Fujita, Shuhei; Ide, Yoshinobu; Abe, Sinichi
To clarify variations of vascular distribution around the mandibular anterior tooth lingual region, an area in which vascular injuries have often been reported during dental implant surgery. The reasons for such injuries in this region are discussed from an anatomical perspective. Anatomical dissections were performed on 100 sides of 50 cadavers used for anatomy education. Ten sides of 5 cadavers were injected intravascularly with methyl methacrylate, and penetration of the mandible was closely evaluated. In the mandibular anterior tooth lingual region, both the sublingual and submental arteries showed various distribution patterns. Distal branches basically penetrated the bone. In the mandibular anterior tooth lingual region, the sublingual and submental arteries traveled from the vicinity of the mylohyoid muscle attachment along the bone surface in an anterosuperior direction. Many of these blood vessels penetrated the alveolar mucosa in the anterior tooth region, and many distal branches of the vessels also finally penetrated the bone. This seems to explain why many vascular injuries are encountered around the mandibular anterior tooth lingual region during implant surgery.
Suh, Jennifer S; Billy, Edward J
It can be esthetically and financially daunting for patients to lose teeth in an anterior region of the mouth. For these patients, traditional treatment options presented in the past have included fixed partial denture, implants, and conventional removable partial denture (RPD). For patients faced with financial, anatomical, and/or esthetic limitations, the edentulous region can be restored successfully with a rotational path RPD. Rotational path RPD designs have often been overlooked by the dental profession due to its complex concepts involving the prosthetic design and sensitive laboratory techniques. With better understanding of the concepts and design, the dental clinician can deliver the highest esthetic outcome in compromised areas in which other treatment options may often face limitations. This paper reviews the method used to esthetically design and plan a posterior-anterior rotational path RPD in an edentulous mandibular anterior region for a patient missing the mandibular incisors. Due to inadequate understanding of the mechanics of rotational path RPDs, many clinicians have not adapted the application of this advantageous prosthesis. When correctly designed and fabricated, the rotational path RPD provides improved esthetics, cleanliness, and retention for patients who may not be suitable candidates for implants or fixed partial dentures in tooth-supported edentulous regions.
Kusum, Chandan Kumar; Mody, Pranav V.; Indrajeet; Nooji, Deviprasad; Rao, Suhas K.; Wankhade, Bhushan Ganesh
Implant surgery in mandibular anterior region may turn from an easy minor surgery into a complicated one for the surgeon, due to inadequate knowledge of the anatomy of the surgical area and/or ignorance toward the required surgical protocol. Hence, the purpose of this article is to present an overview on the: (a) Incidence of massive bleeding and its consequences after implant placement in mandibular anterior region. (b) Its etiology, the precautionary measures to be taken to avoid such an incidence in clinical practice and management of such a hemorrhage if at all happens. An inclusion criterion for selection of article was defined, and an electronic Medline search through different database using different keywords and manual search in journals and books was executed. Relevant articles were selected based upon inclusion criteria to form the valid protocols for implant surgery in the anterior mandible. Further, from the selected articles, 21 articles describing case reports were summarized separately in a table to alert the dental surgeons about the morbidity they could come across while operating in this region. If all the required adequate measures for diagnosis and treatment planning are taken and appropriate surgical protocol is followed, mandibular anterior region is no doubt a preferable area for implant placement. PMID:26288617
A contemporary approach for treatment planning of horizontally resorbed alveolar ridge: Ridge split technique with simultaneous implant placement using platelet rich fibrin membrane application in mandibular anterior region.
Parthiban, Prathahini S; Lakshmi, R Vijaya; Mahendra, Jaideep; Sreekumar, K; Namasivayam, Ambalavanan
Treatment of edentulous sites with horizontal atrophy represents a clinical situation in which the positioning of endosseous implants might be complex or sometimes impossible without a staged regenerative approach. This case report presents management of horizontally deficient mandibular anterior ridge with a contemporary approach to treatment planning and application of platelet-rich fibrin membrane for ridge split technique and simultaneous implant placement. Implants in anterior mandibular area are considered to be most predictable, stable, with high success rate and patients' satisfaction with implant esthetics. In contrast to traditional ridge augmentation techniques, ridge splitting allows for immediate implant placement following surgery and eradicates the possible morbidity from a second surgical site.
Maheshwari, P; Chandrashekhar, C; Radhakrishnan, R
Vascularized ameloblastoma is a bewildering entity whose existence is questionable from its origin to nosology and its very characterization as a distinct variant of ameloblastoma. This uncertainty is largely because of a fewer number of documented cases and loss of long-term follow-up. The current paper describes two cases of ameloblastoma in the mandibular anterior region, which had features of so-called "hemangiomatous ameloblastoma" as it was originally described. Understanding its pathophysiology based on various views and clinical implications in terms of its biologic behavior are brought to light in this paper.
Brose, M O; Tanquist, R A
The need for and use of anterior coupling in occlusal rehabilitation has been discussed. The anterior teeth can often be coupled to the posterior controls by modifying contours with selective grinding, full or partial coverage restorations, or composite. When anterior guidance is provided, the anterior teeth should harmonize with the TMJs so that the posterior teeth will disclude in excursive mandibular movements. Significant functional, esthetic, and phonetic alterations that change the anterior guidance must be carefully planned because the anterior guidance affects all excursive tooth contacts. Anterior coupling, as described, is often an overlooked entity in restorative dentistry. Evidence of its role in separating the posterior teeth, reducing parafunctional activity, and harmonizing the temporomandibular complex has been presented.
Santini, L; Varoquaux, A; Giovanni, A; Dessi, P; Michel, J
Recurrent ameloblastoma with skull base invasion is a rare clinical entity with poor prognosis. We report a case of a mandibular ameloblastoma recurrence involving the anterior skull base. The diagnostic and therapeutic processes are presented with emphasis on the radiologic features of ameloblastoma. Another aim of this case report is to underline the importance of close and long-term follow-up after resection. Ameloblastoma recurrences are frequent and mainly occur after incomplete surgical resection. These recurrences may be diagnosed late because of lack of symptoms in the mandibular area.
Nejaim, Yuri; de Freitas, Deborah Queiroz; de Oliveira Santos, Christiano
Purpose The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Materials and Methods Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. Results In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. Conclusion CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region. PMID:27672611
Yonchak, T.; Reader, A.; Beck, M.; Clark, K.; Meyers, W. J.
The purpose of this prospective, randomized, double-blind study was to measure the degree of anesthesia obtained with a labial infiltration of either 2% lidocaine with 1:50,000 or 2% lidocaine with 1:100,000 epinephrine in mandibular anterior teeth. Another objective was to measure the degree of anesthesia obtained with a lingual infiltration of 2% lidocaine with 1:100,000 epinephrine in mandibular anterior teeth. Through use of a repeated-measures design, 40 subjects randomly received a labial infiltration at the lateral incisor apex of either 1.8 mL of 2% lidocaine with 1:100,000 epinephrine or 1.8 mL of 2% lidocaine with 1:50,000 epinephrine at 2 separate appointments. An additional 40 subjects received a lingual infiltration at the lateral incisor apex of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine. The mandibular anterior teeth were blindly pulp tested at 4-minute cycles for 60 minutes postinjection. No response from the subject to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Anesthesia was considered successful when 2 consecutive 80 readings were obtained. For the 3 infiltrations, success rates for the lateral incisor ranged from 43 to 50%. Adjacent teeth had success rates of 27 to 63%. There was no significant difference (P > 0.05) in success between the labial infiltration of 2% lidocaine with 1:100,000 epinephrine and 2% lidocaine with 1:50,000 epinephrine or the lingual infiltration of 2% lidocaine with 1:100,000 epinephrine when compared with the labial infiltration of 2% lidocaine with 1:100,000 epinephrine. Duration of pulpal anesthesia declined steadily for all solutions over the 60 minutes. In conclusion, the success rate of 43-50% and declining duration of pulpal anesthesia over an hour indicates that a labial infiltration of 1.8 mL of either 2% lidocaine with 1:100,000 epinephrine or 1: 50,000 epinephrine or a lingual infiltration of 2% lidocaine with 1:100,000 epinephrine over the
Pascual, Andrés; Barallat, Lucía; Santos, Antonio; Levi, Paul; Vicario, Mónica; Nart, José; Medina, Kyrenia; Romanos, Georgios E
Periodontal biotype is a key element influencing esthetic treatment outcomes in clinical practice. However, while the soft and hard tissue thicknesses of maxillary anterior teeth have been widely studied, information regarding mandibular anterior teeth is scarce. Therefore, the aim of this study was to determine whether there is a relationship in terms of hard and soft tissue thickness between maxillary and mandibular anterior teeth. The present study included 90 maxillary and 90 mandibular anterior teeth in 15 healthy patients. Clinical and cone beam computed tomography measurements were taken to determine gingival and buccal bone thickness, respectively, and a correlation was made between maxillary and mandibular anterior teeth. No statistically significant differences were found when comparing gingival and buccal bone thickness at the crestal third and midpoint of maxillary and mandibular teeth (P > .05). However, some differences were observed at the apical third between the two groups. The results suggest that soft and hard tissue dimensions of maxillary and mandibular anterior teeth are comparable, especially in the coronal third. However, more studies are necessary to confirm that maxillary anterior teeth can be used as a reference when dealing with mandibular incisors and canines.
de Andrade, Oswaldo Scopin; Ferreira, Luiz Alves; Hirata, Ronaldo; Rodrigues, Flavia Pires; D'Alpino, Paulo Henrique Perlatti; Di Hipolito, Vinicius
The use of ceramic veneers to restore crowded teeth in the maxilla has been widely discussed in the literature. However, the use of this technique in the mandible has received little attention. Therefore, this case report describes the treatment of crowded mandibular anterior teeth using ceramic veneers. The primary treatment challenge in this region is the reduced tooth structure available for rehabilitation. Proper communication between the clinician and dental technician is required to achieve clinical success. This article presents a straightforward treatment plan and restorative technique that includes both the clinical and laboratory sequences necessary for predictable and stable postoperative outcomes.
Le Cabec, Adeline; Kupczik, Kornelius; Gunz, Philipp; Braga, José; Hublin, Jean-Jacques
Tooth root length has been shown to taxonomically distinguish Neanderthals from modern humans. However, this may result from differences in jaw size between both taxa, although most previous studies have revealed a very low or non-existent correlation between tooth size and jaw size in recent modern humans. We therefore investigated, within a broader taxonomical frame, to what extent measurements on the anterior tooth roots and the symphyseal region covary. Our samples comprise permanent mandibular incisors and canines from Mauer, Neanderthals, and extant and fossil modern humans sensu lato. Using micro-computed tomography, we took linear and cross-sectional surface area measurements of the roots and the symphyseal region and calculated the root volume. We also measured 3D landmarks to quantify the overall size of the mandible using centroid size. Furthermore, we analyzed the relationship between root size and symphyseal shape, based on Procrustes shape variables of semi-landmarks along the symphyseal outline. Our results show that Neanderthals have significantly larger anterior tooth roots than recent modern humans in terms of root length, mid-sagittal surface area and volume, even after correction for mandibular size. In contrast, symphyseal height and width do not differ significantly between both taxa, whereas, without scaling, the mid-sagittal symphyseal surface area and the centroid size of the mandible do differ. Importantly, no significant correlation was found between any of the root and symphyseal measurements after correction for overall mandibular size. The shape analyses revealed that Neanderthals have a vertical symphyseal profile with an evenly-thick symphysis, whereas recent modern humans display an unevenly-thick symphysis, comprising a pronounced incurvatio mandibularis and a bony chin. These results suggest a negative evolutionary allometry for the recent modern human anterior root size. Therefore, root length and other root dimensions can be
Sun, Hook; Ah Lee, Kyung; Kim, Jin Woo; Kim, Young Hwan; Yun, Sung Ho
Advancement genioplasty to achieve aesthetic improvement was performed; however, the more genioplasty was advanced, the worse the depth of the labiomental fold became. Therefore, our hospital applied not only advancement of genioplasty but also rotational advancement of anterior segmental osteotomy (ASO) for satisfactory aesthetic lines. From January 2008 to March 2010, our hospital operated on 10 patients who showed not only convexity profile with posterior divergent but also small SNB and microgenia in the cephalometric analysis. Their mean age was 24.8 years, and we had them followed up for at least 6 months. The surgical technique was contrary to the ASO setback, which means a rotational advancement and an average 5-mm advancement of the ASO segment, adding an average of 6- to 7-mm advancement of genioplasty. Postoperative results in the cephalometric analysis showed a good balance of the lower part of the face. Average SNB was increased from 69.96 to 72.88 degrees. The pogonion of the soft tissue came forward on an average of 7.18 mm and superiorly on an average of 1.93 mm. The inclination of L(1)MP was decreased from 100.00 to 91.99 degrees, but it was within the reference range. The labiomental fold was not deeper. We checked that spaces created by the anterior segmental osteotomy and advancement of genioplasty were filled with new bone through follow-up x-ray density images. If balance of the lower part of the face with mandibular retrusion is insufficient using advancement of genioplasty, our hospital also applied rotational advancement of ASO. This operative technique not only was relatively simple and applied less pressure but also made a new B point.
Korath, Vinoth Abraham; Nagachandran; Vijayalakshmi, Devaki; Parameswaran, Ratna; Raman, Priya; Sunitha, Catherine; Khan, Nayeemullah
Introduction One of the major limiting factors in retraction of proclined teeth is the width of the alveolus both in maxilla and mandible. Aim The objective of this study was to assess the maxillary and mandibular anterior alveolar dimensions and to correlate with mandibular divergence in Class I bi-dento-alveolar protrusion patients. Materials and Methods Pretreatment lateral cephalograms (n=88) were analysed using a composite analysis with cephalometric software. Both maxillary and mandibular anterior alveolar widths and heights were measured and correlated with mandibular divergence. One-way analysis (ANOVA) and Pearson correlation test were used to compare and establish the significance between groups. Results Segregation of the data based on variation in the bi-cortical widths and heights showed that lesser alveolar widths and greater alveolar heights were associated with the high angled subjects and greater alveolar widths and lesser heights were associated with low angled subjects. Conclusion Patients with hyperdivergent mandible exhibited thin anterior alveolar width and greater alveolar height whereas low angled subjects had wider alveolar width and lesser alveolar height. Orthodontic treatment plan for retraction of anterior teeth must be based on these differences caused by variations in mandibular divergence. PMID:27437356
do Nascimento, Eduarda Helena Leandro; dos Anjos Pontual, Maria Luiza; dos Anjos Pontual, Andréa; da Cruz Perez, Danyel Elias; Figueiroa, José Natal; Frazão, Marco Antônio Gomes
Purpose Sufficient area in the interforaminal region is required for dental implant placement, and the anterior loop of the mandibular canal is located within the limits of this area. The aim of this study was to evaluate the prevalence and extent of the anterior loop in a Brazilian sample population using cone-beam computed tomography (CBCT). Materials and Methods CBCT images from 250 patients (500 hemimandibles) obtained for various clinical indications were randomly selected and evaluated to determine the presence and length of the anterior loop. The length of the anterior loop was then compared based on gender, age, and the side of the mandible. The data were analyzed using the Pearson chi-square test and linear regression analysis. Results An anterior loop was identified in 41.6% of the cases, and its length ranged from 0.25 mm to 4.00 mm (mean, 1.1±0.8 mm). The loop had a greater mean length and was significantly more prevalent in males (p=0.014). No significant differences were found between the right and left sides regarding length (p=0.696) or prevalence (p=0.650). Conclusion In this study, a high prevalence of the anterior loop of the mandibular canal was found, and although its length varied greatly, in most cases it was less than 1 mm long. Although this is a prevalent anatomical variation, safety limits for the placement of implants in this region cannot be established before an accurate evaluation using imaging techniques in order to identify and preserve the neurovascular bundles. PMID:27358813
Barde, Dhananjay H; Mudhol, Anupama; Ali, Fareedi Mukram; Madan, R S; Kar, Sanjay; Ustaad, Farheen
Background: Mandibular fractures are treated surgically by either rigid or semi-rigid fixation, two techniques that reflect almost opposite concept of craniomaxillofacial osteosynthesis. The shortcomings of these fixations led to the development of 3 dimensional (3D) miniplates. This study was designed with the aim of evaluating the efficiency of 3D miniplate over Champys miniplate in anterior mandibular fractures. Materials & Methods: This study was done in 40 patients with anterior mandibular fractures. Group I consisting of 20 patients in whom 3D plates were used for fixation while in Group II consisting of other 20 patients, 4 holes straight plates were used. The efficacy of 3D miniplate over Champy’s miniplate was evaluated in terms of operating time, average pain, post operative infection, occlusion, wound dehiscence, post operative mobility and neurological deficit. Results: The mean operation time for Group II was more compared to Group I (statistically significant).There was significantly greater pain on day of surgery and at 2nd week for Group II patients but there was no significant difference between the two groups at 4th week. The post operative infection, occlusal disturbance, wound dehiscence, post operative mobility at facture site, neurological deficit was statistically insignificant (chi square test). Conclusion: The results of this study suggest that fixation of anterior mandibular fractures with 3D plates provides three dimensional stability and carries low morbidity and infection rates. The only probable limitation of these 3D plates may be excessive implant material, but they seem to be easy alternative to champys miniplate. How to cite the article: Barde DH, Mudhol A, Ali FM, Madan RS, Kar S, Ustaad F. Efficacy of 3-Dimensional plates over Champys miniplates in mandibular anterior fractures. J Int Oral Health 2014;6(1):20-6. PMID:24653598
Sun, Zongyang; Tee, Boon Ching
Periosteal growth at human mandibular ramus is characterized by bone apposition at the posterior border and resorption at the anterior border. Molecular control of this regional variation is unclear. This study examined the expression of several molecules involved in bone apposition/resorption at these regions in vivo and in vitro. By using growing pigs as a model, the periosteal growth was assessed at the mandibular ramus by vital staining and histological observations. In parallel, periosteal tissues were harvested and pulverized for RNA and protein extraction. Periosteal cells were also isolated, expanded in osteogenic media, and subjected to a single dose of dynamic tensile strain (0, 5, or 10% magnitude at 0.5 Hz) to examine their responses to mechanical loading. Real-time RT-PCR and Western blot analyses were used to examine mRNA and protein expression from periosteal tissues and cultured cells. Histological observation confirmed an anterior-resorption/posterior-apposition pattern in the pig mandibular ramus. Both in vivo tissue and in vitro cells demonstrated greater mRNA expression of receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) ratio and bone morphogenetic protein 2 (BMP2) at the anterior region, while OPG expression at the anterior region was lower than the posterior region. In response to the application of a single dose of dynamic tensile strain, cultured periosteal cells appeared to change the expression profile of osteogenic markers but not that of RANKL/OPG and BMP2. These findings suggest that the unique regional variation of periosteal activity at the mandibular ramus is regulated by a differential expression of RANKL/OPG ratio (likely through differential induction of OPG) and BMP2.
Al-Mahdy Al-Belasy, F
A modification of the secondary epithelization vestibuloplasty technique described by Kazanjian that eliminates the sharp V in the depth of the extended vestibule and counteracts shallowing of the sulcus is presented. Ten consecutive patients indicated for anterior mandibular secondary epithelization vestibuloplasty were treated. A bipedicled mucosal flap was developed in the labioalveolar mucosa for lining the extended vestibular depth. A comparison was made of the vestibular depth measured from the crest of the ridge to the junction of the attached mucosa both preoperatively and postoperatively. Healing of raw surfaces was uneventful. The mean preoperative anterior mandibular vestibular depth was 3.5+/-1.1 mm. After 6 months, the mean anterior mandibular vestibular depth was 9.2+/-1.7 mm, a statistically significant difference (P < .05). The mean gain in vestibular depth was 5.7+/-2.2 mm. Overcorrection is unnecessary with this modification. Elimination of the sharp V in the extended vestibular depth enables denture fabrication with better flange extension and improved oral hygiene.
Mehta, Shamir B; Francis, Selar; Banerji, Subir
The successful management of the worn mandibular anterior dentition may present an awkward challenge to the dental operator. The purpose of this article is to describe a case report illustrating the use of a guided, three-dimensional protocol for the ultra-conservative and predictable restoration of the worn lower anterior dentition using direct resin composite. This technique utilizes information based on established biomechanical and occlusal principles to fabricate a diagnostic wax-up, which is duplicated in dental stone. This is used to prepare a vacuum-formed modified stent, assisting the clinician to place directly bonded resin composite restorations to restore the worn lower anterior dentition. The technique, described in 2012 and referred to as 'injection moulding' has the potential to offer optimal form, function and an aesthetic outcome in an efficient manner. CPD/Clinical Relevance: This article aims to describe an alternative technique to simplify the processes involved with restoration of worn lower anterior teeth.
Takasugi, Y.; Furuya, H.; Moriya, K.; Okamoto, Y.
The conventional inferior alveolar nerve block (conventional technique) has potential risks of neural and vascular injuries. We studied a method of inferior alveolar nerve block by injecting a local anesthetic solution into the pterygomandibular space anterior to the mandibular foramen (anterior technique) with the purpose of avoiding such complications. The insertion angle of the anterior technique and the estimation of anesthesia in the anterior technique were examined. The predicted insertion angle measured on computed tomographic images was 60.1 +/- 7.1 degrees from the median, with the syringe end lying on the contralateral mandibular first molar, and the insertion depth was approximately 10 mm. We applied the anterior technique to 100 patients for mandibular molar extraction and assessed the anesthetic effects. A success rate of 74% was obtained. This is similar to that reported for the conventional technique but without the accompanying risks for inferior alveolar neural and vascular complications. Images Figure 2 PMID:11432177
Joss, C U; Triaca, A; Antonini, M; Kuijpers-Jagtman, A M; Kiliaridis, S
Neurosensory status and craniomandibular function of 19 patients (mean age 35.2 years, range 17.8-58.8 years) treated by combined surgical orthodontic treatment with distraction osteogenesis of the mandibular anterior alveolar process (DO group) was compared with that in 41 orthodontically treated patients (mean age 22.9 years, range 15.1-49.0 years; control group). Clinical examination took place on average 5.9 years (DO group) and 5.4 years (control group) after treatment ended. Neurosensory status was determined by two-point discrimination (2-pd) and the pointed and blunt test. Lateral cephalograms evaluated advancement of the mandibular alveolar process and possible relapse. There was no significant difference in craniomandibular function and neurosensory status between the groups. Age was significantly correlated with 2-pd at the lips (DO: p=0.01, R=0.575; control group: p=0.039, R=0.324) and chin (DO: p=0.029, R=0.501; control group: p=0.008, R=0.410). Younger patients had smaller 2-pd values. Gender, age, the amount of advancement, and relapse at point B or incision inferior show no correlation with craniomandibular function and neurosensory impairment. DO of the mandibular anterior alveolar process is a valuable and safe method with minor side effects regarding neurosensory impairment.
Sarkar, Reena Bhola; Grewal, Jessica; Grewal, Ripin; Bansal, Arun
Adenomatoid odontogenic tumour is an uncommon, benign, hamartomatous lesion that commonly affects the anterior maxilla and has two radiographic variants, follicular and extrafollicular where the former is more common than the latter. Here, we report a case of 15-year-old female with midline swelling of the mandible. Radiographically, impacted right permanent mandibular canine was associated with the radiolucent lesion. Dentigerous cyst was given as provisional diagnosis. However, histologically the lesion represented the features of cystic variant of Adenomatoid odontogenic tumour. PMID:25121073
Baik, Un-Bong; Chun, Youn-Sic; Jung, Min-Ho; Sugawara, Junji
In a young woman, aged 18 years 8 months, who had an anterior open bite and anterior spacing, the right and left mandibular first molar extraction spaces were closed by protraction of the second and third molars without reciprocal retraction of the incisors and the premolars. The amounts of protraction for the second molars were 12 mm on the right side and 11 mm on the left side. Two miniscrews were inserted into the mesiobuccal side of the edentulous spaces, and 2 more screws were inserted into the anterior sites after removing previous miniscrews. In addition, 4 miniscrews were inserted into the buccal and palatal sides between the first and second maxillary molars to intrude the maxillary posterior teeth, which had extruded into the missing mandibular spaces. Careful biomechanical consideration was used to prevent extrusion of the molars and worsening of the anterior open bite from protraction of the posterior teeth. Ultimately, the anterior open bite was corrected by both intrusion of the maxillary molars and extrusion of the maxillary anterior teeth. Excellent occlusion and correction of the anterior open bite were achieved without tipping, rotation of the posterior teeth, or other problems. The right mandibular third molar, which had been impacted at the beginning of treatment, erupted into the second molar space and functioned properly. At the 1-year follow-up examination, the patient had a slight anterior open bite, but closure of the first molar extraction spaces was well maintained.
Krekmanov, L; Andersson, L; Ringqvist, M; Wilhelmsson, B; Walker-Engström, M L; Tegelberg, A; Ringqvist, I
In a prospective randomized study on treatment of obstructive sleep apnea syndrome, anterior-inferior mandibular osteotomy with the purpose of stretching the suprahyoidal muscle was performed as one of the treatment methods. Ten men aged 20 to 65 years, without cardiovascular or neurologic disease, with normal maxillomandibular relation, and having an apnea index between 5 and 25 were included in the study. After a specially designed osteotomy of the chin, the anterior suprahyoidal muscles were detached, stretched approximately 10 to 12 mm, and sutured. The chin was then placed in its original position and post-operative evaluation was performed. Although there were initial reports of decreased daytime sleepiness and less snoring after surgery, the results after 12 months were discouraging. Somnographic registration (apnea index, apnea/hypopnea index, and oxygen desaturation index) as well as cephalometric analysis failed to show positive results. Hence, suspension of the suprahyoidal muscles as a method of treatment for obstructive sleep apnea syndrome cannot be recommended.
Seo, Yu-Jin; Lin, Lu; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald
This case report presents the camouflage treatment that successfully improved the facial profile of a patient with a skeletal Class III malocclusion using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy. The patient was an 18-year-old woman with chief complaints of crooked teeth and a protruded jaw. Camouflage treatment was chosen because she rejected orthognathic surgery under general anesthesia. A hybrid type of bone-borne rapid maxillary expander with palatal mini-implants was used to correct the transverse discrepancy, and a mandibular anterior subapical osteotomy was conducted to achieve proper overjet with normal incisal inclination and to improve her lip and chin profile. As a result, a Class I occlusion with a favorable inclination of the anterior teeth and a good esthetic profile was achieved with no adverse effects. Therefore, the hybrid type of bone-borne rapid maxillary expander and a mandibular anterior subapical osteotomy can be considered effective camouflage treatment of a skeletal Class III malocclusion, providing improved inclination of the dentition and lip profile. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Obwegeser, Joachim Anton; Metzler, Philipp; Jacobsen, Christine; Zemann, Wolfgang
Segmental distraction osteogenesis of the anterior mandibular alveolar process (frontblock) is a sufficient method to avoid extractions in patients with dental crowding and to decompensate retroalveolism. Up to now dental-borne devices were used, but limitate the indications for front-block distraction. A new bone-borne distraction device for mandibular alveolar front-block movement is introduced in this study. The distractor allows sufficient segmental transport without loading on the teeth. Clinical evaluations of 7 patients have been performed including the feasibility and predictability of the distraction, postoperative pain and patients' discomfort. The results indicate that this technique is a promising strategy in the correction of dental crowding, correcting the curve of Spee and to decompensate mandibular retroalveolism even in patients with impaired periodontal health and a thin mandibular symphysis. Copyright © 2012 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
Tonge, E.A.; Heath, J.K.; Meikle, M.C.
Anterior displacement of the mandible was produced in twenty-eight 1-month-old female rats by two methods: (1) cast-gold splints cemented to the maxillary incisor teeth and (2) a removable stainless steel mesh appliance worn 6 hours each day, during which time the animals were sedated. The controls were littermates without appliances and in the mesh group were also sedated. Animals in the splint group were killed after 24 hours, 1 week, and 1 month; those in the mesh group were killed after 24 hours and after 1 week. the condyles were removed and cultured for 24 hours in medium containing /sup 3/H-thymidine. One condyle from each animal was processed for routine histologic and autoradiographic study. The other was digested in phosphate-buffered saline containing RNA-ase and pronase, and the specific activity of /sup 3/H-thymidine incorporation expressed as dpm/microgramDNA. Anterior mandibular displacement produced by both methods failed to result in a significant increase in the incorporation of /sup 3/H-thymidine into explant DNA. In the 7-day mesh experiment, however, there was a significant increase in the DNA content of the condylar explants from the displacement group, suggesting an increase in the cell population. This finding should be treated with caution because of the small numbers of animals involved, but it indicates an important area for further study. Changes in the distribution of labeled cells within the proliferative zone (PZ) were also observed autoradiographically in the mesh group, but there was little to suggest that mandibular displacement was accompanied by a significant increase in cell division within the PZ. Remodeling changes affecting both the articular tissue and the subchondral bone were a characteristic feature of the 1-month bit plane group.
Parnia, Fereidoun; Hafezeqoran, Ali; Mahboub, Farhang; Mojaver-Kahnamoui, Haniye
Objectives: This study was conducted to assess appearance, visibility, location and course of anatomical landmarks in mandibular interforaminal region using cone-beam computed tomography (CBCT). Study design: A total of 96 CBCT examinations was re-evaluated to exploit anatomical landmarks. The examinations used the Promax 3D CBCT unit. A sole examiner carried out all the measurements. Visibilities of the anatomical landmarks were scored using a four-point rating scale. Results: The mandibular foramen, anterior loop, incisive canal and lingual foramen were observed in 100,84,83,49 % of the images, respectively. The mean size, diameter and width of anterior loop, incisive canal and lingual foramen were obtained 3.54± 1.41, 1.47±0.50 and 0.8 ± 0.09mm, respectively. Conclusion: It is not safe to recommend any definite distance mesially from the mental foramen. The diameter of the canals and foramens should be determined on a case-by-case basis to exploit the appropriate location for each individual. Key words:Anatomical landmarks, cone-beam computed tomography, implant surgery, radiographic evaluation, surgical complications. PMID:22143718
Uribe, Flavio; Davoody, Leyla; Mehr, Rana; Jayaratne, Yasas S N; Almas, Khalid; Sobue, Takanori; Allareddy, Veerasathpurush; Nanda, Ravindra
The aim of this clinical trial was to investigate the duration of mandibular-crowding alleviation with piezotome-corticision orthodontics compared with conventional orthodontics. Single-centre, two-arm parallel group randomized controlled trial. Orthodontic clinic at the University of Connecticut. The study was approved by the Institutional Review Board (IRB # 12-0147-2). Forty-one adult subjects from a single centre with more than 5mm of mandibular anterior crowding were randomly allocated using block randomization into experimental and control groups. The experimental group received a corticision procedure with a piezotome on the labial aspect of the mandibular incisors in conjunction to a self-ligation fixed orthodontic appliance. The control group received the self-ligation fixed orthodontic appliance and no corticision. Same archwire sequence (0.014 inch followed by 0.014 × 0.025 inch copper-nickel-titanium) was followed for both groups. Mandibular study casts taken every 4-5 weeks were used to assess changes in the irregularity index by blinded outcome assessors. The time to alignment was calculated in days. Twenty-nine subjects (16 experimental and 13 control) completed the study. Overall, no significant difference in the time required to correct mandibular crowding with piezotome-corticision assisted (102.1 ± 34.7 days; 95% CI, 83.6 to 120.6) and conventional orthodontics (112 ± 46.2 days; 95% CI, 84-139.9) was observed. No complications with treatment or unintended consequences were observed on any of the subjects. A high attrition rate. This randomized clinical trial found no evidence that piezotome-corticision assisted orthodontics was more efficient in alleviating mandibular anterior crowding. ClinicalTrials.gov, Identifier: NCT02026258. Division of Orthodontics, University of Connecticut. None.
Clark, Kenneth; Reader, Al; Beck, Mike; Meyers, William J.
The purpose of this prospective, randomized, blinded study was to measure the degree of pulpal anesthesia obtained with an inferior alveolar nerve (IAN) block followed by an infiltration in mandibular anterior teeth. Through use of a repeated-measures design, 40 patients randomly received 3 injection combinations at 3 separate appointments: an IAN block followed by a mock lingual infiltration and a mock labial infiltration, an IAN block followed by a mock lingual infiltration and a labial infiltration, and an IAN block followed by a mock labial infiltration and a lingual infiltration. Each IAN block used 3.6 mL of 2% lidocaine with 1:100,000 epinephrine, and each infiltration used 1.8 mL of 2% lidocaine with 1:100,000 epinephrine administered over the lateral incisor apex. Mandibular anterior teeth were blindly pulp tested at 2-minute cycles for 60 minutes following the IAN-infiltration injections. No response from the patient to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes and the 80 reading was sustained for 60 minutes. Anesthesia was considered a failure if 2 consecutive 80 readings were not obtained during the 60 minutes. The results of this study showed that 100% of the patients had lip numbness with all IAN blocks. For the lateral incisor, the success rate of the IAN block alone was 40% and the failure rate was 30%. For the IAN block plus labial infiltration, the success rate was 62% and the failure rate was 12% for the lateral incisor. There was a significant difference (P < .05) between the IAN block alone and the IAN block plus labial infiltration. In conclusion, a labial infiltration, over the lateral incisor apex, of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine following an IAN block significantly improved pulpal anesthesia for the lateral incisor compared with the IAN block alone. PMID:15384292
Kilinç, Yeliz; Erkmen, Erkan; Kurt, Ahmet
The aim of the current study was to comparatively evaluate the mechanical behavior of 3 different fixation methods following various amounts of superior repositioning of mandibular anterior segment. In this study, 3 different rigid fixation configurations comprising double right L, double left L, or double I miniplates with monocortical screws were compared under vertical, horizontal, and oblique load conditions by means of finite element analysis. A three-dimensional finite element model of a fully dentate mandible was generated. A 3 and 5 mm superior repositioning of mandibular anterior segmental osteotomy were simulated. Three different finite element models corresponding to different fixation configurations were created for each superior repositioning. The von Mises stress values on fixation appliances and principal maximum stresses (Pmax) on bony structures were predicted by finite element analysis. The results have demonstrated that double right L configuration provides better stability with less stress fields in comparison with other fixation configurations used in this study.
Fernandes, Luciana Quintanilha Pires; Nunes, Livia Kelly Ferraz; Alves, Luana Santos; Ribeiro, Felipe de Assis Carvalho; Capelli, Jonas
ABSTRACT Introduction: Digital dental models provide a more accurate and comprehensive assessment of orthodontic cases. Although this technique is quite promising, there are few three-dimensional measurements methods described in the literature. Objective: The aim of this study was to propose a method for assessing the degree of mandibular anterior dental crowding in the three planes of space, using digital dental models. Methods: Thirty dental casts were selected and scanned by Maestro 3D Dental Scanner and imported by Geomagic Qualify 2013 software. The degree of crowding was calculated by two examiners, based on the Little’s Irregularity Index, by means of the definition of axial, coronal and sagittal planes for each model. Intraexaminer analysis was performed with Dahlberg’s Formula (DF) and Intraclass Correlation Coefficients (ICC), and interexaminer analysis was performed with ICC and paired t-test. Results: The ICC showed an excellent agreement (p < 0.05) for all measurements, except for the intraexaminer and interexaminer in the Z-axis, in which it was found a moderate agreement. The DF showed a satisfactory accuracy with all measurements showing less than 1 mm difference. The paired t-test showed statistical difference between the examiners in two measurements, although it was clinical irrelevant. Conclusion: When comparing the three planes of space, the Z-axis showed the greatest variation in landmarks placement; however, overall, the present method seems precise and reproducible. PMID:28746489
Rafini, F.; Priaminiarti, M.; Sukardi, I.; Lessang, R.
The healing of periodontal splinting can be detected both with clinical and radiographic examination. In this study, the alveolar bone was evaluated by radiographic digital periapical analysis. Periodontal tooth splinting is periodontal support therapy used to prevent periodontal injury during repair and regeneration of periodontal therapy. Radiographic digital periapical analysis of alveolar bone in the mandibular anterior region with chronic periodontitis and 2/3 cervical bone loss after three months of periodontal splinting. Eighty four proximal site (43 mesial and 41 distal) from 16 patients with chronic periodontitis and treated with spinting were examined by taking periapical digital radiographic at day 1 and 91. The bone loss, bone density and utility of lamina dura were evaluated. The statistical analysis after three months evaluation using T-test for bone loss, Wilcoxon sign rank test for bone density and utility lamina dura showed no significantly differences (p<0.05) (p=0.44, 0.256 and 0.059). No radiographic change in bone loss, bone density and utility of lamina dura from chronic periodontitis with 2/3 alveolar bone loss after three months splinting.
Alajbeg, Iva Z.; Gikić, Marijana; Valentić-Peruzović, Melita
Objective Temporomandibular disorders (TMD) are the most common source of orofacial pain of a non-dental origin. The study was performed to investigate the therapeutic effect of the conventional occlusal splint therapy and the physical therapy. The hypothesis tested was that the simultaneous use of occlusal splint and physical therapy is an effective method for treatment of anterior disc displacement without reduction. Materials and Methods Twelve patients (mean age =30.5 y) with anterior disc displacement without reduction (according to RDC/TMD and confirmed by magnetic resonance imaging) were randomly allocated into 2 groups: 6 received stabilization splint (SS) and 6 received both physical therapy and stabilization splint (SS&PT). Treatment outcomes included pain-free opening (MCO), maximum assisted opening (MAO), path of mouth opening and pain as reported on visual analogue scale (VAS). Results At baseline of treatment there were no significant differences among the groups for VAS scores, as well as for the range of mandibular movement. VAS scores improved significantly over time for the SS&PT group (F=28.964, p=0.0001, effect size =0.853) and SS group (F=8.794, p=0.001, effect size =0.638). The range of mouth opening improved significantly only in the SS&PT group (MCO: F=20.971, p=0.006; MAO: F=24.014, p=0.004) (Figure 2). Changes in path of mouth opening differ significantly between the groups (p=0.040). Only 1 patient in SS&PT group still presented deviations in mouth opening after completed therapy while in the SS group deviations were present in 5 patients after completed therapy. Conclusion This limited study gave evidence that during the treatment period lasting for 6 months, the simultaneous use of stabilization splint and physical therapy was more efficient in reducing deviations and improving range of mouth opening than the stabilization splint used alone. Both treatment options were efficient in reducing pain in patients with anterior disc
Joss, C U; Triaca, A; Antonini, M; Kiliaridis, S; Kuijpers-Jagtman, A M
This study evaluated soft tissue changes in adult patients treated with distraction osteogenesis (DOG) of the anterior mandibular alveolar process and related it to different parameters. 33 patients (27 females; 6 males) were analysed retrospectively before surgery at T1 (17.0 days), after surgery at T2 (mean 6.5 days), at T3 (mean 24.4 days), and at T4 (mean 2.0 years). Lateral cephalograms were traced by hand, digitized, superimposed, and evaluated. Statistical analysis was carried out using Kolmogorov-Smirnov test, paired t test, Pearson's correlation coefficient, and linear backward regression analysis. 2 years postoperatively (T4), the net effect of the soft tissue at point B' was 100% of the advancement at point B whilst the lower lip (labrale inferior) followed the advancement of incision inferior to 46%. Increased preoperative age was correlated (p<0.05) with more horizontal backward movement (T4-T3) for labrale superior and pogonion'. Higher NL/ML' angles were significantly correlated (p<0.05) with smaller horizontal soft tissue change at point B'. Gender and the amount of skeletal and dental advancement were not correlated with postoperative soft tissue changes (T4-T3). DOG of the anterior mandibular alveolar process is a valuable alternative for mandibular advancement regarding soft tissue change and predictability.
Barros, Sérgio Estelita C; Janson, Guilherme; Torres, Fernando César; de Freitas, Marcos Roberto; de Almeida, Renato Rodrigues
This case report describes the orthodontic treatment of a patient with a deep-overbite Angle Class I malocclusion, agenesis of a mandibular central incisor, and 2 supernumerary teeth, which caused impaction of the mandibular first premolars. The 15-year-old patient also had a convex profile, maxillary dentoalveolar protrusion, and deficiency of space for the correct alignment of teeth. Therefore, treatment consisted of fixed appliance therapy, cervical headgear, extraction of the supernumeraries and the mandibular and maxillary first premolars, and mesiodistal reduction of the maxillary incisors to solve the arch perimeter discrepancy as much as possible with interproximal stripping. This method of treatment significantly improved the patient's facial and dental esthetics and provided a good functional occlusion, despite the absence of a mandibular incisor, which generally impairs achieving adequate incisal guidance.
Han, Ting; Ma, Yue; Yang, Lin; Chen, Xinyu; Zhang, Xin; Wang, Yan
The purpose of this study was to investigate the root canal configuration of the mandibular anterior teeth using cone-beam computed tomographic (CBCT) imaging in a Chinese subpopulation. A total of 3,871 CBCT images of mandibular anterior teeth were collected from 648 patients who accepted CBCT projection as a preoperative assessment for implants or orthodontic treatment. The following items were recorded and evaluated: tooth position, root number, canal number, root canal type, the distance between the anatomic apex and the point at which the canal divided into 2 for mandibular anterior teeth with 2 root canals (excluding canines with 2 roots), and the distance between the 2 root canal orifices. The Fisher exact test was used to analyze the correlation between the number of root canals and tooth position. All of the incisors in this study had 1 root, and 1.32% of the canines had 2 roots. The prevalence of 2 root canals in the lateral incisors (354, 27.36%) was higher than that in the central incisors (202, 15.71%) (P < .05) and the canines (81, 6.27%) (P < .05). There is a high prevalence of 2 root canals in the mandibular anterior teeth of the studied Chinese subpopulation. This study provides detailed information about the root canal morphology of mandibular anterior teeth in a Chinese subpopulation. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Joss, C U; Triaca, A; Antonini, M; Kiliaridis, S; Kuijpers-Jagtman, A M
33 patients (27 females; 6 males) were retrospectively analysed for skeletal and dental relapse before distraction osteogenesis (DOG) of the mandibular anterior alveolar process at T1 (17.0 days), after DOG at T2 (mean 6.5 days), at T3 (mean 24.4 days), and at T4 (mean 2.0 years). Lateral cephalograms were traced by hand, digitized, superimposed, and evaluated. Skeletal correction (T3-T1) was mainly achieved through the distraction of the anterior alveolar segment in a rotational manner where the incisors were more proclined. The horizontal backward relapse (T4-T3) measured -0.8mm or 19.0% at point B (p<0.001) and -1.6mm or 25.0% at incision inferior (p<0.001). Age, gender, amount and type (rotational versus translational) of advancement were not correlated with the amount of relapse. High angle patients (NL/ML'; p<0.01) and patients with large gonial angle (p<0.05) showed significantly smaller relapse rates at point B. Overcorrection of the overjet achieved by the distraction was seen in a third of the patients and could be a reason for relapse. Considering the amount of skeletal relapse the DOG could be an alternative to bilateral sagittal split osteotomy for mandibular advancement in selected cases.
Viswanath, Divya; Shetty, Sandeep; Mascarenhas, Rohan; Husain, Akhter
A 20-year-old woman presented with a labially displaced mandibular right central incisor with severe attrition. Her maxillary dentition was well-aligned, and she had a straight profile. The respective central incisor was extracted. Subsequently, all teeth were aligned and the extraction space was closed with 2D lingual brackets. The result was esthetically pleasing.
