities with hydrocyanation and CO/ethene/MeOH reactions have been highlighted, while rhodium hydroformylation has been mentioned as a contrasting example, in which predictability is high and steric and electronic effects follow smooth trends. In palladium catalysis wide bite angles and bulkiness of the ligands facilitate generally the reductive elimination thus giving more efficient cross coupling catalysis (174 references).

[Hypersensitivity to mosquito bite manifested as Skeeter síndrome].

PubMed

Pérez-Vanzzini, Rafael; González-Díaz, Sandra Nora; Arias-Cruz, Alfredo; Palma-Gómez, Samuel; Yong-Rodríguez, Adrián; Gutiérrez-Mujica, José Julio; García-Calderín, Diego; Ibarra, Jesús Arturo

2015-01-01

The reactions to mosquito bites are immunological reactions with involvement of IgE, IgG and T cells mediated hypersensitivity. These reactions are common and range from small local reactions, large local reactions to systemic allergic reactions. Skeeter syndrome is defined as a large local induced inflammatory reaction to mosquito bite and sometimes accompanied by systemic symptoms such as fever and vomiting. Diagnosis is based on clinical history and physical examination, supported by the identification of specific IgE by skin testing. Treatment includes prevention, antihistamines and steroids in some cases. Specific immunotherapy still requires further study. This paper reports two cases of patients with hypersensitivity reactions to mosquito bites, which were evaluated in our center presenting positive skin tests.

Factors associated with tick bites and pathogen prevalence in ticks parasitizing humans in Georgia, USA.

PubMed

Gleim, Elizabeth R; Garrison, Laurel E; Vello, Marianne S; Savage, Mason Y; Lopez, Gaylord; Berghaus, Roy D; Yabsley, Michael J

2016-03-02

The incidence and emergence of tick-borne diseases has increased dramatically in the United States during the past 30 years, yet few large-scale epidemiological studies have been performed on individuals bitten by ticks. Epidemiological information, including disease development, may provide valuable information regarding effectiveness of tick bite prevention education, pathogen transmission, human-disease dynamics, and potential implications for under reporting of tick-borne diseases. Ticks found attached to Georgia residents were submitted for identification and polymerase chain reaction (PCR) testing for Francisella tularensis, Ehrlichia, Anaplasma, Borrelia, and Rickettsia spp. Tick bite victims were interviewed three weeks after the tick bite to identify various epidemiologic factors associated with infestation and if signs suggestive of a tick-borne disease had developed. Fisher's exact test of independence was used to evaluate associations between various factors evaluated in the study. A multivariable logistic regression model was used for the prediction of non-specific illness post-tick bite. From April 2005-December 2006, 444 participants submitted 597 ticks (426 Amblyomma americanum, 142 Dermacentor variabilis, 19 A. maculatum, 7 Ixodes scapularis, 3 Amblyomma sp.) which originated from 95 counties. Only 25 (34 %) of 74 interviewed individuals purposely took tick bite prevention measures. Ticks that were PCR positive for bacterial organisms were attached to 136 participants. Of the 77 participants who developed non-specific illness, 50 did not have PCR positive ticks, whereas 27 did have PCR positive tick (s). Of those 27 individuals, 12 fit the criteria for a possible tick-borne illness (i.e., tick attached >6 h [if known], ≥4 day incubation period, and the individual exhibited clinical symptoms typical of a tick-borne illness without exhibiting cough, sore throat, or sinus congestion). Ticks from these individuals were positive for R. amblyommii (n = 8), E. ewingii (n = 1), R. montana (n = 1), R. rhiphicephali (n = 1), and Rickettsia sp. TR-39 (n = 1). Although illnesses reported in this study cannot definitively be connected with tick bites, it does provide insight into development, diagnosis, and treatment of possible tick-borne diseases post-tick bite. The study also provided data on pathogen prevalence, and epidemiologic factors associated with tick bites, as well as tick presence by county in Georgia.

Light manipulation of mosquito behaviour: acute and sustained photic suppression of biting activity in the Anopheles gambiae malaria mosquito.

PubMed

Sheppard, Aaron D; Rund, Samuel S C; George, Gary F; Clark, Erin; Acri, Dominic J; Duffield, Giles E

2017-06-16

Host-seeking behaviours in anopheline mosquitoes are time-of-day specific, with a greater propensity for nocturnal biting. We investigated how a short exposure to light presented during the night or late day can inhibit biting activity and modulate flight activity behaviour. Anopheles gambiae (s.s.), maintained on a 12:12 LD cycle, were exposed transiently to white light for 10-min at the onset of night and the proportion taking a blood meal in a human biting assay was recorded every 2 h over an 8-h duration. The pulse significantly reduced biting propensity in mosquitoes 2 h following administration, in some trials for 4 h, and with no differences detected after 6 h. Conversely, biting levels were significantly elevated when mosquitoes were exposed to a dark treatment during the late day, suggesting that light suppresses biting behaviour even during the late daytime. These data reveal a potent effect of a discrete light pulse on biting behaviour that is both immediate and sustained. We expanded this approach to develop a method to reduce biting propensity throughout the night by exposing mosquitoes to a series of 6- or 10-min pulses presented every 2 h. We reveal both an immediate suppressive effect of light during the exposure period and 2 h after the pulse. This response was found to be effective during most times of the night: however, differential responses that were time-of-day specific suggest an underlying circadian property of the mosquito physiology that results in an altered treatment efficacy. Finally, we examined the immediate and sustained effects of light on mosquito flight activity behaviour following exposure to a 30-min pulse, and observed activity suppression during early night, and elevated activity during the late night. As mosquitoes and malaria parasites are becoming increasingly resistant to insecticide and drug treatment respectively, there is a necessity for the development of innovative control strategies beyond insecticide-treated nets (ITNs) and residual spraying. These data reveal the potent inhibitory effects of light exposure and the utility of multiple photic pulses presented at intervals during the night/late daytime, may prove to be an effective tool that complements established control methods.

[Investigation into the actual condition of patients with occlusal disharmony at the Pedodontic Clinic of Kyushu University. Cases of anterior cross-bite in the deciduous dentition].

PubMed

Yamasaki, K; Hirota, K; Yamasaki, Y; Nonaka, K; Nakata, M

1989-01-01

The total number of subjects was 2754 children (1354 boys and 1402 girls), who visited the Pedodontic Clinic of Kyushu University during the 5 year period from April 1st 1981 to March 31st 1986. We investigated the actual conditions of patients who complained of occlusal disharmony and who were ascertained to be associated with occlusal disharmony. The results were as follows: 1. The percentage ratio of patients with chief complaints concerning occlusions was 14.5% and the percentage of patients with various type of complaints as well as the problem of occlusion was 8.1%. The ratio of the sex of the patients who complained of their occlusal disharmony was 43.0% for boys and 57.0% for girls. 2. The age distributions of the patients who had as the chief complaint occlusal disharmony were at the ages of 3 and 6 to 7 at the maximum. 3. The number of patients who were diagnosed with occlusal disharmony at the first examination was 28.5%. These included anterior cross-bite 32.5%, edge to edge bite 14.1%, cross-bite 13.0%, crowding 11.8% and et al. 4. The distribution of anterior cross-bites due to the developmental stage was divided into the deciduous dentition 59.9%, the mixed dentition 39.3% and the permanent dentition 0.8%. 5. The sex ratios of anterior cross-bites in the deciduous dentition were 45.6% for boys and 54.4% for girls. 6. The treatment of occlusal guidance for anterior cross-bite in the deciduous dentition started from ages 3 to 5. 7. The appliances used for the treatment of anterior cross-bite in the deciduous dentition were maxillary protraction 25.0%, the chin cap 20.0%, the FKO 17.5%, and the lingual arch with herical springs 15.0% and et al. 8. The status of the patients with the anterior cross-bite in the deciduous dentition as of August 1986 was that the 36.2% was under the observation, and 24.4% was under the treatment of occlusal guidance or under the observation after the treatment was done.