Ruellas, Antonio Carlos de Oliveira; Yatabe, Marilia Sayako; Souki, Bernardo Quiroga; Benavides, Erika; Nguyen, Tung; Luiz, Ronir Raggio; Franchi, Lorenzo; Cevidanes, Lucia Helena Soares
Introduction The aim was to evaluate three regions of reference (Björk, Modified Björk and mandibular Body) for mandibular registration testing them in a patients’ CBCT sample. Methods Mandibular 3D volumetric label maps were built from CBCTs taken before (T1) and after treatment (T2) in a sample of 16 growing subjects and labeled with eight landmarks. Registrations of T1 and T2 images relative to the different regions of reference were performed, and 3D surface models were generated. Seven mandibular dimensions were measured separately for each time-point (T1 and T2) in relation to a stable reference structure (lingual cortical of symphysis), and the T2-T1 differences were calculated. These differences were compared to differences measured between the superimposed T2 (generated from different regions of reference: Björk, Modified Björk and Mandibular Body) over T1 surface models. ICC and the Bland-Altman method tested the agreement of the changes obtained by nonsuperimposition measurements from the patients’ sample, and changes between the overlapped surfaces after registration using the different regions of reference. Results The Björk region of reference (or mask) did work properly only in 2 of 16 patients. Evaluating the two other masks (Modified Björk and Mandibular body) on patients’ scans registration, the concordance and agreement of the changes obtained from superimpositions (registered T2 over T1) compared to results obtained from non superimposed T1 and T2 separately, indicated that Mandibular Body mask displayed more consistent results. Conclusions The mandibular body mask (mandible without teeth, alveolar bone, rami and condyles) is a reliable reference for 3D regional registration. PMID:27336366
Kayaoglu, Guven; Peker, Ilkay; Gumusok, Mustafa; Sarikir, Cigdem; Kayadugun, Aylin; Ucok, Ozlem
The aims of this study were to evaluate the number of roots/root canals in the mandibular anterior teeth of a Turkish population, to assess the relationship between gender or age and the frequency of two canals in a single root, and to determine the symmetry in root/root canal numbers between contralateral sides among patients. Cone-beam computed tomography images (n = 1128; 6253 teeth) taken at the Department of Dentomaxillofacial Radiology of the Faculty of Dentistry of Gazi University were examined by three observers and a supervisor, all of whom were blinded to patient gender and age. Axial, sagittal, and cross-sectional slices with a thickness of 1 mm were used. Numbers of roots and canals for each type of tooth were recorded. Most teeth had a single root and single root canal. Roots with two canals were more frequent in the incisors (14.9%, 17.2%, and 6.1% of the central incisors, lateral incisors, and canines, respectively). Teeth with two roots were more frequent in the canines (3.1% vs. 0% or 0.1%). Females more often had canines with double root canals (p < 0.001). When at least one tooth had two root canals, bilateral symmetry between contralateral teeth was found in 45.0%, 29.0%, and 28.0% of cases for central incisors, lateral incisors, and canines, respectively. Patients older than 56 years had fewer teeth with double root canals (p ≤ 0.001). A small proportion of the mandibular anterior teeth had two roots or root canals. Double root canals were mostly unilateral. Age and gender were associated with the number of root canals.
Naganahalli, Manjunath; Honnappa, Adarsh; Chaitanya, Nallan Csk
Developmental anomalies affecting the number of teeth are occasionally encountered clinically. The incidence of supernumerary teeth is approximately 1-3%. Among these are the maxillary anterior teeth, the maxillary molars, and the maxillo-mandubular premolars, in terms of descending order of occurrence. Supernumeraries occur rarely in the mandibular anterior teeth region. They may be either supplemental or rudimentary. We are reporting case of a supplemental type of supernumerary tooth in the mandibular anterior region and steps which were followed to distinguish supernumerary tooth from the normal series.
Naganahalli, Manjunath; Honnappa, Adarsh; Chaitanya, Nallan CSK
Developmental anomalies affecting the number of teeth are occasionally encountered clinically. The incidence of supernumerary teeth is approximately 1–3%. Among these are the maxillary anterior teeth, the maxillary molars, and the maxillo-mandubular premolars, in terms of descending order of occurrence. Supernumeraries occur rarely in the mandibular anterior teeth region. They may be either supplemental or rudimentary. We are reporting case of a supplemental type of supernumerary tooth in the mandibular anterior region and steps which were followed to distinguish supernumerary tooth from the normal series. PMID:24551732
Antoszewska-Smith, J.; Bohater, M.; Kawala, M.
The attempt of this article was to assess reliability of Little's Irregularity Index (LII) as for stability of the treatment outcomes in adults with crowded mandibular incisors. LII was measured on a digital cast prior to an orthodontic treatment (T1) of the 302 patients thus allowing us to establish the treatment plan, which called for (a) expansion (group 1), interproximal stripping (group 2), or extraction of one of the mandibular incisors. LII was measured after debonding (T2) and a year after retention (T3). Treatment resulted in significant reduction of LII values after treatment, in T1-T2 period in all groups. As for T2-T3 period it brought significant but clinically irrelevant relapse that occurred in groups 1 and 2; group 3 presented with insignificant improvement of occlusion. Conclusively, 30 years after introducing LII it has been a reliable parameter that allows selection of optimal treatment methods, provided that the appropriate ranges of values displaying dentoalveolar discrepancy are obeyed, namely, (1) up to 3 mm: expansion, (2) from 3 to 5 mm: interproximal enamel reduction, and (3) above 5 mm: extraction. PMID:28265286
da Silva, Emmanuel João Nogueira Leal; de Castro, Raquel Werczler Queiroz; Nejaim, Yuri; Silva, Amaro Ilídio Vespasiano; Haiter-Neto, Francisco; Silberman, Aian; Cohenca, Nestor
Several studies demonstrate variability of root canal morphology of anterior teeth. This in-vivo study was designed to analyze and characterize root canal morphology of maxillary and mandibular anterior teeth using three-dimensional imaging. Patients who required CBCT radiographic examinations as part of their routine examination, diagnosis, and treatment planning were enrolled on the study. A total of 1,200 healthy, untreated, fully developed maxillary and mandibular incisors and canines were included. The following observations were recorded: (i) number of roots and their morphology; (ii) number of canals per root; and (iii) primary variations in the morphology of the root canal systems. Root canal morphology of maxillary teeth was consistent with a single canal extending from the pulp chamber to the apex in 98% of the cases. In contrast, in mandibular central and lateral incisors, the presence of a single canal represented 64.5% and 60.5% respectively. The second most common morphology was the presence of one canal leaving the pulp chamber, which divided into two within the root, and then merged to exit as one canal in 18% and 25.5% respectively. The presence of one canal leaving the pulp chamber and dividing short of the apex into two separate and distinct canals with separate apical foramina (variant 5) was recorded in 14.5% and 12% respectively. There was a low incidence of anatomical variation in maxillary anterior teeth. In contrast, mandibular anterior teeth presented with a high prevalence of two canals, especially central and lateral incisors. The reported data may help clinicians understand the variations in root canal morphology of anterior teeth in order to overcome problems associated with shaping and cleaning procedures.
Bayram, Mehmet; Özer, Mete
Many approaches for crowded mandibular anterior teeth are currently employed: distal movement of posterior teeth, lateral movement of canines, labial movement of incisors, interproximal enamel reduction, removal of premolars, removal of one or two incisors, and various combinations of the above. Selecting the best treatment is often difficult, and all guidelines do not apply to every case. Treatment by extraction of one single mandibular incisor is not popular in the orthodontic profession despite the apparent advantages of the extraction in the region of crowding. A case report is presented one mandibular incisor extraction treatment of a 16 year-old female with a Class I malocclusion that shows a significant mandibular arch length deficiency and mandibular tooth-size excess. In this case, the degree of mandibular anterior dental crowding, existing mandibular tooth-size excess, and the dental midline discrepancy were indicated the extraction of one mandibular incisor. PMID:19212499
Joss, C U; Triaca, A; Antonini, M; Kiliaridis, S; Kuijpers-Jagtman, A M
Soft tissue changes were analysed retrospectively in 17 patients following distraction osteogenesis (DO) of the mandibular anterior alveolar process. Lateral cephalograms were traced by hand, digitized, superimposed, and evaluated at T1 (17.0 days), after DO at T2 (mean 6.5 days), at T3 (mean 24.4 days), at T4 (mean 2.0 years), and at T5 (mean 5.5 years). Statistical analysis was carried out using Kolmogorov-Smirnov test, paired t-test, Pearson's correlation coefficient, and linear backward regression analysis. 5.5 years postoperatively, the net effect for the soft tissue at point B' was 88% of the advancement at point B while the lower lip (labrale inferior) followed the advancement of incision inferior to 24%. Increased preoperative age was correlated (p<0.05) with more horizontal backward movement (T5-T3) for labrale inferior and pogonion'. Higher NL/ML' angles were significantly correlated (p<0.05) to smaller horizontal soft tissue change at labrale inferior (T5-T3). The amount of advancement at point B was significantly correlated with an upward movement (T5-T3) of labrale inferior (p<0.01) and stomion inferior (p<0.05). It can be concluded that further change in soft tissues occurred between 2.0 and 5.5 years postoperatively. The physiological process of ageing and loss of soft tissue elasticity should be considered as possible reasons.
Resection of the anterior arch of the mandible leads to tongue fall and postoperative stridor because of the detachment of tongue musculature from the mandible. In this article, a simple method of tongue suspension is described which would prevent such complications and the need for tracheostomy. This study was carried out on patients with oral cancer requiring resection of the anterior arch of the mandible as a part of the surgical resection at a tertiary centre. This study was performed on 32 patients with oral cancer requiring resection of the anterior arch of the mandible as a part of the surgical resection. Following an appropriate resection of the oral cancer (including the anterior mandibular arch) and neck dissection, a silk suture is used to loop the tongue musculature on either side to the intermediate tendon of the digastric muscle. This technique of tongue suspension was used in 32 patients who required resection of the anterior mandibular arch for oral cancer. Prophylactic tracheostomy was not performed. One patient developed stridor at extubation and required temporary tracheostomy. All other patients could be successfully extubated within 12 h of surgery and none experienced postoperative stridor or sleep apnea. One other patient required temporary tracheostomy for pulmonary toilet as he developed aspiration pneumonitis related to nasogastric feed. This simple method of tongue suspension to the digastric tendon prevents postoperative tongue fall and obviates the need for tracheostomy in most instances.
Varghese, Vinny Sara; George, John V.; Mathew, Sylvia; Nagaraja, Shruthi; Indiresha, H. N.; Madhu, K. S.
Background and Objectives: The aim of the study was to determine the effect of two access cavity designs on the peri-cervical dentin thickness before and after instrumentation using cone beam computed tomography (CBCT). Materials and Methods: Sixty mandibular anterior teeth were divided into two groups of thirty teeth each: Group I: conventional access cavity preparation, where access was prepared just above the cingulum and Group II: incisal access cavity preparation, where access was prepared in proximity to the incisal edge. CBCT scans were taken preoperatively, following access cavity preparation and post instrumentation. 200 μm thick slices were obtained 4mm apical and coronal to the cemento-enamel junction. The peri-cervical dentin thickness was calculated on the facial, lingual, mesial, and distal for all the three obtained scans. Results: The analysis showed that access cavity preparation and instrumentation resulted in a significant loss of tooth structure in Group I on all surfaces, but in Group II, there was a significant loss of tooth structure only in the mesial, lingual, and distal surfaces (P < 0.05). Conclusion: Incisal access cavity preparation resulted in lesser loss of dentin in the peri-cervical region. PMID:27656065
de Souza, Lílian Azevedo; Souza Picorelli Assis, Neuza Maria; Ribeiro, Rosangela Almeida; Pires Carvalho, Antônio Carlos; Devito, Karina Lopes
The aim of this study has been to evaluate and correlate the anatomical features of the posterior mandibular region (submandibular fossa depth, bone height and thickness, and mandibular canal corticalization) to improve accident prevention and allow safe planning in implantology. Four parasagittal sections of cone-beam computed tomography (CBCT) from 100 patients were bilaterally analyzed. Linear measurements of the submandibular fossa depth, bone height and thickness were performed. The submandibular fossa was also classified into non-influential undercuts and influential undercuts for implant placement. Mandibular canal corticalization was also evaluated and classified according to the visualization. Data on patient age and gender were also collected. Forty-one scans (41%) were from male patients, and 59 (59%) were from female patients. Patient age ranged between 18 and 84 years, with an average age of 51.37 years. The submandibular fossa depth and implant bone thickness had a significant effect on the variability of the sample (46.1% and 22.3%, respectively). The submandibular fossa depth was quite variable, and the highest values were observed in the posterior regions. In 18.27% of the cases, the presence of the fossa directly influenced implant placement, considering a bone height of 10mm (standard implant). A significant correlation was observed between fossa depth and bone thickness. Thus, greater attention should be paid to thick ridges; although thick ridges are favorable, they may be associated with deeper submandibular fossae. The mandibular canal was the most influential anatomical structure in the premolar region due to the reduced bone height in this region and the greater difficulty in viewing the canal, and the submandibular fossa was the most influential structure in the molar region due to lower bone height leading up to the fossa and the greater fossa depth in this region. Therefore, CBCT is an important tool for assessing the mandibular region
Okamoto, Y.; Takasugi, Y.; Moriya, K.; Furuya, H.
We studied the spread of local anesthetic solution in the inferior alveolar nerve block by the injection of local anesthetic solution into the pterygomandibular space anterior to the mandibular foramen (anterior technique). Seventeen volunteers were injected with 1.8 mL of a mixture containing lidocaine and contrast medium utilizing the anterior technique. The course of spread was traced by fluoroscopy in the sagittal plane, and the distribution area was evaluated by lateral cephalograms and horizontal computed tomography. The results indicate that the contrast medium mixture spreads rapidly in the pterygomandibular space to the inferior alveolar nerve in the subjects who exhibited inferior alveolar nerve block effect. We concluded that the anesthetic effect due to the anterior technique was produced by the rapid distribution of anesthetic solution in the pterygomandibular space toward the mandibular foramen, and individual differences in the time of onset of analgesia may be due to differences in the histologic perineural tissues. Images Figure 1 Figure 2 Figure 3 PMID:11432178
Nirmala, S. V. S. G.; Sandeep, C.; Nuvvula, Sivakumar; Mallineni, Sreekanth Kumar
Dental anomalies of tooth number in development of the permanent dentition are quite common than the primary dentition, however, the combined occurrence of hypodontia and hyperdontia is a rare phenomenon, especially in the same dental arch. The purpose of this report is to describe a case of concomitant hypo-hyperdontia (CHH) in three patients (one girl and two boys) with missing mandibular central incisor and an erupted mandibular mesiodens. Three rare cases of mandibular CHH were observed during routine examination, where the two anomalies manifested in the anterior region of the mandible. Furthermore, these are the only cases exhibited taurodontism in association with mandibular CHH. PMID:24778987
Nirmala, S V S G; Sandeep, C; Nuvvula, Sivakumar; Mallineni, Sreekanth Kumar
Dental anomalies of tooth number in development of the permanent dentition are quite common than the primary dentition, however, the combined occurrence of hypodontia and hyperdontia is a rare phenomenon, especially in the same dental arch. The purpose of this report is to describe a case of concomitant hypo-hyperdontia (CHH) in three patients (one girl and two boys) with missing mandibular central incisor and an erupted mandibular mesiodens. Three rare cases of mandibular CHH were observed during routine examination, where the two anomalies manifested in the anterior region of the mandible. Furthermore, these are the only cases exhibited taurodontism in association with mandibular CHH.
MacKenzie, BreAnne; Wolff, Ryan; Lowe, Nick; Billington, Charles J.; Peterson, Ashley; Schmidt, Brian; Graf, Daniel; Mina, Mina; Gopalakrishnan, Rajaram; Petryk, Anna
SUMMARY The mandibular arch (BA1) is critical for craniofacial development. The distal region of BA1, which gives rise to most of the mandible, is dependent upon an optimal level of Bone morphogenetic protein (BMP) signaling. BMP activity is modulated in the extracellular space by BMP-binding proteins such as Twisted gastrulation (TWSG1). Twsg1−/− mice have a spectrum of craniofacial phenotypes, including mandibular defects that range from micrognathia to agnathia. At E9.5, the distal region of the mutant BA1 was prematurely and variably fused with loss of distal markers eHand and Msx1. Expression of proximal markers Fgf8 and Barx1 was expanded across the fused BA1. The expression of Bmp4 and Msx2 was preserved in the distal region, but shifted ventrally. While wild type embryos showed a gradient of BMP signaling with higher activity in the distal region of BA1, this gradient was disrupted and shifted ventrally in the mutants. Thus, loss of TWSG1 results in disruption of the BMP4 gradient at the level of signaling activity as well as mRNA expression. Altered distribution of BMP signaling leads to a shift in gene expression and increase in apoptosis. The extent of apoptosis may account for the variable degree of mandibular defects in Twsg1 mutants. PMID:19389368
Pithon, Matheus Melo
This clinical case report presents the nonsurgical orthodontic treatment of a patient with skeletal Class II malocclusion, posterior crossbite, anterior open bite, accentuated dental discrepancies in both arches, and an odontoma. The proposed treatment involved maxillary expansion, extraction of atypical maxillary lateral incisors and mandibular first molars, and intrusion of maxillary teeth with the aid of mini-implants. The results obtained with these procedures included good tooth alignment, normal overbite and overjet, removal of the odontoma, and a harmonious smile. In complex cases, an accurate diagnosis is the key to a favorable outcome. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Joss, C U; Triaca, A; Antonini, M; Kiliaridis, S; Kuijpers-Jagtman, A M
17 patients (14 female; 3 male) were analysed retrospectively for skeletal and dental relapse before distraction osteogenesis (DO) of the mandibular anterior alveolar process at T1 (17.0 days), after DO at T2 (mean 6.5 days), at T3 (mean 24.4 days), at T4 (mean 2.0 years), and at T5 (mean 5.5 years). Lateral cephalograms were traced by hand, digitized, superimposed, and evaluated. Skeletal correction (T5-T1) was mainly achieved through the distraction of the anterior alveolar segment in a rotational manner where the incisors were more proclined. The horizontal backward relapse (T5-T3) measured -0.3mm or 8.3% at point B (non-significant) and -1.8mm or 29.0% at incision inferior (p<0.01). Age, gender, amount and type (rotational vs. translational) of advancement were not correlated with the amount of relapse. High angle patients (NL/ML'; p<0.01) showed significant smaller relapse rates at point B. Overcorrection of the overjet achieved by the distraction could be a reason for dental relapse. Considering the amount of long-term skeletal relapse the DO could be an alternative to bilateral sagittal split osteotomy for mandibular advancement in selected cases.
de Carvalho Leite Leal Nunes, Carla Maria; de Almeida Lopes, Maria Cândida
ABSTRACT Objectives This study evaluated the relationship of the lingual nerve with the adjacent anatomical structures of the mandibular third molar region, influencing the dentist to be aware of the variability of these relationships. Material and Methods Samples of 24 human corpse half-heads were selected and divided according with the presence or absence of the mandibular third molars. The lingual nerve (LN) was explored, showing its run from the oblique line until its crossing with the submandibular gland duct. The measurements along the LN and the adjacent anatomical structures were taken at the retromolar, molar and sublingual region with the use of a digital caliper. Results The distance from the LN and the third molar socket, which represents the horizontal distance of the lingual plate to the nerve, on average, was 4.4 mm (SD 2.4 mm). The distance from the LN and the lingual alveolar rim, which represents the vertical relationship between the nerve and the lingual alveolar rim of the third molar socket, on average, was 16.8 mm (SD 5.7 mm). The LN has a varied topography that leaves it very vulnerable during any procedure executed in this region. Conclusions Unless adequate protection of the lingual nerve is acquired by following an adequate surgical technique, the lingual nerve will always be vulnerable to damage during surgical intervention or manipulation in this region. PMID:24478912
Kwon, H K; Owen, D G; Davidson, W M
A case of several developing supernumerary teeth is reported. A seven-year-old African-American boy presented with retained primary maxillary central incisors, two impacted mesiodens, and unerupted permanent maxillary central incisors. A dentigerous cyst was removed at the time of surgical removal of the mesiodens. Approximately fourteen months post-extraction, a new panoramic radiograph showed the presence of six previously unidentified developing and unerupted supernumerary teeth, one on each of the maxillary cuspid areas and two on the mandibular premolar regions bilaterally. Practitioners should be aware that supernumerary teeth may develop late. Thus, periodic reevaluation with appropriate radiographs is indicated, especially in patients who have presented with supernumerary teeth.
Joseph, Shiny; Priya, Lakshmi; Gopal, Dinesh; Devachen, Mary; Narayan, Ajay; Afnan, Muhammed
Ameloblastic fibrodentinoma is a rare benign mixed odontogenic neoplasm usually occurring in the first two decades of life. It is more common in males and the most common site of occurrence is in the mandibular premolar molar area. This report presents a case of ameloblastic fibrodentinoma in a 12-year-old boy in the maxillary anterior region, a less common site for the occurrence of ameloblastic fibrodentinoma. A 12-year-old boy presented with a midline diastema in 11 and 21 region and a swelling in the palatal aspect of 11 and 12. Intraoral periapical radiograph showed the presence of rarefaction of bone on the mesial aspect of the cervical and middle third of the root of 11. Excision biopsy was done. The specimen was processed and stained with hematoxylin and eosin. Microscopic examination showed islands, chords and strands of odontogenic epithelium in a primitive ectomesenchyme resembling dental papilla. The odontogenic epithelium exhibited peripheral ameloblast-like and central stellate reticulum-like cells. The presence of dentinoid material was seen adjacent to the odontogenic epithelium in some foci. The lesion was diagnosed as ameloblastic fibrodentinoma.
Joseph, Shiny; Priya, Lakshmi; Gopal, Dinesh; Devachen, Mary; Narayan, Ajay; Afnan, Muhammed
Ameloblastic fibrodentinoma is a rare benign mixed odontogenic neoplasm usually occurring in the first two decades of life. It is more common in males and the most common site of occurrence is in the mandibular premolar molar area. This report presents a case of ameloblastic fibrodentinoma in a 12-year-old boy in the maxillary anterior region, a less common site for the occurrence of ameloblastic fibrodentinoma. A 12-year-old boy presented with a midline diastema in 11 and 21 region and a swelling in the palatal aspect of 11 and 12. Intraoral periapical radiograph showed the presence of rarefaction of bone on the mesial aspect of the cervical and middle third of the root of 11. Excision biopsy was done. The specimen was processed and stained with hematoxylin and eosin. Microscopic examination showed islands, chords and strands of odontogenic epithelium in a primitive ectomesenchyme resembling dental papilla. The odontogenic epithelium exhibited peripheral ameloblast-like and central stellate reticulum-like cells. The presence of dentinoid material was seen adjacent to the odontogenic epithelium in some foci. The lesion was diagnosed as ameloblastic fibrodentinoma. PMID:25709845
Shahid, Fazal; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli
Objective: To investigate the maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width (intercanine, interpremolar, and intermolar) groups. Materials and Methods: The calculated sample size was 128 subjects. The crown width/height, arch length, arch perimeter, and arch width of the maxilla and mandible were obtained via digital calliper (Mitutoyo, Japan). A total of 4325 variables were measured. The sex differences in the crown width and height were evaluated. Analysis of variance was applied to evaluate the differences between arch length, arch perimeter, and arch width groups. Results: Males had significantly larger mean values for crown width and height than females (P ≤ 0.05) for maxillary and mandibular arches, both. There were no significant differences observed for the crown width/height ratio in various arch length, arch perimeter, and arch width (intercanine, interpremolar, and intermolar) groups (P ≤ 0.05) in maxilla and mandible, both. Conclusions: Our results indicate sexual disparities in the crown width and height. Crown width and height has no significant relation to various arch length, arch perimeter, and arch width groups of maxilla and mandible. Thus, it may be helpful for orthodontic and prosthodontic case investigations and comprehensive management. PMID:26929686
Brown, Elizabeth C.; Cheng, Shaokoon; McKenzie, David K.; Butler, Jane E.; Gandevia, Simon C.; Bilston, Lynne E.
Study Objectives: To characterize tongue and lateral upper airway movement and to image tongue deformation during mandibular advancement. Design: Dynamic imaging study of a wide range of apnea hypopnea index (AHI), body mass index (BMI) subjects. Setting: Not-for-profit research institute. Participants: 30 subjects (aged 31-69 y, AHI 0-75 events/h, BMI 17-39 kg/m2). Interventions: Subjects were imaged using dynamic tagged magnetic resonance imaging during mandibular advancement. Tissue displacements were quantified with the harmonic phase technique. Measurements and Results: Mean mandibular advancement was 5.6 ± 1.8 mm (mean ± standard deviation). This produced movement through a connection from the ramus of the mandible to the pharyngeal lateral walls in all subjects. In the sagittal plane, 3 patterns of posterior tongue deformation were seen with mandibular advancement—(A) en bloc anterior movement, (B) anterior movement of the oropharyngeal region, and (C) minimal anterior movement. Subjects with lower AHI were more likely to have en bloc movement (P = 0.04) than minimal movement. Antero-posterior elongation of the tongue increased with AHI (R = 0.461, P = 0.01). Mean anterior displacements of the posterior nasopharyngeal and oropharyngeal regions of the tongue were 20% ± 13% and 31% ± 17% of mandibular advancement. The posterior tongue compressed 1.1 ± 2.2 mm supero-inferiorly. Conclusions: Mandibular advancement has two mechanisms of action which increase airway size. In subjects with low AHI, the entire tongue moves forward. Mandibular advancement also produces lateral airway expansion via a direct connection between the lateral walls and the ramus of the mandible. Citation: Brown EC; Cheng S; McKenzie DK; Butler JE; Gandevia SC; Bilston LE. Tongue and lateral upper airway movement with mandibular advancement. SLEEP 2013;36(3):397-404. PMID:23450677
Marya, Charu Mohan; Sharma, Gaurav; Parashar, Vijay P; Dahiya, Vandana; Gupta, Anil
Concomitant hypo-hyperdontia is a rare mixed numeric anomalous condition. The presence of this condition in the same area of dental arch and specifically in the mandibular anterior region is reported very infrequently. This case report presents a case of 20 years old male with congenitally missing permanent mandibular central incisors in conjunction with a mandibular midline supernumerary tooth. Only 3 cases have been documented in English literature till date. The article focuses on the review of mandibular mesiodens and the clarity regarding the usage of the terminology "mesiodens".
Koerich, L; Burns, D; Weissheimer, A; Claus, J D P
This study aimed to validate a novel method for fast regional superimposition of cone beam computed tomography (CBCT) scans. The method can be used with smaller field of view scans, thereby allowing for a lower radiation dose. This retrospective study used two dry skulls and secondary data from 15 patients who had more than one scan taken using the same machine. Two observers tested two types of regional voxel-based superimposition: maxillary and mandibular. The registration took 10-15s. Three-dimensional surface models of the maxillas and mandibles were generated via standardized threshold segmentation, and the accuracy and reproducibility of the superimpositions were assessed using the iterative closest point technique to measure the root mean square (RMS) distance between the images. Five areas were measured and a RMS≤0.25 was considered successful. Descriptive statistics and the intra-class correlation coefficient (ICC) were used to compare the intra-observer measurement reproducibility. The ICC was ≥0.980 for all of the variables and the highest RMS found was 0.241. The inter-observer reproducibility was assessed case by case and was perfect (RMS 0) for 68% (23 out of 34) of the superimpositions done and not clinically significant (RMS≤0.25) for the other 32%. The method is fast, accurate, and reproducible and is an alternative to cranial base superimposition.
Kilinç, Yeliz; Erkmen, Erkan; Kurt, Ahmet
In this study, the biomechanical behavior of different fixation methods used to fix the mandibular anterior segment following various amounts of superior repositioning was evaluated by using Finite Element Analysis (FEA). The three-dimensional finite element models representing 3 and 5 mm superior repositioning were generated. The gap in between segments was assumed to be filled by block bone allograft and resignated to be in perfect contact with the mandible and segmented bone. Six different finite element models with 2 distinct mobilization rate including 3 different fixation configurations, double right L (DRL), double left L (DLL), or double I (DI) miniplates with monocortical screws, correspondingly were created. A comparative evaluation has been made under vertical, horizontal and oblique loads. The von Mises and principal maximum stress (Pmax) values were calculated by finite element solver programme. The first part of our ongoing Finite Element Analysis research has been addressed to the mechanical behavior of the same fixation configurations in nongrafted models. In comparison with the findings of the first part of the study, it was concluded that bone graft offers superior mechanical stability without any limitation of mobilization and less stress on the fixative appliances as well as in the bone.
Holton, Nathan E; Nicholas, Christina L; Marshall, Steve D; Franciscus, Robert G; Southard, Thomas E
A thorough understanding of influence of maxillary growth on patterns of mandibular rotation during development is important with regard to the treatment of skeletal discrepancies. In the present study, we examined whether experimentally altered maxillary position has a significant influence on patterns of mandibular rotation in a pig model. Maxillary growth was altered in a sample of n=10 domestic pigs via surgical fixation of the circummaxillary sutures. We compared the experimental group to control and surgical sham samples and assessed the effects of altered maxillary growth on mandibular form using geometric morphometric techniques. We tested for significant differences in mandibular shape between our samples and examined axes of morphological variation. Additionally, we examined whether altered mandibular shape resulting from altered maxillary position was predictably associated with morphological changes to the condylar region. There was a statistically significant difference in mandibular shape between the experimental and control/sham groups. As a result of vertical displacement of the snout, mandibles in the experimental sample resulted in greater anterior rotation when compared to the control/sham pigs. Variation in rotation was correlated with morphological changes in the condyle including the shape of the articular surface and condylar orientation indicative of greater anterior mandibular rotation. Vertical displacement of the maxilla had a significant effect on mandibular shape by encouraging anterior mandibular rotation. This result has important implications for understanding the effects of altered mandibular posture on condylar remodeling the treatment of skeletal discrepancies such as the correction of hyperdivegent mandibular growth. Copyright © 2015 Elsevier Ltd. All rights reserved.
Singh, Rabindra P; Carter, Lachlan M; Whitfield, Paul H
We conducted a regional 2-stage prospective audit involving 5 different maxillofacial units in the Yorkshire region of the UK to evaluate the effectiveness of perioperative antimicrobial prophylaxis in the treatment of mandibular fractures. In the first stage (145 patients) we surveyed current practice concerning antimicrobial prophylaxis and found out the current infection rate after open reduction and internal fixation (ORIF) of mandibular fractures. In the second stage (157 patients) we implemented a common antimicrobial protocol in all units and recorded the infection rates using the new regimen. In the first stage a wide range of antimicrobial prophylaxis was used in different units. The agreed perioperative antimicrobial protocol in the second stage was to begin amoxicillin or clarithromycin and metronidazole intravenously on admission and include 2 postoperative doses. The infection rates were 10.3% and 8.9%, respectively, and the difference between the two groups was not significant (χ(2)=0.051, df=1, p=0.83). The infection rate in the Yorkshire region was similar to results from other centres. We recommend short perioperative antimicrobial prophylaxis with a maximum of 2 postoperative doses after ORIF of mandibular fractures. Copyright © 2012 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Kimoto, Katsuhiko; Ono, Yumie; Tachibana, Atsumichi; Hirano, Yoshiyuki; Otsuka, Takero; Ohno, Akinori; Yamaya, Katsuhiko; Obata, Takayuki; Onozuka, Minoru
We used functional magnetic resonance imaging (fMRI) to investigate the change in brain regional activity during gum chewing when edentulous subjects switched from mandibular complete dentures to implant-supported removable overdentures. Four edentulous patients (3 males and 1 female, aged 64 to 79 years) participated in the study. All subjects received a set of new maxillary and mandibular complete dentures (CD), followed by a maxillary complete denture and a new mandibular implant-supported removable overdentures (IOD). A 3-T fMRI scanner produced images of the regional brain activity for each subject that showed changes in the blood-oxygenation-level-dependent (BOLD) contrast in the axial orientation during gum-chewing with CD and IOD. Region-of-interest analysis showed that IOD treatment significantly suppressed chewing-induced brain activity in the prefrontal cortex. The chewing-induced brain activities in the primary sensorimotor cortex and cerebellum tended to decrease with IOD treatment, however they did not reach to significance level. There was no change in brain activity in the supplementary motor area, thalamus and insula between gum chewing with CD and IOD. Group comparison using statistical parametrical mapping further showed that, within the prefrontal cortex, the neural activity of the frontal pole significantly decreased during gum-chewing with IOD when compared to that with CD (P<0.05). Despite the limitation of a small sample size, these results suggest that the gum-chewing task in elderly edentulous patients resulted in differential neural activity in the frontal pole within the prefrontal cortex between the 2 prosthodontic therapies-mandibular CD and IOD. Copyright © 2010 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.
Darwish, Salwa M; Salama, Fouad S
Impaction of primary teeth is very rare especially in the maxillary anterior teeth. A tooth that fails to erupt into a normal functional position by the time it normally should, is considered impacted. The purpose of this article is to present a case of a 2 year and 4-month-old male with an impacted primary mandibular central incisors. Clinical examination did not reveal systemic diseases or trauma in the facial region. Clinical and radiographic examinations are described. Treatment consisted of a period of observation for 6 months and the extraction of the impacted primary mandibular central incisors. Eight months after the surgery, the permanent central incisors were erupted in the proper position.
Blanc, Frédéric; Noblet, Vincent; Philippi, Nathalie; Cretin, Benjamin; Foucher, Jack; Armspach, Jean-Paul; Rousseau, François
Objectives We investigated the neural basis of hallucinations Alzheimer's disease (AD) by applying voxel-based morphometry (VBM) to anatomical and functional data from the AD Neuroimaging Initiative. Methods AD patients with hallucinations, based on the Neuropsychiatric Inventory (NPI-Q) (AD-hallu group; n = 39), were compared to AD patients without hallucinations matched for age, sex, educational level, handedness and MMSE (AD-c group; n = 39). Focal brain volume on MRI was analyzed and compared between the two groups according to the VBM method. We also performed voxel-level correlations between brain volume and hallucinations intensity. A similar paradigm was used for the PET analysis. “Core regions” (i.e. regions identified in both MRI and PET analyses, simply done by retaining the clusters obtained from the two analyses that are overlapping) were then determined. Results Regions with relative atrophy in association with hallucinations were: anterior part of the right insula, left superior frontal gyrus and lingual gyri. Regions with relative hypometabolism in association with hallucinations were a large right ventral and dorsolateral prefrontal area. "Core region" in association with hallucinations was the right anterior part of the insula. Correlations between intensity of hallucinations and brain volume were found in the right anterior insula, precentral gyrus, superior temporal gyrus, and left precuneus. Correlations between intensity of hallucinations and brain hypometabolism were found in the left midcingulate gyrus. We checked the neuropathological status and we found that the 4 patients autopsied in the AD-hallu group had the mixed pathology AD and Dementia with Lewy bodies (DLB). Conclusion Neural basis of hallucinations in cognitive neurodegenerative diseases (AD or AD and DLB) include a right predominant anterior-posterior network, and the anterior insula as the core region. This study is coherent with the top-down/bottom-up hypotheses on
Sreeram, Roopa Rani. S.; Prasad, L Krishna; Chakravarthi, P Srinivas; Devi, Naga Neelima; Sreeram, Sanjay Krishna
Background and Aims Missing teeth lead to loss of structural balance, inefficient function, poor aesthetics and psychological effects on human beings, which needs restoration for normal contour, function and aesthetics. Several natural or synthetic substitutes are being used for replacement of missing tooth since centuries. Implants are the latest modality of replacement. So, the study was aimed to assess clinical success rate of Hi-Tec implant; which is economical and new in market. Results of the study will help clinician for appropriate implant selection. Materials and Methods The study included 10 patients from 19 to 31 years and needed restoration of missing mandibular first molar. Restoration had done using Hi Tec Single-tooth implants with metal-ceramic single crown prosthesis after three months of osseointegration. The implants were evaluated clinically (bleeding on probing, probing depth, implant mobility- periotest) and radiographically (marginal bone loss and peri-implant radiolucency) for six years. The observers were blinded for the duration of the study to prevent bias. Results All the patients had uneventful post-surgical healing. No bleeding on probing, Implant mobility, peri-implant radiolucency with minimal marginal bone loss and constant probing depths were observed well within the normal range during follow-up periods. Conclusion Two stage single-tooth Hi Tec implant restoration can be used as a successful treatment modality for replacing mandibular first molar in an economic way. However, these results were obtained after 6 years of follow up with a smaller sample size, so long term multi center studies with a larger sample size is recommended for the predictability of success rate conclusively. PMID:26436053
Tezuka, T; Sugiyama, T; Sakurai, K
The purpose of this study was to examine the influence that the anteroposterior mandibular displacement near the tapping point exerts on the myoelectric activity of masseter and temporal muscles at a specific occluding force and to clarify the possibility of judging the mandibular position by measuring the amount of myoelectric discharge. Eight dentulous subjects were selected for the study. Surface electrodes were placed over the anterior, middle and posterior regions of the masseter muscle and over the anterior, middle and posterior bundles of the temporal muscle. Independently of the measurement region, the changes in the masseter and temporal muscle myoelectric activity which accompanied the anteroposterior mandibular displacement, were low. Moreover, when the mandible was displaced anteroposteriorly, the total amount of the myoelectrical discharge from all the recorded places, as well as the amounts of myoelectrical discharge over the middle part of the masseter muscle and the anterior bundle of the temporal muscle reached their lowest values in those mandibular positions which included the tapping point in less than half of the subjects. Therefore, this study indicates that the possibility of judging anteroposterior mandibular displacement by masseter and temporal muscle electromyography is quite low.
Jin, Jiu-Zhen; Warner, Dennis R; Ding, Jixiang
Recent studies have shown that mouse palatal mesenchymal cells undergo regional specification along the anterior-posterior (A-P) axis defined by anterior Shox2 and Msx1 expression and posterior Meox2 expression. A-P regional specification of the medial edge epithelium, which is directly responsible for palate fusion, has long been proposed, but it has not yet been demonstrated due to the lack of regional specific markers. In this study, we have demonstrated that the palate medial edge epithelium is regionalized along the A-P axis, similar to that for the underlying mesenchyme. Mmp13, a medial edge epithelium specific marker, was uniformly expressed from anterior to posterior in wild-type mouse palatal shelves. Previous studies demonstrated that medial edge epithelium expression of Mmp13 was regulated by TGF-beta3. We have found that the changes in Mmp13 expression in TGF-beta3 knockouts varied along the A-P axis, and can be broken down into three distinct regions. These regions correlated with regional specification of the underlying medial edge mesenchymal cells and timing of palate fusion. Mouse palate medial edge epithelium along the A-P axis can be divided into different regions according to the differential response to the loss of TGF-beta3.
a PA cephalogram to appreciate skeletal change. Growth and mandibular transverse development is modified through the interplay of resorption and...the mandible develops lateral to Meckel’s cartilage in utero, it should prove relatively stable during growth and development . With CBCT, this...Temporomandibular Joint. J Oral Maxillofac Surg 2009. 67:2254-65 17. Haas A. Rapid expansion of the maxillary dental arch and nasal cavity by opening the
Li, Xiao Hong; Stark, Meg; Vance, Gillian M; Cao, Jian Ping; Wilson, R Alan
The esophagus of blood-feeding schistosomes has been largely neglected although its posterior portion was designated as a gland decades ago. However, we recently showed it plays a pivotal role in blood processing. It is clearly demarcated into anterior and posterior compartments, both surrounded by a mass of cell bodies. Feeding movies revealed that erythrocytes accumulate in the anterior compartment before entering the posterior, indicating that a distinct process is executed there. We therefore investigated ultrastructural aspects and possible functions of the anterior region. The heads of adult Schistosoma japonicum were detached and prepared for both transmission and scanning electron microscopy to define the detailed ultrastructure of the anterior esophagus. Cryosections of heads were also prepared for immunocytochemistry and confocal microscopy to define the pattern of intrinsic host antibody binding in the anterior esophageal lining. The anterior syncytial lining of the esophagus is highly extended by long, thin corrugations of cytoplasm projecting towards the lumen. Strikingly in the male worm, the tips of the corrugations are further expanded by numerous threads of cytoplasm, producing a spaghetti-like appearance in the central lumen. Flattened, pitted cytoplasmic plates are interspersed in the tangled mass of threads. Abundant, morphologically distinct light vesicles of varied size and contents are manufactured in the cell bodies, from where they traffic through cytoplasmic connections to the corrugations and out to the tips. Clusters of vesicles accumulate in expanded tips in males, together with occasional mitochondria whilst females have more mitochondria but fewer vesicles. The membranous contents of light vesicles are secreted mainly from the tips, but also from the sides of the corrugations. They coat the surfaces and then form organised self-adherent membrane figures when shed into the lumen. Host antibody binds strongly in a characteristic pattern
Parker, M G; Lehman, J A; Martin, D E
The use of the vertical subcondylar osteotomy for correction of uncomplicated mandibular prognathism is reviewed. Techniques for use in more complicated cases such as when a set back of greater than 10 mm is required are also described.
Bidra, Avinash S; Rungruanganunt, Patchanee
The clinical outcomes of anterior implant abutments are not well reported. Purpose of the Study To systematically review the existing literature to identify survival, mechanical, biological, and esthetic outcomes of anterior implant abutments. An electronic search was performed using PubMed/MEDLINE with specific search terms and predetermined criteria. After application of inclusion and exclusion criteria, the final list of articles was reviewed in-depth to meet the objectives of this review. Systematic application of inclusion and exclusion criteria resulted in identification of 27 studies that described outcomes of anterior implant abutments. Because of substantial heterogeneity of data, true survival, or cumulative survival of abutments could not be calculated. However, the mean failure of abutments was 1.15%, attributable to fractures restricted to ceramic abutments. Mechanical complications included abutment screw loosening, primarily restricted to external hex implants. Biological complications included fistulas and mucosal recession. Esthetic outcomes showed lesser gingival discoloration for zirconia abutments compared with metal abutments. Minimal anterior abutment fractures have been reported and are restricted to ceramic abutments. Studies using spectrophotometry showed lesser gingival discoloration with zirconia abutments, but there is no evidence for difference in patient's esthetic satisfaction between ceramic and metal abutments. For the anterior region, selection of an implant with internal connection and a customized metal abutment (titanium or cast metal) can have the least mechanical complications. Limited existing clinical data indicate reduced peri-implant mucosal discoloration from zirconia abutments, which may be preferable over metal abutments, in patients with thinner mucosal tissues or patients with high or gummy smiles. © 2013 Wiley Periodicals, Inc.
Lee, Paul; Kim, Yong-Il; Kim, Seong-Sik; Park, Soo-Byung; Son, Woo-Sung
The aim of this retrospective study was to evaluate bony remodelling in the anterior region of the maxilla after bimaxillary surgery for skeletal Class III deformities preoperatively, immediately postoperatively, and 6 months postoperatively. For accurate analysis, cone-beam computed tomographic (CT) images of 29 patients (12 men and 17 women; mean age 22 (range 19 to 44) years) were used. The nasopalatine canal, unaffected by the maxillary Le Fort I osteotomy, was used for the reference points (posterosuperior, midpoint, and posteroinferior). The changes in the distance from each of the points on the nasopalatine canal to the corresponding anterior border of the maxilla were measured and analysed at the 3 stages (p<0.05). Bony resorption was apparent during the postoperative period, and the mean resorption was -1.13 (1.53) mm at the posterosuperior level, -0.92 (0.83) mm at the midpoint, and -0.83 (0.88) mm at the posteroinferior level (p<0.01). These findings show that there had been resorptive remodelling postoperatively in the anterior maxillary region after bimaxillary surgery with superior maxillary movement, which suggests that the postoperative change in the position of point A is affected by operative movement as well as by postoperative relapse and bony remodelling. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Ansell, Emily B.; Rando, Kenneth; Tuit, Keri; Guarnaccia, Joseph; Sinha, Rajita
Background Cumulative adversity and stress are associated with risk of psychiatric disorders. While basic science studies show repeated and chronic stress effects on prefrontal and limbic neurons, human studies examining cumulative stress and effects on brain morphology are rare. Thus, we assessed whether cumulative adversity is associated with differences in gray matter volume, particularly in regions regulating emotion, self-control, and top-down processing in a community sample. Methods One hundred three healthy community participants, aged 18 to 48 and 68% male, completed interview assessment of cumulative adversity and a structural magnetic resonance imaging protocol. Whole-brain voxel-based-morphometry analysis was performed adjusting for age, gender, and total intracranial volume. Results Cumulative adversity was associated with smaller volume in medial prefrontal cortex (PFC), insular cortex, and subgenual anterior cingulate regions (familywise error corrected, p <.001). Recent stressful life events were associated with smaller volume in two clusters: the medial PFC and the right insula. Life trauma was associated with smaller volume in the medial PFC, anterior cingulate, and subgenual regions. The interaction of greater subjective chronic stress and greater cumulative life events was associated with smaller volume in the orbitofrontal cortex, insula, and anterior and subgenual cingulate regions. Conclusions Current results demonstrate that increasing cumulative exposure to adverse life events is associated with smaller gray matter volume in key prefrontal and limbic regions involved in stress, emotion and reward regulation, and impulse control. These differences found in community participants may serve to mediate vulnerability to depression, addiction, and other stress-related psychopathology. PMID:22218286
Yoshida, K; Kaji, R; Hamano, T; Kohara, N; Kimura, J; Shibasaki, H; Iizuka, T
Movement-related cortical potentials (MRCPs) are negative potentials over the scalp, which gradually increase prior to voluntary movements, and might be applied to elucidate the cortical efferent function of the mandibular movements. We compared the MRCPs accompanying various mandibular movements to study the motor control mechanism underlying these movements. Electroencephalograms (EEGs) were recorded from 11 electrodes placed over the scalp (F3, Fz, F4, T3, C3, Cz, C4, T4, P3, Pz, and P4), according to the International 10-20 System, and electromyograms (EMGs) were obtained from surface electrodes over the masseter muscle and the anterior belly of the digastric muscle. Ten healthy subjects were requested to make brisk and self-paced mandibular movements in 4 different directions (mouth-opening and -closing, and left and right lateral movements). We obtained MRCPs by averaging the EEG, using the visually determined EMG onset as a trigger signal. In all the movements, a slowly increasing, bilaterally widespread negativity starting 1.5 to 2.0 sec before the EMG onset (Bereitschaftspotential, or BP proper) was observed, with the maximum over the vertex region. The negative slope (NS') occurred about 300 to 700 msec before the EMG onset. The cortical maps of BP/NS' (BP and NS' combined), immediately prior to the mouth-opening and closing, showed a symmetrical distribution, whereas that for the lateral movements showed a tendency of predominance over the hemisphere ipsilateral to the direction of the movement. BP/NS' amplitudes at the onset of movement differed significantly or tended to do so between open, close, and lateral movements, suggesting that MRCP recordings may thus provide a means to explore the role of the cerebral cortex in the control of mandibular movements.