Projected economic losses due to vector and vector-borne parasitic diseases in livestock of India and its significance in implementing the concept of integrated practices for vector management

PubMed Central

Narladkar, B. W.

2018-01-01

Broadly, species of arthropods infesting livestock are grouped into flies (biting and non-biting), fleas, lice (biting and sucking), ticks (soft and hard), and mites (burrowing, non-burrowing, and follicular). Among which, biting and non-biting flies and ticks are the potent vectors for many bacterial, viral, rickettsial, and protozoan diseases. Vectors of livestock are having economic significance on three points (1) direct losses from their bite and annoyance, worries, and psychological disturbances produced during the act of biting and feeding, (2) diseases they transmit, and (3) expenditure incurred for their control. Flies such as Culicoides spp. and Musca spp. and various species of hard ticks play important role in disease transmission in addition to their direct effects. For control of vectors, recent concept of integrated pest management (IPM) provides the best solution and also addresses the problems related to acaricide resistance and environmental protection from hazardous chemicals. However, to successfully implement the concept of IPM, for each vector species, estimation of two monitory benchmarks, i.e., economic injury level (EIL) and economic threshold level (ETL) is essential prerequisite. For many vector species and under several circumstances, estimation of EIL and ETL appears to be difficult. Under such scenario, although may not be exact, an approximate estimate can be accrued by taking into account several criteria such as percent prevalence of vectors in a geographical area, percent losses produced, total livestock population, and current prices of livestock products such as milk, meat, and wool. Method for approximate estimation is first time described and elaborated in the present review article. PMID:29657396

Factors affecting outcome in children with snake envenomation: a prospective observational study.

PubMed

Sankar, Jhuma; Nabeel, Rehana; Sankar, M Jeeva; Priyambada, Leena; Mahadevan, S

2013-08-01

To evaluate clinical outcome and factors affecting outcome in children with snake envenomation. Prospective observational study. Paediatric intensive care unit of a tertiary care teaching hospital in India. We prospectively enrolled children ≤12 years of age admitted to our hospital with a definitive history of snake bite from August 2007 to June 2010. Demographic characteristics and clinical course of the enrolled children were recorded in a structured proforma and analysed using appropriate statistical methods. Children were treated as per the WHO guidelines (2005) on the management of snake bite in children. Of 110 children studied, 77 (69%) were male. Most (72; 64.2%) had features predominantly of haematotoxic envenomation while 20 (18%) and 18 (16%) children had features of neurotoxic envenomation and local involvement, respectively. 14 children (13%) died and 13 (12%) had major disabilities. On univariable analysis, the following prehospital and admission variables were found to be significantly associated with poor outcome: age, walking for >1 km after the bite, vomiting, haemoglobin ≤10 g/dl at admission and species of snake (cobra). On multivariable analysis, only younger age (adjusted OR 0.85; 95% CI 0.7 to 0.9), walking for >1 km after the bite (adjusted OR 57; 95% CI 4.2 to 782) and haemoglobin ≤10 g/dl at admission (adjusted OR 6; 95% CI 2 to 18.2) remained significant. Younger age at presentation, anaemia (haemoglobin ≤10 g/dl) and distance walked after the bite may be independent predictors of mortality and morbidity in children with snake bite. These features in victims of snake bite warrant early referral to and management in tertiary care centres.

Ethnomedicinal uses of plants for the treatment of snake and scorpion bite in Northern Pakistan.

PubMed

Butt, Maryam Akram; Ahmad, Mushtaq; Fatima, Anam; Sultana, Shazia; Zafar, Muhammad; Yaseen, Ghulam; Ashraf, Muhammad Aqeel; Shinwari, Zabta Khan; Kayani, Sadaf

2015-06-20

Medicinal plants represent one of the most accessible resources available for snake and scorpion bite among the rural communities of Northern Pakistan. This first ethno-botanical study aimed to document the indigenous knowledge and practices of using plants for snake and scorpion bite disorders in Northern Pakistan. Ethno-medicinal data is documented from 187 informants using semi-structured interviews. The data is analyzed using quantitative ethno-botanical indices of frequency citation (FC) and relative Frequency of Citation (RFC). In addition to this, the ethno-medicinal findings of this survey were compared with 10 previous published studies in order to report novel uses of medicinal plants against snake and scorpion bite disorders. In total 62 medicinal plants belonging to 40 families are reported against snake and scorpion bite in this study. Our results showed that Asteraceae is the most used family (10 species), dominant life form is herb (48.38%), leaves were the most used plants part (18 Use-reports) and the paste is most used method of administration (22 reports). The range of RFC was 0.08-0.27 about the use of documented species. Compared to previous published studies, 33.87% similarity index while 66.12% novelty index is reported. About 40 plant species are first time reported with medicinal uses against snake and scorpion bite from Northern Pakistan. This study presents useful traditional knowledge of rural communities for the control of snake and scorpion bite using medicinal plants. The study mainly focused on ethno-medicinal documentation to preserve the valuable traditional knowledge that can be used in future phytochemical and pharmacological studies on medicinal plants of the area. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A systematic review of risk of HIV transmission through biting or spitting: implications for policy.

PubMed

Cresswell, F V; Ellis, J; Hartley, J; Sabin, C A; Orkin, C; Churchill, D R

2018-04-23

The perceived threat of HIV transmission through spitting and biting is evidenced by the increasing use of "spit hoods" by Police Forces in the UK. In addition, a draft parliamentary bill has called for increased penalties for assaults on emergency workers, citing the risk of communicable disease transmission as one justification. We aimed to review literature relating to the risk of HIV transmission through biting or spitting. A systematic literature search was conducted using Medline, Embase and Northern Lights databases and conference websites using search terms relating to HIV, AIDS, bite, spit and saliva. Inclusion and exclusion criteria were applied to identified citations. We classified plausibility of HIV transmission as low, medium, high or confirmed based on pre-specified criteria. A total of 742 abstracts were reviewed, yielding 32 articles for full-text review and 13 case reports/series after inclusion and exclusion criteria had been applied. There were no reported cases of HIV transmission related to spitting and nine cases identified following a bite, in which the majority occurred between family (six of nine), in fights involving serious wounds (three of nine), or to untrained first-aiders placing fingers in the mouth of someone having a seizure (two of nine). Only four cases were classified as highly plausible or confirmed transmission. None related to emergency workers and none were in the UK. There is no risk of transmitting HIV through spitting, and the risk through biting is negligible. Post-exposure prophylaxis is not indicated after a bite in all but exceptional circumstances. Policies to protect emergency workers should be developed with this evidence in mind. © 2018 The Authors. HIV Medicine published by John Wiley & Sons Ltd on behalf of British HIV Association.

Injuries due to human and animal aggression in humans.

PubMed

Łabęcka, Marzena; Lorkiewicz-Muszyńska, Dorota E; Przystańska, Agnieszka; Kondrusiewicz, Krzysztof