Firmino, João; Tinevez, Jean-Yves; Knust, Elisabeth
Maintenance of apico-basal polarity is essential for epithelial integrity and requires particular reinforcement during tissue morphogenesis, when cells are reorganised, undergo shape changes and remodel their junctions. It is well established that epithelial integrity during morphogenetic processes depends on the dynamic exchange of adherens junction components, but our knowledge on the dynamics of other proteins and their dynamics during these processes is still limited. The early Drosophila embryo is an ideal system to study membrane dynamics during morphogenesis. Here, morphogenetic activities differ along the anterior-posterior axis, with the extending germband showing a high degree of epithelial remodelling. We developed a Fluorescence Recovery After Photobleaching (FRAP) assay with a higher temporal resolution, which allowed the distinction between a fast and a slow component of recovery of membrane proteins during the germband extension stage. We show for the first time that the recovery kinetics of a general membrane marker, SpiderGFP, differs in the anterior and posterior parts of the embryo, which correlates well with the different morphogenetic activities of the respective embryonic regions. Interestingly, absence of crumbs, a polarity regulator essential for epithelial integrity in the Drosophila embryo, decreases the fast component of SpiderGFP and of the apical marker Stranded at Second-Venus specifically in the anterior region. We suggest that the defects in kinetics observed in crumbs mutant embryos are the first signs of tissue instability in this region, explaining the earlier breakdown of the head epidermis in comparison to that of the trunk, and that diffusion in the plasma membrane is affected by the absence of Crumbs.
Späti, Jakub; Hänggi, Jürgen; Doerig, Nadja; Ernst, Jutta; Sambataro, Fabio; Brakowski, Janis; Jäncke, Lutz; grosse Holtforth, Martin; Seifritz, Erich; Spinelli, Simona
Major depressive disorder (MDD) is associated with structural and functional alterations in the prefrontal cortex (PFC) and anterior cingulate cortex (ACC). Enhanced ACC activity at rest (measured using various imaging methodologies) is found in treatment-responsive patients and is hypothesized to bolster treatment response by fostering adaptive rumination. However, whether structural changes influence functional coupling between fronto-cingulate regions and ACC regional homogeneity (ReHo) and whether these functional changes are related to levels of adaptive rumination and treatment response is still unclear. Cortical thickness and ReHo maps were calculated in 21 unmedicated depressed patients and 35 healthy controls. Regions with reduced cortical thickness defined the seeds for the subsequent functional connectivity (FC) analyses. Patients completed the Response Style Questionnaire, which provided a measure of adaptive rumination associated with better response to psychotherapy. Compared with controls, depressed patients showed thinning of the right anterior PFC, increased prefrontal connectivity with the supragenual ACC (suACC), and higher ReHo in the suACC. The suACC clusters of increased ReHo and FC spatially overlapped. In depressed patients, suACC ReHo scores positively correlated with PFC thickness and with FC strength. Moreover, stronger fronto-cingulate connectivity was related to higher levels of adaptive rumination. Greater suACC ReHo and connectivity with the right anterior PFC seem to foster adaptive forms of self-referential processing associated with better response to psychotherapy, whereas prefrontal thinning impairs the ability of depressed patients to engage the suACC during a major depressive episode. Bolstering the function of the suACC may represent a potential target for treatment. PMID:25598428
Mitsugi, Masaharu; Alcalde, Rafael E.; Yano, Tomoyuki; Uemura, Noriko; Okazaki, Mutsumi
Backgrounds: The main problem with intraoral distraction of the mandible is the inability to achieve the three-dimensional mandibular correction as planned preoperatively. We developed a technique that allows spontaneous changes in the direction of mandibular elongation using an intraoral distractor. Methods: After mandibular osteotomy, the distractor is fixed to the distal segment of the mandible using a single bicortical screw, allowing anterior-posterior, vertical and limited lateromedial changes in the vector of distraction. Mandibular lengthening is performed while keeping the maxilla and mandible in class I occlusion with intermaxillary fixation. Results: As the distraction device is activated allowing mandibular elongation, the proximal segment, guided by the surrounding soft tissues, moves and rotates posterosuperiorly. Mandibular lengthening is continued until the condylar head reaches an adequate position in the mandibular fossa as confirmed clinically and radiographically. Conclusion Thirty-three patients with mandibular retrognathia received this treatment and good results were obtained. PMID:26301156
Quirynen, Marc; Mraiwa, Nuri; van Steenberghe, Daniel; Jacobs, Reinhilde
This study aimed to analyse variations in the mandibular interforaminal morphology in an attempt to identify potential risks or contraindications for surgery, especially implant installation, in this particular region. A total of 210 spiral computer tomography (CT) examinations of patients requiring endosseous implant installation in the lower jaw were re-evaluated to explore anatomical variations in bone morphology (shape and contour), and to measure parameters concerning height, width and inclination of the bone in the symphyseal atrea. All measurements were performed on the cross-sectional reformatted images mesial to the mental foramina. A lingual concavity (with a depth of 6 +/- 2.6 mm) was observed in 2.4% of the jaws, with a remaining bone height in that area ranging from 4.2 to 11.9 mm. A clearly lingual tilted/inclined morphology was seen in 28.1% of jaws with a mean angle of 67.6 +/- 6.5 degrees, but a relatively constant width (> 8.8 mm). The remaining jaws (69.5%) showed a slight broadening in the caudal direction. The morphologic parameters were influenced neither by age nor by gender. In conclusion, mandibles with a lingual concavity or a severe slope of the lingual cortex might confer increased risks of lingual perforations during trepanation surgery or graft harvesting as well as fenestrations during implant installation. The detection frequency of such variations within the lower jaw seems to advocate a profound dissection of the lingual site and, in the case of some special treatment strategies, additional cross-sectional radiography.
Krishnan, Unni; Al Maslamani, Manal; Moule, Alex J
We present two cases where the identities of mixed radiopaque radiolucent lesions in the lower incisor region were unclear, although the position of the lesions and positive pulp sensitivity tests were suggestive of periapical osseous dysplasia. In the first case, the lesion presented as a solitary round mixed radiopaque radiolucent periapical lesion, suggestive in some images as periapical osseous dysplasia. Cone beam CT (CBCT) provided clear images, which confirmed the diagnosis and, additionally, the images showed evidence of initial lesions associated with other anterior teeth and some destruction of the labial plate, not evident on the conventional radiographs. In the second case, radiopacities were identified within the lesion on conventional radiographs, but CBCT imaging also showed extensive and unexpected perforation of the lingual plate. Such destruction of cortical plates may be a feature of periapical osseous dysplasia, which is not visible in conventional radiography. PMID:25576510
This review provides an overview of comprehensive knowledge regarding the anatomy of the fasciae and fascial spaces of the maxillofacial and the anterior neck regions, principally from the standpoint of oral surgery, whose descriptions have long been puzzling and descriptively much too complex. The maxillofacial and the anterior neck regions are divided into four portions: the portions superficial and deep to the superficial layer of the deep cervical fascia (SfDCF) including its rostral extension to the face, the intermediate portion sandwiched by the splitting SfDCF, and the superficial portion peculiar to the face where the deep structures open on the body surface to form the oral cavity. Different fascial spaces are contained in each of the portions, although the spaces belonging to the portion of the same depth communicate freely with each other. The spaces of the superficial portions are adjacent to the oral cavity and constitute the starting point of deep infections from that cavity. The spaces of the intermediate portion lie around the mandible and occupy the position connecting the superficial and deep portions. Among these spaces, the submandibular and prestyloid spaces play an important role as relay stations conveying the infections into the deep portion. The spaces of the deep portion lie near the cervical viscera and communicate inferiorly with the superior mediastinum, among which the poststyloid space plays a role as a reception center of the infections and conveys the infections into the superior mediastinum particularly by way of the retrovisceral space and the carotid sheath.
Mutschler, Isabella; Reinbold, Céline; Wankerl, Johanna; Seifritz, Erich; Ball, Tonio
Empathy is key for healthy social functioning and individual differences in empathy have strong implications for manifold domains of social behavior. Empathy comprises of emotional and cognitive components and may also be closely linked to sensorimotor processes, which go along with the motivation and behavior to respond compassionately to another person's feelings. There is growing evidence for local plastic change in the structure of the healthy adult human brain in response to environmental demands or intrinsic factors. Here we have investigated changes in brain structure resulting from or predisposing to empathy. Structural MRI data of 101 healthy adult females was analyzed. Empathy in fictitious as well as real-life situations was assessed using a validated self-evaluation measure. Furthermore, empathy-related structural effects were also put into the context of a functional map of the anterior insular cortex (AIC) determined by activation likelihood estimate (ALE) meta-analysis of previous functional imaging studies. We found that gray matter (GM) density in the left dorsal AIC correlates with empathy and that this area overlaps with the domain general region (DGR) of the anterior insula that is situated in-between functional systems involved in emotion–cognition, pain, and motor tasks as determined by our meta-analysis. Thus, we propose that this insular region where we find structural differences depending on individual empathy may play a crucial role in modulating the efficiency of neural integration underlying emotional, cognitive, and sensorimotor information which is essential for global empathy. PMID:23675334
Mangano, Francesco Guido; Zecca, Piero Antonio; van Noort, Ric; Apresyan, Samvel; Iezzi, Giovanna; Piattelli, Adriano; Macchi, Aldo; Mangano, Carlo
This report documents the clinical, radiographic, and histologic outcome of a custom-made computer-aided-design/computer-aided-manufactured (CAD/CAM) scaffold used for the alveolar ridge augmentation of a severely atrophic anterior mandible. Computed tomographic (CT) images of an atrophic anterior mandible were acquired and modified into a 3-dimensional (3D) reconstruction model; this was transferred to a CAD program, where a custom-made scaffold was designed. CAM software generated a set of tool-paths for the manufacture of the scaffold on a computer-numerical-control milling machine into the exact shape of the 3D design. A custom-made scaffold was milled from a synthetic micromacroporous biphasic calcium phosphate (BCP) block. The scaffold closely matched the shape of the defect: this helped to reduce the time for the surgery and contributed to good healing. One year later, newly formed and well-integrated bone was clinically available, and two implants (AnyRidge, MegaGen, Gyeongbuk, South Korea) were placed. The histologic samples retrieved from the implant sites revealed compact mature bone undergoing remodelling, marrow spaces, and newly formed trabecular bone surrounded by residual BCP particles. This study demonstrates that custom-made scaffolds can be fabricated by combining CT scans and CAD/CAM techniques. Further studies on a larger sample of patients are needed to confirm these results.
Mangano, Francesco Guido; van Noort, Ric; Apresyan, Samvel; Piattelli, Adriano; Macchi, Aldo
This report documents the clinical, radiographic, and histologic outcome of a custom-made computer-aided-design/computer-aided-manufactured (CAD/CAM) scaffold used for the alveolar ridge augmentation of a severely atrophic anterior mandible. Computed tomographic (CT) images of an atrophic anterior mandible were acquired and modified into a 3-dimensional (3D) reconstruction model; this was transferred to a CAD program, where a custom-made scaffold was designed. CAM software generated a set of tool-paths for the manufacture of the scaffold on a computer-numerical-control milling machine into the exact shape of the 3D design. A custom-made scaffold was milled from a synthetic micromacroporous biphasic calcium phosphate (BCP) block. The scaffold closely matched the shape of the defect: this helped to reduce the time for the surgery and contributed to good healing. One year later, newly formed and well-integrated bone was clinically available, and two implants (AnyRidge, MegaGen, Gyeongbuk, South Korea) were placed. The histologic samples retrieved from the implant sites revealed compact mature bone undergoing remodelling, marrow spaces, and newly formed trabecular bone surrounded by residual BCP particles. This study demonstrates that custom-made scaffolds can be fabricated by combining CT scans and CAD/CAM techniques. Further studies on a larger sample of patients are needed to confirm these results. PMID:26064701
Zhao, Ying; Song, Luping; Ding, Junhua; Lin, Nan; Wang, Qiang; Du, Xiaoxia; Sun, Rong; Han, Zaizhu
The organizational principles of semantic memory in the human brain are still controversial. Although studies have shown that the semantic system contains hub regions that bind information from different sensorimotoric modalities to form concepts, it is unknown whether there are hub regions other than the anterior temporal lobe (ATL). Meanwhile, previous studies have rarely used network measurements to explore the hubs or correlated network indexes with semantic performance, although the most direct supportive evidence of hubs should come from the network perspective. To fill this gap, we correlated the brain-network index with semantic performance in 86 brain-damaged patients. We especially selected the nodal degree measure that reflects how well a node is connected in the network. The measure was calculated as the total number of connections of a given node with other nodes in the resting-state functional MRI network. Semantic ability was measured using the performance of both general and modality-specific (object form, color, motion, sound, manipulation, and function) semantic tasks. We found that the left ATL and the bilateral anterior cingulate cortex could be semantic hubs because the reduced nodal degree values of these regions could effectively predict the deficits in both general and modality-specific semantic performance. Moreover, the effects remained when the analyses were performed only in the patients who did not have lesions in these regions. The two hub regions might support semantic representations and executive control processes, respectively. These data provide empirical evidence for the distributed-plus-hub theory of semantic memory from the network perspective. Although the distributed-plus-hub organization of semantic memory has been proposed for several years, it remains unclear which hubs other than the anterior temporal lobe are included in the semantic system. Here, we identified such hubs from an innovative network perspective. The
Xie, Fang; Teng, Li; Jin, Xiaolei; Zheng, Jinlong; Xu, Jiajie; Lu, Jianjian; Zhang, Chao; Xu, Meibang; Zeng, Haifeng; Li, Shuyuan; Sun, Xuejian
The purpose of this study was to determine the changes in teeth and hard tissues after preoperative modeling and bimaxillary anterior subapical osteotomy for the treatment of bimaxillary protrusion. Cephalometric analysis was used to evaluate the aesthetic effects and occlusal relationships obtained. The subjects included 19 women and 1 man (aged 19-41 years; average, 29 years) with bimaxillary protrusion who underwent anterior subapical osteotomy of both the maxilla and mandible, with simultaneous genioplasty, if required. Based on a preoperative computer-aided manufacturing/design-assisted and model surgical design and an occlusal guide plate, new occlusal relationships were established for the patients. In addition, the preoperative and postoperative cephalometric radiographs were systematically analyzed. In all patients, the surgical incisions underwent primary healing, with no infection or osteonecrosis. Significant differences were observed in the preoperative and postoperative values of all hard tissue and teeth parameters, except for SGn-FH degrees and Co-MP. The most obvious significant differences were seen in L1-OP°, Id-Pog-Go°, IIA°, U1E-Apog, L1E-Apog, U1E-NA, and L1-NA° (P < 0.001). Postoperative follow-up lasted for 12 to 36 months. All patients eventually achieved normal jaw relationships, tooth arch forms, and Spee curves. No evident irregularities of teeth arrangement or abnormal occlusal relationships were observed. All patients were satisfied with their postoperative facial appearance, except for 1 patient, who underwent repeat surgery because of relapse. With the use of a precise preoperative model surgical design, orthognathic surgery, a simple and time-saving technique, can be used to correct bimaxillary protrusion with satisfactory postoperative occlusal relationship and facial aesthetic appearance and minimal postoperative complications.
Jo, A-Ra; Lee, Kee-Joon; Sung, Sang-Jin; Chun, Youn-Sic
Objective The aim of this study was to investigate the three-dimensional (3D) position of the center of resistance of 4 mandibular anterior teeth, 6 mandibular anterior teeth, and the complete mandibular dentition by using 3D finite-element analysis. Methods Finite-element models included the complete mandibular dentition, periodontal ligament, and alveolar bone. The crowns of teeth in each group were fixed with buccal and lingual arch wires and lingual splint wires to minimize individual tooth movement and to evenly disperse the forces onto the teeth. Each group of teeth was subdivided into 0.5-mm intervals horizontally and vertically, and a force of 200 g was applied on each group. The center of resistance was defined as the point where the applied force induced parallel movement. Results The center of resistance of the 4 mandibular anterior teeth group was 13.0 mm apical and 6.0 mm posterior, that of the 6 mandibular anterior teeth group was 13.5 mm apical and 8.5 mm posterior, and that of the complete mandibular dentition group was 13.5 mm apical and 25.0 mm posterior to the incisal edge of the mandibular central incisors. Conclusions Finite-element analysis was useful in determining the 3D position of the center of resistance of the 4 mandibular anterior teeth group, 6 mandibular anterior teeth group, and complete mandibular dentition group. PMID:28127536
Ammirati, Mario; Ma, Jianya; Canalis, Rinaldo; Martin, Neil; Black, Keith; Cheatham, Mel; Bloch, Joseph; Becker, Donald
Surgical exposure of the clivus is difficult because of its proximity to vital neurovascular structures. The anatomic bases of a new surgical approach to this area are discussed. A supra-auricular skin incision is extended toward the posterior border of the sternocleidomastoid muscle. The vertebral artery is exposed from C2 to the occiput unroofing the foramen transversarium of C1. The bone removal consists of a posterior temporal craniotomy, a suboccipital craniectomy, including mastoidectomy with sigmoid sinus unroofing, removal of the lateral margin of the foramen magnum, of the medial third of the occipital condyle, and retrolabyrinthine petrous drilling. Posterior retraction of the vertebral artery facilitates occipital condyle drilling. Intradural exposure of the petroclival region is achieved by L-shaped cutting of the dura with the long branch placed infratentorially anterior to the sigmoid sinus. Intradural exposure of the craniospinal/upper cervical areas is achieved by cutting of the dura medial to the distal sigmoid sinus and by longitudinal cutting of the dura anterior to the vertebral artery. This approach allows multiple ports of entry to the clivus with full control of the vertebrobasilar system, and of the dural sinuses, and is anatomically suited for controlled removal of tumors located in these areas. This approach, or segments of it, has been used successfully in the treatment of large neoplasms of the craniovertebral junction. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11 PMID:17170911
Houshyari, Mohammad; Kashi, Amir Shahram Yousefi; Varaki, Sakineh Soleimani; Rakhsha, Afshin; Blookat, Eftekhar Rajab
Background: The treatment of lymph nodes engaged in breast cancer with radiotherapy leads to improved locoregional control and enhanced survival rates in patients after surgery. The aim of this study was to compare two treatment techniques, namely single anterior posterior (AP) supraclavicular field with plan depth and two anterior and posterior opposed (AP/PA) supraclavicular fields. In the study, we also examined the relationships between the depth of supraclavicular lymph nodes (SCLNs) and the diameter of the wall of the chest and body mass index (BMI). Methods: Forty patients with breast cancer were analyzed using computed tomography (CT) scans. In planning target volume (PTV), the SCLNs and axillary lymph nodes (AXLNs) were contoured, and, with the attention to PTV, supraclavicular (SC) depth was measured. The dosage that reached the aforementioned lymph nodes and the level of hot spots were investigated using two treatment methods, i.e., 1) AP/PA and 2) AP with three-dimensional (3D) planning. Each of these methods was analyzed using the program Isogray for the 6 MV compact accelerator, and the diameter of the wall of the chest was measured using the CT scan at the center of the SC field. Results: Placing the plan such that 95% of the target volume with 95% or greater of the prescribed dose of 50 Gy (V95) had ≥95% concordance in both treatment techniques. According to the PTV, the depth of SCLNs and the diameter of the wall of the chest were 3–7 and 12–21cm, respectively. Regression analysis showed that the mean SC depth (the mean Plan depth) and the mean diameter of the wall of the chest were related directly to BMI (p<0.0001, adjusted R2=0.67) and (p<0.0001, adjusted R2=0.71), respectively. Conclusion: The AP/PA treatment technique was a more suitable choice of treatment than the AP field, especially for overweight and obese breast cancer patients. However, in the AP/PA technique, the use of a single-photon, low energy (6 MV) caused more hot spots
Houshyari, Mohammad; Kashi, Amir Shahram Yousefi; Varaki, Sakineh Soleimani; Rakhsha, Afshin; Blookat, Eftekhar Rajab
The treatment of lymph nodes engaged in breast cancer with radiotherapy leads to improved locoregional control and enhanced survival rates in patients after surgery. The aim of this study was to compare two treatment techniques, namely single anterior posterior (AP) supraclavicular field with plan depth and two anterior and posterior opposed (AP/PA) supraclavicular fields. In the study, we also examined the relationships between the depth of supraclavicular lymph nodes (SCLNs) and the diameter of the wall of the chest and body mass index (BMI). Forty patients with breast cancer were analyzed using computed tomography (CT) scans. In planning target volume (PTV), the SCLNs and axillary lymph nodes (AXLNs) were contoured, and, with the attention to PTV, supraclavicular (SC) depth was measured. The dosage that reached the aforementioned lymph nodes and the level of hot spots were investigated using two treatment methods, i.e., 1) AP/PA and 2) AP with three-dimensional (3D) planning. Each of these methods was analyzed using the program Isogray for the 6 MV compact accelerator, and the diameter of the wall of the chest was measured using the CT scan at the center of the SC field. Placing the plan such that 95% of the target volume with 95% or greater of the prescribed dose of 50 Gy (V95) had ≥95% concordance in both treatment techniques. According to the PTV, the depth of SCLNs and the diameter of the wall of the chest were 3-7 and 12-21cm, respectively. Regression analysis showed that the mean SC depth (the mean Plan depth) and the mean diameter of the wall of the chest were related directly to BMI (p<0.0001, adjusted R(2)=0.67) and (p<0.0001, adjusted R(2)=0.71), respectively. The AP/PA treatment technique was a more suitable choice of treatment than the AP field, especially for overweight and obese breast cancer patients. However, in the AP/PA technique, the use of a single-photon, low energy (6 MV) caused more hot spots than usual.
Homologies of muscles of the m. transversospinalis group in the dorsal and cervical regions in Sauria are established based on detailed dissections and published accounts of lepidosaurs, crocodylians, and birds. Attachments and directions of tendons comprising this muscle group are fairly conserved among the saurian clades, enabling rather robust inferences on muscle homologies. The innervation pattern indicates that mm. ascendentes are the most lateral muscles of the m. transversospinalis group in Aves, and are inferred to be homologous with the crocodylian m. tendinoarticularis based on their topological similarities. It is suggested here that the lepidosaurian articulo-parietalis part of m. longissimus cervico-capitis actually belongs to the m. transversospinalis group because its tendons of origin are shared with those of m. semispinalis. The avian m. complexus and the lateral part of the crocodylian m. transversospinalis capitis have origins and insertions similar to this lepidosaurian muscle, and are proposed to be homologous with the latter. In some birds, m. longus colli dorsalis, pars profunda continues directly into the anterior cervical region as m. splenius accessorius, suggesting a serially homologous relationship. Similarly, m. splenius anticus continues anteriorly from m. longus colli dorsalis, pars cranialis, and both of these muscles lie dorsal to m. splenius accessorius. Therefore, the currently used nomenclature that regards m. splenius accessorius as a part of m. longus colli dorsalis, pars cranialis and that regards m. splenius anticus as a part of the former muscle does not accurately reflect the serial homologies among these muscles and may not be justified. Copyright 2004 Wiley-Liss, Inc.
Jahn, Andrew; Nee, Derek Evan; Alexander, William H; Brown, Joshua W
A number of theories have been proposed to account for the role of anterior cingulate cortex (ACC) and the broader medial prefrontal cortex (mPFC) in cognition. The recent Prediction of Response Outcome (PRO) computational model casts the mPFC in part as performing two theoretically distinct functions: learning to predict the various possible outcomes of actions, and then evaluating those predictions against the actual outcomes. Simulations have shown that this new model can account for an unprecedented range of known mPFC effects, but the central theory of distinct prediction and evaluation mechanisms within ACC remains untested. Using combined computational neural modeling and fMRI, we show here that prediction and evaluation signals are indeed each represented in the ACC, and furthermore, they are represented in distinct regions within ACC. Our task independently manipulated both the number of predicted outcomes and the degree to which outcomes violated expectancies, the former providing assessment of regions sensitive to prediction and the latter providing assessment of regions sensitive to evaluation. Using quantitative regressors derived from the PRO computational model, we show that prediction-based model signals load on a network including the posterior and perigenual ACC, but outcome evaluation model signals load on the mid-dorsal ACC. These findings are consistent with distinct prediction and evaluation signals as posited by the PRO model and provide new perspective on a large set of known effects within ACC.
Ozturk, Ayla; Potluri, Anitha; Vieira, Alexandre R
The aim of this study was to examine and describe the topography of the mandibular canal (MC) in both vertical and occlusal dimensions. Fifty-two adult skulls deposited in the University of Pittsburgh School of Dental Medicine skull collection were evaluated in this study. Cone-beam computerized tomographic scans of each skull were obtained. The vertical course of MC was classified into 3 types: straight projection (12.2%), catenary-like configuration (51.1%), and progressive descent from posterior to anterior (36.7%). The evaluation of the buccolingual dimension showed that the mandibular canal was located either in contact with or close to the lingual cortical plate (≤ 2 mm) in the molar region of the majority of the cases. As it proceeds anteriorly it moves toward the buccal aspect of the mandible, where it finally emerges through the mental foramen. Three emerging patterns of mandibular canal were observed: sharp turn (53.2%), soft curved exit (28.8%), and straight path (17.4%). The examination of the vertical dimension showed that the canal was located almost 1 cm above the inferior border of the mandible and then ascended to reach the mental foramen, which is located ~16 mm (range 13.4-20.3 mm) above the inferior border of the mandible. We found a strong correlation between height of the mandible and location of the mental foramen (r = 0.64; P < .0001). The course of mandibular canal described in vertical and axial dimensions and variation in its path have been classified. In addition to variation in location of MC, it has different anatomic configurations which clinicians should be familiar with in any surgical procedures involving the posterior mandible. Copyright Â© 2012 Elsevier Inc. All rights reserved.
The present study examined the areal and laminar distribution of direct projections from the anterior thalamic nuclei to the retrohippocampal region in the rat, with anterograde transport of Phaseolus vulgaris-leucoagglutinin. The anteromedial nucleus (AM) projects to the temporal subiculum, medial entorhinal area, perirhinal area, and caudomedial part of the lateral entorhinal area. The interanteromedial nucleus (IAM) projects to the perirhinal area and the caudolateral part of the lateral entorhinal area. Furthermore, both the AM and IAM project to the temporal area 2, occipital area 1, and lateral occipital area 2. The projections from the AM and IAM to these retrohippocampal and neocortical regions terminate mainly in deep layers. The anteroventral nucleus (AV) projects to the subicular complex with a complex topographic organization. The most rostral part of the AV projects to layers I and III of the ventral presubiculum, the pyramidal cell layer of the temporal subiculum, and deep layers of the parasubiculum and medial entorhinal area. At the midrostrocaudal level of the AV, the lateral and the dorsal quadrants of the AV project, respectively, to layers I and III and to layers I and IV-VI of the ventral presubiculum, whereas the ventral and the medial quadrants project, respectively, to layers I and III and to layers I and IV-VI of the dorsal presubiculum. Furthermore, the lateral and dorsal quadrants project to the pyramidal cell layer of the temporal subiculum, whereas the ventral and medial quadrants project more septally. At the caudal third level of the AV, the dorsolateral part projects to layers I and III of the presubiculum with a patchy pattern and to the pyramidal cell layer of the septal subiculum. The anterodorsal nucleus projects mainly to deep layers of the presubiculum, parasubiculum, and entorhinal area. The results show that each subdivision of the anterior thalamic nuclei projects to a distinct field in the retrohippocampal region. This
Bayar, Ahmet; Sarikaya, Selda; Keser, Selçuk; Ozdolap, Senay; Tuncay, Ibrahim; Ege, Ahmet
Bone mineral density (BMD) loss is one of the secondary problems occurring in knee joint after injury of anterior cruciate ligament (ACL). The effect of this injury on BMDs of specific regions is not clear. The aim of this study was to investigate BMD changes in unreconstructed ACL-deficient knees with subregion analysis of dual energy X-ray absorptiometry (DEXA). Precision and reliability studies of DEXA revealed that two region of interests (ROI) in medial condyle, two ROIs in lateral femoral condyle (LFC) and one ROI in medial tibial plateau (MTP) in anteroposterior (AP) DXA view and one ROI for each of distal femur, proximal tibia and patella in lateral view had high reproducibility and reliability. Thirty-two patients with complete ACL ruptures were collected for the study and uninjured sides served as the control. All the patients were male with a mean age of 30 years. Mean duration of ACL rupture was 24 months. There were significant BMD losses in both ROIs of LFC and ROI of MTP in AP view and all three ROIs of lateral view. Greatest BMD losses in AP and lateral views were at MTP and patella respectively. There was a significant association between patellar BMD loss and duration after trauma. Bone bruises in lateral condyle might be the cause of selective involvement of LFC. Periarticular bone mineral loss in ACL-deficient knees has a predilection for the specified region of interest rather than uniform periarticular loss. This may be important for graft fixation or a factor in tunnel enlargement.
Kraemer, William J; Flanagan, Shawn D; Volek, Jeff S; Nindl, Bradley C; Vingren, Jakob L; Dunn-Lewis, Courtenay; Comstock, Brett A; Hooper, David R; Szivak, Tunde K; Looney, David P; Maresh, Carl M; Hymer, Wesley C
The anterior pituitary gland (AP) increases growth hormone (GH) secretion in response to resistance exercise (RE), but the nature of AP adaptations to RE is unknown. To that end, we examined the effects of RE on regional AP somatotroph GH release, structure, and relative quantity. Thirty-six Sprague-Dawley rats were assigned to one of four groups: 1) no training or acute exercise (NT-NEX); 2) no training with acute exercise (NT-EX); 3) resistance training without acute exercise (RT-NEX); 4) resistance training with acute exercise (RT-EX). RE incorporated 10, 1 m-weighted ladder climbs at an 85° angle. RT groups trained 3 days/wk for 7 wk, progressively. After death, trunk blood was collected, and each AP was divided into quadrants (ventral-dorsal and left-right). We measured: 1) trunk plasma GH; 2) somatotroph GH release; 3) somatotroph size; 4) somatotroph secretory content; and 5) percent of AP cells identified as somatotrophs. Trunk GH differed by group (NT-NEX, 8.9 ± 2.4 μg/l; RT-NEX, 9.2 ± 3.5 μg/l; NT-EX, 15.6 ± 3.4 μg/l; RT-EX, 23.4 ± 4.6 μg/l). RT-EX demonstrated greater somatotroph GH release than all other groups, predominantly in ventral regions (P < 0.05-0.10). Ventral somatotrophs were larger in NT-EX and RT-NEX compared with RT-EX (P < 0.05-0.10). RT-NEX exhibited significantly greater secretory granule content than all other groups but in the ventral-right region only (P < 0.05-0.10). Our findings indicate reproducible patterns of spatially distinct, functionally different somatotroph subpopulations in the rat pituitary gland. RE training appears to induce dynamic adaptations in somatotroph structure and function.
Shah, Ankit H; Shah, Darshit H
Accurate diagnosis and treatment planning are essential for obtaining ideal treatment result in cases involving mandibular incisor extraction. This case report describes a 15-year-old female with balanced soft-tissue profile, peg-shaped maxillary lateral incisors, and moderate mandibular anterior crowding treated with a mandibular incisor extraction. Ideal overbite and overjet were achieved. “Black triangle” formation was avoided due to the bodily movement of mandibular incisors and the use of uprighting springs for ideal axial inclination of mandibular incisors. A mandibular incisor extraction can be an effective treatment option in carefully selected clinical situations. PMID:27556022
Renders, G A P; Mulder, L; van Ruijven, L J; van Eijden, T M G J
Quantification of porosity and degree of mineralization of bone facilitates a better understanding of the possible effects of adaptive bone remodelling and the possible consequences for its mechanical properties. The present study set out first to give a three-dimensional description of the cortical canalicular network in the human mandibular condyle, in order to obtain more information about the principal directions of stresses and strains during loading. Our second aim was to determine whether the amount of remodelling was larger in the trabecular bone than in cortical bone of the condyle and to establish whether the variation in the amount of remodelling was related to the surface area of the cortical canals and trabeculae. We hypothesized that there were differences in porosity and orientation of cortical canals between various cortical regions. In addition, as greater cortical and trabecular porosities are likely to coincide with a greater surface area of cortical canals and trabeculae available for osteoblastic and osteoclastic activity, we hypothesized that this surface area would be inversely proportional to the degree of mineralization of cortical and trabecular bone, respectively. Micro-computed tomography was used to quantify porosity and mineralization in cortical and trabecular bone of ten human mandibular condyles. The cortical canals in the subchondral cortex of the condyle were orientated in the mediolateral direction, and in the anterior and posterior cortex in the superoinferior direction. Cortical porosity (average 3.5%) did not differ significantly between the cortical regions. It correlated significantly with the diameter and number of cortical canals, but not with cortical degree of mineralization. In trabecular bone (average porosity 79.3%) there was a significant negative correlation between surface area of the trabeculae and degree of mineralization; such a correlation was not found between the surface area of the cortical canals and the
Torroni, Andrea; Marianetti, Tito Matteo; Romandini, Mario; Gasparini, Giulio; Cervelli, Daniele; Pelo, Sandro
Traumas, malformative or dysplastic pathologies, atrophy, osteoradionecrosis, and benign or malignant neoplasm can cause bone deficits in the mandible. Consequent mandibular defects can determine aesthetic and functional problems; therefore, being able to perform a good reconstruction is of critical importance.Several techniques have been proposed for mandibular reconstruction over the years. In this article, we present and discuss the evolution during the time of the methods of mandible reconstruction as well as pros and cons of each procedure on the basis of experience of 10 years in the maxillofacial department of the Catholic University of Sacred Heart of Rome.Free flaps represent the gold standard method of reconstruction of large mandibular defects: the fibula bone flap represents the best choice for large defects involving the arch and the mandibular ramus, whereas the deep circumflex iliac artery represents a valid alternative for mandibular defects involving the posterior region.In cases where free flap reconstructions are contraindicated, the use of regional pedicle flap combined with autologous bone grafts still represents a valid choice. Patients who are not deemed suitable for long and demanding surgery can still be treated using alloplastic materials in association with regional pedicle flap or, when adjuvant radiation therapy is needed, by simple locoregional pedicle flap. Finally, in selected cases, the bone transporting technique should be considered as a valid alternative to the more "traditional" reconstructive methods because of the extraordinary potential and its favorable cost-benefit ratio.
Herranz-Aparicio, Judit; Marques, José; Almendros-Marqués, Nieves
Background In order to choose the appropriate implant size and to prevent complications, an oral surgeon must know the size and shape of the mandible. In the posterior mandibular region, a lingual undercut is often found and could represent a difficulty hard to manage if a lingual or buccal perforation occur. A large series of computed tomography (CT) images of the mandibular first molar was evaluated and the bone morphology, the prevalence and the degree of the lingual concavity in the first molar region were studied. Material and Methods One hundred and fifty-one computed tomography (CT) examinations of patients were retrospectively evaluated to determine anatomical variations in bone morphology in the submandibular fossa region. Results A total of 151 subjects were included, consisting of 64 males (M) (42.4%) and 87 females (F) (57.6%). The under-cut type ridge was present in 64.2% of the cases. The concavity angle was 66.6 ± 8.9° (M) and 71.6 ± 8.4° (F) and the linear concavity depth 4.5 ± 2.3 mm (M) and 3.1 ± 1.7 mm (F) (p>0.05). Conclusions Mandibles with any lingual concavity present a potential increased risk of lingual cortical perforation during implant placement surgery. CT imaging allows characterizing the anatomy of the submandibular fossa and provides other important information for the preoperative assessment of the posterior mandible for dental implants placement. Key words:Anatomy, computed tomography, dental implants, intraoperative complications, mandible, panoramic radiography, radiographic examination. PMID:27694785
Nelson, Gerald; Ahn, Hyo-Won; Jeong, Sung-Hee; Kim, Jun-Shik; Kim, Seong-Hun; Chung, Kyu-Rhim
Vertical dimension control is critical for adults with Class II high-angle malocclusions. If the patient has a temporomandibular disorder, this requirement is exacerbated. When extraction is planned, the treatment challenge is further increased. This article reports on a new biomechanical design (C-therapy) appropriate for anterior segment retraction with excellent control of the vertical dimension, even in a Class II high-angle patient with a temporomandibular disorder. Maximum retraction of the maxillary anterior segment can be achieved with a lingual retractor and a palatal miniplate without appliances on the maxillary posterior segments. Mandibular anterior vertical height was well controlled by a second miniplate in the mental region. This device also contributed to mandibular anchorage reinforcement. A patient with temporomandibular disorder symptoms treated with this approach is shown.
Norman-Haignere, Sam; Kanwisher, Nancy; McDermott, Josh H
Pitch is a defining perceptual property of many real-world sounds, including music and speech. Classically, theories of pitch perception have differentiated between temporal and spectral cues. These cues are rendered distinct by the frequency resolution of the ear, such that some frequencies produce "resolved" peaks of excitation in the cochlea, whereas others are "unresolved," providing a pitch cue only via their temporal fluctuations. Despite longstanding interest, the neural structures that process pitch, and their relationship to these cues, have remained controversial. Here, using fMRI in humans, we report the following: (1) consistent with previous reports, all subjects exhibited pitch-sensitive cortical regions that responded substantially more to harmonic tones than frequency-matched noise; (2) the response of these regions was mainly driven by spectrally resolved harmonics, although they also exhibited a weak but consistent response to unresolved harmonics relative to noise; (3) the response of pitch-sensitive regions to a parametric manipulation of resolvability tracked psychophysical discrimination thresholds for the same stimuli; and (4) pitch-sensitive regions were localized to specific tonotopic regions of anterior auditory cortex, extending from a low-frequency region of primary auditory cortex into a more anterior and less frequency-selective region of nonprimary auditory cortex. These results demonstrate that cortical pitch responses are located in a stereotyped region of anterior auditory cortex and are predominantly driven by resolved frequency components in a way that mirrors behavior.
Kanwisher, Nancy; McDermott, Josh H.
Pitch is a defining perceptual property of many real-world sounds, including music and speech. Classically, theories of pitch perception have differentiated between temporal and spectral cues. These cues are rendered distinct by the frequency resolution of the ear, such that some frequencies produce “resolved” peaks of excitation in the cochlea, whereas others are “unresolved,” providing a pitch cue only via their temporal fluctuations. Despite longstanding interest, the neural structures that process pitch, and their relationship to these cues, have remained controversial. Here, using fMRI in humans, we report the following: (1) consistent with previous reports, all subjects exhibited pitch-sensitive cortical regions that responded substantially more to harmonic tones than frequency-matched noise; (2) the response of these regions was mainly driven by spectrally resolved harmonics, although they also exhibited a weak but consistent response to unresolved harmonics relative to noise; (3) the response of pitch-sensitive regions to a parametric manipulation of resolvability tracked psychophysical discrimination thresholds for the same stimuli; and (4) pitch-sensitive regions were localized to specific tonotopic regions of anterior auditory cortex, extending from a low-frequency region of primary auditory cortex into a more anterior and less frequency-selective region of nonprimary auditory cortex. These results demonstrate that cortical pitch responses are located in a stereotyped region of anterior auditory cortex and are predominantly driven by resolved frequency components in a way that mirrors behavior. PMID:24336712
Nakamura, Masahiro; Matsumura, Tatsushi; Yamashiro, Takashi; Iida, Seiji; Kamioka, Hiroshi
We report a case involving a young female patient with severe mandibular retrognathism accompanied by mandibular condylar deformity that was effectively treated with Le Fort I osteotomy and two genioplasty procedures. At 9 years and 9 months of age, she was diagnosed with Angle Class III malocclusion, a skeletal Class II jaw relationship, an anterior crossbite, congenital absence of some teeth, and a left-sided cleft lip and palate. Although the anterior crossbite and narrow maxillary arch were corrected by interceptive orthodontic treatment, severe mandibular hypogrowth resulted in unexpectedly severe mandibular retrognathism after growth completion. Moreover, bilateral condylar deformities were observed, and we suspected progressive condylar resorption (PCR). There was a high risk of further condylar resorption with mandibular advancement surgery; therefore, Le Fort I osteotomy with two genioplasty procedures was performed to achieve counterclockwise rotation of the mandible and avoid ingravescence of the condylar deformities. The total duration of active treatment was 42 months. The maxilla was impacted by 7.0 mm and 5.0 mm in the incisor and molar regions, respectively, while the pogonion was advanced by 18.0 mm. This significantly resolved both skeletal disharmony and malocclusion. Furthermore, the hyoid bone was advanced, the pharyngeal airway space was increased, and the morphology of the mandibular condyle was maintained. At the 30-month follow-up examination, the patient exhibited a satisfactory facial profile. The findings from our case suggest that severe mandibular retrognathism with condylar deformities can be effectively treated without surgical mandibular advancement, thus decreasing the risk of PCR. PMID:27896214
Zhou, Zhixuan; Chen, Wu; Shen, Ming; Sun, Chao; Li, Jun; Chen, Ning
To provide an anatomical basis for clinical implant esthetics, we evaluated the morphology of the nasopalatine canal (NPC) and analyzed labial and interproximal bone anatomy at the maxillary anterior region. We sought to investigate the effect of maxillary protrusion and tooth labiolingual inclination on labial bone anatomy in Chinese adults. Three dimensional (3D) images were reconstructed using cone-beam computed tomography (CBCT) images from 80 Chinese subjects and by SimPlant 11.04. The dimensions of the NPC, the thickness and profile of the labial bone, the width and height of the interproximal bone, angle sella-nasion-subspinale (SNA) and angle upper central incisor-nasion,subspinale (U1-NA) were measured. The incisive foramen of the NPC was markedly wider than its nasal foramen. The dimension of its labial bone wall demonstrated an increasing width from the crestal to apical measurements. The labial bone at the maxillary anterior region was rather thin, especially at 3 mm below the cemento-enamel junction (CEJ) and the mid-root level; the profile of the labial bone was more curved at the central incisor, and the interproximal bone became wider and shorter posteriorly. There were significant relationships between maxillary protrusion and labial bone profile, tooth labiolingual inclination and labial bone thickness (P < 0.02). To achieve optimal esthetic outcome of implant, bone augmentation is necessary at the maxillary anterior region. For immediate or early placement at the maxillary anterior region, the implant should be located palatally to reduce labial bone resorption and marginal recession; its apex should be angulated palatally to avoid labial perforation at the apical region. To protect the NPC, implants at the central incisor region should be placed away from NPC. PMID:25469120
Yasar, Fusun; Akgunlu, Faruk
The aim was to assess whether Fractal Dimension and Lacunarity analysis can discriminate patients having different mandibular cortical shape. Panoramic radiographs of 52 patients were evaluated for mandibular cortical index. Weighted Kappa between the observations were varying between 0.718-0.805. These radiographs were scanned and converted to binary images. Fractal Dimension and Lacunarity were calculated from the regions where best represents the cortical morphology. It was found that there were statistically significant difference between the Fractal Dimension and Lacunarity of radiographs which were classified as having Cl 1 and Cl 2 (Fractal Dimension P:0.000; Lacunarity P:0.003); and Cl 1 and Cl 3 cortical morphology (Fractal Dimension P:0.008; Lacunarity P:0.001); but there was no statistically significant difference between Fractal Dimension and Lacunarity of radiographs which were classified as having Cl 2 and Cl 3 cortical morphology (Fractal Dimension P:1.000; Lacunarity P:0.758). FD and L can differentiate Cl 1 mandibular cortical shape from both Cl 2 and Cl 3 mandibular cortical shape but cannot differentiate Cl 2 from Cl 3 mandibular cortical shape on panoramic radiographs.