2013-01-01

People breed animals, professionally take care of them, and work with them. To live with animals, however, it is necessary to know their behaviour and habits, as well as fears. Ignorance of this knowledge may lead to tragedy for the victim (a person), as well as for the beast (animal). Then, nobody cares whether the animal behaved itself or not in accordance with its nature. The aim of the presented study is to compare the rate of animal aggression in relation to cases of documented aggression towards humans. The victims were investigated according to the age, gender and types of injuries caused by animal bites. The protocols of autopsies (2,218) and medical-legal examinations (4,569) performed from 2004-2009 in the Department of Forensic Sciences in Poznań were analyzed. The selected data was studied using Microsoft Office Excel 2007 for Windows. Analysis revealed the presence of animal bite injuries in less than 1% of the deceased victims of aggression. The number of individuals who died as a result of animal bites varied from 1-4 a year, and in all cases these were postmortem injuries. Analysis of injuries among surviving victims of aggression showed animal bite injuries were present in 41 out of 4,569 victims, almost equally among males and females. Moreover, in 25 victims the bite injuries recognized as human were found. The majority of animal bites occurred in adults. The medium injuries were the most frequent in the animal bite victims. Animal aggression is a marginal problem considering all cases of aggression towards humans. In contrast to the aggression of humans towards other humans, this is a very rare cause of human death or even major injury.

Human rabies: still a neglected preventable disease in Nigeria.

PubMed

Eke, C B; Omotowo, I B; Ukoha, O M; Ibe, B C

2015-01-01

Adequate surveillance and monitoring of dog bite incidents are veritable tools in the determination of the epidemiology of human rabies infections. There is a paucity of data with regards to rabies in Nigeria. Hence, this study was aimed at describing the pattern and outcomes of dog bites and rabies infections among patients presenting to University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu. This was a 10-year (January 1, 2004 to December 31, 2013) observational retrospective study. Case definition of rabies was based on ICD 10 criteria, while relevant clinical data were retrieved from individual folders of registered victims using a semi-structured questionnaire. Data were analyzed using SPSS version 17.0 while the level of statistical significance was set at P < 0.05. A total of 149 cases of dog bites were reported during the period under review, of which 6 (4.0%) had confirmed rabies. Ninety-six (64.4%) cases presented more than 24 h after the bites. Majority of the offending dogs were stray dogs 86 (57.7%), which attacked their victims unprovoked, in 54.6% of cases. Furthermore, most of the bites were from dogs with unknown history of rabies vaccination 72 (52.3%), while the case fatality rate was 100%. All the cases of rabies reported were as a result of bites from stray dogs with unknown history of rabies vaccinations, and the outcome was 100% fatality in all cases. Efforts should be made to create and strengthen awareness campaigns on control of rabies infections through responsible dog ownership including their regular vaccinations as well as provision and use of prompt postexposure prophylaxis in human cases of dog bites at all levels of health care.

The Dietary Intervention to Enhance Tracking with mobile (DIET Mobile) study: A six-month randomized weight loss trial

PubMed Central

Turner-McGrievy, Gabrielle M.; Wilcox, Sara; Boutté, Alycia; Hutto, Brent E.; Singletary, Camelia; Muth, Eric R.; Hoover, Adam

2017-01-01

Objective To examine the use of two different mobile diet self-monitoring methods for weight loss. Methods Overweight adults (n=81; mean BMI 34.7±5.6 kg/m2) were randomized to self-monitor their diet with a mobile app (App, n=42) or wearable Bite Counter device (Bite, n=39). Both groups received the same behavioral weight loss information via twice weekly podcasts. Weight, physical activity (International Physical Activity Questionnaire), and energy intake (2 dietary recalls) were assessed at 0, 3, and 6 months. Results At six months, 75% of participants completed the trial. The App group lost significantly more weight (-6.8±0.8 kg) than the Bite group (-3.0±0.8 kg; group×time interaction: P<0.001). Changes in energy intake (-621±157 App, -456±167 Bite; P=0.47) or number of days diet was tracked (90.7±59.2 App, 68.4±61.2 Bite; P=0.09) did not differ between groups, but the Bite group had significant increases in physical activity METs min/wk (+2015.4±684.6; P=0.02) compared to little change in the App group (-136.5±630.6; P=0.02). Total weight loss was significantly correlated with number of podcasts downloaded (r=-0.33, P<0.01) and number of days diet was tracked (r=-0.33, P<0.01). Conclusions While frequency of diet tracking was similar between the App and Bite groups, there was greater weight loss observed in the App group. PMID:28600833

Medico-legal significance of the identification of offending snake in a fatal snake bite: a case report.

PubMed

Silva, Anjana; Gamlaksha, Dayal; Waidyaratne, Dhananjaya

2013-11-01

A 19 year old male was admitted to a tertiary care centre in Sri Lanka, with a history of snake bite while sleeping at night. A killed specimen of a snake was brought with the patient. It had been identified as a non-venomous snake by the doctor and handed over to relatives, with a comment to that effect. Patient had no clinical or laboratory evidence of envenoming on admission. Patient developed bilateral ptosis six hours after alleged snake bite, soon followed by respiratory paralysis and was treated with Indian polyvalent anti-venom serum. After 12 h of the bite, patient had developed hypotension that did not respond to ionotropes. Despite intensive management, patient had become deeply comatose and deceased 46 h following the snake bite. Autopsy revealed features suggestive of disseminated intravascular coagulation. Since an allegation of medical negligence too had been levelled by the relations of the patient against the clinical staff, the buried specimen of the snake was recovered by police, on a judicial order, a week later. It was found to be almost completely disintegrated and only the scales and bones were remaining. According to the scale characters, the reconstructed specimen was identified as Indian krait (Bungarus caeruleus). Authentication of snake is important in investigating a death due to snake bite, especially when the snake was initially claimed to be a non-venomous snake. This case suggests the usefulness of forensic identification of species of the snake in investigating suspected snake bite cases. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Tail Biting Trellis Representation of Codes: Decoding and Construction

NASA Technical Reports Server (NTRS)

Shao. Rose Y.; Lin, Shu; Fossorier, Marc

1999-01-01

This paper presents two new iterative algorithms for decoding linear codes based on their tail biting trellises, one is unidirectional and the other is bidirectional. Both algorithms are computationally efficient and achieves virtually optimum error performance with a small number of decoding iterations. They outperform all the previous suboptimal decoding algorithms. The bidirectional algorithm also reduces decoding delay. Also presented in the paper is a method for constructing tail biting trellises for linear block codes.

Skeletal Class III and anterior open bite treatment with different retention protocols: a report of three cases.

PubMed

Farret, Milton Meri Benitez; Farret, Marcel Marchiori; Farret, Alessandro Marchiori

2012-09-01

The treatment of skeletal class III and anterior open bite can be unstable and orthodontists frequently observe relapse. Here, we report on the management of three patients with skeletal class III profiles and open bites treated by orthodontic camouflage. Each received a retention protocol involving the use of two separate appliances during the night and day accompanied by myofunctional therapy. Long-term follow-up revealed a stable outcome.

An Annotated Checklist of the Anopheles of Thailand (Diptera : Culicidae) (Thai National Scientific Papers, Fauna Series Number 2)

DTIC Science & Technology

1968-08-01

workers in 1958 on Doi Suthep mountain near Chiang Mai . Additional specimens in the SEATO collection were made by human biting collections, or...to be restricted to forested hills. The specimens taken in the human biting collections at Chiang Mai \\vere not permitted to engorge, and the biting...ditches, seepages, and sumps. Distribution in Thailand: Ayutthaya, Chanthaburi, Chiang Mai , Chon Buri, Phra Nakhon (Bangkok), Nakhon Nayok, Nakhon

An Investigation of the Posterior Component of Occlusal Force

DTIC Science & Technology

1994-05-01

of the hemostat allowed subjects to consistently orient the bite force transducer parallel to the occIusal plane , thus allowing the bite force to be...the anterior component of occlusal force was influenced by the steepness of the occlusal plane . Southard et al (1989) was the first to quantify the...young adult males yielded higher mean maximum bite forces at 20 mm opening and at 40 mm opening. The authors suggested that orientation and function of