Yasar, Fusun; Akgunlu, Faruk
Objectives The aim was to assess whether Fractal Dimension and Lacunarity analysis can discriminate patients having different mandibular cortical shape. Methods Panoramic radiographs of 52 patients were evaluated for mandibular cortical index. Weighted Kappa between the observations were varying between 0.718–0.805. These radiographs were scanned and converted to binary images. Fractal Dimension and Lacunarity were calculated from the regions where best represents the cortical morphology. Results It was found that there were statistically significant difference between the Fractal Dimension and Lacunarity of radiographs which were classified as having Cl 1 and Cl 2 (Fractal Dimension P:0.000; Lacunarity P:0.003); and Cl 1 and Cl 3 cortical morphology (Fractal Dimension P:0.008; Lacunarity P:0.001); but there was no statistically significant difference between Fractal Dimension and Lacunarity of radiographs which were classified as having Cl 2 and Cl 3 cortical morphology (Fractal Dimension P:1.000; Lacunarity P:0.758). Conclusions FD and L can differentiate Cl 1 mandibular cortical shape from both Cl 2 and Cl 3 mandibular cortical shape but cannot differentiate Cl 2 from Cl 3 mandibular cortical shape on panoramic radiographs. PMID:19212535
Guerrero, C A; Bell, W H; Contasti, G I; Rodriguez, A M
Transverse mandibular deficiency with crowding of the mandibular anterior teeth is frequently present in patients with Class I and II malocclusions. The hallmarks of treatment by compensating orthodontics, functional appliances or orthopaedic devices are instability, compromised periodontium and compromised facial aesthetics. A new surgical technique has been developed to widen the mandible. The method is based upon gradual osteodistraction following vertical interdental symphyseal osteotomy. Ten patients with transverse mandibular deficiency and significant dental crowding were treated by symphyseal distraction and subsequent non-extraction decompensating orthodontic treatment. Either an intraoral tooth-borne Hyrax appliance or a new custom-made bone-borne osteodistractor was used to gradually widen the mandible. The surgical procedures were accomplished under local anaesthesia and intravenous sedation in an ambulatory surgical setting using an individualized distraction protocol. The appliances were activated 7 days after symphyseal osteotomies, once each day at a rate of 1 mm per day and stabilized for 30-40 days after distraction. After the segments were distracted, non-extraction orthodontic alignment of the mandibular anterior teeth was accomplished. The symphyseal distraction gaps were bridged by new bony regenerate. Distraction osteogenesis provided an efficient surgical alternative to orthognathic surgery for widening the mandible and treatment of transverse mandibular deficiency without extraction of teeth.
Shaw, R M; Molyneux, G S
The effect of a reduced functional dentition on the development of the mandibular disc in young rabbits was studied by measuring cell proliferation within the disc following tooth extraction. Maxillary and mandibular incisor teeth were extracted from 18 animals at 5 weeks of age. At 12 weeks the rabbits received 0.25 mg/kg vincristine sulphate. Groups of three animals were killed 1.5, 3, 6, 12, 24 and 48 h after the injection of vincristine and the mitotic rate determined across the anterior, intermediate and posterior bands of the disc. Eighteen age- and sex-matched control rabbits with intact dentitions were treated in parallel. In the absence of incisor teeth, reflex gnawing and incising failed to develop, resulting in altered jaw movements and muscle force requirements. The mitotic rate in the anterior band was reduced significantly (p = 0.0117); rates for the intermediate and posterior bands were not significantly affected. There was an associated reduction in alveolar bone mass and deformation of the developing craniomandibular complex. As the lateral pterygoid inserts into the anterior band of the mandibular disc, it is proposed that altered activity within this muscle, combined with a modified loading of the joints, both secondary to incisor removal, resulted in a reduced mitotic rate in the anterior band of the developing mandibular disc.
Akça, Kivanç; Akkocaoglu, Murat; Cömert, Ayhan; Tekdemir, Ibrahim; Cehreli, Murat Cavit
To compare the biomechanical effect of splinted versus unsplinted mandibular implants supporting overdentures subjected to experimental static immediate load on bone tissue deformation using strain gauge analysis. Strain gauges were bonded on the labial cortical bone adjacent to 2 Straumann dental implants placed in the mandibular interforaminal region of 4 completely edentulous mandibles of fresh human cadavers. The installation torque value (ITV) of each implant was measured using a custom-made torque wrench, and implant stability quotients (ISQs) were also obtained using resonance frequency analysis. Three overdentures (ODs), 2 splinted (bar- and cantilevered bar-retained) and 1 unsplinted (ball-retained), were fabricated for each edentulous mandible. Two experimental loads were applied subsequently via 2 miniature load cells that were placed bilaterally 10 mm (anterior loading) and 15 mm (posterior loading) from the implant. Strain measurements were performed at a sample rate of 10 KHz and under a maximum experimental static load of 100 N; they were simultaneously monitored from a computer connected to a data acquisition system. Finally, the removal torque values (RTV) of the implants were measured. Strains on the labial cortical bone around implants supporting mandibular ODs under anterior loading were significantly higher than measured under posterior loading for all attachment types (P < .05). All strain values were compressive in nature, and the minimum strain (-19 microepsilon) was recorded for bar-retained ODs under 25 N posterior loading, while the maximum strain (-797 microepsilon) was for recorded for retentive anchor-retained ODs under 100 N anterior loading. Nonparametric correlations between ISQs, ITVs, and RTVs identified significant correlations only for ITVs and RTVs (P < .05). Splinting of 2 interforaminal dental implants, regardless of attachment type, to support mandibular ODs subjected to immediate load significantly reduced initial bone
CUSTODIO, William; GOMES, Simone Guimarães Farias; FAOT, Fernanda; GARCIA, Renata Cunha Matheus Rodrigues; DEL BEL CURY, Altair Antoninha
Objective The aim of this study was to evaluate whether vertical facial patterns influence maximal occlusal force (MOF), masticatory muscle electromyographic (EMG) activity, and medial mandibular flexure (MMF). Material and Methods Seventy-eight dentate subjects were divided into 3 groups by Ricketts's analysis: brachyfacial, mesofacial and dolychofacial. Maximum occlusal force in the molar region was bilaterally measured with a force transducer. The electromyographic activities of the masseter and anterior temporal muscles were recorded during maximal voluntary clenching. Medial mandibular flexure was calculated by subtracting the intermolar distance of maximum opening or protrusion from the distance in the rest position. The data were analyzed using ANOVA followed by Tukey's HSD test. The significance level was set at 5%. Results Data on maximum occlusal force showed that shorter faces had higher occlusal forces (P<0.0001). Brachyfacial subjects presented higher levels of masseter electromyographic activity and medial mandibular flexure, followed by the mesofacial and dolychofacial groups. Additionally, dolychofacial subjects showed significantly lower electromyographic temporalis activities (P<0.05). Conclusion Within the limitations of the study, it may be concluded that maximum occlusal force, masticatory muscle activity and medial mandibular flexure were influenced by the vertical facial pattern. PMID:21655772
Tehranchi, Azita; Behnia, Hossein; Younessian, Farnaz; Ghochani, Mostafa Sadeghi
Mandibular fractures are among the most common facial injuries. This case report demonstrates the efficacy of simultaneous usage of miniscrews and direct bonding techniques without open reduction in an extensive traumatized patient. A 25-year-old girl with multiple injuries in the head and facial region 1 month after a plane crash accident was referred to manage the mandibular fractures. Due to the presence of multiple injuries, a conservative treatment of symphysiseal fracture was performed. In order to keep the fractured fragments of the mandible close together, the anterior teeth of the lower arch were tied by means of the orthodontic wire. Ten miniscrews were used to improve the anchorage units and also, settling the occlusion by means of light intermaxillary elastics. Following the active treatment, clinical and radiographic analysis showed satisfactory healing without any periodontal involvement of the teeth in the fracture line. PMID:24348629
Park, Young-Wook; Lee, Woo-Young; Kwon, Kwang-Jun; Kim, Seong-Gon; Lee, Suk-Keun
Osteochondroma is rarely reported in the maxillofacial region; however, it is prevalent in the mandibular condyle. This slowly growing tumor may lead to malocclusion and facial asymmetry. A 39-year-old woman complained of gradual development of anterior and posterior unilateral crossbite, which resulted in facial asymmetry. A radiological study disclosed a large tumor mass on the top of the left mandibular condyle. This bony tumor was surgically removed through condylectomy and the remaining condyle head was secured. Subsequently, bimaxillary orthognathic surgery was performed to correct facial asymmetry and malocclusion. Pathological diagnosis was osteochondroma; immunohistochemistry showed that the tumor exhibited a conspicuous expression of BMP-4 and BMP-2 but rarely expression of PCNA. There was no recurrence at least for 1 year after the operation. Patient's functional and esthetic rehabilitation was uneventful.
Ebisch, Sjoerd J H; Gallese, Vittorio; Willems, Roel M; Mantini, Dante; Groen, Wouter B; Romani, Gian Luca; Buitelaar, Jan K; Bekkering, Harold
Impaired understanding of others' sensations and emotions as well as abnormal experience of their own emotions and sensations is frequently reported in individuals with Autism Spectrum Disorder (ASD). It is hypothesized that these abnormalities are based on altered connectivity within "shared" neural networks involved in emotional awareness of self and others. The insula is considered a central brain region in a network underlying these functions, being located at the transition of information about bodily arousal and the physiological state of the body to subjective feelings. The present study investigated the intrinsic functional connectivity properties of the insula in 14 high-functioning participants with ASD (HF-ASD) and 15 typically developing (TD) participants in the age range between 12 and 20 years by means of "resting state" or "nontask" functional magnetic resonance imaging. Essentially, a distinction was made between anterior and posterior regions of the insular cortex. The results show a reduced functional connectivity in the HF-ASD group, compared with the TD group, between anterior as well as posterior insula and specific brain regions involved in emotional and sensory processing. It is suggested that functional abnormalities in a network involved in emotional and interoceptive awareness might be at the basis of altered emotional experiences and impaired social abilities in ASD, and that these abnormalities are partly based on the intrinsic functional connectivity properties of such a network.
Jena, Ashok Kumar; Singh, Satinder Pal
Advancement of mandible rather than tooth movement is an ideal treatment for the correction of Class II malocclusion resulting from mandibular retrusion. In growing patients, forward repositioning of mandible by mandibular repositioning appliances is considered as a treatment of choice. Correction of mandibular retrusion by the conventional mandibular protraction appliances (MPAs) is mainly due to dento-alveolar changes and by altering the design of original MPAs, these limitations were minimized. The modified design enhanced the mandibular growth and contributed for the better skeletal correction of Class II malocclusion as compared to the conventional MPAs. This article highlights the design and fabrication of a splinted MPA for the correction of Class II malocclusion due to mandibular retrusion and also describes a patient managed by this appliance. PMID:25821367
Gupta, Anurag; Kohli, Virender S; Hazarey, Pushpa V; Kharbanda, Om P; Gunjal, Amit
This study was designed to evaluate patterns of stress generation in the temporomandibular joint after mandibular protraction, by using a 3-dimensional finite element method. The results of the initial investigation are reported here in Part 1. The effects of varying the construction bite are reported in Part 2. A 3-dimensional computer-aided design model was developed from the magnetic resonance images of a growing boy (age, 12 years), by using I-DEAS NX (version 11.0, Siemens PLM Software, Plano, Tex). The model simulated mandibular protraction, with 5 mm of sagittal advancement and 4 mm of vertical opening. Stress distributions on the condylar neck, the glenoid fossa, and the articular disc in the anteroposterior and mediolateral directions were assessed. Tensile stresses were located on the posterosuperior aspects and compressive stresses on the anterior and anterosuperior aspects of the condylar head. Tensile stresses were found in the posterior region of the glenoid fossa near the attachment of the posterior connective tissues. These results suggest that, on mandibular protraction, the mandibular condyle experiences tensile stresses in the posterosuperior aspect that might help explain condylar growth in this direction. Similarly, on the glenoid fossa, tensile stresses are created in the region of posterior connective tissues; this might be correlated with the increased cellular activity in this region. Further study with variable vertical heights of the construction bites is needed.
Nixon, R L
The indications for mandibular anterior ceramic veneers, tooth preparation design, provisionalization considerations, and placement procedures were presented in a previous article by the author. The functional utility, tissue biocompatibility, and dissimilarities of mandibular veneers, in comparison to maxillary anterior ceramic veneers, were explored, along with indications and contraindications for this form of treatment. This article demonstrates the aesthetic range of these restorations in the context of more complex cases. The learning objective of this article is to illustrate the viability of mandibular ceramic veneers in realigning teeth nonorthodontically, while sustaining the biologic health of the periodontium, stability of the occlusion, and aesthetic parameters of each case. The importance of wax mock-ups is outlined for visualization of the final result, as well as the evaluation of root proximity to avoid subgingival ledging of the teeth and subsequent periodontal disease. Orthodontics and other methods for the correction of anterior crowding are discussed.
This study reconstructs incremental enamel development for a sample of modern human deciduous mandibular (n = 42) and maxillary (n = 42) anterior (incisors and canines) teeth. Results are compared between anterior teeth, and with previous research for deciduous molars (Mahoney: Am J Phys Anthropol 144 (2011) 204-214) to identify developmental differences along the tooth row. Two hypotheses are tested: Retzius line periodicity will remain constant in teeth from the same jaw and range from 6 to 12 days among individuals, as in human permanent teeth; daily enamel secretion rates (DSRs) will not vary between deciduous teeth, as in some human permanent tooth types. A further aim is to search for links between deciduous incremental enamel development and the previously reported eruptionsequence. Retzius line periodicity in anterior teeth ranged between 5 and 6 days, but did not differ between an incisor and molar of one individual. Intradian line periodicity was 12 h. Mean cuspal DSRs varied slightly between equivalent regions along the tooth row. Mandibular incisors initiated enamel formation first, had the fastest mean DSRs, the greatest prenatal formation time, and based upon prior studies are the first deciduous tooth to erupt. Relatively rapid development in mandibular incisors in advance of early eruption may explain some of the variation in DSRs along the tooth row that cannot be explained by birth. Links between DSRs, enamel initiation times, and the deciduous eruption sequence are proposed. Anterior crown formation times presented here can contribute toward human infant age-at-death estimates. Regression equations for reconstructing formation time in worn incisors are given.
Freihofer, H P; Hoppenreys, T J
A technique is described of true rebuilding of the mandibular crest using a combination of the visor-osteotomy (Härle, 1975) and a subperiosteal rib graft (Obwegeser, 1963 b). A preliminary report on 25 patients with a mean follow-up of 30 months leads to the following conclusions: the resorption in the anterior part ist 52% of the initial gain after 43 months. In the lateral regions 61% is lost. This compares favourably with other techniques. Impairment of sensibility, although usually acceptable, is the main drawback of the procedure.
Gemal, Hugo; Reed, Duncan
A fracture of the mandible is a common trauma presentation amongst young males and represents one of the most frequently encountered fractured bones within the viscerocranium. Historically, assault was the dominant contributing factor but now due to the increased number of vehicles used per capita, motor vehicle accidents are the primary cause. Mandibular fractures can be classified anatomically, by dentition, by muscle group and by severity. The fracture may also be closed, open, comminuted, displaced or pathological. It is important that the imaging modality used identifies the classification as this will decide definitive treatment. X-ray projections have typically been used to detect a mandibular fracture, but are limited to an anteroposterior (AP), lateral and oblique view in an unstable trauma patient. These views are inadequate to detail the level of fracture displacement and show poor detail of the condylar region. Computer tomography (CT) is the imaging modality of choice when assessing a traumatic mandibular injury and can demonstrate a 100% sensitivity in detecting a fracture. This is through use of a multidetector-row CT, which reduces motion blur and therefore produces accurate coronal and sagittal reconstructions. Furthermore, reconstructive three-dimensional CT images gained from planar views, allows a better understanding of the spatial relationship of the fracture with other anatomical landmarks. This ensures a better appreciation of the severity and classification of a mandibular fracture, which therefore influences operative planning. Ultrasound is another useful modality in detecting a mandibular fracture when the patient is too unstable to be transferred to a CT scanner. The sensitivity however is less in comparison to a CT series of images and provides limited detail on the fracture pattern. Magnetic resonance imaging demonstrates use in assessing soft tissue injury of the temporomandibular joint but this is unlikely to be of priority when
Slater, Bernard J.; Mehrabian, Zara; Guo, Yan; Hunter, Allan
Purpose Nonarteritic anterior ischemic optic neuropathy (NAION) results in optic nerve damage with retinal ganglion cell (RGC) loss. An NAION model, rodent anterior ischemic optic neuropathy (rAION), was used to determine AION-associated mechanisms of RGC death and associated regional retinal changes. Methods rAION was induced in male Wistar rats, and the retinas analyzed at various times after induction. RGCs were positively identified by both retrograde fluorogold labeling and brain-expressed X-linked protein-1/2 (Bex1/2) immunoreactivity. RGC death was analyzed by fluorescein-tagged annexin-V labeling (FITC-annexin-V), as well as by terminal nucleotide nick-end labeling (TUNEL). Retinal flatmount preparations enabled regional retinal analysis of labeled dying cells. Apoptosis pathway activation was confirmed by Western analysis, with an antibody that recognizes cleaved caspase-3. Results Post-rAION, RGCs die by apoptosis over a longer period than previously recognized. Cleaved caspase-3 immunoreactivity was greatest between 11 and 15 days. rAION-induced RGC death occurs regionally, with sparing of large contiguous regions of RGCs. Conclusions rAION results in later RGC death than in traumatic optic nerve damage models. Apoptosis, measured by FITC-annexin, occurs maximally in the second to third week after infarct. Cleaved caspase-3 activation confirms that after rAION, RGCs undergo apoptosis by the caspase activation pathway. The regional pattern in dying RGCs after rAION implies that a measure of retinotopic organization occurs in the rodent optic nerve. The prolonged period from insult to death suggests that the window for successful treatment after ON infarct may be longer than previously recognized. PMID:18660428
Kamat, Rujvi; Brown, Gregory G; Bolden, Khalima; Fennema-Notestein, Christine; Archibald, Sarah; Marcotte, Thomas D; Letendre, Scott L; Ellis, Ronald J; Woods, Steven Paul; Grant, Igor; Heaton, Robert K
Apathy is a relatively common psychiatric syndrome in HIV infection, but little is known about its neural correlates. In the present study, we examined the associations between apathy and diffusion tensor imaging (DTI) indices in key frontal white matter regions in the thalamocorticostriatal circuit, which has been implicated in the expression of apathy. Nineteen participants with HIV infection and 19 demographically comparable seronegative comparison subjects completed the Apathy subscale of the Frontal Systems Behavioral Scale as a part of a comprehensive neuropsychiatric research evaluation. When compared to the seronegative participants, the HIV+ group had significantly more frontal white matter abnormalities. Within HIV+ persons, and as predicted, higher ratings of apathy were associated with greater white matter alterations in the anterior corona radiata, genu, and orbital medial prefrontal cortex. The associations between white matter alterations and apathy were independent of depression and were stronger among participants with lower current cluster of differentiation 4 (CD4) counts. All told, these findings indicate that apathy is independently associated with white matter abnormalities in anterior, medial brain regions in persons infected with HIV, particularly in the setting of lower current immune functioning, which may have implications for antiretroviral therapy.
Kamat, Rujvi; Brown, Gregory G.; Bolden, Khalima; Fennema-Notestine, Christine; Archibald, Sarah; Marcotte, Thomas D.; Letendre, Scott L.; Ellis, Ronald J.; Woods, Steven Paul; Grant, Igor; Heaton, Robert K.
Apathy is a relatively common psychiatric syndrome in HIV infection, but little is known about its neural correlates. In the present study, we examined the associations between apathy and diffusion tensor imaging (DTI) indices in key frontal white matter regions in the thalamocorticostriatal circuit that has been implicated in the expression of apathy. Nineteen participants with HIV infection and 19 demographically comparable seronegative comparison subjects completed the Apathy subscale of the Frontal Systems Behavioral Scale as a part of a comprehensive neuropsychiatric research evaluation. When compared to the seronegative participants, the HIV+ group had significantly more frontal white matter abnormalities. Within HIV+ persons, and as predicted, higher ratings of apathy were associated with greater white matter alterations in the anterior corona radiata, genu, and orbital medial prefrontal cortex. The associations between white matter alterations and apathy were independent of depression and were stronger among participants with lower current CD4 counts. All told, these findings indicate that apathy is independently associated with white matter abnormalities in anterior, medial brain regions in persons infected with HIV, particularly in the setting of lower current immune functioning, which may have implications for antiretroviral therapy. PMID:25275424
Sailer, Irena; Zembic, Anja; Jung, Ronald Ernst; Hämmerle, Christoph Hans Franz; Mattiola, Alessandro
Implant-supported single crowns have become a valid alternative to conventional fixed dental prostheses due to their excellent clinical long-term results. However, along with good survival rates, esthetic factors are important for success in anterior regions. Today, several kinds of implant abutments are offered by implant manufacturers. A choice must be made between standardized and customized abutments; further, different abutment materials such as titanium or various ceramics (alumina, zirconia) are available. Finally, the reconstruction can be cemented on the abutment or screw-retained directly on the implant. When choosing an abutment for an anterior single-unit case, several factors should be considered: visibility of the region (eg, high vs low smile line); biotype of the gingiva; color of the neighboring teeth; and finally, esthetic expectations of the patient. In esthetically demanding situations, customized ceramic abutments are indicated. In patient situations with thin peri-implant soft tissues, zirconia abutments and all-ceramic crowns should be used in combination. In cases with thick mucosa, titanium can be used as the abutment material, combined with metal-ceramic crowns. In order to avoid difficulties removing excess cement, screw-retained reconstructions may be preferred; however, the screw access hole should be positioned palatal to the incisal edge.
The mandibular laterodeviation is one of the most evident malformations of the face, because it alters the lower third of the face. Etiologically it can be classified into: Static laterodeviations caused by teeth; Static laterodeviations caused by skeleton change: by monolateral hypertrophy (condyle, condyle and neck of the condyle, half mandible hypertrophy); by monolateral hypertrophy (congenital pathological); Dinamic laterodeviations functional. The midline displacement with posterior monolateral cross bite is caused by width discrepancy between the upper and lower dental arch resulting in a lateral shifting of the mandible. This laterodeviation is also called "laterale forced bite" or "articular cross bite". Articular cross bite is generally corrected by orthodontics during the interceptive period when the growth of the jaws is still present. In the author's opinion the orthognathic surgery is absolutely necessary for adult dental laterodeviation already stabilized. The skeletal laterodeviation must always be treated by orthognathic surgery. It is the author's practice to use the sagittal bilateral osteotomy at the angle and ramus level whose lines of osteotomy at the angle are different from one another depending on the displacement and rotation which one must do to the mandible to get contact surfaces which are larger enough to ensure proper union because the two mandibular halves have different lengths and different angles. This kind of operation normalizes the occlusion and is sometime sufficient to harmonize the oval of the lower third of the face. In the anterior part of the chin is still laterodeviated one continues with a wedge shaped osteotomy at the tip of the chin in order to reposition the tip to the midline and with an additional osteotomy at the hypertrophied angle level. If laterodeviation is joined by other bone malformations in can be considered a symptom which is more or less marked. In this case, therefore, laterodeviation is a part of a
Nuvvula, Sivakumar; Gaddam, Kumar Raja; Jayachandra, Bhumireddy; Mallineni, Sreekanth Kumar
Talon cusp is an uncommon dental anomaly showing morphologically well delineated, accessory cusp-like structure projecting from cingulum to the incisal edge of anterior teeth. This anomaly is rare in the mandibular dentition and rarer on the facial aspect. A case of this infrequent entity of mandibular facial talon cusp and its management is reported here. PMID:25298658
Yen, S L; Shang, W; Shuler, C; Yamashita, D D
Although distraction osteogenesis can lengthen congenitally small mandibles, the distraction procedure can be difficult to control. To study the efficacy and safety of orthodontic spring guidance on bilateral mandibular distraction, an 8-mm anterior open bite was experimentally produced and corrected during bilateral mandibular distraction in rabbits. Orthodontic springs were attached to the anterior maxilla and mandible to redirect an ongoing distraction procedure. Sixteen rabbits underwent mandibular distraction: 6 rabbits received heavy springs (8 oz), 6 rabbits received light force springs (2 oz), and 4 rabbits served as control animals with anterior open bites without spring guidance. Nickel-titanium springs were applied during the last week of osseous distraction and the first week of consolidation. Distractors were left in place throughout a 2-month consolidation period. None of the animals developed fibrous union as a result of spring guidance. The 8-mm open bite did not close in the control group or in the light spring group after 2 weeks of spring wear or during the consolidation period. Heavy springs completely closed the experimental open bites within 2 weeks (P <.01, analysis of variance). Bite corrections did not change during the consolidation period. This study indicated that the addition of an orthodontic spring to a mandibular distraction procedure did not impair bone healing. With the distraction device in place, heavy spring forces redirected an ongoing mandibular distraction procedure and corrected an open bite, distraction side effect. Direct measurements, radiographic measurements, and tissue histologic factors described changes in segment position and shape of the distraction site.
Ryu, Hyeong-Seok; An, Ki-Yong
Objective The purpose of this study was to assess rotational patterns of dentofacial structures according to different vertical skeletal patterns by cone-beam computed tomography (CBCT) and analyze their influence on menton deviation in skeletal Class III deformity with mandibular asymmetry. Methods The control group consisted of 30 young adults (15 men, 15 women) without any severe skeletal deformity. The asymmetry group included 55 adults (28 men, 27 women) with skeletal Class III deformity and at least 3-mm menton deviation from the midsagittal plane; it was divided into the hyperdivergent and hypodivergent subgroups using a mandibular plane angle cutoff of 35°. Fourteen rotational variables of the dental arches and mandible were measured and compared among the groups. Correlations between menton deviation and the other variables were evaluated. Results The asymmetry group showed significantly larger measurements of roll and yaw in the mandible than the control group. The hypodivergent subgroup showed significant differences in maxillary posterior measurements of yaw (p < 0.01) and maxillary anterior shift (p < 0.05) compared with the hyperdivergent subgroup. All the mandibular measurements had significant correlations with menton deviation (p < 0.01). Most measurements of roll were positively correlated with one another (p < 0.01). Measurements of yaw and roll in the posterior regions were also positively correlated (p < 0.05). Conclusions Menton deviation in skeletal Class III deformity with mandibular asymmetry is influenced by rotation of mandibular posterior dentofacial structures. The rotational patterns vary slightly according to the vertical skeletal pattern. PMID:26258061
Fregnani, Eduardo-Rodrigues; Leite, Amanda-Almeida; Parahyba, Claudia-Joffily; Nesrallah, Ana-Cristina-Alo; Ramos-Perez, Flávia-Maria-de Moraes
The occurrence of a mandibular lesion as the first sign of multiple myeloma (MM) is uncommon. This report describes a case of MM diagnosed because of a mandibular lesion. A 62-year-old woman presented a destructive radiolucent lesion in the right mandibular ramus. The lesion caused rupture of the anterior cortical bone and extended from the retromolar area to the coronoid process. An incisional biopsy was performed. Histopathological examination revealed numerous pleomorphic plasma cells, some with binucleated nuclei. The tumor cells showed kappa light-chain restriction. Bone marrow biopsy showed findings of massive infiltration of neoplastic plasma cells, besides lesions in the vertebrae. The diagnosis of MM was established. The patient underwent autologous hematopoietic stem-cell transplantation. Currently, the patient is under regular follow up after 40 months of initial treatment. In conclusion, MM should be considered in the differential diagnosis of destructive mandibular lesions. Key words:Mandible, multiple myeloma, radiolucent lesion. PMID:27703618
Rhone, Ariane E.; Nourski, Kirill V.; Kawasaki, Hiroto; Oya, Hiroyuki; Griffiths, Timothy D.; Howard, Matthew A.; Tranel, Daniel
Retrieving the names of friends, loved ones, and famous people is a fundamental human ability. This ability depends on the left anterior temporal lobe (ATL), where lesions can be associated with impaired naming of people regardless of modality (e.g., picture or voice). This finding has led to the idea that the left ATL is a modality-independent convergence region for proper naming. Hypotheses for how proper-name dispositions are organized within the left ATL include both a single modality-independent (heteromodal) convergence region and spatially discrete modality-dependent (unimodal) regions. Here we show direct electrophysiologic evidence that the left ATL is heteromodal for proper-name retrieval. Using intracranial recordings placed directly on the surface of the left ATL in human subjects, we demonstrate nearly identical responses to picture and voice stimuli of famous U.S. politicians during a naming task. Our results demonstrate convergent and robust large-scale neurophysiologic responses to picture and voice naming in the human left ATL. This finding supports the idea of heteromodal (i.e., transmodal) dispositions for proper naming in the left ATL. PMID:25632128
Wood, Lauren K.; Arruda, Ellen M.
The incidence of tendon degeneration and rupture increases with advancing age. The mechanisms underlying this increased risk remain unknown but may arise because of age-related changes in tendon mechanical properties and structure. Our purpose was to determine the effect of aging on tendon mechanical properties and collagen fibril morphology. Regional mechanical properties and collagen fibril characteristics were determined along the length of tibialis anterior (TA) tendons from adult (8- to 12-mo-old) and old (28- to 30-mo-old) mice. Tangent modulus of all regions along the tendons increased in old age, but the increase was substantially greater in the proximal region adjacent to the muscle than in the rest of the tendon. Overall end-to-end modulus increased with old age at maximum tendon strain (799 ± 157 vs. 1,419 ± 91 MPa) and at physiologically relevant strain (377 ± 137 vs. 798 ± 104 MPa). Despite the dramatic changes in tendon mechanical properties from adulthood to old age, collagen fibril morphology and packing fraction remained relatively constant in all tendon regions examined. Since tendon properties are influenced by their external loading environment, we also examined the effect of aging on TA muscle contractile properties. Maximum isometric force did not differ between the age groups. We conclude that TA tendons stiffen in a region-dependent manner throughout the life span, but the changes in mechanical properties are not accompanied by corresponding changes in collagen fibril morphology or force-generating capacity of the TA muscle. PMID:21737825
Charlton, S; Muir, L; Skinner, T C; Walters, L
Developmental Dysplasia of the Hip (DDH) is the most common notifiable musculoskeletal birth defect in South Australia (SA). Despite routine screening by physical examination of the hips in the neonatal period and at 6 weeks of age, the risk of late diagnosis is increased in rural areas. It is assumed this is due to the examining doctors' reduced clinical expertise. Introducing Anterior Dynamic Ultrasound (ADUS) has reduced the late detection rates in Sweden to almost zero, and may benefit Australian infants in rural areas if routine screening was introduced. This study reports on a small implementation pilot in a SA regional hospital where volunteer postnatal mothers consented to their babies having ADUS examinations. The pilot was evaluated by collecting results of physical examination, ADUS, and surveying parental impressions of the screening test. Hips of 86 infants underwent ADUS during the implementation pilot. Parents' perceptions were mainly very positive and indicated ADUS was an accessible and acceptable screening test. Of the hips scanned, three were found to have maximum movement of the femoral head of >3 mm and were deemed to demonstrate increased laxity. Four hips described as loose or mobile on clinical examination were found to be within normal limits of maximum mobility on ADUS. This study has demonstrated that a larger scale implementation project would be feasible in regional Australia, and would enable researchers to better understand how to reduce the late diagnosis rate of DDH in rural areas.
Turkyilmaz, I; Suarez, J C; Company, A M; McGlumphy, E A
Although immediate/early loading protocols for dental implants have presented encouraging outcomes, immediate loading procedures may cause discomfort to the patient and may increase the possibility of damage to the surgical site during the impression procedures. The aim of this study was to describe an alternative technique to fabricate a mandibular hybrid prosthesis in three or four days without making any final impression and to evaluate the outcomes of this technique. Seven patients aged 41 to 71 years (mean age, 58 +/- 11) were considered for this study. Each patient received five implants for the reconstruction of the edentulous mandible. These implants were placed in the anterior region of an edentulous mandible and restored with a final mandibular hybrid prosthesis in four days using the Ohio State University (OSU) acrylic frame requiring no final impression procedure. The patients were followed up to 19 months after implant placement. No implants were lost, no technical complications were observed and only minor marginal bone loss was noted after an average 15 months. This clinical study shows that the OSU acrylic frame, which can easily be customized and accommodates variability in arch form, may be an alternative method to restore any edentulous mandible with an early load mandibular hybrid prosthesis.
Buyukkaplan, US; Guldag, MU
Objectives Fluoride is one of the biological trace elements with a strong affinity for osseous, cartilaginous and dental tissue. The dental and skeletal effects of high fluoride intake have already been studied in the literature, but little is known about the effects of high fluoride intake on edentulous mandibles. The purpose of this study was to evaluate the effects of high fluoride intake on mandibular bone mineral density (BMD) measured by the dual-energy X-ray absorptiometry (DXA) technique in edentulous individuals with systemic fluorosis. Methods 32 people who were living in an endemic fluorosis area since birth and 31 people who were living in a non-endemic fluorosis area since birth (control group) participated in this study. Systemic fluorosis was diagnosed in the patients using the sialic acid (NANA)/glycosaminoglycan (GAG) ratio. The BMDs of the mandibles were determined by the DXA technique. Results The serum NANA/GAG ratios in the fluorosis group were significantly lower than those in the control group (p < 0.001). There was also a statistically significant difference in mandibular BMD measurements (p < 0.05) between the systemic fluorosis and control groups, as measured by the DXA technique. Mandibular body BMD measurements were higher in the fluorosis group (1.25 ± 0.24 g cm−2) than in the control group (1.01 ± 0.31 g cm−2). Conclusions The results of the study showed that fluoride intake higher than the optimum level causes increased mandibular BMD in edentulous individuals. Further dose-related studies are needed to determine the effects of high fluoride intake on bony structures of the stomatognathic system. PMID:22241885
RaviVarman, C.; Manoranjitham, R.; Veeramuthu, M.
The mandibular foramen is a landmark for procedures like inferior alveolar nerve block, mandibular implant treatment, and mandibular osteotomies. The present study was aimed to identify the precise location of the mandibular foramen and the incidence of accessory mandibular foramen in dry adult mandibles of South Indian population. The distance of mandibular foramen from the anterior border of the ramus, posterior border of the ramus, mandibular notch, base of the mandible, third molar, and apex of retromolar trigone was measured with a vernier caliper in 204 mandibles. The mean distance of mandibular foramen from the anterior border of ramus of mandible was 17.11±2.74 mm on the right side and 17.41±3.05 mm on the left side, from posterior border was 10.47±2.11 mm on the right side and 9.68±2.03 mm on the left side, from mandibular notch was 21.74±2.74 mm on the right side and 21.92±3.33 mm on the left side, from the base of the ramus was 22.33±3.32 mm on the right side and 25.35±4.5 mm on the left side, from the third molar tooth was 22.84±3.94 mm on the right side and 23.23±4.21 mm on the left side, from the apex of retromolar trigone was 12.27±12.13 mm on the right side and 12.13±2.35 mm on the left side. Accessory mandibular foramen was present in 32.36% of mandibles. Knowledge of location mandibular foramen is useful to the maxillofacial surgeons, oncologists and radiologists. PMID:28127498
Clinical and Radiographic Evaluation of a Small-Diameter Dental Implant Used for the Restoration of Patients with Permanent Tooth Agenesis (Hypodontia) in the Maxillary Lateral Incisor and Mandibular Incisor Regions: A 36-Month Follow-Up.
King, Paul; Maiorana, Carlo; Luthardt, Ralph G; Sondell, Katarina; Øland, Jesper; Galindo-Moreno, Pablo; Nilsson, Peter
For patients with narrow, single-tooth edentulous ridges as a result of permanent tooth agenesis (hypodontia) in the maxillary lateral and mandibular incisor regions, dental implant treatment may present a reliable and predictable restorative treatment solution. The aim of the present study was to evaluate the clinical reliability and outcome of small-diameter dental implants placed in a one-stage procedure with early loading replacing maxillary lateral or mandibular incisor teeth. Patients with hypodontia in the maxillary lateral incisor or mandibular incisor region analyzed in this report were selected from a larger prospective multicenter study. Small-diameter dental implants (AstraTech OsseoSpeed TX 3.0 S, Dentsply) of different lengths were placed using a one-stage surgical protocol with a 6- to 10-week healing period before loading. Probing pocket depth, bleeding on probing, and gingival zenith score were assessed after 6, 12, 24, and 36 months. Radiographic examination was assessed at 6, 12, and 36 months. In total, 38 patients were included in this analysis and 62 small-diameter implants were placed. The mean distance between adjacent teeth was 6.30 mm (SD: 1.36). All patients received a titanium transmucosal abutment and cement-retained ceramic crown after 6 to 10 weeks of healing. Two implants were lost during the healing period before loading, providing a total implant survival rate of 96.8%. No implant fractures were reported. Mean marginal bone level change from surgery to follow-up visits at 6, 12, and 36 months were 0.39 mm, 0.22 mm, and 0.23 mm, respectively. The condition of soft tissue was stable at all follow-up visits with clinically insignificant changes in probing depth, bleeding on probing, and gingival zenith score. This study evaluated the behavior over 36 months of AstraTech Osseospeed TX 3.0 S dental implants placed into narrow one-tooth defect edentulous ridges as a result of hypodontia. The data collected highlighted the stability of
Yap, Yan Lin; Lim, Jane; Ong, Wei Chen; Yeo, Matthew; Lee, Hanjing; Lim, Thiam Chye
The fibular free flap is the gold standard for mandibular reconstruction. Accurate 3-dimensional contouring and precise alignment of the fibula is critical for reestablishing native occlusion and facial symmetry. Following segmental mandibulectomy, the remaining mandibular fragments become freely mobile. Various stabilization methods including external fixation, intermaxillary fixation, and preplating with reconstruction plate have been used. We describe a modification to the preplating technique. After wide resection of buccal squamous cell carcinoma, our patient had an 11-cm mandibular defect from the angle of the left mandible to the right midparasymphyseal region. A single 2.0-mm Unilock® (Synthes, Singapore) plate was used to span the defect. This was placed on the vestibular aspect of the superior border of the mandibular remnants before resection. Segmental mandibulectomy was then performed with the plate removed. The spanning plate was then reattached to provide rigid fixation. The fibular bone was contoured with a single osteotomy and reattached. The conventional technique involves molding of the plate at the inferior border of the mandible. This is time-consuming and not possible in patients with distorted mandibular contour. It is also difficult to fit the osteotomized fibula to the contoured plate. In comparison, the superiorly positioned spanning plate achieve rigid fixation of the mandible while leaving the defect completely free and unhampered by hardware, allowing space for planning osteotomies and easier fixation of the neomandible. Using this modified technique, we are able to recreate the original mandibular profile with ease. PMID:23997856
Yap, Yan Lin; Lim, Jane; Ong, Wei Chen; Yeo, Matthew; Lee, Hanjing; Lim, Thiam Chye
The fibular free flap is the gold standard for mandibular reconstruction. Accurate 3-dimensional contouring and precise alignment of the fibula is critical for reestablishing native occlusion and facial symmetry. Following segmental mandibulectomy, the remaining mandibular fragments become freely mobile. Various stabilization methods including external fixation, intermaxillary fixation, and preplating with reconstruction plate have been used. We describe a modification to the preplating technique. After wide resection of buccal squamous cell carcinoma, our patient had an 11-cm mandibular defect from the angle of the left mandible to the right midparasymphyseal region. A single 2.0-mm Unilock® (Synthes, Singapore) plate was used to span the defect. This was placed on the vestibular aspect of the superior border of the mandibular remnants before resection. Segmental mandibulectomy was then performed with the plate removed. The spanning plate was then reattached to provide rigid fixation. The fibular bone was contoured with a single osteotomy and reattached. The conventional technique involves molding of the plate at the inferior border of the mandible. This is time-consuming and not possible in patients with distorted mandibular contour. It is also difficult to fit the osteotomized fibula to the contoured plate. In comparison, the superiorly positioned spanning plate achieve rigid fixation of the mandible while leaving the defect completely free and unhampered by hardware, allowing space for planning osteotomies and easier fixation of the neomandible. Using this modified technique, we are able to recreate the original mandibular profile with ease.
Audet, M A; Descarries, L; Doucet, G
The regional and laminar distribution of the serotonin (5-HT) innervation in adult rat cerebral cortex was quantified in radioautographs of semi-thin sections from whole hemisphere slices incubated with tritiated 5-HT and a monoamine oxidase inhibitor. Uptake-labelled axonal varicosities (aggregates of silver grains) were counted with the help of a computerized image analyser, in seven cytoarchitectonic areas of the anterior half of the cortex: Cg3, rostral AID, Cg2, Fr1, Par1, caudal AID and Pir (prepiriform). Since the average diameter of cortical 5-HT varicosities had been previously measured in electron microscope radioautographs, the counts of labelled sites per mm2 of radioautograph could be transformed to numbers of varicosities per mm3 of tissue after a double correction for incomplete detection at the chosen duration of radioautographic exposure and from the thickness of section examined. The mean regional density of cortical 5-HT innervation was thus evaluated at 5.8 million varicosities per mm3 of tissue, ranging from 4.4 (Cg2) to 7.1 million (AIDr). Cg2, Par1 and Fr1 showed significantly lower regional densities than Cg3, AIDc, Pir and AIDr. The highest laminar density was that of layer I in all regions except Pir, but each region had a distinct pattern of 5-HT innervation. In Par1, for example, there was a second band of predilection amounting to 5.3 million varicosities per mm3 at the height of layer Va. On the basis of these figures, it was possible to extrapolate the average number of cortical 5-HT varicosities per midbrain raphe nerve cell body of origin (500,000 at least), their average number per cortical target neuron (145-230), their incidence among all axon terminals in cortex (1/200), their mean endogenous amine content (0.045 fg), and their mean number per varicosity of recognition sites for reuptake blockers such as paroxetine, citalopram or cyanoimipramine (5000-6200). Such quantitative data and further correlations between 5-HT
Sagittal split osteotomy (SSO) is a surgical technique largely employed for mandibular mobilizations in orthognatic procedures. However, the traditional design of buccal osteotomy, located at the junction of mandibular ramus and body, may prevent more extensive sliding between the bone segments, particularly on the advance, laterality and verticality of the mandibular body. The author proposes a new technical and conceptual solution, in which osteotomy is performed in a more distal region, next to the mental formamen. Technically, the area of contact between medullary-cancellous bone surfaces is increased, resulting in larger sliding rates among bone segments; it also facilitates the use of rigid fixation systems, with miniplates and monocortical screws. Conceptually, it interferes with the resistance arm of the mandible, seen as an interpotent lever of the third gender. PMID:17355642
Flores, Roberto L.
Mandibular distraction has revolutionized the treatment of Robin sequence associated with severe airway obstruction. The distraction technique remains the only intervention that directly corrects mandibular hypoplasia and the retropositioned tongue, providing efficient relief of airway stenosis. Multiple studies have demonstrated the efficacy of distraction in avoiding tracheostomy and decreasing the severity airway obstruction in this patient population. The benefit to avoiding tracheostomy and relieving airway obstruction is superior to that of tongue–lip adhesion. It is, therefore, not surprising that mandibular distraction has become the first-line intervention at many centers for the surgical treatment of Robin sequence. The complication profile associated with mandibular distraction appears low; the most common complication is infection, which can be treated by antibiotics alone. The severity of airway obstruction can be quantified by polysomnogram: This tool has become one of the most widely used objective metrics in the Robin sequence population. Therefore indications for surgery, timing of palatoplasty and long-term assessment of airway function should be performed in conjunction with sleep study analysis. The effects of mandibular lengthening on feeding difficulty in Robin sequence patient remains a topic of controversy. Studies have demonstrated conflicting results: This can be an area of future study. Agreed-upon indications for surgery and definitive protocols of care have yet to be formulized; future research should focus on achieving these goals. Such studies would require agreed-upon terminology for Robin sequence, an increase in comparative and prospective analysis, and the use of quantifiable metrics of clinical results. PMID:25383055
Kumar, Batchu Pavan; Venkatesh, V; Kumar, K A Jeevan; Yadav, B Yashwanth; Mohan, S Ram
Mandibular reconstruction has changed significantly over the years and continues to evolve with the introduction of newer technologies and techniques. This article reviews the history of oromandibular reconstruction, biomechanics of mandible, summarizes the reconstruction options available for mandible with defect classification, goals in reconstruction, the various donor sites, current reconstructive options, dental rehabilitation and persistent associated problems. Oromandibular reconstruction, although a challenge for the head and neck reconstructive surgeon, is now reliable and highly successful with excellent long-term functional and aesthetic outcomes with the use of autogenous bone grafts and current reconstructive options. The ideal reconstruction would provide a solid arch to articulate with the upper jaw, restoring swallowing speech, mastication, and esthetics. Autogenous vascularized bone grafts in combination with microsurgical techniques have revolutionized mandibular reconstruction in oral cancer surgery. Current trends in mandibular reconstruction aim to achieve reestablishment of a viable mandible of proper form and maxillary mandibular relationship while decreasing the need for invasive autogenous graft procurement. However the optimal reconstruction of mandibular defects is still controversial in regards to reconstructive options which include the donor site selection, timing of surgery and method of reconstruction.