Screening of Oomycete Fungi for Their Potential Role in Reducing the Biting Midge (Diptera: Ceratopogonidae) Larval Populations in Hervey Bay, Queensland, Australia

PubMed Central

Stephen, Kirsty; Kurtböke, D. Ipek

2011-01-01

Biting midges are globally distributed pests causing significant economic losses and transmitting arbovirus diseases to both animals and humans. Current biological and chemical control strategies for biting midge target destruction of adult forms, but strategies directed at immature stages of the insect have yet to be explored in Australia. In the present study, coastal waters of Hervey Bay region in Queensland, Australia were screened to detect the habitats of biting midge at immature stages. These results were then correlated to local environmental conditions and naturally occurring entomopathogenic fungal flora, in particular the Oomycete fungi, to determine their reducing effect on insect immature stages in the search for biological control agents in the region. The dominant species of biting midge found within this study was Culicoides subimmaculatus occuring between mean high water neaps and mean high water spring tide levels. Within this intertidal zone, the presence of C. subimmaculatus larvae was found to be influenced by both sediment size and distance from shore. Halophytophthora isolates colonized both dead and alive pupae. However, the association was found to be surface colonization rather than invasion causing the death of the host. Lack of aggressive oomycete fungal antagonists towards midge larvae might correlate with increased incidences of biting midge infestations in the region. PMID:21655137

Activity in the premotor area related to bite force control--a functional near-infrared spectroscopy study.

PubMed

Takeda, Tomotaka; Shibusawa, Mami; Sudal, Osamu; Nakajima, Kazunori; Ishigami, Keiichi; Sakatani, Kaoru

2010-01-01

The purpose of this study was to elucidate the influence of bite force control on oxygenated hemoglobin (OxyHb) levels in regional cerebral blood flow as an indicator of brain activity in the premotor area. Healthy right-handed volunteers with no subjective or objective symptoms of problems of the stomatognathic system or cervicofacial region were included. Functional near-infrared spectroscopy (fNIRS) was used to determine OxyHb levels in the premotor area during bite force control. A bite block equipped with an occlusal force sensor was prepared to measure clenching at the position where the right upper and lower canine cusps come into contact. Intensity of clenching was shown on a display and feedback was provided to the subjects. Intensity was set at 20, 50 and 80% of maximum voluntary teeth clenching force. To minimize the effect of the temporal muscle on the working side of the jaw, the fNIRS probes were positioned contralaterally, in the left region. The findings of this study are: activation of the premotor area with bite force control was noted in all subjects, and in the group analysis OxyHb in the premotor cortex was significantly increased as the clenching strengthened at 20, 50 and 80% of maximum voluntary clenching force. These results suggest there is a possibility that the premotor area is involved in bite force control.

Tips to Prevent Tick Bites

EPA Pesticide Factsheets

Using the right insect repellent and other preventive actions can discourage ticks, mosquitoes, and other biting insects from landing on you. Tips include avoiding tick habitats and minimizing exposed skin.

First Aid: Animal Bites

MedlinePlus

... First Aid: Skin Infections Cat Scratch Disease Preventing Dog Bites Rabies Staying Safe ... All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, ...

Rat-bite fever

MedlinePlus

Streptobacillary fever; Streptobacillosis; Haverhill fever; Epidemic arthritic erythema; Spirillary fever; Sodoku ... Rat-bite fever can be caused by either of 2 different bacteria, Streptobacillus moniliformis or Spirillum minus. Both of these are ...

Impetigo

MedlinePlus

... is already irritated by another problem, such as eczema , poison ivy , insect bites , and cuts or scrapes . ... injuries (cuts, scrapes, bug bites, etc.), areas of eczema, and rashes such as poison ivy. Keep these ...

Cats

MedlinePlus

... bites and scratches: Be cautious with unfamiliar animals. Approach cats with care, even if they seem friendly. ... more than 5 years since your last tetanus shot. Report the bite to animal control or your ...