Flores, Roberto L
Mandibular distraction has revolutionized the treatment of Robin sequence associated with severe airway obstruction. The distraction technique remains the only intervention that directly corrects mandibular hypoplasia and the retropositioned tongue, providing efficient relief of airway stenosis. Multiple studies have demonstrated the efficacy of distraction in avoiding tracheostomy and decreasing the severity airway obstruction in this patient population. The benefit to avoiding tracheostomy and relieving airway obstruction is superior to that of tongue-lip adhesion. It is, therefore, not surprising that mandibular distraction has become the first-line intervention at many centers for the surgical treatment of Robin sequence. The complication profile associated with mandibular distraction appears low; the most common complication is infection, which can be treated by antibiotics alone. The severity of airway obstruction can be quantified by polysomnogram: This tool has become one of the most widely used objective metrics in the Robin sequence population. Therefore indications for surgery, timing of palatoplasty and long-term assessment of airway function should be performed in conjunction with sleep study analysis. The effects of mandibular lengthening on feeding difficulty in Robin sequence patient remains a topic of controversy. Studies have demonstrated conflicting results: This can be an area of future study. Agreed-upon indications for surgery and definitive protocols of care have yet to be formulized; future research should focus on achieving these goals. Such studies would require agreed-upon terminology for Robin sequence, an increase in comparative and prospective analysis, and the use of quantifiable metrics of clinical results.
Danto, Jay B
Integrated neuromusculoskeletal release (INR) using a segmental anterior/posterior approach is an osteopathic manipulative treatment technique that is easily learned and applied. The segmental anterior/posterior approach to INR was developed as a practical osteopathic manipulative treatment procedure for the inpatient setting, but also has equal efficacy in the outpatient setting. It builds on the principles of INR and myofascial release techniques, as well as other techniques. This approach focuses on both the anterior and posterior connectivity of the body through the neuromusculoskeletal system and uses this connectivity to effectively treat somatic dysfunctions. The principles of INR are discussed, as well as the role of INR in the diagnosis and treatment of somatic dysfunctions in the thoracic, lumbar, and sacral regions.
Weinberg, L A
A deflective slide in centric relation to centric occlusion does not necessarily mean anterior condylar displacement. Its diagnosis and treatment depend on the correlation of three factors: the direction and magnitude of the mandibular slide from centric relation to centric occlusion, the change in vertical dimension of occlusion during the slide, and the position of the condyles in the fossae when the teeth are in the maximum occlusion (centric occlusion). When the change in vertical dimension almost equals to amount of slide from the deflective contact in centric relation to maximum intercuspation, very little anterior condylar displacement would be expected. Conversely, with proportionately little change in vertical dimension, more anterior condylar translation is required for a given degree of anterior slide. Examples of each type of anterior slide were related to the TMJ radiographs of the condylar position. If the direction and magnitude of the deflective occlusal contact can be correlated with the TMJ radiographs, the centric relation is "functional,'' and the clinically retruded mandibular position should be used. When this correlation does not exist, the centric relation is "dysfunctional'' and the terminal hinge position (retruded mandibular position) should not be used for restorative or corrective procedures. Examples of anterior condylar displacement were given, including deviation, with a comparison of "before'' and "after'' TMJ radiographs.
Ehsani, Sara; Mirhashemi, Fatemeh Sadat; Asgary, Saeed
Introduction Mandibular first molar is the most important tooth with complicated morphology. In finite element (FE) studies, investigators usually prefer to model anterior teeth with a simple and single straight root; it makes the results deviate from the actual case. The most complicated and time-consuming step in FE studies is modeling of the desired tooth, thus this study was performed to establish a finite element method (FEM) of reconstructing a mandibular first molar with the greatest precision. Materials and Methods An extracted mandibular first molar was digitized, and then radiographed from different aspects to achieve its outer and inner morphology. The solid model of tooth and root canals were constructed according to this data as well as the anatomy of mandibular first molar described in the literature. Result A three-dimensional model of mandibular first molar was created, giving special consideration to shape and root canal system dimensions. Conclusion This model may constitute a basis for investigating the effect of different clinical situations on mandibular first molars in vitro, especially on its root canal system. The method described here seems feasible and reasonably precise foundation for investigations. PMID:23717327
Maras, Pamela M.; Petrulis, Aras
In many rodent species, such as Syrian hamsters, reproductive behavior requires neural integration of chemosensory information and steroid hormone cues. The medial amygdala processes both of these signals through anatomically distinct sub-regions; the anterior region (MeA) receives substantial chemosensory input, but contains few steroid receptor-labeled neurons, whereas the posterodorsal region (MePD) receives less chemosensory input, but contains dense populations of androgen and estrogen receptors. Importantly, these sub-regions have considerable reciprocal connections, and previous studies in our lab have shown that functional interactions between MeA and MePD are required for the preference to investigate opposite-sex odors in male hamsters. We therefore hypothesized that chemosensory and hormone signals are conveyed directly between MeA and MePD. To test this hypothesis, we injected the retrograde tracer, cholera toxin B (CTB), into either MeA or MePD of male subjects and identified whether retrogradely labeled cells within MePD or MeA, respectively, expressed (1) Fos protein following exposure to female or male odors or (2) androgen receptors (AR). Approximately 36% of CTB-labeled cells within MeA (that project to MePD) also expressed Fos following exposure to either social odor, compared to the only 13% of CTB-labeled cells within MePD (that project to MeA) that also expressed odor-induced Fos. In contrast, 57% of CTB-labeled cells within MePD also contained AR, compared to the 28% of CTB-labeled cells within MeA that were double-labeled for AR/CTB. These results provide the first anatomical evidence that chemosensory and hormone cues are conveyed directly between MeA and MePD. Furthermore, these data suggest that chemosensory information is conveyed primarily from MeA to MePD, whereas hormone information is conveyed primarily from MePD to MeA. More broadly, the interactions between MeA and MePD may represent a basic mechanism by which the brain integrates
Chim, Harvey; Salgado, Christopher J.; Mardini, Samir; Chen, Hung-Chi
Defects requiring reconstruction in the mandible are commonly encountered and may result from resection of benign or malignant lesions, trauma, or osteoradionecrosis. Mandibular defects can be classified according to location and extent, as well as involvement of mucosa, skin, and tongue. Vascularized bone flaps, in general, provide the best functional and aesthetic outcome, with the fibula flap remaining the gold standard for mandible reconstruction. In this review, we discuss classification and approach to reconstruction of mandibular defects. We also elaborate upon four commonly used free osteocutaneous flaps, inclusive of fibula, iliac crest, scapula, and radial forearm. Finally, we discuss indications and use of osseointegrated implants as well as recent advances in mandibular reconstruction. PMID:22550439
Zweig, Barry E
Before any definitive treatment of mandibular fractures, the patient needs to be evaluated for more potentially life-threatening injuries. Complications can and do occur with treatment of mandibular fractures and can occur during any of the phases of treatment. The development of an accurate diagnosis and appropriate treatment plan is vital in achieving optimal success and decreasing complications. Knowledge of the anatomy and the principles of bone healing is also an important factor in preventing complications. To limit long-term untoward effects, complications should be recognized early and the appropriate treatment should be started before a minor complication becomes a complex one that is more difficult to manage.
Guttikonda, Leela Krishna; Nadella, Koteswara Rao; Uppaluru, Vijayalakshmi; Kodali, Rama Mohan; Nallamothu, Ranganadh
Median cleft of lower lip and mandible is a rare congenital anomaly described as cleft number 30 of Tessier's classification. In minor forms only lower lip cleft is seen. We report the case of a patient with median cleft of lower lip, severe ankyloglossia, cleft of mandibular symphysis, and residual cleft involving on right soft palate and associated with other facial clefts. These deformities were corrected in multiple stage procedure, consisting of release of the tongue from floor of the mouth and lower alveolus and fixation of the mandibular cleft done with right iliac bone graft using stainless steel miniplate. PMID:24711928
Traditional Postextractive Implant Site Preparation Compared with Pre-extractive Interradicular Implant Bed Preparation in the Mandibular Molar Region, Using an Ultrasonic Device: A Randomized Pilot Study.
The immediate placement of single postextractive implants is increasing in the everyday clinical practice. Due to insufficient bone tissue volume, proper primary stability, essential for subsequent osseointegration, is sometimes not reached. The aim of this work was to compare two different approaches: implant bed preparation before and after root extraction. Twenty-two patients of both sexes were selected who needed an implant-prosthetic rehabilitation of the fractured first mandibular molar or presented an untreatable endodontic pathology. The sites were randomly assigned to the test group (treated with implant bed preparation before molar extractions) or control group (treated with implant bed preparation after molar extractions) by a computer-generated table. All implants were placed by the same operator, who was experienced in both traditional and ultrasonic techniques. The implant stability quotient (ISQ) and the position of the implant were evaluated. Statistical analysis was carried out. In the control group, three implants were placed in the central portion of the bone septum, while eight implants were placed with a tilted axis in relation to the septum; in the test group, all implants were placed in ideal positions within the root extraction sockets. The different position of the implants between the two procedures was statistically significant. This work presented an innovative approach for implant placement at the time of mandibular molar extraction. Preparing the implant bed with an ultrasonic device before root extraction is a simple technique and also allows greater stability to be reached in a selective case.
Mehta, Sonya; Inoue, Kayo; Rudrauf, David; Damasio, Hanna; Tranel, Daniel; Grabowski, Thomas
Lesion-deficit studies support the hypothesis that the left anterior temporal lobe (ATL) plays a critical role in retrieving names of concrete entities. They further suggest that different regions of the left ATL process different conceptual categories. Here we test the specificity of these relationships and whether the anatomical segregation is related to the underlying organization of white matter connections. We reanalyzed data from a previous lesion study of naming and recognition across five categories of concrete entities. In voxelwise logistic regressions of lesion-deficit associations, we formally incorporated measures of disconnection of long-range association fiber tracts (FTs) and covaried for recognition and non-category specific naming deficits. We also performed fiber tractwise analyses to assess whether damage to specific FTs was preferentially associated with category-selective naming deficits. Damage to the basolateral ATL was associated with naming deficits for both unique (famous faces) and non-unique entities, whereas the damage to the temporal pole was associated with naming deficits for unique entities only. This segregation pattern remained after accounting for comorbid recognition deficits or naming deficits in other categories. The tractwise analyses showed that damage to the uncinate fasciculus was associated with naming impairments for unique entities, while damage to the inferior longitudinal fasciculus was associated with naming impairments for non-unique entities. Covarying for FT transection in voxelwise analyses rendered the cortical association for unique entities more focal. These results are consistent with the partial segregation of brain system support for name retrieval of unique and non-unique entities at both the level of cortical components and underlying white matter fiber bundles. Our study reconciles theoretic accounts of the functional organization of the left ATL by revealing both category-related processing and
Zhou, Lin; Li, Wei-ran
To investigate the alveolar bone defects of anterior alveolar bone in patients with bimaxillary protrusion by using cone-beam computed tomography (CBCT). The samples consisted of 50 patients with bimaxillary protrusion, who were assigned to the teenage group[20 cases, (13.1±1.0) years] and adult group[30 cases, (22.9±4.2) years]. The adult group included 9 hypo-divergent, 11 normo-divergent and 10 hyper-divergent patients. The images were obtained by using NewTom VG CBCT and the alveolar defects were evaluated. The ratio of the patients had alveolar bone defects was 94.00%. Meanwhile, the defects were associated with 38.60% of all the teeth. Most defects occurred on labial alveolar bone (98.66%); fenestration was found more in the maxillary alveolar region and dehiscence occurred more in the mandible. The dehiscences (3.06%) and defects prevalence (30.13%) of the teenage group were significant lower than those of the adult group (11.73% vs. 42.46%), P<0.05; while there was no significance of the fenestrations prevalence between the two group (P>0.05). The hypo-divergent group had lower fenestrations prevalence (22.22%) than the normo-divergent (33.84%) and hyper-divergent groups (37.50%), P<0.05. The upper central incisor had the lowest alveolar bone defect prevalence. Alveolar bone defects are common findings in patients with bimaxillary protrusion before orthodontic treatment. The prevalence of defects is affected by age and vertical-growth type.
Scolozzi, Paolo; Lombardi, Tommaso; Edney, Timothy; Jaques, Bertrand
Osteomyelitis of the mandible is a relatively rare inflammatory disease that usually stems from the odontogenic polymicrobial flora of the oral cavity. We are reporting 2 unusual cases of mandibular osteomyelitis resulting from enteric bacteria infection. In one patient, abundant clinical evidence suggested a diagnosis of a chronic factitious disease, whereas in the second patient no obvious etiology was found.
Dimeff, J.; Rositano, S.; Taylor, R. C.
Mandibular motion along three axes is measured by three motion transducers on floating yoke that rests against mandible. System includes electronics to provide variety of outputs for data display and processing. Head frame is strapped to test subject's skull to provide fixed point of reference for transducers.
Dimeff, J.; Rositano, S.; Taylor, R. C.
Mandibular motion along three axes is measured by three motion transducers on floating yoke that rests against mandible. System includes electronics to provide variety of outputs for data display and processing. Head frame is strapped to test subject's skull to provide fixed point of reference for transducers.
Celebi, Nukhet; Rohner, E. Carlos; Gateno, Jaime; Noble, Philip C.; Ismaily, Sabir K.; Teichgraeber, John F.; Xia, James J.
Purpose The purpose of this study was to develop a motion simulator capable of recreating and recording the full range of mandibular motions in a cadaveric preparation for an intact temporomandibular joint (TMJ) and after total joint replacement. Material and Methods A human cadaver head was used. Two sets of tracking balls were attached to the forehead and mandible, respectively. Computed tomographic (CT) scan was performed and 3-dimensional CT models of the skull were generated. The cadaver head was then dissected to attach the muscle activation cables and mounted onto the TMJ simulator. Realistic jaw motions were generated through the application of the following muscle forces: lateral pterygoid muscle, suprahyoid depressors (geniohyoid, mylohyoid, and digastric muscles), and elevator muscles. To simulate muscle contraction, cables were inserted into the mandible at the center area of each muscle's attachment. To provide a minimum mouth closing force at the initial position, the elevator muscles were combined at the anterior mandible. During mandibular movement, each motion was recorded using a high-resolution laser scanner. The right TMJ of the same head was reconstructed with a total TMJ prosthesis. The same forces were applied and the jaw motions were recorded again. CT scan was performed and 3-dimensional CT models of the skull with TMJ prosthesis were generated. Results Mandibular motions, before and after TMJ replacement, with and without lateral pterygoid muscle reattachment, were re-created in a cadaveric preparation. The laser-scanned data during the mandibular motion were used to drive 3-dimensional CT models. A movie for each mandibular motion was subsequently created for motion path analysis. Compared with mandibular motion before TMJ replacement, mandibular lateral and protrusive motions after TMJ replacement, with and without lateral pterygoid muscle reattachment, were greatly limited. The jaw motion recorded before total joint replacement was
Zawawi, Khalid H.
Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic treatment of adult patients to meet their esthetic demands. In this case report, a case of Class I malocclusion was treated with mandibular incisor extraction using the Invisalign appliance system. Successful tooth alignment of both arches was achieved. The use of Invisalign appliance is an effective treatment option in adult patients with Class I malocclusion that requires incisor extraction due to moderate to severe mandibular anterior crowding. PMID:25024852
Zawawi, Khalid H
Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic treatment of adult patients to meet their esthetic demands. In this case report, a case of Class I malocclusion was treated with mandibular incisor extraction using the Invisalign appliance system. Successful tooth alignment of both arches was achieved. The use of Invisalign appliance is an effective treatment option in adult patients with Class I malocclusion that requires incisor extraction due to moderate to severe mandibular anterior crowding.
Waingade, Manjushri; Gawande, Pushkar; Aditya, Amita; Medikeri, Raghavendra S
Pindborg tumor/Calcifying Epithelial Odontogenic Tumor (CEOT) is a benign epithelial odontogenic tumor which shows locally aggressive behavior and accounts for less than 1% of all odontogenic tumors. The most frequent location is the mandibular premolar and molar area; less frequently the lesion is found in the maxilla. Since histopathology remains the main method for definitive diagnosis, this lesion presents an enigma to a clinician when lesions occur in atypical locations. The authors report a case of CEOT in the maxillary anterior region associated with an impacted supernumerary tooth (mesiodens).
de Assis Ribeiro Carvalho, Felipe; Cevidanes, Lucia Helena Soares; Motta, Alexandre Trindade Simões da; de Oliveira Almeida, Marco Antonio; Phillips, Ceib
Introduction This prospective observational study evaluated changes in the 3-dimensional position and remodeling of the mandibular rami, condyles, and chin at splint removal and 1 year after mandibular advancement surgery. Methods Presurgery, splint removal (4–6 weeks postsurgery), and 1-year postsurgery cone-beam computed tomography scans of 27 subjects were used. Superimposition on the cranial base was used to assess positional or remodeling changes in the anatomic regions of interest. Surface distance displacements were visually displayed and quantified by 3-dimensional color maps. A 1-sample t test was used to assess the average postsurgical changes of each region of interest. The level of significance was set at 0.05. Results After antero-inferior chin displacement with surgery (mean, 6.81 ± 3.2 mm at splint removal), the average 1-year post-surgery displacement was not statistically significant (P = 0.44). Postsurgical adaptations greater than 2 mm were observed in 48% of the patients: 16% with an additional anterior-inferior displacement of the chin of 2 to 4 mm, and 4% with ≥4 mm; 20% had postero-superior movement of 2 to 4 mm, and 8% had postero-superior movement of ≥4 mm. The condyles tended to move, on average, ≤2 mm supero-posteriorly with surgery, and this small positional displacement was maintained 1 year postsurgery (right condyle, P = 0.58; left, P = 0.88). The rami exhibited outward (lateral) movements with surgery, with greater displacement of the inferior part of the rami (≥2 mm in 65% of the subjects). This torque of the ramus with surgery was stable 1 year postsurgery. Conclusions Three-dimensional assessment of skeletal changes with mandibular advancement surgery shows that nearly half of the patients have >2 mm change in chin position from splint removal to the 1-year follow-up, with approximately equal chances of anterior and posterior movement. Torque of the rami usually occurs with mandibular advancement surgery. PMID:20381760
Zhou, Shuncheng; Yan, Juanjuan; Da, Hu; Yang, Yang; Wang, Na; Wang, Wenyong; Ding, Yin; Sun, Shiyao
Previous studies have confirmed that patients with mandibular deviation often have abnormal morphology of their cervical vertebrae. However, the relationship between mandibular deviation, scoliosis, and trunk balance has not been studied. Currently, mandibular deviation is usually treated as a single pathology, which leads to poor clinical efficiency. We investigated the relationship of spine coronal morphology and trunk balance in adult patients with mandibular deviation, and compared the finding to those in healthy volunteers. 35 adult patients with skeletal mandibular deviation and 10 healthy volunteers underwent anterior X-ray films of the head and posteroanterior X-ray films of the spine. Landmarks and lines were drawn and measured on these films. The axis distance method was used to measure the degree of scoliosis and the balance angle method was used to measure trunk balance. The relationship of mandibular deviation, spine coronal morphology and trunk balance was evaluated with the Pearson correlation method. The spine coronal morphology of patients with mandibular deviation demonstrated an "S" type curve, while a straight line parallel with the gravity line was found in the control group (significant difference, p<0.01). The trunk balance of patients with mandibular deviation was disturbed (imbalance angle >1°), while the control group had a normal trunk balance (imbalance angle <1°). There was a significant difference between the two groups (p<0.01). The degree of scoliosis and shoulder imbalance correlated with the degree of mandibular deviation, and presented a linear trend. The direction of mandibular deviation was the same as that of the lateral bending of thoracolumbar vertebrae, which was opposite to the direction of lateral bending of cervical vertebrae. Our study shows the degree of mandibular deviation has a high correlation with the degree of scoliosis and trunk imbalance, all the three deformities should be clinically evaluated in the
Nart, Jose; Valles, Cristina
There is limited evidence regarding the effect of the subepithelial connective tissue graft (SCTG) on root coverage in the mandibular anterior region. A sample of 15 Miller Class II and III recessions were treated in 15 patients using a SCTG with a tunnel technique. After a mean follow-up of 20.53 months, the mean percentage of root coverage was 83.25% for all treated recessions. Furthermore, a statistically significant increase of keratinized tissue was observed at the end of the evaluation period (2.66 mm; P = .001). The combination of tunnel technique and SCTG should be considered a treatment option to obtain root coverage in mandibular incisors with Class II and III recession defects.
Hsu, Kuang-Wei; Shen, Yu-Fu
The prevalence of hypodontia is reported to be between 1.5% to 10% in the permanent dentition. In the anterior teeth, maxillary lateral incisors and mandibular central incisors are the most frequently involved teeth. This causes esthetic problems for the patient. Several reports have focused on restoration of retained maxillary primary anterior teeth, but none have described restoration of retained mandibular primary incisors. This clinical report describes the restoration of infra-occluded retained primary mandibular central incisors of a 17 year-old girl diagnosed with hypodontia. All-ceramic crowns made with computer-aided design/ computer-aided manufacturing technology were used to restore the teeth incisally and interproximally. Due to a relatively short root length and inadequate crown-root ratio, the primary mandibular central incisors were splinted and adjusted to distribute the protrusive force evenly across the maxillary and mandibular incisors. Functional and esthetic results were achieved.
Harper, R P; de Bruin, H; Burcea, I
The masticatory muscles function as a unit during precise mandibular positioning movements that occur during such activities as speech, singing, or playing musical instruments. This investigation was designed to assess jaw muscle recruitment patterns during controlled mandibular movement in normal subjects and in patients with mandibular retrognathism. A computer-integrated electromyography (EMG) and movement monitoring (Selspot) system was used to collect data over 7 seconds of a sagittal border movement (Posselt envelope) of the mandible and 4 seconds each of rest position, light tooth contact, and maximum clench. Fine wire bipolar electrodes were placed into the inferior belly of the lateral pterygoid muscles bilaterally and surface electrodes were placed bilaterally over the anterior belly of the temporalis muscles and the masseter muscles. Ten subjects with Class I occlusion, normal cephalometric values, and an absence of temporomandibular joint (TMJ) dysfunction were compared with 12 patients with mandibular retrognathism, Class II malocclusion, and an absence of clinical signs of TMJ internal derangement before and after a bilateral sagittal split and advancement of the mandible. There was a wide variation in standard deviations of EMG activity for the lateral pterygoid muscles in the retrognathic patients compared with normal controls before surgery (P < .05). In light tooth contact, temporalis muscle activity increased after surgery with respect to both control and the presurgical levels (P < .05, P < .005, respectively). In maximum clench, activity in all muscle groups in the retrognathic patients, both before and after surgery, were below that of control subjects (P < .005). The lateral pterygoid muscles showed late recruitment, with low EMG activity levels during the forward movement phase of the envelope, before surgery compared with controls (P < .001). After surgery, the lateral pterygoid muscle showed early recruitment in the forward movement
Kleber, Boris; Friberg, Anders; Zeitouni, Anthony; Zatorre, Robert
Previous studies on vocal motor production in singing suggest that the right anterior insula (AI) plays a role in experience-dependent modulation of feedback integration. Specifically, when somatosensory input was reduced via anesthesia of the vocal fold mucosa, right AI activity was down regulated in trained singers. In the current fMRI study, we examined how masking of auditory feedback affects pitch-matching accuracy and corresponding brain activity in the same participants. We found that pitch-matching accuracy was unaffected by masking in trained singers yet declined in nonsingers. The corresponding brain region with the most differential and interesting activation pattern was the right AI, which was up regulated during masking in singers but down regulated in nonsingers. Likewise, its functional connectivity with inferior parietal, frontal, and voice-relevant sensorimotor areas was increased in singers yet decreased in nonsingers. These results indicate that singers relied more on somatosensory feedback, whereas nonsingers depended more critically on auditory feedback. When comparing auditory vs somatosensory feedback involvement, the right anterior insula emerged as the only region for correcting intended vocal output by modulating what is heard or felt as a function of singing experience. We propose the right anterior insula as a key node in the brain's singing network for the integration of signals of salience across multiple sensory and cognitive domains to guide vocal behavior.
Khan, Ahmed; Fareed, Wamiq Musheer; Tandon, Parul; Zafar, Muhammad Sohail
Temporomandibular joint ankylosis, a debilitating disease mainly affecting children, is characterized by progressive restriction of mouth opening and maxilla-mandibular developmental deformities. Craniofacial distraction osteogenesis has been developed as a standard surgical strategy for rectification of craniofacial deformities. The purpose of this study was to assess mono-planar distraction devices for the correction of various mandibular asymmetries in patients with unilateral temporomandibular joint ankylosis who developed restricted mouth opening and mandibular retrognathia. All patients were treated using one-stage distraction osteogenesis followed by temporalis fascia interpositional arthroplasty under general anesthesia. A significant increase in mandibular ramus and base length was observed. Although an increase in anterior lower facial height was observed, it was not significant statistically. A decrease in posterior lower facial height and corpus was observed. Oblique distraction with angular osteotomy allowed lengthening of both the ramus and corpus, yielding satisfactory results and hence eliminating the need of secondary surgery. In conclusion, univector internal distractors are effective for correction of multi-planar mandibular deficiencies by optimizing its placement through meticulous planning.
Baumrind, S; Bravo, L A; Ben-Bassat, Y; Curry, S; Korn, E L
The purpose of this study was to quantify the amount of alveolar modeling at the apices of the mandibular incisor and first molar specifically associated with appositional and resorptive changes on the lower border of the mandible during growth and treatment. Cephalometric data from superimpositions on anterior cranial base, mandibular implants of the Björk type, and anatomical "best fit" of mandibular border structures were integrated using a recently developed strategy, which is described. Data were available at annual intervals between 8.5 and 15.5 years for a previously described sample of approximately 30 children with implants. The average magnitudes of the changes at the root apices of the mandibular first molar and central incisor associated with modeling/remodeling of the mandibular border and symphysis were unexpectedly small. At the molar apex, mean values approximated zero in both anteroposterior and vertical directions. At the incisor apex, mean values approximated zero in the anteroposterior direction and averaged less than 0.15 mm/year in the vertical direction. Standard deviations were roughly equal for the molar and the incisor in both the anteroposterior and vertical directions. Dental displacement associated with surface modeling plays a smaller role in final tooth position in the mandible than in the maxilla. It may also be reasonably inferred that anatomical best-fit superimpositions made in the absence of implants give a more complete picture of hard tissue turnover in the mandible than they do in the maxilla.
reduce the fracture, i.e. re-align the fragments to prevent the loss of vertical dimension occurring with fracture and dislocation. Another goal is...with some permanent loss of vertical dimension and mandibular length.2 9 Dental Adaptations. With loss of posterior vertical dimension of the ramus...fracture in an adult, loss of posterior vertical dimension results in an anterior open-bite until "training of the musculature" by interocclusal elastics
Satpathy, Shouvanik; Dam, Aniruddha; Hossain, Mollah Arafat; Chatterjee, Jayanta
Surgical removal of benign tumors of the Parapharyngeal space (PPS) is the treatment of choice. PPS tumors may remain undetected for long periods of time and large tumors in the PPS can extend into the Retropharyngeal Space or into the Infra-Temporal Fossa. Anatomically, the mandible represents a significant obstacle to successful PPS surgery. Except for very small tumors, it is difficult to remove larger tumors from this region without some form of mandibular retraction. The standard mandibular "swing" approach involves splitting of the lower lip and a single parasymphysis osteotomy for retraction of the mandible laterally to expose the PPS. However, the morbidity associated with midline lip split and anesthesia of the hemi-labial region caused by the severing of the mental nerve is an unwanted complication of this approach. In this article, we describe an easier double mandibular osteotomy (Segmental Mandibular Swing Approach) which avoids the morbidity associated with lip splitting or intra-oral mucosal incision but allows excellent exposure of the superior and lateral aspect of PPS for easier removal of large tumors in this region.
Peñarrocha-Diago, Miguel; Pradíes, Guillermo; Sola-Ruiz, María-Fernanda; Agustín-Panadero, Rubén
Objectives: The aim of this study was to evaluate the survival and compare the appearance of different mechanical and biological complications, in screw-retained and cemented-retained single-tooth implant-supported restorations localized in the molar mandibular region, over a period of 1 to 4 years. Material and Methods: A retrospective study was carried out with a total of eighty implant-supported restorations, which were placed in eighty patients for prosthetic rehabilitation of a mandibular molar. Forty patients were rehabilitated with a cemented-retained restoration and the other forty with a screw-retained restoration. The presence of the following complications was recorded for both types of prostheses: Fractures of the ceramic veneering, loosening screws, mucositis and peri-implantitis. Debonding of the restoration was analyzed in the cemented-retained restoration group. The clinical survival of crowns was analyzed with a Kaplan-Meier test and the clinical complications were compared, using a Student t test and Log-rank test. Results: 27 patients registered some complication. The average rate of complications was 37,5% for cemented-retained restorations and 30% for screw-retained restorations. The complications more common in the cemented-retained restoration were the presence of mucositis (14,87%), while in the screw-retained restorations was the loosening screw (20%). Student t test and Log-Rank test found significant differences (p=0,001) between the screw loosening and presence of mucositis. Conclusions: The cemented-retained restorations seem to prevent screw loosening, but the presence of cement seem to increase the complications around the soft tissues, however in the screw-retained restorations the presence of mucositis and peri-implantitis are lower than cemented-retained restorations. The incidence of fracture of ceramic veneering was similar in both groups. Key words:Screw-retained restorations, cemented-retained restorations, screw loosening
de Blieux, D.D.; Baumrind, M.R.; Simons, E.L.; Chatrath, P.S.; Meyer, G.E.; Attia, Y.S.
An internal mandibular fenestra and chamber are found in many fossil hyracoids. The internal mandibular fenestra is located on the lingual surface of the mandibular corpus and opens into a chamber within the mandible. The mandibular chamber is maximally developed in late Eocene Thyrohyrax meyeri and early Oligocene Thyrohyrax domorictus from the Fayum Province of Egypt. The function of this chamber is unknown as it is not found in extant hyraxes, nor is it known to occur in any other mammal. In Thyrohyrax, this feature appears to be sexually dimorphic because it is confined to roughly one half of the specimens that otherwise cannot be separated by dental characteristics or measurements. It has been suggested that the chamber is found in females based on the presumed distribution of this character in other fossil hyracoids. Fossils from Fayum Quarry L-41, preserving the sexually dimorphic anterior dentition, show that, in Thyrohyrax meyeri and Thyrohyrax domorictus, the internal mandibular chamber is found in males. In Thyrohyrax litholagus, an internal mandibular fenestra and inflated mandibular chamber occurs in males whereas females show the variable presence of an internal mandibular fossa or fenestra but lack an expanded chamber. Other genera show differing patterns of sexual variation in which some Fayum hyracoids have an internal mandibular fenestra in both sexes but with the greatest development of the mandibular chamber occurring in males. We review functions proposed for the internal mandibular chamber and suggest that it housed a laryngeal air sac that may have had a vocal function by acting as a resonating chamber. ?? 2006 by the Society of Vertebrate Paleontology.
Tan, Keson Beng Choon
This report describes the clinical and technical aspects in the oral rehabilitation of an edentulous patient with knife-edge ridge at the mandibular anterior edentulous region, using implant-retained overdentures. The application of computer-aided design and computer-aided manufacturing (CAD/CAM) in the fabrication of the overdenture framework simplifies the laboratory process of the implant prostheses. The Nobel Procera CAD/CAM System was utilised to produce a lightweight titanium overdenture bar with locator attachments. It is proposed that the digital workflow of CAD/CAM milled implant overdenture bar allows us to avoid numerous technical steps and possibility of casting errors involved in the conventional casting of such bars. PMID:28396807
Goo, Chui Ling; Tan, Keson Beng Choon
This report describes the clinical and technical aspects in the oral rehabilitation of an edentulous patient with knife-edge ridge at the mandibular anterior edentulous region, using implant-retained overdentures. The application of computer-aided design and computer-aided manufacturing (CAD/CAM) in the fabrication of the overdenture framework simplifies the laboratory process of the implant prostheses. The Nobel Procera CAD/CAM System was utilised to produce a lightweight titanium overdenture bar with locator attachments. It is proposed that the digital workflow of CAD/CAM milled implant overdenture bar allows us to avoid numerous technical steps and possibility of casting errors involved in the conventional casting of such bars.
Créton, Marijn; Geraets, Wil; Verhoeven, Jan Willem; van der Stelt, Paul F; Verhey, Hans; Cune, Marco
Radiographic parameters of mandibular trabecular bone structure between 67 subjects having hypodontia and those without were studied on digital panoramic radiographs. Three regions of interest (ROI) were defined: the ascending ramus, apical of the mandibular molar and mesial of the first mandibular molar. The effects of the presence of hypodontia and the ROI on the mandibular trabecular bone structure were tested for statistical significance by means of multivariate analysis. Radiographic parameters of trabecular bone architecture were found to differ between various regions of the mandible (p = 0.000), but not between the group of hypodontia subjects and their controls (p = 0.23). There was no interaction effect between the ROIs and the two groups (p = 0.79). For people having hypodontia, some directional parameters of trabecular bone have a reverse correlation with the number of missing teeth. The fractal dimension and the number and perimeter of white segments in the binarized image correlate positively with the number of congenitally missing teeth. A limited number of parameters of radiographic mandibular trabecular bone structure correlate with the number of missing teeth. However, a markable difference in radiographic parameters of mandibular trabecular bone structure between hypodontia and non-hypodontia subjects could not be demonstrated. © 2009 Wiley Periodicals, Inc.
Torrie, Arissa; Sharma, Jyoti; Mason, Mark; Cruz Eng, Hillenn
BACKGROUND Acute compartment syndrome (ACS) of the thigh after elective primary total knee arthroplasty is rare. If not recognized and treated promptly, devastating consequences may result. Certain regional anesthesia techniques are thought to mask the symptoms of acute compartment syndrome, but there are no cases reported of adductor canal catheters masking the symptoms of thigh compartment syndrome. We report a case where symptoms and diagnosis of acute anterior thigh compartment syndrome were not masked by a functioning adductor canal catheter. CASE REPORT A 56-year-old male developed anterior thigh compartment syndrome after an elective primary total knee arthroplasty. Surgery was performed under spinal anesthesia with periarticular local infiltration analgesia. Postoperatively, an adductor canal catheter was placed, atraumatically, under ultrasound guidance in the recovery room with a plan to begin a continuous infusion of 0.2% ropivacaine 10 hours after the periarticular injection. Six hours after surgery, the patient complained of tightness and 10/10 pain in his right thigh, which was initially managed with parenteral opioids with moderate success. Continuous infusion through the adductor canal catheter was started and pain improved to 6/10 aching pain. Nonetheless, two hours after starting the continuous infusion, the patient reported tightness, swelling, and 10/10 pressure-like pain that was not relieved by the peripheral catheter infusion or PRN boluses of additional opioids. Due to the patient's symptomatology compartment pressures were measured. The anterior compartment pressure was 47 mm Hg and emergent anterior compartment fasciotomy was performed. CONCLUSIONS In this case, a functioning adductor canal catheter did not mask symptoms of, or delay diagnosis of, acute compartment syndrome in the thigh.
Bölükbaşı, Nilüfer; Yeniyol, Sinem
Resorption following tooth loss and poor bone quality affect the success of implants in the anterior maxilla. Inappropriate planning can cause implant loss and aesthetics problems that are difficult to resolve. There is a limited literature on the optimum number and location of implants in anterior maxilla for fabricating fixed prosthesis in biomechanical terms. This study investigated the effect of dental implant localizations in anterior maxilla on the strain values around implants using a three dimensional finite elements analysis method. Obtained strain values were compared to the data in Frost's mechanostat theory. The entire totally edentulous maxilla was modeled using computer tomography images and five models were prepared representing different implant localizations. The distribution of implants in the models was as follows: two canines in the first model, two canines and one central incisor in the second model, two canines and central incisor in the third model, two canines and one lateral incisor in the fourth model and two canines and two lateral incisors in the fifth model. Anatomic abutments with a gingival height of 2 mm and angle of 15° were used as the abutments to fabricate one piece cemented metal fused to porcelain restoration. A chewing strength of 100 N was applied to the cingulum of all crowns at a 45° angle. Maximum strain values in all models were measured in cortical bone in implant necks. The highest strain value was measured in the first model at the cortical bone area (3037 microstrain). Except the first model, all models showed micro strain values within 1000-3000 microstrain. The fifth model was the least risky method in biomechanical terms. The results of this study should be compared with different clinical scenarios (for example different implant designs and sizes). Due to the limitations of three-dimensional finite elements analysis studies, the findings of the study need to be supported by clinical studies.
Ng, Wuey Min
Purpose. This study investigates the association between focal nodular mass with low signal in Hoffa's fat pad adjacent to anterior femoral cartilage of the knee (FNMHF) and focal cartilage abnormality in this region. Method. The magnetic resonance fast imaging employing steady-state acquisition sequence (MR FIESTA) sagittal and axial images of the B1 and C1 region (described later) of 148 patients were independently evaluated by two reviewers and categorized into four categories: normal, FNMHF with underlying focal cartilage abnormality, FNMHF with normal cartilage, and cartilage abnormality with no FNMHF. Results. There was a significant association (p = 0.00) between FNMHF and immediate adjacent focal cartilage abnormality with high interobserver agreement. The absence of focal nodular lesions next to the anterior femoral cartilage has a very high negative predictive value for chondral injury (97.8%). Synovial biopsy of focal nodular lesion done during arthroscopy revealed some fibrocollagenous tissue and no inflammatory cells. Conclusion. We postulate that the FNMHF adjacent to the cartilage defects is a form of normal healing response to the cartilage damage. One patient with FHMHF and underlying cartilage abnormality was rescanned six months later. In this patient, the FNMHF disappeared and normal cartilage was observed in the adjacent region which may support this theory. PMID:27213085
Ferrario, V F; Sforza, C; Guazzi, M; Serrao, G
Craniofacial growth and development involve both size and shape variations. Shape variations can be assessed independently from size using mathematical methods such as the elliptic Fourier analysis, which allows a global evaluation of the shape of organs identified by their outlines independently from size, spatial orientation, and relation to reference planes. The mandibular outlines were digitized from the tracings of the Bolton standards (lateral view) from 1 to 18 years of age, and the age differences in shape independently from size were quantified using the elliptic Fourier series. A "morphologic distance" MD (i.e., a measurement of differences in shape) between each younger mandible and the oldest one was computed using the relevant Fourier coefficients like the cartesian coordinates in standard metric measurements. MD equals 0 when the profiles are identical. MD (Y) between the Bolton standard at 18 years of age and all the other Bolton tracings were significantly correlated (correlation coefficient r = 0.987, P < or = 0.001) with age (X) (semi-logarithmic interpolation Y = -3.87.log(e) X + 13.593). Differences between the size-independent shape of the Bolton standard at 18 years and the relevant plot at 1 year were located at the chin, gonion, coronoid process, anterior border of the ramus. Size differences were measured from the areas enclosed by the mandibular outlines. Mandibular area (Y) increased about 2.58 times from 1 to 18 years of age (X) (Y = -0.071.X2 + 4.917.X + 35.904, r = 0.997, P < or = 0.001). The shape effect was largely overwhelmed by the very evident size increments, and it could be measured only using the proper mathematical methods. The method developed could also be applied to the comparison between healthy and diseased individuals.
Franco, Alexandre A.; Cevidanes, Lucia Helena S.; Phillips, Ceib; Rossouw, Paul Emile; Turvey, Timothy A.; Carvalho, Felipe de Assis R.; de Paula, Leonardo K.; Quintão, Cátia Cardoso A.; Almeida, Marco Antonio O.
PURPOSE To evaluate the three-dimensional changes in the position of the condyles, rami, and chin from 1 to 3 years after mandibular advancement surgery. METHOD This prospective observational study used pre and postoperative CBCT scans of 27 subjects with skeletal Class II jaw relationship and normal or deep overbite. An automatic technique of cranial base superimposition was used to assess positional and/or bone remodeling changes that were visually displayed and quantified using 3D color maps. An analysis of covariance with presence of genioplasty, age at the time of surgery, and sex as explanatory variables was used to estimate and test the adjusted mean changes for each region of interest. RESULTS The chin rotated downward and backwards between the 1 and 3 years post-surgery. Changes ≥ 2mm were observed in 17% of the cases. The mandibular condyles presented displacements and/or bone remodeling ≥ 2mm on the anterior surface (21% of the cases on the left and 13% on the right side), superior surfaces (8% on both sides) and lateral poles (17% on the left and 4% on the right side). The posterior borders of the rami exhibited symmetric lateral or rotational displacements in 4% of the cases. CONCLUSION In the hierarchy of surgical stability, mandibular advancement surgery is considered one of the most stable surgical procedures However, between 1 and 3 years post-surgery approximately 20% of the patients had 2-4 mm changes in the horizontal and vertical chin position, and/or changes in condylar position and adaptive bone remodeling. PMID:23769460
Aims and objectives To measure the prevalence of anterior teeth trauma in 9- to 14-year-old schoolchildren and their association with predisposing factors, such as lip competence, molar relationship, overjet, and variables, such as age, gender, and cause of trauma. Materials and methods Epidemiological cross-sectional study was carried out among 3,012 schoolchildren aged 9 to 14 years in Navi Mumbai (Kharghar-Belapur region). The sample size was derived using the stratified random sampling method; we picked six schools from the region. These schools had 3,000 students in the acceptable age group of the study which constituted our final sample size. All children were examined for traumatic dental injuries, and the children with positive findings were further examined for lip competence, Angle’s molar relationship, and overjet. The results were statistically analyzed using cross-tabulation and Chi-square test. Results The prevalence of dental injuries was 7.3%, and the ratio of male to female children was found to be 1.6:1. The maximum number of traumatic dental injuries was found with class I molar relationship and overjet less than 3.5 mm in children with competent lips. Maximum number of injuries occurred in the age group of 13-14 years. The most predominant type of injury was the enamel fracture and the most common cause determined was due to fall. Conclusion The present study is a collection of data on traumatic injuries to anterior teeth, which is seen very commonly in day-to-day practice. The frequency and cause of traumatic injuries to anterior teeth is important for identification of risk groups, treatment needs, and cost involved in order for establishing effective preventive measures. How to cite this article Hegde R, Agrawal G. Prevalence of Traumatic Dental Injuries to the Permanent Anterior Teeth among 9- to 14-year-old Schoolchildren of Navi Mumbai (Kharghar-Belapur Region), India. Int J Clin Pediatr Dent 2017;10(2):177-182. PMID:28890619
Panampally, George-Kurian; Chen, Yong; Tian, Tian
Objectives: The purpose of the present study was to evaluate mandibular talon cusps distribution from the comprehensive literature search and proposal of new classification Material and Methods: The study was a review of articles published in the English language from January 1960 to December 2013. The PubMed/MEDLINE/Google Scholor databases were searched electronically using ‘talon cusp’, ‘dens evaginatus’, ‘anterior teeth’, mandible, ‘primary dentition’ and ‘ permanent dentition’ as search terms in various combinations. The citation lists from the included references were subsequently examined, and a hand search was also performed in an attempt to identify additional reports. The distribution, characteristics, common tooth type, associated dental anomaly and proposal of new classification have been included in final data analysis. Descriptive statistics were carried out using Chi square test (SPSS, version 17). Results: Overall 37 citations were retrieved from the literature where one was prevalence studies and rest were case reports among those two were duplication. Total 35 articles with 43 patients were reported on mandibular talon cusps. Males were predominantly affected than females (p<0.05). Eight cases (19%) were reported in archeological skulls 81% were clinical reports. Forty cases (93%) were reported in permanent dentition while 7% cases in primary dentition. Lingual mandibular talon are more common than facial type in permanent dentition facial talons (p<0.05). Seven cases (18%) were bilaterally involved. Double tooth (45%) was commonly associated with mandibular talons. Most of the cases reported from Asia and asia derived populations. Conclusions: Central incisor is the most common tooth type that effected by talon cusp in permanent dentition and lateral incisor is in primary dentition. Lingual talons are common in mandible. Double tooth common dental anomaly associated with mandibular talon cusp. Most of the case reported from
Mallineni, Sreekanth-Kumar; Panampally, George-Kurian; Chen, Yong; Tian, Tian
The purpose of the present study was to evaluate mandibular talon cusps distribution from the comprehensive literature search and proposal of new classification Material and Methods: The study was a review of articles published in the English language from January 1960 to December 2013. The PubMed/MEDLINE/Google Scholor databases were searched electronically using 'talon cusp', 'dens evaginatus', 'anterior teeth', mandible, 'primary dentition' and ' permanent dentition' as search terms in various combinations. The citation lists from the included references were subsequently examined, and a hand search was also performed in an attempt to identify additional reports. The distribution, characteristics, common tooth type, associated dental anomaly and proposal of new classification have been included in final data analysis. Descriptive statistics were carried out using Chi square test (SPSS, version 17). Overall 37 citations were retrieved from the literature where one was prevalence studies and rest were case reports among those two were duplication. Total 35 articles with 43 patients were reported on mandibular talon cusps. Males were predominantly affected than females (p<0.05). Eight cases (19%) were reported in archeological skulls 81% were clinical reports. Forty cases (93%) were reported in permanent dentition while 7% cases in primary dentition. Lingual mandibular talon are more common than facial type in permanent dentition facial talons (p<0.05). Seven cases (18%) were bilaterally involved. Double tooth (45%) was commonly associated with mandibular talons. Most of the cases reported from Asia and asia derived populations. Central incisor is the most common tooth type that effected by talon cusp in permanent dentition and lateral incisor is in primary dentition. Lingual talons are common in mandible. Double tooth common dental anomaly associated with mandibular talon cusp. Most of the case reported from Asia. Talon cusps should be classified as facial
Nogami, H; Hoshino, R; Ogasawara, K; Miyamoto, S; Hisano, S
Recent studies have revealed the occurrence of five first exon variants of the rat prolactin receptor mRNA, suggesting that multiple promoters direct prolactin receptor transcription in response to different regulatory factors. In the present study, regional expression of these first exon variants, as well as two prolactin receptor subtypes generated by alternative splicing, was examined in the brains and anterior pituitary glands of female rats. Expression of the long-form was detected in the choroid plexus, hypothalamus, hippocampus, cerebral cortex and anterior pituitary gland, whereas the short form was detected only in the choroid plexus. E1-3 mRNA, a first exon variant, was detected in the choroid plexus, hypothalamus, and anterior pituitary gland, whereas E1-4 was detected only in the choroid plexus. Other variants were not detectable by the polymerase chain reaction protocol employed in this study. Ovariectomy increased the short form in the choroid plexus and the E1-3 expression in the choroid plexus and pituitary gland, but changes in the long-form and E1-4 expression were minimal. Replacement of oestrogens and prolactin suggest that oestrogens down-regulate E1-3 expression in the choroid plexus and pituitary gland, and that the negative effect of oestrogen is mediated by prolactin in the pituitary gland. The present results revealed the region-specific promoter usage in prolactin receptor mRNA transcription, as well as the involvement of oestrogens in the regulation of E1-3 mRNA expression in the brain and pituitary gland.
Lops, Diego; Bressan, Eriberto; Parpaiola, Andrea; Sbricoli, Luca; Cecchinato, Denis; Romeo, Eugenio
Aim of this study was to verify if the type of implant abutment manufacturing, stock or cad-cam, could influence the maintenance of stable gingival margins around single restorations in anterior areas. After 16 weeks of healing, implants (Osseospeed, Astra Tech Dental Implant) were positioned. Depending on the different fixture inclination and the thickness of buccal peri-implant soft tissue, abutment selection resulted in four groups: Group 1 (patients with zirconia ZirDesign(®) stock abutments), Group 2 (titanium stock TiDesign(®) abutments), Group 3 (zirconia cad-cam abutments), and Group 4 (titanium cad-cam abutments). The following parameters were assessed: buccal gingival margin modification (BGM). The modification of the implant gingival margin was followed at 1 and 2 years of follow-up. A computerized analysis was performed for measurements. Differences between soft tissue margin at baseline and after 2 years measured the gingival margin recession. A general linear model was used to evaluate each group in relation to gingival recession after two years. Tukey's post hoc test was used to compare the mean REC indexes of each group of abutments. Seventy-two healthy patients (39 males and 33 females; mean age of 46 years) scheduled for single gap rehabilitation in anterior areas were enrolled. A 100% of implant survival rate was observed after 24 months of function. One failure occurred due to fracture of a Zirconia cad-cam abutment. Moreover, two abutment screw unscrewing were observed. Both for zirconia and titanium stock abutments (Group 1 and 2), the mean recession of implant buccal soft tissue was of 0.3 mm (SD of 0.3 and 0.4 mm, respectively). Soft tissue mean recession of zirconia and titanium cad-cam abutments (Group 3 and 4) was of 0.1 and -0.3 mm, respectively (SD of 0.3 and 0.4 mm, respectively). REC values of cad-cam titanium abutments (Group 4) were significantly lower than that of Group 1 (-0.57 mm), Group 2 (-0.61 mm), and Group 3 (-0.40 mm
Brown, D T; Gaudet, E L; Phillips, C
This study evaluates whether extended full-time wear of a partial coverage mandibular anterior repositioning splint (MORA) causes intrusion of posterior teeth and determines the effect on jaw position. Sixty-four patients from two private orthodontic practices were studied using cephalometric radiographs to measure vertical change in position of the anterior and posterior teeth and the mandible. The splint wear time ranged from a minimum of one half year to a maximum of 4.8 years, with a mean of 1.33 years. No significant change was recorded in the distance from the mandibular molar to the mandibular plane. On average, the maxillary incisor and maxillary molar extruded about 1 mm, while the mandibular molar was unchanged and the mandibular incisor intruded about 0.6 mm. Posterior face height increased an average of 1.6 mm, and anterior face height increased an average of 2.7 mms. In 20% of the patients, intrusion of the mandibular molars of 1 mm or more occurred. In 41%, extrusion of the maxillary incisors of 1 mm or more was noted. Intrusion of the upper molars or extrusion of the lower incisors occurred in only 5% of the patients. The data indicates that only a very small proportion of patients having long term splint therapy using the MORA have clinically significant molar intrusion. Change in mandibular position was expressed in a vertical increase in posterior and anterior face height. Only very small changes occurred in antero-posterior position.
Lops, Diego; Parpaiola, Andrea; Paniz, Gianluca; Sbricoli, Luca; Magaz, Vanessa Ruiz; Venezze, Alvise Cenzi; Bressan, Eriberto; Stellini, Edoardo
The aim of this study was to compare the interproximal papilla stability of restorations supported by computer-aided design/computer-assisted manufacture (CAD/CAM) abutments to those supported by prefabricated stock abutments in anterior areas over a 2-year follow-up. Abutments were selected depending on implant inclination and thickness of buccal peri-implant soft tissues from the following: zirconia stock, titanium stock, zirconia CAD/CAM and titanium CAD/CAM. Differences between the height of the papilla tip were measured (REC). REC values of titanium and zirconia CAD/CAM abutments were significantly lower than those of titanium and zirconia stock. The use of titanium and zirconia CAD/CAM abutments is related to better interproximal papillae stability.
To examine morphological interrelationships between canine size and mandibular corpus shape, inter-sex comparisons were made in the hamadryas baboon and the Japanese monkey, known to display extreme and moderate canine dimorphism, respectively. Results of adult comparisons showed that all mandibular dimensions were significantly larger in the males than in the females in both species. In the hamadryas baboon, the males also exhibited a higher ratio of anterior to posterior corpus height than the females. This sex difference in corpus shape was not significant in the Japanese monkey, indicating lack of involvement of canine dimorphism. Analysis of mandibular growth patterns in the hamadryas baboon demonstrated that significant sexual size difference did not occur before incisor eruption, and that the anteriorly high corpus of the adult male mandible was associated with a rapidly increasing symphyseal height after incisor eruption. It was also shown that the female canine started to erupt shortly after incisor eruption, while the forming male canine continued to stay near the mandibular base and developed further in size until eruption. The relative positions of the incisors kept shifting upwards even after eruption in the males, while they hardly changed in the females. It is therefore suggested that the prolonged development and size increase of the male canine is accompanied by further enlargement of the symphysis, resulting in the higher anterior corpus of the adult males compared to the adult females. The results thus indicate the importance of understanding the spatial relationships of the developing teeth in interpreting mandibular morphology.
Kitadate, Yu; Shigenobu, Shuji; Arita, Kayo; Kobayashi, Satoru
Drosophila germline stem cells are regulated by the somatic microenvironment, or "niche," which ensures that the stem cells can both self-renew and produce functional gametes throughout adult life. However, despite its prime importance, little is known about how niche formation is regulated during gonadal development. Here, we demonstrate that a receptor tyrosine kinase, Sevenless (Sev), is required to ensure that the niche develops in the anterior region of the male embryonic gonads. Sev is expressed in somatic cells within the posterior region of the gonads. Sev is activated by a ligand, Bride of sevenless (Boss), which is expressed by the germline, to prevent ectopic niche differentiation in the posterior gonadal somatic cells. Thus, we propose that signal transduction from germline to soma restricts expansion of the germline-stem-cell niche in the gonads.
Singh Khinda, Vineet Inder; Kallar, Shiminder; Singh Brar, Gurlal
ABSTRACT Macrodontia (megadontia, megalodontia, mac rodontism) is a rare shape anomaly that has been used to describe dental gigantism. Mandibular second premolars show an elevated variability of crown morphology, as are its eruptive potential and final position in the dental arch. To date, only eight cases of isolated macrodontia of second premolars have been reported in the literature. This case report presents clinical and radiographic findings of unusual and rare case of isolated unilateral molarization of left mandibular second premolar. How to cite this article: Mangla N, Khinda VIS, Kallar S, Brar GS. Molarization of Mandibular Second Premolar. Int J Clin Pediatr Dent 2014;7(2):137-139. PMID:25356014
Parthasarathy, S.; Sripriya, R.
Mandibulo facial injuries present special problems to the anesthesiologist in terms of the difficult airway. Hence, if regional anesthesia could be possible, it necessarily removes the major concern with airway access. We present a case of bilateral mandibular condylar fracture dislocation with the maxillary and mandibular nerve blocks on both sides. The surgery went on smoothly without any perioperative problems. PMID:26417146
Dillon, Jasjit K; Christensen, Brian; McDonald, Tyler; Huang, Steve; Gauger, Peter; Gomez, Preston
Patients with mandibular trauma in the greater Seattle region are frequently transferred to Harborview Medical Center (HMC) despite trained providers in the surrounding communities. HMC receives poor reimbursement for these services, creating a disproportionate financial burden on the hospital. In this study we aim to identify the variables associated with increased cost of care, measure the relative financial impact of these variables, and quantify the revenue loss incurred from the treatment of isolated mandibular fractures. A retrospective chart review was conducted of patients treated at HMC for isolated mandibular fractures from July 1999 through June 2010, using International Classification of Diseases, Ninth Revision and Current Procedural Terminology coding. Data collected included demographics, injury, hospital course, treatment, outcomes, and billing. The study included 1,554 patients. Total billing was $22.1 million. Of this, $6.9 million was recovered. We found that there are multiple variables associated with the increased cost of treating mandibular fractures; 4 variables--length of hospital stay, treatment modality, service providing treatment, and method of arrival--accounted for 49.1% of the total variance in the amount billed. In addition, we found that the unsponsored portion of our patient population grew from 6.7% to 51.4% during the study period. Our results led to specific cost-efficiency recommendations: 1) perform closed reduction whenever possible; 2) encourage performing procedures with patients under local anesthesia (closed reductions and arch bar removals); 3) provide improved and shared training among the services treating craniofacial trauma; 4) encourage arrival by privately owned vehicle; 5) provide outpatient treatment, when applicable; 6) offer provider incentives to take trauma call; and 7) offer hospital incentives to treat patients and not transfer them. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons
Camino, Rubens; Manzi, Marcello Roberto; de Carvalho, Matheus Furtado; Luz, João Gualberto de Cerqueira; Pimentel, Angélica Castro; Deboni, Maria Cristina Zindel
Introduction: Disc displacement without reduction with limited opening is an intracapsular biomechanical disorder involving the condyle-disc complex. With the mouth closed, the disc is in an anterior position in relation to the condylar head and does not reduce with mouth opening. This disorder is associated with persistent limited mandibular opening. Case report: The patient presented severe limitation to fully open the mouth, interfering in her ability to eat. Clinical examination also revealed maximum assisted jaw opening (passive stretch) with less than 40 mm of maximum interincisal opening. Magnetic resonance imaging was the method of choice to identify the temporomandibular disorders. Conclusion: By means of reporting this rare case of anterior disc displacement without reduction with limited opening, after traumatic extraction of a mandibular third molar, in which manual reduction of temporomandibular joint articular disc was performed, it was possible to prove that this technique is effective in the prompt restoration of mandibular movements. PMID:26560828
Waggoner, William F
A variety of esthetic restorative materials are available for restoring primary incisors. Knowledge of the specific strengths, weakness, and properties of each material will enhance the clinician's ability to make the best choice of selection for each individual situation. Intracoronal restorations of primary teeth may utilize resin composites, glass ionomer cements, resin-modified ionomers, or polyacid-modified resins. Each has distinct advantages and disadvantages and the clinical conditions of placement may be a strong determining factor as to which material is utilized. Full coronal restoration of primary incisors may be indicated for a number of reasons. Crowns available for restoration of primary incisors include those that are directly bonded onto the tooth, which generally are a resin material, and those crowns that are luted onto the tooth and are some type of stainless steel crown. However, due to lack of supporting clinical data, none of the crowns can be said to be superior to the others under all circumstances. Though caries in the mandibular region is rare, restorative solutions for mandibular incisors are needed. Neither stainless steel crowns nor celluloid crown forms are made specifically for mandibular incisors. Many options exist to repair carious primary incisors, but there is insufficient controlled, clinical data to suggest that one type of restoration is superior to another. This does not discount the fact that dentists have been using many of these crowns for years with much success. Operator preferences, esthetic demands by parents, the child's behavior, and moisture and hemorrhage control are all variables which affect the decision and ultimate outcome of whatever restorative treatment is chosen.
De Feyter, Henk M M L; Schaart, Gert; Hesselink, Matthijs K; Schrauwen, Patrick; Nicolay, Klaas; Prompers, Jeanine J
1H MR spectroscopy (MRS) has proved to be a valuable noninvasive tool to measure intramyocellular lipids (IMCL) in research focused on insulin resistance and type II diabetes in both humans and rodents. An important determinant of IMCL is the muscle fiber type, since oxidative type I fibers can contain up to three times more IMCL than glycolytic type II muscle fibers. Because these different muscle fiber types are inhomogeneously distributed in rodent muscle, in the present study we investigated the distribution of IMCL within the rat tibialis anterior muscle (TA) in vivo using single-voxel 1H MRS along with the muscle fiber distribution in the TA ex vivo determined from immunohistological assays. IMCL levels in the TA differed by up to a factor of 3 depending on the position of the voxel. The distribution of IMCL over the TA cross section was not random, but emerged in a pattern similar to the distribution of the predominantly oxidative muscle fiber types. Dietary interventions, such as high-fat feeding and 15 hr of fasting, did not significantly change this typical fiber type-dependent pattern of IMCL content. These results stress the importance of voxel positioning when single-voxel 1H MRS is used to study IMCL in rodent muscle. Copyright (c) 2006 Wiley-Liss, Inc.
Ihlow, Dankmar; Kubein-Meesenburg, Dietmar; Hunze, Justus; Dathe, Henning; Planert, Jens; Schwestka-Polly, Rainer; Nägerl, Hans
Radii for concave-convex vertical stripping instruments can be derived from measurements of the natural curvature morphology in the horizontal contact area of the mandibular dentition. The concave-convex adjustment of contacts in the anterior dental arch with a newly developed set of concave-convex stripping instruments should enable orthodontic crowding problems to be alleviated biomechanically.
mandible upon closure for approximately 2 to 4 weeks. Cephalometrlc Analysis * . Each patient had standardized lateral cephalometric radiographs taken (Quint...thickness on changes in vertical dimension as it affected the total anterior facial height at B point. The vertical closure from splint removal ranged...conjunction with increases in vertical dimension . Rigid stabilization with good bony apposition of the mandibular segments during fixation
Haas, Daniel A
and Overview. The limited success rate of the standard inferior alveolar nerve block (IANB) has led to the development of alternative approaches for providing mandibular anesthesia. Two techniques, the Gow-Gates mandibular nerve block and the Akinosi-Vazirani closed-mouth mandibular nerve block, are reliable alternatives to the traditional IANB. The Gow-Gates technique requires the patient's mouth to be open wide, and the dentist aims to administer local anesthetic just anterior to the neck of the condyle in proximity to the mandibular branch of the trigeminal nerve after its exit from the foramen ovale. The Akinosi-Vazirani technique requires the patient's mouth to be closed, and the dentist aims to fill the pterygomandibular space with local anesthetic. Both techniques are indicated for any type of dentistry performed in the mandibular arch, but they are particularly advantageous when the patient has a history of standard IANB failure owing to anatomical variability or accessory innervation. Having the skill to perform these alternative anesthetic techniques increases dentists' ability to provide successful local anesthesia consistently for all procedures in mandibular teeth.
Kim, Yeon-Ho; Won, Yu-Jin; Kim, Moon-Key
Purpose To analyze the relative position of the mandibular foramina (MnFs) in patients diagnosed with skeletal class III malocclusion. Materials and Methods Computed tomography (CT) images were collected from 85 patients. The vertical lengths of each anatomic point from the five horizontal planes passing through the MnF were measured at the coronoid process, sigmoid notch, condyle, and the gonion. The distance from the anterior ramus point to the posterior ramus point on the five horizontal planes was designated the anteroposterior horizontal distance of the ramus for each plane. The perpendicular distance from each anterior ramus point to each vertical plane through the MnF was designated the horizontal distance from the anterior ramus to the MnF. The horizontal and vertical positions were examined by regression analysis. Results Regression analysis showed the heights of the coronoid process, sigmoid notch, and condyle for the five horizontal planes were significantly related to the height of the MnF, with the highest significance associated with the MnF-mandibular plane (coefficients of determination (R2): 0.424, 0.597, and 0.604, respectively). The horizontal anteroposterior length of the ramus and the distance from the anterior ramus point to the MnF were significant by regression analysis. Conclusion The relative position of the MnF was significantly related to the vertical heights of the sigmoid notch, coronoid process, and condyle as well as to the horizontal anteroposterior length of the ascending ramus. These findings should be clinically useful for patients with skeletal class III mandibular prognathism. PMID:27358814
Coquerelle, Michael; Bookstein, Fred L; Braga, José; Halazonetis, Demetrios J; Weber, Gerhard W
Comparison of the early development of the mandibular symphysis between primates and modern humans is of particular interest in human palaeontology. Using geometric morphometric methods, we explored and compared the ontogenetic shape changes of 14 chimpanzee mandibles (Pan troglodytes) against 66 human CT-scanned mandibles over the age range from fetal life to the complete emergence of the deciduous dentition in a visualization incorporating the deciduous tooth arrangement. The results reveal that the symphysis is anteriorly inclined in the youngest chimpanzee fetuses but develops an increasingly vertical orientation up until birth. At the same time, the anterior teeth reorient before a vertical emergence, and a symphyseal tuber appears on the labial side. When the deciduous canine emerges, the symphysis inclines anteriorly again, exhibiting the adult characteristic slope. These two phases are characterized by a repositioning of the simian shelf. Unlike chimpanzees, the human symphysis remains vertical throughout fetal development. However, the combination of morphological changes observed in chimpanzee fetuses is similar to that of modern humans after birth, as the mental region projects forward. By elongating the alveolar process, the inclination of the chimpanzee symphysis could be a key event for emergence of the deciduous canine, as space is lacking at the alveolar ridge in a vertical symphysis once the deciduous incisors and molars have emerged. The repositioning of the simian shelf suggests that the suprahyoid muscles have a significant influence on the anterior growth of the symphysis. The anteroposterior positioning of the basal symphysis in both species may be related to hyoid bone position during ontogeny. PMID:20807267
Cillo, Joseph E; Finn, Richard
To evaluate the long-term outcome of simultaneous split thickness skin graft (STSG) vestibuloplasty and endosseous implant placement for implant-supported overdentures in patients with shallow mandibular vestibules. This was a retrospective evaluation of 13 consecutive white male patients who underwent simultaneous mandibular vestibuloplasty with STSG combined with placement of 2 to 4 mandibular endosseous implants for construction of an implant-supported mandibular overdenture with a minimum of 2-year follow-up. Patients' charts were evaluated for implant survival and prosthetic success. Thirteen male patients at an average age of 60.4 years who had undergone simultaneous STSG mandibular vestibuloplasty and endosseous implant placement in the anterior mandible, were followed for an average of 43 months and were retrospectively evaluated. A total of 40 implants (average of 3 implants per patient) were placed in the anterior mandible in preparation for an implant-supported overdenture placement. There were no complications in graft or recipient sites, implant placement, or overdenture construction. The endosseous dental implant integration rate was 97.5% and the prosthetic success rate was 100%. Simultaneous STSG mandibular vestibuloplasty for vestibular lengthening and placement of mandibular endosseous implants in preparation for mandibular implant-supported overdentures is a reliable method in patients with shallow mandibular vestibules.
Tanaka, Eiji; Iwabe, Tatsunori; Kawai, Nobuhiko; Nishi, Mika; Dalla-Bona, Diego; Hasegawa, Takuro; Tanne, Kazuo
Control of the height of posterior dentoalveolar regions is of great importance for the correction of skeletal open bite. Traditionally, second premolar extraction facilitates the closure of open bite by inducing a counterclockwise mandibular rotation without molar intrusion. This article reports treatment for a 24-year six-month-old female patient with an open bite and large anterior facial height. She complained of occlusal disturbances and difficulty of lip closure because of the open bite. Overjet and overbite were +3.0 mm and -3.0 mm, respectively. To correct open bite and crowding, the bilateral extraction of the maxillary and mandibular second premolars plus multibracket appliances for mesial movement of the molars was selected as the treatment plan. After a two-year treatment, an acceptable occlusion was achieved, the lower anterior facial height was decreased, and the lips showed less tension in a lip closure. An acceptable occlusion was maintained without recurrence of the open bite during a three-year retention period, indicating a long-term stability of the occlusion. The results of this treatment indicated that the correction of open bite with no or less molar intrusion or incisor extrusion is of great importance for achieving stable occlusion and avoiding the relapse of open bite.
Ferrario, V F; Sforza, C; De Franco, D J
Pre-treatment lateral cephalograms of 41 skeletal Class I girls aged 11 to 15 were divided according to MP-SN angle: lower than 28 degrees (hypodivergent, 10 girls), between 31 and 34 degrees (normodivergent, 18 girls), or larger than 37 degrees (hyperdivergent, 13 girls). The mandibular outlines were traced and digitized, and differences in shape were quantified using the elliptic Fourier series. Size differences were measured from the areas enclosed by the mandibular outlines. Shape differences were assessed by calculating a morphological distance (MD) between the size-independent mean mathematical reconstructions of the mandibular outlines of the three divergency classes. Mandibular shape was different in the three classes: large variations were found in hyperdivergent girls versus normodivergent girls (MD = 4.61), while smaller differences were observed in hypodivergent girls (MD versus normodivergent 2.91). Mean size-independent mandibular shapes were superimposed on an axis passing through the centres of gravity of the condyle and of the chin. Normodivergent and hyperdivergent mandibles differed mostly at gonion, the coronoid process, sigmoid notch, alveolar process, posterior border of the ramus, and along the mandibular plane. A significant size effect was also found, with smaller mandibles in the hyperdivergent girls.
Bourlet, Jerôme; Château, Joseph; Jacquemart, Mathieu; Dufour, Clémence; Mojallal, Ali; Gleizal, Arnaud
Background: Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery, and free fibular flap is the gold standard for this indication. However, there are alternatives; nonvascular bone grafting is one of them, and we present the costal grafting for mandibular reconstruction, a classic technique that is reliable, efficient, and produced less morbidity than the technique of using composite free flaps. Method: A 9-year retrospective review of 54 patients treated surgically for mandibular reconstruction was performed. The criterion mainly analyzed was graft survival. The surgical technique was described in detail. Results: A total of 54 patients with mandibular bone defect were identified. Five symphysis, 46 corpus, and 20 ramus defects were considered. These patients underwent reconstruction by costal grafting, and the engrafting was successful in 92.6% of cases. Dental rehabilitation with dental implants was realized in 70% of cases. Conclusions: The approach described in this article allowed the authors to obtain good results with costal grafting for mandibular reconstruction and dental rehabilitation. Costal grafting is a good alternative for fibula free flap in specific indications. Reconstruction of mandibular bone defect is a common indication in craniomaxillofacial surgery. Since the 1980s, the gold standard for these defects is the use of free fibular flap.1 In some cases, this technique is contradicted; the surgeon then has several possibilities for the use of free osteomyocutaneous flaps (iliac crest, scapula, and serrato-costal flaps).2–8 PMID:26893990
Rao, Prasanna Kumar; Mascarenhas, Rohan; Shetty, Shishir Ram
Talon cusp, also known as an eagle's talon, is a dental anomaly that occurs on the lingual aspect of teeth commonly, but occurrence on the facial aspect has rarely been reported. It is an extra cusp on an anterior tooth, which arises as a result of evagination on the surface of a crown before calcification has occurred. The incidence of talon cusp on lingual side is less than 6% and is even lesser on the facial aspect. Commonly involved teeth are maxillary incisors, usually unilateral but in some instances bilateral. The classical radiographical feature of talon cusp is double teeth appearance. The anomaly has been reported to be unusual in the mandibular dentition and extremely rare on the facial aspect. We report one such extremely rare case of facial talon cusp in mandibular central incisor. PMID:22135696
Burnett, C A
The purpose of this study was to describe the mandibular incisor positions for the 24 consonant sounds of the English language. Further aims were to determine if the incisor format for each sound is affected by its position in a word, or by combination with an open or closed vowel. A total of 30 young adult subjects had their incisal positions determined using an electrognathographic technique during performance of a number of speech tests. The mean values of the 24 consonants, in the vertical direction, showed a range from the intercuspal position of 2.5 mm for a sibilant sound to 11.7 mm for the /H/ sound, and an anteroposterior range of 1.4 mm anterior for a sibilant sound to 1.8 mm posterior for the /M/ sound. The range in the mean lateral dimension was always less than 1 mm on either side of the midline. The placement of a sound in the initial or final position in a word had no effect on the incisal position. The degree of vertical opening was significantly greater for 8 of the consonant sounds when in combination with an open vowel sound. The anteroposterior and lateral positions were unaffected by vowel association. The incisor position for consonant sounds is unaffected by initial or final word placement. Some consonant sound positions are affected by combination with an open or closed vowel sound. Sibilant sounds produced a clinically acceptable measure of the most superior and anterior speaking positions in all subjects.
Stéphan-Dubois, F; Bautz, A
On amputating either at the root of the pharynx or between the mouth and the genital pore, the posterior parts which are thereby isolated do not regenerate. However they are capable of surviving for ever a year, without feeding. The wounded region is occupied by neoblasts which degenerate within a few days after an initial secretory activity. Their degeneration is of autophagic type. The abortive blastems disappear only slowly, because the degeneration of their neoblasts is partly compensated by the continual immigration of new regeneration cells which come from the posterior region. Several months after amputation, under the effect of prolonged starvation, neoblasts and fixed parenchymal cells begin to degenerate.
Sugito, H; Shibukawa, Y; Kinumatsu, T; Yasuda, T; Nagayama, M; Yamada, S; Minugh-Purvis, N; Pacifici, M; Koyama, E
Symphyseal secondary cartilage is important for mandibular development, but the molecular mechanisms underlying its formation remain largely unknown. Here we asked whether Indian hedgehog (Ihh) regulates symphyseal cartilage development and growth. By embryonic days 16.5 to 18.5, Sox9-expressing chondrocytes formed within condensed Tgfβ-1/Runx2-expressing mesenchymal cells at the prospective symphyseal joint site, and established a growth-plate-like structure with distinct Ihh, collagen X, and osteopontin expression patterns. In post-natal life, mesenchymal cells expressing the Ihh receptor Patched1 were present anterior to the Ihh-expressing secondary cartilage, proliferated, differentiated into chondrocytes, and contributed to anterior growth of alveolar bone. In Ihh-null mice, however, symphyseal development was defective, mainly because of enhanced chondrocyte maturation and reduced proliferation of chondroprogenitor cells. Proliferation was partially restored in dual Ihh;Gli3 mutants, suggesting that Gli3 is normally a negative regulator of symphyseal development. Thus, Ihh signaling is essential for symphyseal cartilage development and anterior mandibular growth.
Chang, Hong-Po; Tseng, Yu-Chuan; Chang, Hsin-Fu
Mandibular prognathism (MP) or skeletal Class III malocclusion with a prognathic mandible is one of the most severe maxillofacial deformities. Facial growth modification can be an effective method of resolving skeletal Class III jaw discrepancies in growing children with dentofacial orthopedic appliances including the chincup, face mask, maxillary protraction combined with chincup traction and the Fränkel functional regulator III appliance. Orthognathic surgery in conjunction with orthodontic treatment is required for the correction of adult MP. The two most commonly applied surgical procedures to correct MP are sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy. Both procedures are suitable for patients in whom a desirable occlusal relationship can be obtained with a setback of the mandible, and each has its own advantages and disadvantages. In bilateral SSRO, the intentional ostectomy of the posterior part of the distal segment can offer long-term positioned stability. This may be attributable to reduction of tension in the pterygomasseteric sling that applies force in the posterior mandible. While various environmental factors have been found to contribute to the development of MP, heredity plays a substantial role. The relative contributions of genetic and environmental components in the etiology of MP are unclear. The recent identification of the genetic susceptibilities to MP constitutes the first step toward understanding the molecular pathogenesis of MP. Further studies in molecular biology are needed to identify the gene-environment interactions associated with the phenotypic diversity of MP and the heterogenic developmental mechanisms thought to be responsible for them.
Bertl, Michael H; Bertl, Kristina; Wagner, Manuel; Gahleitner, André; Stavropoulos, Andreas; Ulm, Christian; Mitteroecker, Philipp
The aim of this study was to compare mandibular form (i.e., size and shape) between patients with agenesis of the lower second premolar (P2) and a control group with no agenesis. Three hypotheses were tested: (H1) agenesis causes a change in mandibular morphology because of inadequate alveolar ridge development in the area of the missing tooth (mandibular plasticity); (H2) agenesis is caused by spatial limitations within the mandible (dental plasticity); and (H3) common genetic/epigenetic factors cause agenesis and affect mandibular form (pleiotropy). A geometric morphometric analysis was applied to cross-sectional images of computed tomography (CT) scans of three matched groups (n=50 each): (1) regularly erupted P2; (2) agenesis of P2 and the primary second molar in situ; and (3) agenesis of P2 and the primary second molar missing for >3 months. Cross-sections of the three areas of interest (first premolar, P2, first molar) were digitized with 23 landmarks and superimposed by a generalized Procrustes analysis. On average, the mandibular cross-sections were narrower and shorter in patients with P2 agenesis compared with that in the control group. Both agenesis groups featured a pronounced submandibular fossa. These differences extended at least one tooth beyond the agenesis-affected region. Taken together with the large interindividual variation that resulted in massively overlapping group distributions, these findings support genetic and/or epigenetic pleiotropy (H3) as the most likely origin of the observed covariation between mandibular form and odontogenesis. Clinically, reduced dimensions and greater variability of mandibular form, as well as a pronounced submandibular fossa, should be expected during the treatment planning of patients with P2 agenesis. PMID:27857074
Bertl, Michael H; Bertl, Kristina; Wagner, Manuel; Gahleitner, André; Stavropoulos, Andreas; Ulm, Christian; Mitteroecker, Philipp
The aim of this study was to compare mandibular form (i.e., size and shape) between patients with agenesis of the lower second premolar (P2) and a control group with no agenesis. Three hypotheses were tested: (H1) agenesis causes a change in mandibular morphology because of inadequate alveolar ridge development in the area of the missing tooth (mandibular plasticity); (H2) agenesis is caused by spatial limitations within the mandible (dental plasticity); and (H3) common genetic/epigenetic factors cause agenesis and affect mandibular form (pleiotropy). A geometric morphometric analysis was applied to cross-sectional images of computed tomography (CT) scans of three matched groups (n=50 each): (1) regularly erupted P2; (2) agenesis of P2 and the primary second molar in situ; and (3) agenesis of P2 and the primary second molar missing for >3 months. Cross-sections of the three areas of interest (first premolar, P2, first molar) were digitized with 23 landmarks and superimposed by a generalized Procrustes analysis. On average, the mandibular cross-sections were narrower and shorter in patients with P2 agenesis compared with that in the control group. Both agenesis groups featured a pronounced submandibular fossa. These differences extended at least one tooth beyond the agenesis-affected region. Taken together with the large interindividual variation that resulted in massively overlapping group distributions, these findings support genetic and/or epigenetic pleiotropy (H3) as the most likely origin of the observed covariation between mandibular form and odontogenesis. Clinically, reduced dimensions and greater variability of mandibular form, as well as a pronounced submandibular fossa, should be expected during the treatment planning of patients with P2 agenesis.
During oral rehabilitation of an edentulous patient with an implant-supported prosthesis, mandibular flexure must be considered an important biomechanical factor when planning the metal framework design, especially if implants are installed posterior to the interforaminal region. When an edentulous mandible is restored with a fixed implant-supported prosthesis connected by a fixed full-arch framework, mandibular flexure may cause needless stress in the overall restorative system and lead to screw loosening, poor fit of prosthesis, loss of the posterior implant, and patient's discomfort due to deformation properties of the mandible during functional movements. The use of a split-framework could decrease the stress with a precise and passive fit on the implants and restore a more natural functional condition of the mandible, helping in the longevity of the prosthesis. Therefore, the present clinical report describes the oral rehabilitation of an edentulous patient by a mandibular fixed implant-supported prosthesis with a split-framework to compensate for mandibular flexure. Clinical Significance. The present clinical report shows that the use of a split-framework reduced the risk of loss of the posterior implants or screws loosening with acceptable patient comfort over the period of a year. The split-framework might have compensated for the mandibular flexure during functional activities. PMID:26770841
Kamble, Vijaya; Kulkarni, Ameya; Pajnigara, Nilufer; Dhok, Avinash
Osteochondroma (OC) is a common slow growing tumour of bone. This lesion is frequently seen in the axial skeleton and is relatively uncommon in oral and maxillofacial region. In facial bones, it usually affects the mandibular condyle followed by coronoid process. Very few cases of condylar osteocondroma have been reported in the literature. The aim of this article was to present an atypical case of osteochondroma of bilateral mandibular condyle in an asymptomatic patient and facilitate making an exact diagnosis of it. To the best of our knowledge this is the 2nd case of this type reported in literature. PMID:27656529
Sheikhi, Mahnaz; Ghazizadeh, Maryam; Salehi, Mohammad Mahdi
One of the most common sites of injury of the facial skeleton is mandibular condyle. However, it is the least diagnosed site of trauma in the head and neck regions. A trauma to the mandible and specifically condylar zone during childhood, may lead to asymmetry or mandibular bilateral distortion, which is usually manifested in the second decade of life when the etiology is unknown to most people. This report is about an adult male complaining about facial asymmetry with an unknown source. Obvious clicking at the right side and shorter right ramus and condyle's head deviation directed us to a childhood trauma and fracture.
Kursoglu, Pinar; Capa, Nuray
There are multiple factors in cases of mandibular hypomobility. One of these factors is elongated coronoid process. Two cases are presented to illustrate elongated coronoid process leading to mandibular hypomobility to help prevent misdiagnosis by clinicians. Coronoid process elongation is a rare condition. Both cases reported here had pulpitis on the teeth, however endodontic treatment could not be performed due to the restricted mouth opening in both cases. There were clinical findings of restricted range of motion, especially during protrusive movements. The restrictive movements did not cause pain for either patient, and the patients were not aware of their restricted mouth opening. Panoromic radiographs were taken and evaluated. The radiographs showed elongated coronoid process bilaterally. Three-dimensional computerized tomography was taken in one case only, due to the patient's financial restrictions. In cases of restricted mandibular opening, elongated coronoid process must be considered when diagnosing the cause.
Zellner, Elizabeth G; Mhlaba, Julie M; Reid, Russell R; Steinbacher, Derek M
groups. Longer lengths of distraction correlated with narrower anterior mandibular angle and longer mandibular body length. Substantial airway enlargement occurs after mandibular distraction. Final airway volumes were similar between groups regardless of vector, which was confirmed by multivariate ANCOVA regression. The 2 methods achieved airway stabilization, with clinical outcomes similar between the 2 groups. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Kumar, Vaikunth Vijay; Rangarajan, Vedantham
PURPOSE This study evaluated the existence of golden proportion between the widths of the maxillary and mandibular anterior teeth in Indian population. MATERIALS AND METHODS The clinical tooth width measurements were recorded with the digital vernier calipers on 576 patients of both sexes in the age group of 21 - 30 years. Flexible ruler was used to determine the width of maxillary and mandibular anterior teeth on the patients by the same operator. The data obtained was statistically analyzed using paired student t-test (α=.05). RESULTS The golden proportion was not found between the width of the right central and lateral incisors in 53% of women and 47% of men. The results revealed the golden percentage was rather inconstant in terms of relative tooth width. CONCLUSION The golden proportion is an inappropriate method to relate the successive widths of the maxillary anterior teeth in Indian population. PMID:22737310
Garcia, Lily T; Bohnenkamp, David M
The lack of display of anterior metal clasps is a primary advantage of the A-P rotational-path mandibular RPD design. A disadvantage of this design is that it relies on rigidmetal guiding plates for anterior retention and stability. Loss of retention may require procedures much more involved than the simple adjustment of conventional RPD clasps. Proper adherence to design, survey, fabrication, and adjustment procedures described by the authors should result in an esthetically pleasing and well-retained tooth-supported removable prosthesis. This article recommends the A-P rotational-path mandibular RPD as a treatment the clinician can use to restore multiple missing anterior teeth and satisfy a patient's financial, esthetic, and functional requirements.
Bilginaylar, Kani; Orhan, Kaan; Uyanik, Lokman Onur
The aim of the present paper is to emphasize the importance of the mandibular interforaminal neurovascular bundle with a case and make a warning to dentists and surgeons during oral and maxillofacial surgeries, such as implant replacement, bone harvesting, genioplasty, open reduction of a mandibular fracture, and cyst enucleations at this region. In this paper, we present a 58-year-old male who referred with pain and a tingling sensation on the left lower lip. After radiographical, extraoral and intraoral examinations, findings indicated the lesion to be a cyst which was related with a periapical lesion of the canine tooth and extracted socket of first premolar tooth. After removal of a cyst, the mandibular incisive nerve was documented which was in relation to cyst cavity. PMID:27041907
Ahn, Hyo-Won; Chung, Kyu-Rhim; Kang, Suk-Man; Lin, Lu; Nelson, Gerald
In the correction of dental Class III molar relationship in skeletal Class II patients, uprighting of the mandibular posterior segments without opening the mandible is an important treatment objective. In the case reported herein, a C-tube miniplate fixed to the lower labial symphysis and connected with a nickel-titanium reverse-curved archwire provided effective uprighting of the lower molars, without the need of orthodontic appliances on the mandibular anteriors. Using this approach, an appropriate magnitude of force is exerted on the molars while avoiding any negative effect on the mandibular anteriors. PMID:23173121
Leeters, Irene P M; Davis, Ashlee; Zusterzeel, Robbert; Atwater, Brett; Risum, Niels; Søgaard, Peter; Klem, Igor; Nijveldt, Robin; Wagner, Galen S; Gorgels, Anton P M; Kisslo, Joseph
In contrast to LBBB patients less is known about patients with RBBB+LAFB regarding LV contractile abnormalities and the potential role of CRT. This study investigated whether patients with RBBB+LAFB morphology have echocardiographic mechanical strain abnormalities between the inferior and anterior LV walls, similar to abnormalities between septal and lateral walls in LBBB. Ten healthy volunteers with no-BBB, 28 LBBB and 28 RBBB+LAFB heart failure patients were included in this retrospective study. Two-dimensional regional-strains were obtained by speckle-tracking. Scar was assessed by CMR. Response on echo was defined as normal, classical, borderline or other pattern. The number of classical patterns in LBBB was significantly higher than in RBBB+LAFB and no-BBB groups (p<0.001 for both). Contrary, the RBBB+LAFB group showed a significantly higher number of borderline patterns compared to other groups (LBBB: p=0.042, no-block: p=0.012). In addition, RBBB+LAFB patients had more scar than LBBB patients (9.9% vs 3.4%, p=0.041), and the average amount of scar in each wall was also higher in RBBB+LAFB (<5% in LBBB and <16% in RBBB+LAFB). Patients with RBBB+LAFB on ECG and clinical HF demonstrate echocardiographic wall motion abnormalities between inferior and anterior LV walls, similar to abnormalities found between septal and lateral LV walls in patients with LBBB and HF. Fewer patients with RBBB+LAFB showed a classical pattern of opposing wall motion compared to LBBB. Factors that might alter strain patterns in RBBB+LAFB, including the detailed presence or absence of LV scar and coexisting block of the central fascicle, should be assessed in future studies. Copyright © 2016 Elsevier Inc. All rights reserved.
We report about 11 patients with periorbital fracture. Blow-out fracture and patients with fracture of the anterior wall of the frontal sinus. Treatment was operative osteosynthesis. We used for that the Mandibular Mesh System of 3M Company, Germany. We usually observed the patients for one year and got a firm unification of the fragments, as well a good cosmetic success from the beginning. We had not seen any complications caused by the osteosynthesis material. The author consider the most important advantages of this system to be the considerably smaller measurements, the possibility to form the osteosynthetical sheets out of a lattice, the higher solidity of Titanium and the good formability.
Maras, P M; Petrulis, A
In many rodent species, such as Syrian hamsters, reproductive behavior requires neural integration of chemosensory information and steroid hormone cues. The medial amygdala (MA) processes both of these signals through anatomically distinct sub-regions; the anterior region (MeA) receives substantial chemosensory input, but contains few steroid receptor-labeled neurons, whereas the posterodorsal region (MePD) receives less chemosensory input, but contains a dense population of steroid receptors. Importantly, these sub-regions have considerable reciprocal connections, and the goal of this experiment was therefore to determine whether interactions between MeA and MePD are required for male hamsters' preference to investigate female over male odors. To functionally disconnect MeA and MePD, males received unilateral lesions of MeA and MePD within opposite brain hemispheres. Control males received either unilateral lesions of MeA and MePD within the same hemisphere or sham surgery. Odor preferences were measured using a 3-choice apparatus, which simultaneously presented female, male and clean odor stimuli; all tests were done under conditions that either prevented or allowed contact with the odor sources. Under non-contact conditions, males with asymmetrical lesions investigated female and male odors equally, whereas males in both control groups preferred to investigate female odors. Under contact conditions, all groups investigated female odors longer than male odors, although males with asymmetrical lesions displayed decreased investigation of female odors compared to sham males. These data suggest that MeA-MePD interactions are critical for processing primarily the volatile components of social odors and highlight the importance of input from the main olfactory system (MOS) to these nuclei in the regulation of reproductive behavior. More broadly, these results support the role of the MA in integrating chemosensory and hormone information, a process that may underlie
Barnes, D.R.; Ossoff, R.H.; Pecaro, B.; Sisson, G.A.
The problem of mandibular reconstruction has been approached using many surgical techniques. This article studies one such approach--reconstruction using full-thickness clavicle pedicled on the sternocleidomastoid muscle. Five patients with stage II and stage III carcinoma of the anterior part of the floor of the mouth were treated with mandibular resection and neck dissection. The resulting defects were immediately reconstructed with the clavicle-sternocleidomastoid muscle technique. The patients were observed from one to three years and were examined postoperatively with technetium Tc 99m medronate scans, which demonstrated the grafts to be viable. The technique proved reliable in a limited clinical trial.
Almeida, Guilherme de Araújo
ABSTRACT This article reports the clinical case of a female patient with history of unsuccessful orthodontic treatment. She presented with Class III malocclusion, mandibular and maxillary constriction, anterior crossbite and facial asymmetry resulting from laterognathism triggered by hyperactivity of the condyle revealed by vertical elongation of the right mandibular ramus. Patient's treatment consisted of orthodontic mechanics and two orthognathic surgical interventions with satisfactory and stable outcomes. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO), as part of the requirements for obtaining the BBO Diplomate title. PMID:27901236
Lo, Tom Edward Ngo; Villafuerte, Cesar Vincent; Acampado, Laura Trajano
Ameloblastoma is considered to be a benign odontogenic tumour of epithelial in origin that is slow growing but recurrent and invasive in nature. Some of its features have been sources of debate among experts regarding its benign or malignant character. We report a case of a 20-year-old Filipino woman with right mandibular ameloblastoma presenting with overwhelming hypercalcaemia. Work ups for hypercalcaemia eventually revealed tumoral hypercalcaemia, which was initially controlled with intravenous bisphosphanate. The patient eventually underwent tumour excision and mandibular reconstruction, which totally corrected hypercalcaemia. This case will highlight the rare association of hypercalcaemia among patients with ameloblastoma. PMID:25326561
Lo, Tom Edward Ngo; Villafuerte, Cesar Vincent; Acampado, Laura Trajano
Ameloblastoma is considered to be a benign odontogenic tumour of epithelial in origin that is slow growing but recurrent and invasive in nature. Some of its features have been sources of debate among experts regarding its benign or malignant character. We report a case of a 20-year-old Filipino woman with right mandibular ameloblastoma presenting with overwhelming hypercalcaemia. Work ups for hypercalcaemia eventually revealed tumoral hypercalcaemia, which was initially controlled with intravenous bisphosphanate. The patient eventually underwent tumour excision and mandibular reconstruction, which totally corrected hypercalcaemia. This case will highlight the rare association of hypercalcaemia among patients with ameloblastoma. 2014 BMJ Publishing Group Ltd.