Prognathism

MedlinePlus

... provider if: You have difficulty talking, biting, or chewing related to the abnormal jaw alignment. You have ... jaw shape? Is there difficulty talking, biting, or chewing? What other symptoms do you have? Diagnostic tests ...

Biting

MedlinePlus

... the timeout has ended. Creating a 'Bite-Free' Environment Whether you feel like you've made progress ... before you go. If a larger, more chaotic environment seems overwhelming, you might consider putting your child ...

Differences in bite force between dolichofacial and brachyfacial individuals: Side of mastication, gender, weight and height.

PubMed

Quiudini, Paulo Roberto; Pozza, Daniel Humberto; Pinto, Ary Dos Santos; de Arruda, Mauricio Ferraz; Guimarães, Antonio Sergio

2017-07-01

Due to the bite force importance in functionality of the masticatory system, this study aimed to characterize it in dolichofacial and brachyfacial individuals. A sample comprised by 190 patients was divided into two groups: 90 severe dolichofacial, and 100 severe brachyfacial individuals classified according to the VERT index and the face height ratio (Jarabak quotient). Bite force was measured by using an adjusted digital dynamometer and proper methodology. The sample met the parametric assumptions and presented statistical significance when right and left sides of dolichofacial and brachyfacial individuals were compared. However, within the same group, no differences between the left and right sides were found. Generally, bite force was higher for male, left masticator, age between 41-50 years, weighing over 100kg and between 1.81 and 1.90m tall. Based on the results of this cross-sectional study, it was possible to conclude that the bite force in severe brachyfacial individuals was significantly higher than in severe dolichofacial individuals, being influenced by gender, weight and height. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

First report of transmission of canine leishmaniosis through bite wounds from a naturally infected dog in Germany.

PubMed

Naucke, Torsten J; Amelung, Silke; Lorentz, Susanne

2016-05-10

Canine leishmaniosis (CanL) is an important zoonosis caused by Leishmania (L.) infantum. Transmission of L. infantum to dogs (and humans) is mainly through the bite of infected sandflies, but the parasite can also be transmitted vertically, venereally and through blood transfusions of infected donors. Additionally, the direct dog-to-dog transmission through bites or wounds is suspected. In December 2015, a female eight-year-old Jack-Russell-Terrier was tested positive for CanL in Germany (ELISA 74, IFAT 1:4.000). The dog had never been in an endemic area, had never received a blood transfusion and had never been used for breeding. Another female Jack-Russell-Terrier (born 2009 in Spain) was kept in the same household between 2011 and 2012. That dog was imported to Germany in 2011 and was tested positive for leishmaniosis in 2012. The Spanish-born dog had received several bite wounds, i.a. in the neck, during fights with the German-born Terrier. This may be the first report of transmission of L. infantum through bite wounds from a naturally infected dog in Germany.

Aggressive behavior and performance in the Tegu lizard Tupinambis merianae.

PubMed

Herrel, Anthony; Andrade, Denis V; de Carvalho, José Eduardo; Brito, Ananda; Abe, Augusto; Navas, Carlos

2009-01-01

Aggression is an important component of behavior in many animals and may be crucial to providing individuals with a competitive advantage when resources are limited. Although much is known about the effects of catecholamines and hormones on aggression, relatively few studies have examined the effects of physical performance on aggression. Here we use a large, sexually dimorphic teiid lizard to test whether individuals that show high levels of physical performance (bite force) are also more aggressive toward a potential threat (i.e., a human approaching the lizard). Our results show that independent of their sex, larger individuals with higher bite forces were indeed more aggressive. Moreover, our data show that individuals with higher bite forces tend to show decreased escape responses and are slower, providing evidence for a trade-off between fight and flight abilities. As bite force increased dramatically with body size, we suggest that large body size and bite force may reduce the threshold for an individual to engage in an aggressive encounter, allowing it to potentially gain or maintain resources and fight off predators while minimizing the risk of injury.