Amatoury, Jason; Kairaitis, Kristina; Wheatley, John R; Bilston, Lynne E; Amis, Terence C
Mandibular advancement (MA) increases upper airway (UA) patency and decreases collapsibility. Furthermore, MA displaces the hyoid bone in a cranial-anterior direction, which may contribute to MA-associated UA improvements via redistribution of peripharyngeal tissue stresses (extraluminal tissue pressure, ETP). In the present study, we examined effects of MA on ETP distributions, deformation of the peripharyngeal tissue surface (UA geometry), and hyoid bone position. We studied 13 supine, anesthetized, tracheostomized, spontaneously breathing adult male New Zealand White rabbits. Graded MA was applied from 0 to ∼4.5 mm. ETP was measured at six locations distributed throughout three UA regions: tongue, hyoid, and epiglottis. Axial computed tomography images of the UA (nasal choanae to glottis) were acquired and used to measure lumen geometry (UA length; regional cross-sectional area) and hyoid displacement. MA resulted in nonuniform decreases in ETP (greatest at tongue region), ranging from -0.11 (-0.15 to -0.06) to -0.82 (-1.09 to -0.54) cmH2O/mm MA [linear mixed-effects model slope (95% confidence interval)], across all sites. UA length decreased by -0.5 (-0.8 to -0.2) %/mm accompanied by nonuniform increases in cross-sectional area (greatest at hyoid region) ranging from 7.5 (3.6-11.4) to 18.7 (14.9-22.5) %/mm. The hyoid bone was displaced in a cranial-anterior direction by 0.42 (0.36-0.44) mm/mm MA. In summary, MA results in nonuniform changes in peripharyngeal tissue pressure distributions and lumen geometry. Displacement of the hyoid bone with MA may play a pivotal role in redistributing applied MA loads, thus modifying tissue stress/deformation distributions and determining resultant UA geometry outcomes.
McCarthy, Joseph G; Hopper, Richard A; Hollier, Larry H; Peltomaki, Timo; Katzen, Timothy; Grayson, Barry H
Initial clinical experience with distraction osteogenesis has demonstrated the risk of developing postdistraction malocclusion that requires secondary orthodontic correction. In addition, optimal mandibular form is not always achieved. Both animal studies and preliminary clinical investigations have suggested that the regenerate can be successfully "molded" during active mandibular distraction. The authors have applied this concept clinically to obtain a more desirable occlusal relationship in a group of mandibular distraction patients. Eleven patients are described in whom angulation of the distraction device or intermaxillary/interdental elastics were employed to mold the regenerate. Two representative case studies are provided to illustrate the principles. When using elastic traction to close an anterior open bite, care must be taken that extrusion of individual teeth is minimized by distributing the force over the entire dental arch, especially the basilar portions of the jaws. The authors demonstrate that molding of the regenerate can be successfully accomplished not only during device activation but also early in the consolidation period. The outer limit of the time window in which molding is effective remains to be defined.
Bosio, Jose A; Justus, Roberto
An 8-mm anterior and posterior open bite caused by a tongue rest posture habit was closed in a 25-year-old man by means of mandibular soldered tongue spurs and without orthognathic surgery. All maxillary and mandibular first molars were extracted, and the spaces were closed. Inappropriate retention protocol allowed for relapse in a 6-month period. A new 1-year orthodontic retreatment was conducted; after an appropriate retention protocol, the outcomes of treatment were significantly improved.
Australopithecus robustus has a distinct mandibular anatomy, with a broad and deep corpus and a tall, relatively upright ramus. How this anatomy arose through development is unknown, as gross mandibular size and shape change have not been thoroughly examined quantitatively in this species. Herein, I investigate A. robustus mandibular growth by comparing its ontogenetic series with a sample of recent humans, examining age-related size variation in 28 linear measurements. Resampling is used to compare the amount of proportional size change occurring between tooth eruption stages in the small and fragmentary A. robustus sample, with that of a more complete human skeletal population. Ontogenetic allometry of corpus robusticity is also assessed with least squares regression. Results show that nearly all measurements experience greater average increase in A. robustus than in humans. Most notably, A. robustus corpus breadth undergoes a spurt of growth before eruption of M1 , likely due in part to delayed resorption of the ramus root on the lateral corpus. Between the occlusion of M1 and M2 , nearly all dimensions experience greater proportional size change in A. robustus. Nested resampling analysis affirms that this pattern of growth differences between species is biologically significant, and not a mere byproduct of the fossil sample size. Some species differences are likely a function of postcanine megadontia in A. robustus, although the causes of other differences are less clear. This study demonstrates an important role of the postnatal period for mandibular shape development in this species.
Paolantoni, Guerino; Marenzi, Gaetano; Blasi, Andrea; Mignogna, Jolanda; Sammartino, Gilberto
The purpose of this randomized controlled study is to investigate the clinical results obtained over four years and incidence of complications associated with one- versus two-piece custom made zirconia anchorages, in single tooth implant-supported restorations of the maxillary anterior region. Sixty-five patients, with a total of 74 missing maxillary teeth, were selected in the period from February 2007 to July 2010. Two different ways of custom made zirconia abutment and final prosthetic restoration were evaluated: a standard zirconia abutment associated with a pressed layer of lithium disilicate with an all-ceramic cemented restoration versus one-piece restoration with the facing porcelain fired and pressed straight to the custom made zirconia abutment. In 29 cases, the restoration consisted of an all-ceramic restoration for cementation (two pieces); in 45 cases the restoration was a screw-retained restoration (one piece). Three all-ceramic restorations broke during the observation time. Two one-piece restorations fractured after 26 months. At follow-up examination there were no significant differences between one-piece and two-piece groups regarding the PI, BI, and MBL. Awaiting studies with longer follow-up times, a careful conclusion is that zirconia anchorages for single-implant restorations seem to demonstrate good short-term technical and biological results. PMID:27027093
Fu, Qian; Xie, Mingxing; Wang, Jing; Wang, Xinfang; Lv, Qing; Lu, Xiaofang; Fang, Lingyun; Chang, Long
This study evaluated the change in regional left ventricular myocardial function in rats following acute occlusion of the left anterior descending coronary artery (LAD) by using two-dimensional speckle tracking imaging (2D-STI). Sixty Wistar rats were randomly divided into two groups, a myocardial infarction (MI) group, in which 50 rats were subjected to LAD occlusion for 30-45 min, and a sham-operated (SHAM) group that contained 10 rats serving as control. Echocardiography was performed at baseline and 1, 4 and 8 week(s) after the operation. High frequency two-dimensional images of left ventricular short axis at papillary muscle level were recorded. Peak systolic radial strain (PRS) and circumferential strain (PCS) were measured in the mid-ventricle in short-axis view by using EchoPAC workstation. Left ventricular internal diameter at diastole (LVIDd) and systole (LVIDs), fractional shortening (FS), ejection fraction (EF) and left ventricular mass (LVM) were measured by anatomical M-model echocardiography. Infarct size was measured using triphenyl tetrazolium chloride (TTC) staining 1 week and 8 weeks after the operation. Fibrosis of left ventricular myocardium was displayed using Van Gieson staining 1 week after the infarction. In terms of the TTC staining results, the left ventricle fell into three categories: infarcted, peri-infarcted and remote myocardial regions. Compared with those at baseline and in the SHAM group, (1) PRS and PCS in the infarcted, peri-infarcted and remote myocardial regions were significantly decreased in the MI group within 1 week after the operation (P<0.05) and the low levels lasted 8 weeks; (2) Compared with those at baseline, LVIDd, LVIDs, FS, EF and LVM in the MI group showed no significant difference 1 week after the operation (P>0.05). However, LVIDd, LVIDs and LVM were increased significantly 4 and 8 weeks after the operation (P<0.05), and FS and EF were decreased substantially (P<0.05). Van Gieson staining showed that fibrosis
Kalantar Motamedi, Mahmood Reza; Heidarpour, Majid; Siadat, Sara; Kalantar Motamedi, Alimohammad; Bahreman, Ali Akbar
Extraction of mandibular third molars (M3s) in close proximity to the mandibular canal has some inherent risks to adjacent structures, such as neurologic damage to teeth, bone defects distal to the mandibular second molar (M2), or pathologic fractures in association with enlarged dentigerous cysts. The procedure for extrusion and subsequent extraction of high-risk M3s is called orthodontic extraction. This is a systematic review of the available approaches for orthodontic extraction of impacted mandibular M3s in close proximity to the mandibular canal and their outcomes. The PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), DOAJ, Google Scholar, OpenGrey, Iranian Science Information Database (SID), Iranmedex, and Irandoc databases were searched using specific keywords up to June 2, 2014. Studies were evaluated based on predetermined eligibility criteria, treatment approaches, and their outcomes. Thirteen articles met the inclusion criteria. A total of 123 impacted teeth were extracted by orthodontic extraction and 2 cases were complicated by transient paresthesia. Three types of biomechanical approaches were used: 1) using the posterior maxillary region as the anchor for orthodontic extrusion of lower M3s, 2) simple cantilever springs attached to the M3 buttonhole, and 3) cantilever springs tied to a bonded orthodontic bracket on the M3 plus multiple-loop spring wire for distal movement of the M3. Osteo-periodontal status of M2s also improved uneventfully. Despite the drawbacks of orthodontic extraction, removal of deeply impacted M3s using the described techniques is safe with regard to mandibular nerve injury and neurologic damage. Orthodontic extraction is recommended for extraction of impacted M3s that present a high risk of postoperative osteo-periodontal defects on the distal surface of the adjacent M2 and those associated with dentigerous cysts. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by
Ellis, E; Gallo, W J
This study examines the short-term stability of the mandible following mandibular advancement surgery in which skeletal suspension wires were used in addition to dental maxillomandibular fixation. Twenty adults underwent sagittal ramus osteotomies. No concomitant surgical procedures were performed. Maxillomandibular fixation consisted of wiring between the upper and lower orthodontic brackets and circummandibular wires connected to the piriform aperture or anterior nasal spine wires for eight weeks. Cephalograms were analyzed during this period to evaluate skeletal stability. A statistically insignificant mean horizontal relapse of 8.9% was found at pogonion during the period of fixation. Significant vertical intrusion of the anterior mandible occurred, however, with a mean superior movement of pogonion of 0.83 mm (P less than or equal to 0.05). Dental changes noted were uprighting of the maxillary incisors and flaring of the mandibular incisors. In comparison with the results of other studies in which dental maxillomandibular fixation was used alone, the results of this study indicate that the use of skeletal suspension wires is advantageous in the prevention of horizontal skeletal relapse.
Dentures were fabricated for a 73-year-old woman using porcelain 20-degree maxillary posterior teeth and acrylic resin flat planes in the mandibular posterior region. A digital gothic arch tracing device was used to observe the horizontal mandibular positions before insertion and to evaluate the therapeutic effect of the diagnostic dentures at 1 and 3 months after insertion.
El-Bialy, Tarek; Alhadlaq, Adel; Felemban, Nayef; Yeung, Jasper; Ebrahim, Amal; Hassan, Ali H
To evaluate the effect of a light-emitting diode (LED) and/or low-level laser (LLL) with or without the use of anterior bite jumping appliances (also known as functional appliances [FAs]) on mandibular growth in rats. Thirty-six 8-week-old male Sprague-Dawley rats weighing 200 g were obtained from Charles River Canada (St. Constant, QC, Canada) and were divided into six groups of six animals each. Groups were as follows: group 1: LLL; group 2: LLL + FA; group 3: LED; group 4: LED + FA; group 5: FA; and group 6: control (no treatment). Mandibular growth was evaluated by histomorphometric and micro computed tomographic (microCT) analyses. The LED and LED + FA groups showed an increase in all condylar tissue parameters compared with other groups. The LED-treated groups showed more mandibular growth stimulation compared with the laser groups.
Sachdeva, Suresh K; Verma, Pradhuman; Dutta, Sanjay; Verma, Kanika Gupta
Talon cusp is a relatively rare developmental dental anomaly thought to arise as a result of evagination on the surface of a tooth crown before calcification has occurred. It is characterized by cusp-like projections from the cingulum area, or cemento-enamel junction of maxillary or mandibular anterior teeth, in both the primary and permanent dentition, usually observed on the lingual surface of the affected tooth. The cusp may or may not contain an extension of the pulp. The etiology remains unknown. The incidence is 0.04-8%. Any tooth may have a talon cusp but most of the cases involve maxillary lateral incisors. The anomaly has been reported to be rare especially when it occurs on mandibular teeth. This article reports a case of talon cusp on permanent mandibular central incisor that too on facial aspect which makes it a rare entity.
Oredugba, Folakemi A
Talon cusp is a supernumerary structure projecting from the dento-enamel junction to a variable distance towards the incisal edge of an anterior tooth. Studies have shown that it consists of enamel, dentine and a variable amount of pulp tissue. Hyperactivity of the enamel organ during morphodifferentiation has been attributed to its formation. Most previous reports have been made concerning the occurrence of this structure on primary and permanent teeth and mostly on the palatal aspect. Only few have been reported on the facial aspect of the teeth. When it occurs, the effects are mainly aesthetic and functional and so early detection and treatment is essential in its management to avoid complications. An unusual case of talon cusp on the facial aspect of a mandibular central incisor is reported. Its presence resulted in attrition of the opposing tooth. Reduction of the cusp and topical application of fluoride gel was initiated. The management and treatment outcome of talon cusp depends on the size, presenting complications and patient cooperation.
Gökçen-Röhlig, Bilge; Atalay, Belir; Baca, Emrah; Işik, Deniz; Meriç, Uğur
Injuries to the orofacial region may vary from localized injuries to extensive soft and hard tissue loss. In addition to physical and psychologic damages, functional and aesthetic aspects must be restored. This clinical report describes the rehabilitation of a patient with a mandibular defect caused by a gunshot wound. Rehabilitation of this patient, with the use of an overdenture prosthesis, was performed after mandibular surgical hard and soft tissue reconstruction. A maxillary total prosthesis and an implant-supported mandibular overdenture supported by 4 osseointegrated implants were fabricated. Despite limited mouth opening and anatomic deficiencies, the patient's aesthetic and functional demands were fulfilled.
Jing, Yan; Han, Xianglong; Guo, Yongwen; Li, Jingyu; Bai, Ding
This article reports the successful use of miniscrews in the mandible to treat a 20-year-old Mongolian woman with a chief complaint of anterior crossbite. The patient had a skeletal Class III malocclusion with a mildly protrusive mandible, an anterior crossbite, and a deviated midline. In light of the advantages for reconstruction of the occlusal plane and distal en-masse movement of the mandibular arch, we used a multiloop edgewise archwire in the initial stage. However, the maxillary incisors were in excessive labioversion accompanied by little retraction of the mandibular incisors; these results were obviously not satisfying after 4 months of multiloop edgewise archwire treatment. Two miniscrews were subsequently implanted vertically in the external oblique ridge areas of the bilateral mandibular ramus as skeletal anchorage for en-masse distalization of the mandibular dentition. During treatment, the mandibular anterior teeth were retracted about 4.0 mm without negative lingual inclinations. The movement of the mandibular first molar was almost bodily translation. The maxillary incisors maintained good inclinations by rotating their brackets 180° along with the outstanding performance of the beta-titanium wire. The patient received a harmonious facial balance, an attractive smile, and ideal occlusal relationships. The outcome was stable after 1 year of retention. Our results suggest that the application of miniscrews in the posterior area of the mandible is an effective approach for Class III camouflage treatment. This technique requires minimal compliance and is particularly useful for correcting Class III patients with mild mandibular protrusion and minor crowding. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.
Nagadia, R; Tay, A B G; Chan, L L; Chan, E S-Y
The inferior alveolar nerve (IAN) is vulnerable to injury from mandible fractures and surgical procedures so anatomical variations of IAN are important. Postoperative sensory alteration of the lip and chin region is high after mandibular orthognathic surgery. The incidence of IAN paresthesia following sagittal split ramus osteotomy (SSRO) ranges from 54% to 86% at 4-8 days, 41 to 75% at 1 month, 33 to 66% at 3 months, 17 to 58% at 6 months and 15 to 33% at 1 year postoperatively. This study determined the anatomical position of the mandibular canal in relation to cortical bone and molar teeth in Chinese using archived CT records. The mandibular canal was the farthest from the buccal cortex at the second molar region (mean 6.79mm; minimum distance 4.80mm). The anatomical location of the mandibular canal in local Chinese compares with studies on Asian cadavers. The mandible body was thickest in the region of the second molar (11.9mm). The vertical buccal cut for SSRO should be in the region of the mandibular second molar where the bone is thickest and the mandibular canal is furthest from the buccal cortex. The safe depth for the vertical buccal cut is 4.8mm (minimum horizontal distance).
Kim, Dae Hyun; Kim, Moon Yong
Objectives The interforminal region, between the mandibular foramen, is known as a relatively safe area that is free of anatomic structures, such as inferior alveolar nerve, submandibular fossa, and lingual side of the mandible is occasionally neglected for its low clinical importance. Even in the case of a severely constricted alveolus, perforation of the lingual cortical bone had been intended. However, anterior extension of the inferior alveolar canal, important anatomic structure, such as concavity of lingual bone, lingual foramina, and lingual canal, has recently been reported through various studies, and untypical bleeding by perforation of the lingual plate on implantation has also been reported. Therefore, in this study, we performed radiographic and statistical analysis on distribution and appearance frequencies of the lingual foramina that causes perforation of the mandibular lingual cortical bone to prevent complications, such as untypical bleeding, during surgical procedure. Materials and Methods We measured the horizontal length from a midline of the mandible to the lingual foramina, as well as the horizontal length from the alveolar crest to the lingual foramina and from the lingual foramina to the mandibular border by multi-detector computed tomography of 187 patients, who visited Dankook University Dental Hospital for various reasons from January 1, 2008 to August 31, 2012. Results From a total of 187 human mandibles, 110 (58.8%) mandibles had lingual foramina; 39 (20.9%) had bilateral lingual foramen; 34 (18.2%) had the only left lingual foramen; and 37 (19.8%) had the only right lingual foramen. Conclusion When there is consistent bleeding during a surgical procedure, clinicians must consider damages on the branches of the sublingual artery, which penetrate the lingual foramina. Also, when there is a lingual foramina larger than 1 mm in diameter on a pre-implantation computed tomography, clinicians must beware of vessel damage. In order to prevent
Green, Jordan R; Wilson, Erin M; Wang, Yu-Tsai; Moore, Christopher A
The movement of the jaw during speech and chewing has frequently been studied by tracking surface landmarks on the chin. However, the extent to which chin motions accurately represent those of the underlying mandible remains in question. In this investigation, the movements of a pellet attached to the incisor of the mandible were compared with those of pellets attached to different regions of the chin. Ten healthy talkers served as participants. Three speaking contexts were recorded from each participant: word, sentence, and paragraph. Chin position errors were estimated by computing the standard distance between the mandibular incisor pellet and the chin pellets. Relative to the underlying mandible, chin pellets moved with an average absolute and relative error of 0.81 mm and 7.30%, respectively. The movements of chin and mandibular pellets were tightly coupled in time. The chin tracking errors observed in this investigation are considered acceptable for descriptive studies of oromotor behavior, particularly in situations where mandibular placements are not practical (e.g., young children or edentulous adults). The observed amount of error, however, may not be tolerable for fine-grained analyses of mandibular biomechanics. Several guidelines are provided for minimizing error associated with tracking surface landmarks on the chin.
Lim, William; Weng, Lye Kok; Tin, Goh Bee
Osteochondromas are common tumors of the long bones, but are rare in the craniofacial region. We detailed two different management of osteochondroma of the mandibular condyle treated utilizing three-dimensional (3D) imaging and computer-assisted planning. Simultaneous open temporomandibular joint and orthognathic surgeries were done to treat both the pathology and secondary facial asymmetry. An osteochondroma that presented as a bony mass at the lateral aspect of the left mandibular condyle of a 24-year-old Chinese female was treated with simultaneous orthognathic surgery and conservative excision. No recurrence was detected 7 months postsurgery. An osteochondroma that presented as a generalized enlargement of the right mandibular condyle of a 25-year-old Chinese male was treated with simultaneous orthognathic surgery and condylectomy. There were no significant issues 3 years postsurgery. Simultaneous orthognathic and temporomandibular joint surgeries are a viable option for the management of osteochondroma of the mandibular condyle. The availability of 3D imaging enabled better presurgical examination of the lesion, which directed treatment toward condylectomy or conservative excision. PMID:25593879
Green, Jordan R.; Wilson, Erin M.; Wang, Yu-Tsai; Moore, Christopher A.
Purpose The movement of the jaw during speech and chewing has frequently been studied by tracking surface landmarks on the chin. However, the extent to which chin motions accurately represent those of the underlying mandible remains in question. In this investigation, the movements of a pellet attached to the incisor of the mandible were compared with those of pellets attached to different regions of the chin. Method Ten healthy talkers served as participants. Three speaking contexts were recorded from each participant: word, sentence, and paragraph. Chin position errors were estimated by computing the standard distance between the mandibular incisor pellet and the chin pellets. Results Relative to the underlying mandible, chin pellets moved with an average absolute and relative error of 0.81 mm and 7.30%, respectively. The movements of chin and mandibular pellets were tightly coupled in time. Conclusion The chin tracking errors observed in this investigation are considered acceptable for descriptive studies of oromotor behavior, particularly in situations where mandibular placements are not practical (e.g., young children or edentulous adults). The observed amount of error, however, may not be tolerable for fine-grained analyses of mandibular biomechanics. Several guidelines are provided for minimizing error associated with tracking surface landmarks on the chin. PMID:17675597
Creugers, N. H. J.; Witter, D. J.; Van 't Spijker, A.; Gerritsen, A. E.; Kreulen, C. M.
Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n = 25) were compared with subjects with shortened dental arches without extension (n = 74) and with subjects who had worn a mandibular extension removable partial denture in the past (n = 19). Subjects with complete dentitions (n = 72) were controls. Data were collected at baseline and at 3-, 6-, and 9-year observations. Results. Occlusal activity in terms of reported awareness of bruxism and occlusal tooth wear of lower anterior teeth did not differ significantly between the groups. In contrast, occlusal tooth wear of premolars in shortened dental arches with or without extension dentures was significantly higher than in the controls. Differences amongst groups with respect to signs and symptoms related to temporomandibular disorders were not found. Occlusal support of the dentures did not influence anterior spatial relationship. Occlusal contacts of the denture teeth decreased from 70% for second premolars via 50% for first molars, to 30% for second molars. Conclusions. Mandibular distal extension removable partial dentures in moderate shortened dental arches had no effects on occlusion and temporomandibular function. PMID:20671961
Geng, Bin; Wang, Jing; Ma, Jing-Lin; Zhang, Bo; Jiang, Jin; Tan, Xiao-Yi; Xia, Ya-Yi
Background: Few data are available concerning intercondylar notch dimensions in female nonathletes with knee osteoarthritis (OA) in plateau region. The aim of this study was to assess the relation of intercondylar notch morphology to anterior cruciate ligament (ACL) injuries in female nonathletes with knee OA aged 41–65 years from the Chinese Loess Plateau. Methods: The study was conducted on 330 patients with ACL injury (aged 31–65 years; 159 males, 171 females), 141 patients with OA (aged 31–65 years; 59 males, 82 females), and 89 female healthy controls (aged 41–65 years), and this evaluation included identifying the distribution of patients with OA or ACL injury and measuring the intercondylar notch width indexes (NWIs). Results: There was a significant rising trend in patients with OA (the Kellgren and Lawrence grade = 3) with ACL injury (OA-S + ACL) aged 41–65 years, especially in females. We found that the notches of OA-S + ACL had a smaller NWI compared with control and OA without ACL injury (OA-S-only, P = 0.000, 95% confidence interval [CI] = −0.059–−0.030; P = 0.000, 95% CI = −0.049–−0.016). A similar trend was found in notch shape index (NSI), but not in notch depth index and the cross-sectional area. The cutoff of NWI and NSI value was 0.26, and 0.65, and area under the receiver operating characteristic curve was 0.82, and 0.79, respectively. Further study displayed a significant correlation between a reduced NWI and NSI and OA-S + ACL (P = 0.000, χ2 = 14.012; P = 0.000, χ2 = 14.286). Conclusion: A narrower intercondylar notch and a plateau environment are risk factors of predisposing female nonathletes with knee OA to ACL injury aged 41–65 years. PMID:27779159
Borie, Eduardo; Orsi, Iara Augusta; Noritomi, Pedro Yoshito; Kemmoku, Daniel Takanori
To evaluate the biomechanical behaviors of multiple implant-supported prostheses with different implant lengths, connections, locations, and restoration materials in the maxillary anterior region using three-dimensional finite element analysis. A finite element model of a maxillary image was created from a tomography data bank. The simulations were executed in two types of models based on the treatment plan: (1) two implants with 4.0-mm diameters placed in the maxillary central incisors to simulate an implant-supported fixed prosthesis with four elements with a cantilever of both maxillary lateral incisors; (2) two implants with 3.75-mm diameters placed in the maxillary lateral incisors to simulate a conventional fixed prosthesis with four elements with pontics for maxillary central incisors. Subsequently, the models created were subdivided into eight subgroups according to implant length, connection type, and restoration material. A total static oblique load of 150 N was applied to the cingulum area of the palatal surfaces of the four incisors at an angle of 45 degrees to the long axis of the implant in the palatal-labial direction. Bone stresses were analyzed through maximum and minimum principal stresses and ductile material as implant, framework, and abutments were analyzed using von Mises stress criterion. Regardless of implant diameter and type of treatment, the 8.5-mm-long implants exhibited the lowest tensile and compressive stresses. Maximum and minimum principal stresses were identified in the cortical bone. The lowest von Mises equivalent stress values were identified in the metal-ceramic prostheses, with the exception of the cantilever prosthesis model with flat top connection. Conical cone implant models exhibited maximum von Mises equivalent stress in contact with the abutment. The lowest principal stresses in the peri-implant bone were observed in implants with conical cone connection and 8.5 mm in length. Also, in most cases, the models with metal
Nayak, US Krishna; Hegde, Gautam
Background and objectives Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. Methods A total of 160 periapical radiographs (80 males and 80 females), of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian’s stages of dental calcification and the modified MP3 stages. Results The correlation between the developmental stages of MP3 and the mandibular right canine in male and female groups, is of high statistical significance (p = 0.001). The correlation coefficient between MP3 stages and developmental stages of mandibular canine and chronological age in male and females was found to be not significant. Conclusions The correlation between the mandibular canine calcification stages and MP3 stages was found to be significant. The developmental stages of the mandibular canine could be used very reliably as a sole indicator for assessment of skeletal maturity. PMID:27625553
Nayak, Reshma; Nayak, Us Krishna; Hegde, Gautam
Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. A total of 160 periapical radiographs (80 males and 80 females), of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian's stages of dental calcification and the modified MP3 stages. The correlation between the developmental stages of MP3 and the mandibular right canine in male and female groups, is of high statistical significance (p = 0.001). The correlation coefficient between MP3 stages and developmental stages of mandibular canine and chronological age in male and females was found to be not significant. The correlation between the mandibular canine calcification stages and MP3 stages was found to be significant. The developmental stages of the mandibular canine could be used very reliably as a sole indicator for assessment of skeletal maturity.
Koshy, John C.; Feldman, Evan M.; Chike-Obi, Chuma J.; Bullocks, Jamal M.
Mandibular trauma is a common problem seen by plastic surgeons. When fractures occur, they have the ability to affect the patient's occlusion significantly, cause infection, and lead to considerable pain. Interventions to prevent these sequelae require either closed or open forms of reduction and fixation. Physicians determining how to manage these injuries should take into consideration the nature of the injury, background information regarding the patient's health, and the patient's comorbidities. Whereas general principles guide the management of the majority of injuries, special consideration must be paid to the edentulous patient, complex and comminuted fractures, and pediatric patients. These topics are discussed in this article, with a special emphasis on pearls of mandibular trauma management. PMID:22550460
Davis, Jillian S; Nicolay, Christopher W; Williams, Susan H
The three species of vampire bats (Phyllostomidae: Desmodontinae), Desmodus rotundus, Diaemus youngi, and Diphylla ecaudata, are the only mammals that obtain all nutrition from vertebrate blood (sanguinivory). Because of the unique challenges of this dietary niche, vampire bats possess a suite of behavioral, physiological, and morphological specializations. Morphological specializations include a dentition characterized by small, bladelike, non-occlusive cheek teeth, large canines, and extremely large, procumbent, sickle-shaped upper central incisors. The tips of these incisors rest in cuplike pits in the mandible behind the lower incisors (mandibular pits). Here, we use microCT scanning and high-resolution radiography to describe the morphology of the mandible and anterior dentition in vampire bats, focusing on the relationship between symphyseal fusion, mandibular pit size, incisor size, and procumbency. In Desmodus and Diaemus, highly procumbent upper incisors are associated with relatively small mandibular pits, an unfused mandibular symphysis with substantial bony interdigitations linking the dentaries, and a diastema between the lower central incisors that helps to facilitate the lapping of blood from a wound. In Diphylla, less procumbent upper incisors are associated with relatively large mandibular pits, a completely fused mandibular symphysis, and a continuous lower toothrow lacking a central diastema. We hypothesize that symphyseal morphology and the presence or absence of the diastema are associated with the angle of upper incisor procumbency and mandibular pit development, and that spatial constraints influence the morphology of the symphysis. Finally, this morphological variation suggests that Diphylla utilizes a different feeding strategy as compared to Desmodus and Diaemus, possibly resulting from the functional demands of specialization on avian, rather than mammalian, blood.
Halicioglu, Koray; Celikoglu, Mevlut; Buyuk, Suleyman K.; Sekerci, Ahmet E.; Candirli, Celal
Objective: The objective of the following study is to investigate the mandibular vertical asymmetry in a group of patients with early unilateral mandibular first molar extractions. Materials and Methods: Mandibular asymmetry index measurements (condylar, ramal and condylar-plus-ramal) were performed on the panoramic radiographs of a study group including 51 patients (mean age: 18.60 ± 1.11 years) and a control group of 51 patients (mean age: 18.53 ± 1.29 years). Group I included patients with a unilateral mandibular first molar extracted before the age of 12 years. Group II included patients with no extractions and had excellent Class I relationships, no missing teeth and slight or moderate anterior crowding. A paired t-test was used to determine possible statistically significant differences between the sides for the measurements. Student's t-test was used for the comparison of asymmetry index values between the groups and genders. Results: No group showed statistically significant sex-or side-specific differences for posterior vertical height measurements. Condylar asymmetry index and ramal asymmetry index measurements were not statistically different between the groups, while condylar-plus-ramal asymmetry index (CRAI) measurements were statistically different between the groups (P = 0.019). Conclusions: A slight difference for CRAI value was found in patients with early unilateral mandibular first molar extractions. PMID:24966767
Leser, Casey P; Jepsen, Shawn A
Performing surgical procedures on the mandible can present many challenges due to the anatomy and the limited access available to the various areas of the mandibular arch. The experience of the surgeon and the complexity of the surgery must be considered before attempting treatment. A static mandibular training model provides dentists with the opportunity to practice multiple surgical procedures to develop the skills that are necessary to treat patients competently and comprehensively. The mandible's unique anatomy presents a number of challenges when performing surgical procedures. A surgical model that makes it possible to practice multiple techniques benefits the surgeon by building the confidence to attempt more complex surgical procedures and thus provide patients with additional treatment options. This mandibular surgical model serves as a learning tool and provides an avenue for learning different surgical techniques that may be performed in various areas of the mandible. A number of procedures can be performed on the model, including the extraction of third molars, incision and drainage of a vestibular/buccal swelling, excisional biopsy of intrabony lesions, tori removal, initial implant alignment procedures, and suturing/flap designs. A number of these procedures can be performed on one model.
Agrawal, Aditi; Manjunatha, Bhari Shranesha; Dholia, Bhavik; Althomali, Yousef
Background and Objectives: Sexual dimorphism is one of important tool of forensic science. The objective of this study is to assess the dimorphic status of mesio-distal (MD) and bucco-lingual (BL) diameter of mandibular canine with mandibular first molar among the students of dental college. This study is of definite significance as sex chromosomes and hormonal production influenced tooth morphology. Materials and Methods: The descriptive study adopted the purposive sampling technique, of 50 male and 50 female aged 17-25 years, using study casts for mesio-distal and bucco-lingual dimensions of mandibular canine with mandibular first molar were taken using digital Vernier caliper. The data obtained were subjected to statistical analysis using descriptive statistics and t-test to compare MD and BL dimensions in male and female populations and P ≤ 0.05 was found statistically significant. Results: Sexual dimorphism can be predicted by measuring mesiodistal dimension of mandibular canine and mandibular first molar. The left mandibular canine showed more sexual dimorphism (12.66%) in comparison to left mandibular first molar (0.824%) only. Right mandibular canine showed greater dimorphism in MD dimensions (10.94%) in comparison to right mandibular first molar (6.96%). In bucco-lingual dimensions mandibular canine showed less variability when compared with mandibular first molar, thus our study showed more significance on mesio-distal dimensions of both teeth. Conclusion: The present study concludes statistically significant sexual dimorphism in mandibular canine over mandibular first molar on study casts. The MD dimensions in mandibular canine and mandibular first molar can help in determining sex and identification of unknown person. PMID:26816466
Samman, N; Luk, W K; Chow, T W; Cheung, L K; Tideman, H; Clark, R K
Reconstruction of the mandible after ablative surgery can be achieved by using preformed trays or trays formed from models produced by computer-assisted modelling systems. The former presents difficulty in matching the required facial contour, jaw relationship and condylar position; while the latter is expensive. This paper presents a simple and inexpensive method of fabricating a custom-made titanium bone grafting tray. The dimensions of the patient's mandible are obtained by clinical measurement. Such measurements are used to construct a mandibular replica. The region to be reconstructed is carved to produce the ideal shape and dimensions of an edentulous segment. The tray is made either by casting or by swaging. Twenty-one custom-made titanium bone grafting trays have been fitted in patients with encouraging results. This method of bone grafting tray construction is a simple, inexpensive technique for achieving excellent facial contour and functional reconstruction after mandibulectomy.
Gandhi, Yazad R
Dystonia is an involuntary, repetitive, sustained (tonic), or spasmodic (rapid or clonic) muscle contraction. The spectrum of dystonias can involve various regions of the body. Oromandibular dystonia (OMD) can involve the masticatory, lower facial and the tongue muscles which may results in trismus, bruxism, involuntary jaw opening or closure and involuntary tongue movement. Here, we report a case of OMD in a 68 year old man.
Elsalanty, Mohammed E; Taher, Taher N; Zakhary, Ibrahim E; Al-Shahaat, Osama A; Refai, Mohammed; El-Mekkawi, Hatem A
Reconstruction of large anterior mandibular defects is a challenging task. The condition can become even more complex if primary reconstruction fails, leading to loss of the entire midline portion of the lower face with massive scarring of the remaining tissues. Bone transport distraction osteogenesis can provide a viable treatment option for these patients. One of such cases will be presented, followed by a discussion of the advantages, disadvantages, and limitations of the technique.
Kavitha, Swaminathan; Selvakumar, Haridoss; Barathan, Rajendran
A talon cusp is a dental anomaly commonly occurring in the permanent dentition compared to the primary dentition. It commonly affects the maxillary anterior teeth. In primary dentition, the most commonly affected tooth is the maxillary central incisors. This is a rare case report of a 5-year-old male patient with a talon cusp affecting the mandibular primary lateral incisor. Recognition and treatment of this anomaly at early stages is important to avoid complications.
Canger, Emin Murat; Çelenk, Peruze; Bulut, Emel; Günhan, Ömer
To report a small intaalveolar ameloblastoma which resembled cystic lesion, and to emphasize the value of Computed tomography (CT) in radiographic examination. Ameloblastoma is a slow-growing, locally invasive odontogenic neoplasm that accounts for approximately 10% of all tumors detected in the jaws. Radiographically, those tumors are usually well-defined. Computerized tomography is highly recommended to confirm the diagnosis. A 48-year-old female attended with a chief complaint of painless swelling in the left anterior of mandible, 1 month duration. In intraoral examination, non-fluctuant, immobile, approximately 1 × 1 cm in dimension, painless, swelling which had a bone-like hardness and located in the mandibular canine region was detected. Panoramic radiography revealed a well circumscribed unilocular radiolucent lesion located in the inter-radicular area of left mandibular lateral and canine teeth. In CT examination it was realized that the lesion was multilocular. Histopathological examination of the biopsy specimen was reported as ameloblastoma. It is extremely difficult to find such an ameloblastoma in small dimension in alvolar bone.
... device that is intended to stabilize mandibular bone and provide for temporary reconstruction of the... surgical procedures requiring removal of the mandibular condyle and mandibular bone. This device is not...
Kenkel, Jeffrey M; Jones, Derek H; Fagien, Steven; Glaser, Dee Anna; Monheit, Gary D; Stauffer, Karen; Sykes, Jonathan M
In 2015, ATX-101 (deoxycholic acid injection; Kybella in the United States and Belkyra in Canada; Kythera Biopharmaceuticals, Inc., Westlake Village, CA [an affiliate of Allergan plc, Dublin, Ireland]) was approved as a first-in-class injectable drug for reduction of submental fat. Use of a pharmacologic/injectable therapy within the submental region requires a thorough understanding of cervicomental anatomy to ensure proper injection technique and safe administration. To this end, an anatomy laboratory was conducted to review key external landmarks and important internal anatomic structures that characterize the lower face and anterior neck. External landmarks that define the boundaries of the cervicomental and submental regions were identified including the inferior mandibular border, the anterior border of the sternocleidomastoid muscle, the antegonial notch, the submental crease, the thyroid notch, and the hyoid bone. Relevant internal anatomic structures, including preplatysmal submental fat (the target tissue for ATX-101) and the platysma muscle as well as critical neurovascular and glandular tissues were revealed by dissection. Of particular interest was the marginal mandibular branch of the facial nerve because it typically courses along the inferior mandibular border near the proposed treatment area for ATX-101.
Arzi, Boaz; Cissell, Derek D.; Pollard, Rachel E.; Verstraete, Frank J. M.
Extensive rostral mandibulectomy in dogs typically results in instability of the mandibles that may lead to malocclusion, difficulty in prehension, mastication, and pain of the temporomandibular joint. Large rostral mandibular defects are challenging to reconstruct due to the complex geometry of this region. In order to restore mandibular continuity and stability following extensive rostral mandibulectomy, we developed a surgical technique using a combination of intraoral and extraoral approaches, a locking titanium plate, and a compression resistant matrix (CRM) infused with rhBMP-2. Furthermore, surgical planning that consisted of computed tomographic (CT) scanning and 3D model printing was utilized. We describe a regenerative surgical technique for immediate or delayed reconstruction of critical-size rostral mandibular defects in five dogs. Three dogs had healed with intact gingival covering over the mandibular defect and had immediate return to normal function and occlusion. Two dogs had the complication of focal plate exposure and dehiscence, which was corrected with mucosal flaps and suturing; these dogs have since healed with intact gingival covering over the mandibular defect. Mineralized tissue formation was palpated clinically within 2 weeks and solid bone formation within 3 months. CT findings at 6 months postoperatively demonstrated that the newly regenerated mandibular bone had increased in mineral volume with evidence of integration between the native bone, new bone, and CRM compared to the immediate postoperative CT. We conclude that rostral mandibular reconstruction using a regenerative approach provides an excellent solution for restoring mandibular continuity and preventing mandibular instability in dogs. PMID:26664933
Tassopoulou-Fishell, Maria; Deeley, Kathleen; Harvey, Erika M.; Sciote, James; Vieira, Alexandre R.
Introduction Several candidate loci have been suggested as influencing mandibular prognathism (1p22.1, 1p22.2, 1p36, 3q26.2, 5p13-p12, 6q25, 11q22.2-q22.3, 12q23, 12q13.13, and 19p13.2). The goal of this study was to replicate these results in a well-characterized homogeneous sample set. Methods Thirty-three single nucleotide polymorphisms spanning all candidate regions were studied in 44 prognathic and 35 Class I subjects from the University of Pittsburgh School of Dental Medicine Dental Registry and DNA Repository. The 44 mandibular prognathism subjects had an average age of 18.4 years, 31 were females and 13 males, and 24 were White, 15 African American, two Hispanic, and three Asian. The 35 Class I subjects had an average age of 17.6 years, 27 were females and 9 males, and 27 were White, six African Americans, one Hispanic, and two Asian. Skeletal mandibular prognathism diagnosis included cephalometric values indicative of Class III such as ANB smaller than two degrees, negative Witts appraisal, and positive A–B plane. Additional mandibular prognathism criteria included negative OJ and visually prognathic (concave) profile as determined by the subject's clinical evaluation. Orthognathic subjects without jaw deformations were used as a comparison group. Mandibular prognathism and orthognathic subjects were matched based on race, sex and age. Genetic markers were tested by polymerase chain reaction using TaqMan chemistry. Chi-square and Fisher exact tests were used to determine overrepresentation of marker allele with alpha of 0.05. Results An association was unveiled between a marker in MYO1H (rs10850110) and the mandibular prognathism phenotype (p=0.03). MYO1H is a Class-I myosin that is in a different protein group than the myosin isoforms of muscle sarcomeres, which are the basis of skeletal muscle fiber typing. Class I myosins are necessary for cell motility, phagocytosis and vesicle transport. Conclusions More strict clinical definitions may increase
Gadicherla, Srikanth; Sasikumar, Prem; Gill, Satpal Singh; Bhagania, Manish; Kamath, Abhay Taranath; Pentapati, Kalyana Chakravarthy
Objectives The aim of this study was to evaluate the distribution, etiology and type of mandibular fractures in subjects referred to our institution. Methods A retrospective study of 689 subjects, during the period from May 2010 to September 2013 with mandibular fractures was conducted. Information on age, gender, mechanism of injury and sites of trauma was obtained from the trauma registry. Data were tabulated and analyzed statistically. Results A total of 653 subjects had mandibular fractures, out of which 574 were males. The mean age of the participants was 31.54 ± 13.07. The majority of the subjects were between 21-40 years of age, in both males (61.7%) and females (54.4%). The major cause of fractures was road traffic accidents (87.4%) followed by fall (6.9%) and assault (4%), with the least frequent being gunshot injuries (0.3%). Almost half of the patients had parasymphysis fractures (50.2%), followed by angle (24.3%), condyle (20.4%), ramus (2.3%) and coronoid (2%). A total of 115 patients had bilateral fractures out of which 29 had parasymphysis, 12 had body fractures and 74 had bilateral condylar fractures. Double mandibular fractures were reported in 193 subjects; out of which 151 subjects had double contralateral and 42 had double unilateral fractures. Triple unilateral fracture was reported in only one subject. A total of 338 subjects had multiple fractures among the study population. Conclusions Mandibular fractures can be complicated and demanding, and have a compelling impact on patients’ quality of life. Our study reported that parasymphysis was the most common region involved in mandible fractures. PMID:28144599
Adenomatoid odontogenic tumor (AOT) is a rare, benign odontogenic tumor that predominantly appears in the second decade of life in female patients. Most AOTs occur in the anterior part of the maxilla and are usually associated with impacted anterior teeth. There are three types of AOT, follicular, extrafollicular, and peripheral, which are classified based on the location of the lesion and its association with the impacted tooth. We report a rare case of AOT associated with an impacted right mandibular lateral incisor in an 11-year-old female patient. PMID:26734563
Kato, Y; Tomizawa, K; Kato, T
Gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH), are synthesized specifically in the gonadotropes of the anterior pituitary. The aim of this study was to investigate nuclear factors that bind specifically to the porcine FSH beta-subunit gene. We examined nuclear protein binding to 2.75 kilobase pairs (kbp) of DNA adjacent to the porcine FSH beta-subunit gene: about 2.32 kbp of upstream DNA and 0.43 kbp of downstream DNA. The upstream region contains only TATA box, CACCC element, and some imperfect sequences of cAMP-responsive element, activator protein-1 binding site, and activator protein-2 binding site. Gel mobility shift assay using nuclear proteins extracted from the porcine anterior pituitary revealed that the proteins bound to a limited region of DNA, 107 bp long (designated as Fd2), located about -800 bp upstream from the transcription initiation site. Competitive binding assays demonstrated that the protein binding was sequence specific; the addition of excess amounts of several putative regulatory sequences and plasmid (non-homologous) DNA fragments did not reduce the binding. Furthermore, all five subfragments of Fd2 were also bound by the pituitary nuclear proteins, showing that the entire region of Fd2 is involved in this interaction. Southwestern blotting demonstrated that at least seven protein species of 110, 98, 78, 63, 52, 42, and 35 kDa recognize Fd2. Nuclear proteins from several other porcine tissues were also able to bind to the Fd2 fragment but the gel shift patterns were different and the bindings were weak, although only the cerebellum showed a pattern of binding that was similar to that of the anterior pituitary. These data suggest that multiple proteins of the anterior pituitary recognize a specific region of the porcine FSH beta-subunit gene.
Croce, A; Moretti, A; Vitullo, F; Castriotta, A; Rosa, De M; Citraro, L
Mandibular condylar neck fractures and subcondylar fractures represent, respectively, 19-29% and 62-70% of all mandibular fractures; treatment involves some problems, common to both, concerning the choice of an adequate approach. Herewith, personal experience is reported related to the surgical treatment of some cases of mandibular condylar neck and subcondylar fractures by transparotid approaches with partial parotidectomy, removing the salivary tissue overlying the condylar neck and/or the subcondylar region. Over the last 5 years, we observed 22 fractures of the condylar neck and 10 fractures of the subcondylar region. In 13 patients (11 male, 2 female, age range 10-68 years, mean 33 years), 10 of whom had other mandibular and/or other maxillo-facial and skeleton fractures - 50% of these with dislocated condylar heads - and the other 3 for their free choice, regarding the different treatments, 18 transparotid approaches with partial parotidectomy (bilateral in 5 cases), were performed reducing and fixing 12 condylar neck fractures and 5 subcondylar region fractures with appropriate plates (2.0 mm) and screws. After surgery, no intermaxillary fixation was performed. Complications included 4 salivary fistulae (bilateral in 1 patient), which closed spontaneously after 4 or 5 weeks with a dressing, 1 case of Frey's syndrome, which healed after 2 treatments with botulin and 6 cases of transient facial palsy lasting 4-8 weeks (1 case bilateral) affecting zygomatic, buccal and marginal mandibular nerves. During follow-up, functional parameters considered were: restoration of original pre-injury occlusion; vertical, lateral and protrusion mandibular movements. All patients re-acquired the original pre-injury occlusion; the maximal post-operative intrinsical distance was at least 40 mm after a variable period of rehabilitation and lateral and protrusion movements also led to satisfactory final results. All patients were free of pain and had no deflection or clicking upon
Wang, Hom-Lay; Sabalys, Gintautas
ABSTRACT Objectives The purpose of the present study was to review the literature of how to identify the mental foramen, mandibular incisive canal and associated neurovascular bundles during implant surgery and how to detect and avoid the damage of these vital structures during implant therapy. Material and Methods Literature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were mandibular incisive canal, mental foramen, mental nerve, anterior mental loop. The search was restricted to English language articles, published from 1979 to November 2009. Additionally, a manual search in the major anatomy, dental implant, and periodontal journals and books was performed. Results In total, 47 literature sources were obtained and reviewed. The morphology and variations of the mandibular incisive canal, mental foramen and associated neurovascular bundles were presented as two entities. It suggested that clinicians should carefully assess these vital structures to avoid nerve/artery damage. Conclusions The mandibular incisive canal, mental foramen and associated neurovascular bundles exist in different locations and possess many variations. Individual, gender, age, race, assessing technique used and degree of edentulous alveolar bone atrophy largely influence these variations. It suggests that the clinicians should carefully identify these anatomical landmarks, by analyzing all influencing factors, prior to their implant surgical operation. PMID:24421959
Costa, Elisângela Maria Cunha; Lucas, Bárbara Lima; Silva, Mariana Reis; Vilarinho, Renata Hinhug; de Faria, Paulo Rogério; Loyola, Adriano Mota
Periosteal (juxtacortical) chondrosarcoma (PC) is a well-differentiated malignant cartilage-forming tumor arising from the external bone surface, especially in long bones. The therapy of choice is en-bloc resection and, in general, its prognosis is good. This paper reports a rare case of PC affecting the mandible of a 41-year-old man. The lesion presented as a slow-growing-painless swelling that lasted 2 months. Computed tomography scan showed a tumoral mass arising from the external bone surface, extending into the adjacent soft tissue presenting patchy regions of popcorn-like calcifications. A final diagnosis of PC (grade II) was rendered after biopsy. Hemimandibulectomy was undertaken followed by complementary radiotherapy with 70 Gy. Although no episodes of recurrence or metastasis had been noticed after 18 months of follow-up, the patient died and causa mortis could not be established.
Berrone, M; Aldiano, C; Pentenero, M; Berrone, S
This study describes an unusual case of mandibular asymmetry after fibula free flap reconstruction in a young man following major facial trauma that was corrected using a custom-made polyetheretherketone prosthesis. There is little information in the literature on the use of alloplasts to correct mandibular asymmetry as interest in 'aesthetic re-modelling' has traditionally focused on nasal, zygomatic and chin regions. This report demonstrates that this technique can be used successfully to address selected cases of mandibular asymmetry.
Smidt, Ami; Sharon, Eldad; Adler, Mordekhai Lipovetsky
The loss of an entire tooth in the anterior region is accompanied by impairment of esthetics, function, phonetics, and self-esteem. It is common knowledge that treatment with implants during childhood or early adolescence is not an option. Splinting of adjacent teeth during growth and development may interfere with the independent process of teeth realignment and repositioning during that phase of life. Other creative solutions must be offered, such as free-standing composite buildup restorations on compromised broken teeth or single wing/cantilevered restorations adhered to one neighboring tooth during the growth period. The positive effects of reinforced composite materials were researched and presented in the literature. Their use is clearly indicated for interim and economical restorations. Long-term follow-up on a mandibular incisor that experienced trauma, losing its clinical crown and vitality when the patient was 12 years of age, is discussed with all the various aspects of material selection, future considerations, and long-term follow-up to adulthood, when a conventional crown was prepared and delivered.
Iwanaga, Joe; Kamura, Yasuhiko; Tanaka, Tsuyoshi; Watanabe, Koichi; Kusukawa, Jingo; Oskouian, Rod J; Tubbs, R Shane
Our previous studies based on intraoral dissection of fresh cadavers demonstrated the fissure and loose connective tissues behind the mucosa between the incisivus labii inferioris (ILI) and buccinator (BM) muscles. However, this raised new questions about the relationship among these muscles, the fissure and the buccal space. To our knowledge, no pathway to the oral cavity from the buccal space has been previously demonstrated, although such a pathway would better explain some routes of infection. Therefore, the aim of this study was to clarify the relationship among the mimetic muscles attached to the mandible, the fissure, and the buccal space. Twenty sides from 10 fresh frozen adult cadaveric Caucasian heads were used. The relationships among the ILI, BM, mandible, and buccal space were investigated with dissection and fluoroscopy. In all specimens, the fissure between the lateral border of the ILI and the anterior border of the BM formed the entrance of a space (here termed the bucco-mandibular space), which corresponded to the buccal mucosa in the premolar region. The superior border of this space was formed by the platysma and associated fascia, which was continuous with the masseteric fascia. This fascia clearly separated this space from the buccal space, which was located lateral to the BM and superior to this space. Clin. Anat. 30:958-962, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Ikeda, Michiyo; Miyamoto, Jun J; Takada, Jun-Ichi; Moriyama, Keiji
The purpose of this study was to evaluate the hypothesis that 3-dimensional mandibular morphology is correlated with condylar movement in patients with mandibular asymmetry. Subjects were classified into 2 groups (n = 25 each): mandibular asymmetry with a menton deviation greater than 4 mm and no mandibular asymmetry with a menton deviation less than 4 mm. Linear and volumetric measurements of 3-dimensional mandibular morphology were recorded using computed tomography. Mandibular functional movement was recorded by computerized axiography (CADIAX; Gamma Dental, Klosterneuburg, Austria), and condylar path length, sagittal condylar inclination, and transverse condylar inclination on protrusion were measured. We calculated side-to-side asymmetry (shifted side vs nonshifted side) in mandibular morphology and assessed condylar movement by using an asymmetry ratio (nonshifted side/shifted side). Significant differences in mandibular morphology and condylar movement were found between the 2 groups. In the group with menton deviation greater than 4 mm, significant correlations were found between the asymmetry ratio of mandibular morphology and condylar movement: ie, condylar path length and transverse condylar inclination. No significant correlations were found between any of these measurements in the group with menton deviation less than 4 mm. In support of our hypothesis, the results suggested that 3-dimensional mandibular morphologic asymmetry is associated with condylar movement in subjects with mandibular asymmetry. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Mikami, Hiroko; Nakatsuka, Michiko; Iwai, Yasutomo
We conducted a Fourier analysis on data obtained using correlation and principal component analyses of parallel-standardized dental study models; both maxillary and mandibular dental arches were predominantly round square in shape. The present study compared and determined the contribution ratio and reproducible coefficients of amplitudes (factors affecting dental arch forms), and demonstrated that the 1st to 4th and the 1st to 6th Fourier harmonics reproduced maxillary and mandibular dental arch forms, respectively. The correlation analyses of the constant term and amplitudes demonstrated that significant differences in the 2nd harmonic amplitude was strongly correlated with the curvature of anterior teeth and the length-to-width ratio in maxillary dentitions. By comparison of the constant term and amplitudes between different arch types, we did not observe significant differences in the constant term and the 1st amplitude of maxillary dentitions and in constant term and all amplitudes of mandibular dentitions. Nevertheless, the study revealed high contribution ratios of the 1st (in mandibular dentitions) and the 2nd (in maxillary dentitions) amplitudes essentially affecting the reproducibility of arch forms. The 1st amplitudes demonstrated a bow-like arrangement of all arch types, while the 2nd amplitudes adjusted the anterior-teeth curvature and in particular demonstrated the length-to-width ratio of maxillary dentitions. The 3rd and the 4th amplitudes were also determinants of the anterior-teeth curvature of maxillary dentitions. The 6th amplitude was necessary for reproduction, but showed no difference between varying mandibular dental arch types. Collectively, we conclude that the establishment of a Fourier series significantly reproduced maxillary but not mandibular dental arch forms.
Payne, A G; Solomons, Y F
This article presents a critical review of the literature on the prosthodontic maintenance requirements of mandibular mucosa- and implant-supported overdentures. A search of the literature produced 35 papers pertaining to prospective and retrospective studies. The relationship of these prosthodontic maintenance requirements to the axis of rotation treatment concept was examined. More often than not, 2 anterior mandibular implants either splinted (round or ovoid bars) or unsplinted (balls or magnets) have been used to evaluate this prosthodontic follow-up. Wide variation existed in the categories used for prosthodontic complications. Although principally related to alterations of overdenture contour and aspects of patrix and matrix maintenance, they also provide subjective information on relines and the rationale for avoiding overdenture fractures. These prosthodontic maintenance requirements undoubtedly have a direct impact on the time to retreatment of mandibular mucosa- and implant-supported overdentures. There appears to be a need for a more uniform, standardized categorization with criteria for determining prosthodontic success, in terms of maintenance requirements and complications, for mandibular mucosa- and implant-supported overdentures. Controlled prospective evaluations of exact prosthodontic maintenance requirements of mandibular overdentures using different systems are lacking and encouraged. There is also an absence of prospective studies on such maintenance requirements of mandibular overdentures using multiple round bars on 3 or 4 implants.
Rowe, N M; Mehrara, B J; Luchs, J S; Dudziak, M E; Steinbrech, D S; Illei, P B; Fernandez, G J; Gittes, G K; Longaker, M T
Recruitment of a blood supply is critical for successful bone induction and fracture healing. Despite the clinical success of distraction osteogenesis (DO), an analysis of angiogenesis during membranous bone DO has not been performed. The purpose of this study was to evaluate the temporal and spatial pattern of angiogenesis during mandibular DO. The right hemimandible of adult male rats was osteotomized, and a customized distraction device was applied. Following a 3-day latency period, distraction was begun at a rate of 0.25 mm twice daily for 6 days (3.0 mm total; 12% increase in mandibular length). Three animals each were sacrificed on days 2, 4, and 6 of distraction (D1, D2, and D3 respectively), or after 1, 2, or 4 weeks of consolidation (C1, C2, and C3 respectively). Two experienced pathologists reviewed the regenerate histology, and angiogenesis was assessed by counting the number of blood vessels per intermediate-power field (IPF). Statistical analysis was performed using analysis of variance, with p < or = 0.05 considered significant. Results demonstrate that mandibular DO was associated with an intense vascular response during the early stages of distraction (D1). On average, 31.5+/-7.9 vessels were noted in each IPF examined during this time point. The number of blood vessels in the distraction regenerate decreased significantly during the later distraction time points, with approximately 14.0+/-2.0 and 14.7+/-3.5 blood vessels per IPF in sections obtained after days 4 and 6 of distraction (D2, D3) respectively. However, blood vessels at these time points took on a more mature histological pattern. During the consolidation period, the number of blood vessels noted in the regenerate decreased with 8.0+/-2.6, 9.3+/-2.1, and 4.0+/-2.0 vessels per IPF in sections obtained after 1, 2, or 4 weeks of consolidation (C1, C2, C3) respectively (p < 0.05 compared with vessel counts during the earliest distraction time point). This study demonstrates for the first
González-Otero, Sergio; Navarro-Cuéllar, Carlos; Escrig-de Teigeiro, Margarita; Fernández-Alba-Luengo, Javier; Navarro-Vila, Carlos
Osteochondroma is one of the most common benign bone tumours, although not in the craniofacial region. More than half of these appear in the coronoid process. It can appear on the mandibular condyle, especially in its medial half, and mainly affects women aged around forty years. We present the case of a 51-year-old woman with pain of several months' duration in the right temporomandibular joint (TMJ) and no other symptoms. Panoramic radiography showed an enlarged condyle with no subchondral cysts. Computed tomography showed a bony proliferation with benign signs and a scintigraphy revealed an increased uptake in the condyle. Due to the painful clinical symptoms, a surgical procedure using preauricular and retromandibular approaches was performed to excise the condyle. The resulting defect, which was 9 mm high, was reconstructed by means of a vertical sliding osteotomy of the mandibular ramus and two miniplates for osteosynthesis. Almost two years later, the patient is symptom-free and has a normal opening with no malocclusion or deviation in the opening pattern. We present and discuss different reconstruction options after condylectomy.
Kumar, K. Pavan; Nujella, Surya Kumari; Gopal, S. Sujatha
For patients who require removal of anterior teeth and their replacement various treatment modalities are available. With advancement in technology and availability of glass/polyethylene fibres, use of natural tooth as pontic with fibre reinforced composite restorations offers the promising results. The present case report describes management of periodontally compromised mandibular anterior tooth using natural tooth pontic with fibre reinforcement. A 1-year follow-up showed that the bridge was intact with good esthetics and no problem was reported. PMID:27195156
Segura-Egea, Juan J; Jiménez-Rubio, Alicia; Ríos-Santos, José V; Velasco-Ortega, Eugenio
The talon cusp, or dens evaginatus of anterior teeth, is a relatively rare dental developmental anomaly characterized by the presence of an accessory cusplike structure projecting from the cingulum area or cementoenamel junction. This occurs in either maxillary or mandibular anterior teeth in both the primary and permanent dentition. This article reports five cases of talon cusp, two of them bilateral, affecting permanent maxillary central and lateral incisors and canines that caused clinical problems related to caries or occlusal interferences.
Prabhu, RV; Chatra, L; Shenai, P; Kishore, S; Nithin, S; Savitha, D; Prabhu, V
Talon cusp (TC) is a relatively uncommon developmental anomaly characterized by cusp-like projections from the cemento-enamel junction to a variable distance toward the incisal edge of an anterior tooth. It usually presents on palatal/lingual surface of the anterior teeth. Studies have revealed that it consists of enamel, dentine and a variable amount of pulp tissue. Presence of this cusp on the facial surface of an anterior tooth is a rare finding with very few cases being reported in the literature. The effects of TCs are mainly aesthetic and functional. The management requires a sufficient knowledge of the present clinical entity and the problems associated with it. Early detection and treatment plays a very vital role in avoiding the future complications. The present case reports a 25-year-old male patient with a facial TC on the mandibular left central incisor in which a prophylactic enameloplasty was carried out to avoid the stagnation of debris and stain. PMID:25031904
Yadav, Suresh; Tyagi, Shallu; Puri, Naveen; Kumar, Prince; Kumar, Puneet
To assess the relationship between impacted mandibular third molar presence and the risk for mandibular angle fracture with the effect of various positions of mandibular third molar and the risk of mandibular angle fracture. In the North Indian territory, a total of 289 patients with mandibular angle fractures were studied and evaluated for the possible relationship with impacted third molar on the basis of clinical and panoramic radiographical findings. Results that confirmed the highest risk for mandibular angle fracture was associated with mesioangular angulations (45.42%) followed by vertical (26.34%), distoangular in sequence and least risk was found with bucco-version angulations (2.67%) according to Winter's classification. Additionally, the highest risk of mandibular angle fracture was reported with partially erupted third molar (47.75%), followed by erupted (23.53%) and unerupted third molar (19.38%). The risk for mandibular angle fracture is not only affected by status of eruption, angulations, position, number of roots present in third molar but also by the distance of mandibular third molar from inferior border of mandible and the percentage of remaining amount of bone at the mandibular angle region.
Susarla, Srinivas M; Evans, Kelly N; Kapadia, Hitesh; Vasilakou, Nefeli; Egbert, Mark A; Hopper, Richard A
To evaluate changes in mandibular morphology in infants with Robin sequence (RS) after mandibular distraction osteogenesis (MDO) and compare the post-distraction morphology with that in infants without RS and infants with RS who had not undergone MDO. Infants with RS treated with MDO were retrospectively evaluated over a 12-year period. All patients had pre-distraction and end-consolidation maxillofacial computed tomograms. Morphologic features of the mandible were divided into ramus and condyle, body and symphysis, and composite measurements. Post-distraction RS mandibular morphology was compared with pre-distraction morphology, as well as to age-matched infants without RS and age-matched infants with RS who had not undergone MDO. Comparisons were done using nonparametric paired-samples analyses. During the study period, 17 patients with RS treated with MDO met the inclusion criteria for the study. The mean ages at distraction and end-consolidation were 1.95 ± 3.24 and 8.46 ± 5.99 months, respectively. The post-MDO mandible was significantly different from the pre-MDO mandible with regard to the ramps-condyle unit and body-symphysis measurements, including development of a more parabolic mandibular arch form (P ≤ .001). Compared with age-matched non-RS infant mandibles, the post-distraction RS mandibles had similar morphologies. Compared with age-matched non-MDO RS mandibles, the post-distraction mandibles had significantly different morphologies anterior to the gonial angle, including a more parabolic arch form (P ≤ .006). MDO normalized mandibular morphology in infants with RS, with the greatest effect on measurements anterior to the gonial angle. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Objectives The purpose of this study was to estimate the volumetric change of augmented autobone harvested from mandibular body cortical bone, using cone-beam computed tomography (CBCT) and three-dimensional reconstruction. In addition, the clinical success of dental implants placed 4 to 6 months after bone grafting was also evaluated. Materials and Methods Ninety-five patients (48 men and 47 women) aged 19 to 72 years were included in this study. A total of 128 graft sites were evaluated. The graft sites were divided into three parts: anterior and both posterior regions of one jaw. All patients included in the study were scheduled for an onlay graft and implantation using a two-stage procedure. The dental implants were inserted 4 to 6 months after the bone graft. Volumetric stability was evaluated by serial CBCT images. Results No major complications were observed for the donor sites. A total of 128 block bones were used to augment severely resorbed alveolar bone. Only 1 of the 128 bone grafts was resorbed by more than half, and that was due to infection. In total, the average amount of residual grafted bone after resorption at the recipient sites was 74.6%±8.4%. Conclusion Volumetric stability of mandibular body autogenous block grafts is predictable. The procedure is satisfactory for patients who want dental implants regardless of atrophic alveolar bone. PMID:26568924
Berbel, Pablo; Ostrosky, Alejandro; Tosti, Franco
Dermoid cysts are unusual neoplasms and can occur in every part of the human body. They represent only 6.9% of all dermoid cysts in the head and neck region; in the oral cavity, the incidence is low, approximately 1.6% of all dermoid cysts. Our aim is to present an unusual case of a large sublingual dermoid cyst with mandibular prognathism caused by cyst growth. We reported a case of a large sublingual dermoid cyst in an 8-year-old female patient. A bibliographic research from 1937 to 2013 is reviewed and we found only three cases of mandibular deformity, of which only one was a dermoid cyst of the floor of the mouth. Removal of dermoid cysts of the floor of the mouth should be completed as early as detected, especially in newborns and infants when osseous growth abnormalities could result if removal is delayed.
Bural, Canan; Buzbas, Begum; Ozatik, Sebnem; Bayraktar, Gulsen; Emes, Yusuf
This case report describes the fabrication of a distal extension removable partial denture (RPD) of a 65-year-old man with implant support. Loss of fibroelasticity of the peripheral tissues and reduced mandibular vestibular sulcular depth due to a previous surgical resection and radiotherapy at the right side were the main clinical factors that created difficulty for denture retention and stability. The fabrication of a mandibular RPD supported by anterior teeth and two bilaterally placed implants in the molar area to convert from Kennedy Class 1 design to Kennedy Class 3 implant-bounded RPD is reported. Retention and stability of the denture were improved with implant support on the distal extension site of the RPD. The common clinical problems about distally extended RPDs are lack of retention and stability due to the movement around the rotational axis. Dental implant placement to the distal edentulous site minimizes the potential dislodgement of the RPD is popular. Implant-supported RPD can be suggested as an advantageous and cost-effective treatment option for the partially edentulous patients. PMID:28042277
Al-Khateeb, Susan N; Al Maaitah, Emad F; Abu Alhaija, Elham S; Badran, Serene A
To assess the morphology and dimensions of mandibular symphysis (MS) in different anteroposterior jaw relationships and to investigate whether craniofacial parameters have any correlation with its shape and/or dimensions. Lateral cephalograms of subjects with Class I, Class II, and Class III skeletal relationships were traced. Several craniofacial and MS parameters were measured. MS parameters were compared between the three groups using analysis of variance and were correlated with the craniofacial parameters using the Pearson correlation coefficient. Larger angle of concavity of the chin, more inclination of the alveolar bone toward the mandibular plane, and larger MS dimensions and area (P < .001) were found with a Class III skeletal relationship compared to Class I and Class II relationships. The Pearson correlation coefficient between Id-Me and AFH was r = 0.83 and between Id-Me and LAFH it was r = 0.81. The dimensions and configuration of MS in the Class III relationship were different than those in Class I and Class II relationships; the alveolar part of MS compensated for the skeletal relationship in the Class III pattern. MS dimensions were strongly correlated to anterior facial dimensions.
Jasinoski, Sandra C; Chinsamy, Anusuya
An investigation of bone microstructure of nonmammalian therapsids has revealed distinctive signals pertaining to their ontogenetic growth and biology. Until now, histological studies of the nonmammaliaform cynodonts have focused only on postcranial material. Through the examination of micro-computed tomography (micro-CT) scans and serial thin sections, the current study provides a novel perspective on the structure and growth of the mandible of Tritylodon, a derived herbivorous cynodont from southern Africa. By tracking histological features across the serial thin sections, trends in relocation and modelling are documented for the growing Tritylodon mandible. For example, during growth, localized changes in the cross-sectional shape of the mandible occurred. Localized deposits of new lamellar and fibrolamellar bone on the lateral edge indicate widening of the mandible during different episodes of growth. The presence of radial channels indicates the deepening of the mandible at its anterior and posterior ends. The relocation of the paired mental foramina suggests that the mandibular body lengthened mainly in the posterior direction. The medial movement of a posterior postcanine tooth during growth and eruption is recorded in the histology. This histological assessment also documents the presence of Sharpey’s fibres in the cellular cementum of the first incisor, providing novel and unequivocal evidence that it was attached to the Tritylodon jaw by a periodontal ligament. This is the first comprehensive study that uses histological analysis to document the growth dynamics of the mandible of a nonmammalian therapsid, thus providing a unique perspective of localized mandibular growth in a fossil animal.
Osborn, W S; Nanda, R S; Currier, G F
The effects of lip bumper treatment on the mandibular arch were observed in 32 patients with late transitional and early permanent dentitions. Dental cast measurements were made for arch perimeter, arch length, and arch width. Cephalometric radiographs were used to determine labial tipping of the incisors and distal movement of the molars. Arch circumference increased in all patients, ranging from 0.7 mm to 8.8 mm, with an average of 4.1 mm. The mean increase in arch length was 1.2 mm and was largely attributed to anterior tipping of the mandibular incisors. Change in arch length was the most predictive variable for the increase in arch circumference. Passive changes in arch width were recorded, with a mean increase of 2.0 mm in the intercanine distance and 2.5 mm in the first premolar distance. Arch width increments contributed to the increase in arch circumference, but the increases in arch width were not found to be predictive of the change in arch circumference. Changes in either arch circumference or arch length were not related to the duration of treatment, age and sex of the patient, or the eruption status of the permanent second molars.
Perri de Carvalho, Paulo Sergio; Janjacomo, Luiz Antonio; Ponzoni, Daniela
This clinical report describes the deepening of a patient's anterior mandibular lingual sulcus in combination with frenectomy and the use of an acrylic resin guiding device fixed to an osseointegrated dental implant to maintain the patency of the new sulcular depth.
Gallego, Lorena; Junquera, Luis; Villarreal, Pedro; de Vicente, Juan Carlos
Fracture of the mandibular genial tubercles is an uncommon pathology affecting edentulous patients with severe maxillary atrophy. Usually occurs spontaneously which complicates the diagnosis. Their importance lies in the functional alterations, which occur as a consequence of the disinsertion of the genihyoid and genioglossus muscles. The treatment of fracture of the genial tubercles is controversial, including no surgical intervention, excision of the avulsed bone fragments, and muscular repositioning. There have been only 11 cases reported in the literature of this fracture, most of them spontaneous. We present a difficult diagnosis situation of spontaneous fracture of the genial tubercles in an 86-year-old edentulous female with a painful sublingual and submental hematoma and anterior cervical echimosis. Computerized Tomography should be made to confirm the diagnosis. Surgical treatment was not necessary, and follow-up at 6 months revealed complete symptomatic recovery, and full return of function.
Pearlman, N.W.; Albin, R.E.; O'Donnell, R.S.
Myosseous-cutaneous flaps were used for mandibular reconstruction in 16 irradiated patients. Three of six sternomastoid-clavicle flaps failed (all in conjunction with a neck dissection), as did one of 10 pectoralis major-anterior-fifth rib flaps. One trapezius-scapular flap was used and it succeeded. We found the blood supply of the sternomastoid-clavicle flap too tenuous for use in conjunction with a neck dissection. The trapezius-scapular flap had too short an arc of rotation to be used for defects other than those in the horizontal ramus. In addition, this flap required a change of position and created an undesirable functional deformity. The pectoralis major-fifth rib flap, in contrast, could be used for a variety of defects, in conjunction with a neck dissection, and did not require a change of position during operation. We found it to be the most versatile and dependable of the flaps employed in this series.
Pfeiffer, Keram; Kinoshita, Michiyo
Visually guided behaviors require the brain to extract features of the visual world and to integrate them in a context-specific manner. Hymenopteran insects have been prime models for ethological research into visual behaviors for decades but knowledge about the underlying central processing is very limited. This is particularly the case for sky-compass navigation. To learn more about central processing of visual information in general and specifically to reveal a possible polarization vision pathway in the bee brain, we used tracer injections to investigate the pathways through the anterior optic tubercle, a prominent output target of the insect optic lobe, in the bumblebee Bombus ignitus. The anterior optic tubercle of the bumblebee is a small neuropil of 200 μm width and is located dorsolateral to the antennal lobe at the anterior surface of the brain. It is divided into a larger upper and a smaller lower subunit, both of which receive input from the optic lobe and connect to the lateral accessory lobe, and the contralateral tubercle, via two parallel pathways. The lower subunit receives input from the dorsal rim area (DRA) of the compound eye. The bumblebee DRA shares structural similarities with polarization-sensitive DRAs of other insects and looks similar to that of honeybees. We identified several neurons within this pathway that could be homologous to identified polarization-sensitive neurons in the locust brain. We therefore conclude that the pathway through the lower subunit of the anterior optic tubercle could carry polarization information from the periphery to the central brain.
Shamloo, Nafiseh; Safi, Yaser; Fathpour, Kamyar; Yaghmaei, Masood; Bahemmat, Nika
Mandibular canal is the most important anatomical landmark in the body of mandible which always must be considered for implant surgery in posterior mandibular region. Damage to vessels and inferior alveolar nerve that passes through the mandibular canal can cause problems such as hemorrhage and neurosensory disturbances. Damage to the mandibular canal can occur during implant surgery. Depending on the severity of injuries, it would result in temporary or permanent neurosensory disturbances. We have reported a case that mandibular canal narrowing occurred following implant surgery and resulted in anesthetic and hypoesthetic areas in the lower lip. Patient had a history of implant surgery in the region of teeth numbered 30 and numbered 31. The inserted implant failed after 6 years, and reimplantation was done in this area, but due to lower lip numbness in the right side, the second implant was removed, and another implant was inserted in the region of the tooth numbered 32. After 2 years, right lower lip numbness was reported again by the patient. Cone beam computed tomography images showed canal narrowing in the region of the tooth numbered 31 where the second implant was inserted. It seems that the main cause for anesthesia and hypoesthesia in this patient is canal narrowing due to damage during implant replacement and removal.
Shamloo, Nafiseh; Safi, Yaser; Fathpour, Kamyar; Yaghmaei, Masood; Bahemmat, Nika
Mandibular canal is the most important anatomical landmark in the body of mandible which always must be considered for implant surgery in posterior mandibular region. Damage to vessels and inferior alveolar nerve that passes through the mandibular canal can cause problems such as hemorrhage and neurosensory disturbances. Damage to the mandibular canal can occur during implant surgery. Depending on the severity of injuries, it would result in temporary or permanent neurosensory disturbances. We have reported a case that mandibular canal narrowing occurred following implant surgery and resulted in anesthetic and hypoesthetic areas in the lower lip. Patient had a history of implant surgery in the region of teeth numbered 30 and numbered 31. The inserted implant failed after 6 years, and reimplantation was done in this area, but due to lower lip numbness in the right side, the second implant was removed, and another implant was inserted in the region of the tooth numbered 32. After 2 years, right lower lip numbness was reported again by the patient. Cone beam computed tomography images showed canal narrowing in the region of the tooth numbered 31 where the second implant was inserted. It seems that the main cause for anesthesia and hypoesthesia in this patient is canal narrowing due to damage during implant replacement and removal. PMID:26288630
Ying, Binbin; Wu, Sufan; Yan, Sheng; Hu, Jing
In Asia, a round face rather is more acceptable than a square face. Intraoral mandibular angle ostectomy is a common aesthetic procedure for correcting a prominent mandibular angle. However, an operation of sheer straight-lined prominent mandibular angle resection would sometimes create extramandibular angles or palpable bone steps in the margin of mandibular body and produce unnatural lower one-third facial appearance, especially for a square and disproportional mandibular angle even extending to the middle mandibular body. This article describes the method of multistage mandibular angle ostectomy to produce a natural lower one-third facial contour. This method mainly focused on the posterior area of mandibular ostectomy by intraoral approach, although it has modifications. Mandibular contouring is realized first through bone cutting from antegonial notch posteriorly upperward, reaching to the middle ramus of the mandible near the earlobe; second ostectomy followed along mandible lower part is to get rid of extramandibular angle according to the preoperative design; sometimes necessarily, third ostectomy creates a smooth mandibular contour. From January 2000 to January 2010, 379 patients were operated on, and satisfactory results were achieved. Thus, this procedure could avoid excessive bone cutting, extramandibular angles, unnatural appearance, and palpable bone steps.
Calgaro, A; Bison, L; Bellis, G B; Pozzi Mucelli, R
To stress the importance of CT depiction of the mandibular incisive canal. This anatomical structure contains a major neurovascular bundle and is thus very important in the planning of mandibular implants in the canine-incisive area. January through December 1998, sixty patients unselected by age and gender were submitted to mandibular CT. Axial slices were acquired with 1-1.5 mm thickness and 1 mm table feed, and the images were then reformatted with a dedicated dental software. Both the conventional and the Helical techniques were used. The incisive canal appears on Dentascan transverse reconstructions as a round low-density area within mandibular trabecular bone, which is surrounded by a higher-density rim representing the canal walls. This anatomical structure originates from the mental foramen and continues mesially to the mental symphysis. The mandibular canal was visualized in 95% of cases bilaterally (57/60); the incisive canal was depicted on the left side in 41.6% of cases (25/60) and on the right side in 51.6% (31/60). The importance of careful assessment of the mandibular canal course before implantology is now widely recognized. The same holds true for the canine-incisive region in the jaw, to detect the incisive canal if present and prevent any complications from its accidental damage. CT with a dedicated software showed the incisive canal in a large number of patients, which calls for precise reporting of its presence, course, and relationships with teeth.
Lee, Jae-Gi; Kim, Il-Soo; Kim, Young-Woo; Park, Jong-Tae; Hu, Kyung-Seok; Kim, Hyung-Gon; Kim, Hee-Jin
When performing distraction osteogenesis, the osteotomy is normally applied to the cortical bone posterior to the mandibular second molar. We measured the topographic thickness of the cortical and trabecular bone of the mandibular ramus and at the mandibular canal (MC) to provide crucial anatomic data aimed at minimizing complications and elucidating the most appropriate site for placing the distractor. Forty sides of the mandibles were prepared from 20 Korean cadavers (10 men and 10 women with a mean age of 68 years). The specimens were scanned and reconstructed into three-dimensional images using a micro-computed tomography system. Coronal and horizontal sectional images of the mandibular ramus were taken at thickness intervals of 2 mm from the reconstructed three-dimensional images. Image analysis software was used to measure the thicknesses of the cortical and trabecular bone and to identify the locations of the MC within the body and the mandibular ramus on each section. The mean thicknesses of the buccal cortical plate, trabecular bone, and lingual cortical plate were 2.9 mm (men, 3.0 mm; women, 2.8 mm), 9.1 mm (men, 9.8 mm; women, 8.5 mm), and 2.2 mm (men, 2.3 mm; women, 2.1 mm), respectively. The distance from the buccal surface of the mandible to the MC increased from 5.3 to 10.0 mm (men, 5.3-10.0 mm; women, 5.3-9.1 mm) when moving progressively anterosuperior from the mandibular angle region. Morphometric analyses of the mandibular ramus can provide crucial data when performing mandibular osteotomy and locating an appropriate placement site for a distractor device during the distraction-osteogenesis procedure.
Cobo-Vázquez, Carlos; Monteserín-Matesanz, Marta; López-Quiles, Juan
Background To develop a systematic review by assessing and comparing the different complications that occurs in bone graft surgery using the mandibular body, ramus and symphysis as donor sites. Material and Methods In order to respond to the following question, a systematic review was developed: does the use of intraoral mandibular body and ramus as donor sites in bone graft surgery, produce fewer and less severe complications in comparison to the use of the mandibular symphysis in patients that present bone resorption that needs augmentation using autologous grafts? The review was carried out between January 1990 and 2015, during which only clinical essays with a minimum follow-up period of six months were included. Results The initial search yielded a total of 2912 articles, of which 6 were finally selected. In total, 259 graft surgeries were performed; 118 using the mandibular body and ramus as donor sites, and 141, the symphysis. The most frequent complications that arose when using the mandibular symphysis were temporary sensory alterations in the anterior teeth (33.87%), followed by sensory alterations of the skin and mucosa (18.57%). As for the mandibular body and ramus donor sites, the most frequent complications relate to temporary sensory alterations of the mucosa (8.19%) and to minor postoperative bleeding (6.55%). Conclusions The analyzed results show a higher prevalence and severity of complications when using mandibular symphysis bone grafts, producing more discomfort for the patient. Therefore, it would be advisable to perform further clinical essays due to the lack of studies found. Key words:Alveolar ridge augmentation, autogenous bone, mandibular bone grafts, chin, mandibular symphysis, mandibular ramus. PMID:26827063
Goodday, Reginald H B
Mandibular fracture, specifically in the symphysis and body regions combined, is the most common facial fracture requiring hospitalization in North America. The primary treatment objective is to restore form and function by achieving anatomic reduction and placing fixation that eliminates mobility of the bone fragments. Several treatment options and surgical techniques are available for performing closed or open reduction. Special considerations are necessary when treating pediatric patients and fractures of the edentulous mandible. Complications relating to the tooth and denture-bearing regions of the mandible include infection, nonunion, and neurosensory changes.
Xu, Jia-Jie; Teng, Li; Jin, Xiao-Lei; Lu, Jian-Jian; Zhang, Chao
The extraction of mandibular third molars is a common dental procedure. The complications include hemorrhage, pain, dental fracture, the displacement of teeth or fragments, iatrogenic damage or luxation of the second molar, neurologic injuries, soft tissue damage, subcutaneous emphysema, trismus, swelling, infection, and iatrogenic mandibular fracture. Fracture of the angle of the mandible associated with third molar removal is a rare but severe complication. This article describes a case of mandibular angle fracture associated with third molar extraction after mandibular angle osteotectomy, including a brief review of the literature. The removal of the mandibular angle and the outer cortex of the mandible, especially the external oblique ridge, may contribute to the bone fracture. We conclude that the extraction of the lower third molar must be before the removal of the mandibular angle, and a soft diet for at least 4 weeks postoperatively is essential to prevent late mandible fracture.
Clifford, T; Lamey, P J; Fartash, L
In this study the presence of mandibular tori was related to conditions associated with parafunctional activity. Parafunction in the form of tooth clenching or grinding has been associated with temporomandibular disorders (TMD) and recently migraine. Patients attending a facial pain clinic in Belfast were assessed for the presence of tori and results compared to age and gender matched controls. The findings were that mandibular tori were present significantly more commonly in both migraineurs and TMD patients. The results support an association with parafunction in the aetiology of mandibular tori and suggest that tori are a useful marker of past or present parafunction in some patients.
Rubens, B C; Stoelinga, P J; Weaver, T J; Blijdorp, P A
The non-surgical treatment of mandibular condylar fractures, may occasionally result in articular imbalance and temporomandibular joint dysfunction. This may be attributed to condylar head displacement and resorption, resulting in a shortened vertical ramus and lost posterior vertical facial height. Restoring the vertical ramus height is essential in the treatment of such dysfunction, and may be accomplished by unilateral, or bilateral ramus osteotomies. Four examples of patients treated with mandibular ramus osteotomies to restore vertical ramus height, with subsequent improvement in occlusal balance and function are presented. The use of the sagittal split mandibular osteotomy and the external vertical ramus osteotomy, stabilized with small osseous plates, and monocortical screws, is discussed.
Ai, Chong Jun; Jabar, Nazimi Abd; Lan, Tan Huann; Ramli, Roszalina
Enlargement of the mandibular canal is a rare radiological finding. Clinically, it may or may not be associated with sensory deficits. We report four cases of widening of the mandibular canal observed with various methods of imaging with different clinical characteristics. We describe this unique radiological finding and elaborate the importance of quality assessment of the imaging that is vital for accurate diagnosis and treatment planning. Clinicians should be mindful when assessing the imaging whenever the size of the mandibular canal is implicated. The case ranged from a benign tumor to malignancy, radiological errors, and artifacts. A more superior imaging or treatment modality was necessary to ascertain the diagnosis. PMID:28781925
Güler, A U; Sumer, M; Sumer, P; Biçer, I
The purpose of this study was to determine variations in the vertical height measurements in the edentulous maxilla and mandible, and to assess positions of the maxillary sinus, mandibular foramen, and the mandibular canal, which are important for implant length selection and planning using panoramic radiographs. The study sample included 346 edentulous alveolar ridges of 90 men and 83 women. Sixty-three dentate patients' panoramic radiographs were used for location of the first premolar and molar area. Panoramic radiographs were made with a Siemens Orthophos panoramic machine which had been standardized previously. All radiographs were made using a standardized manner by the same technician. Fourteen sites were measured on every panoramic radiograph whenever possible, eight sites in the maxilla and six sites in the mandible. Correlation analyses were performed between age groups and all measurements to determine if age is significant as a covariate. In order to examine the effect of gender the statistical analysis of differences between men and women was performed with Student t-test. The 5% significance level was used for statistical significancy. The height of the maxilla and the mandible in the anterior, first premolar, and first molar regions were significantly greater in men than in women. A majority of the most inferior border of the maxillary sinuses was located anterior to the first molar area (premolar regions) both in men (48.9%) and women (55.4%). Although, there was no statistically significant difference between edentulous men and women for the vertical distances from the mental foramen to the alveolar crest, and horizontal distances from mental foramen to midline, there were statistically significant differences between edentulous men and edentulous women for the vertical distances from the upper border of the mandibular canal to the alveolar crest in the first molar area. Mental foramens were located at the crest of the ridge in 7.2% of the
Andreishchev, A R; Nicot, R; Ferri, J
Mandibular angle resection is rarely used, but is a highly effective means of correcting facial defects. We report a mandibular angle resection technique associated with the removal of a part of hypertrophic masseter muscles and resection of buccal fat pad. Anatomical reminders: the most important entities are the facial artery and vein, crossing the lower margin of the jaw just in front of the anterior boarder of the masseter muscle and the temporomaxillary vein, passing through the temporomaxillary fossa; preoperative aspects: the preoperative examination included a radiological assessment of the shape and size of the mandibular angle; surgical technique: an intra-oral approach was usually used. The most effective and convenient method for the osteotomy was using a reciprocating saw. This technique allowed achieving a smooth contour of masseter muscles during masticatory movements or at rest. Eleven mandibular angle resections were performed from 2001 to 2009. The surgery was supplemented by remodeling the lower margin of the jaw for 5 other patients. No permanent facial palsy was noted. One patient presented a unilateral long-term loss of sensitivity of the lower lip and chin. This surgical technique if simple even requires using good technical equipment, and observing a set of rules. Using these principles allows simplifying the surgical technique, and decreasing its morbidity. A part of the masseter muscles and the buccal fat pad can sometimes be resected to improve the morphological results. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
de Souza Batista, Victor Eduardo; de Souza Batista, Fábio Roberto; Vechiato-Filho, Aljomar José; Lemos, Cleidiel Aparecido de Araújo; Pellizzer, Eduardo Piza; Verri, Fellippo Ramos
This article reports a case of oral rehabilitation with two-implant-retained mandibular overdenture using bar/clip and ball attachment bilaterally on the distal side. A patient aged 69 years, fully edentulous, presented herself to private practice complaining about the instability of mandibular denture. Several possibilities of rehabilitation with advantages and disadvantages were explained to the patient, based in the clinical and radiograph examinations, and patient desire, in which she opted by conventional maxillary complete denture and two-implant-retained mandibular overdenture. Two external hexagon implants of 3.75 × 10 mm were placed in anterior area of mandible. The fabrication of the metal framework with bar/clip and ball attachment bilaterally on the distal side was planned based on prior arrangement of the artificial teeth. Internal adaptation and occlusal adjustments were performed in the day of insertion of finalized denture and instructions about maintenance and sanitation. The patient showed satisfaction with the final result of her treatment, and no complications were observed during this period. The association of bar/clip with ball system may be viable as option of retention for mandibular implant-retained complete overdenture; however, further randomized controlled trials are necessary to obtain detailed knowledge about the topic.
Tözüm, Tolga F; Dursun, Erhan; Uysal, Serdar
The aim of the present study was to investigate whether the mandibular cortical index (MCI) has a relationship with fractal dimension of bone and/or implant stability, and to justify the possible association between MCI, fractal dimension, and stability. Eighty-two subjects who received dental implants to replace missing mandibular premolar/molar sites were selected. Three months after surgical placement, implants were restored with fixed ceramic fused metal crowns. MCI was evaluated at baseline; fractal dimensions were measured with fractal analysis (FA) and implant stability quotient (ISQ) with resonance frequency analysis immediately after surgery and 12-month follow-up. FA at mesial and distal regions for Class 1, Class 2, and Class 3 MCI resulted with significant increases at 12-month follow-up compared to baseline. The ISQ in patients with Class 2 and Class 3 MCI resulted with a significant decrease compared to Class 1 MCI at baseline and at 12 months. All MCI classes evaluated with ISQ and FA at baseline values resulted with significant increases at 12 months. Significant correlations were considered for all mandibular posterior implants between baseline and 12-month measurements for ISQ and FA evaluations. Fractal analysis may be a useful method for understanding the healing process around implants and implant stability quotient values. Mandibular cortical index evaluations should be considered before implant procedures, which may provide a presurgical treatment plan and may provide information about the mandibular bone quality.
Efstratiadis, Stella; Baumrind, Sheldon; Shofer, Frances; Jacobsson-Hunt, Ulla; Laster, Larry; Ghafari, Joseph
The aims of this study were (1) to evaluate cephalometric changes in subjects with Class II Division 1 malocclusion who were treated with headgear (HG) or Fränkel function regulator (FR) and (2) to compare findings from regional superpositions of cephalometric structures with those from conventional cephalometric measurements. Cephalographs were taken at baseline, after 1 year, and after 2 years of 65 children enrolled in a prospective randomized clinical trial. The spatial location of the landmarks derived from regional superpositions was evaluated in a coordinate system oriented on natural head position. The superpositions included the best anatomic fit of the anterior cranial base, maxillary base, and mandibular structures. Both the HG and the FR were effective in correcting the distoclusion, and they generated enhanced differential growth between the jaws. Differences between cranial and maxillary superpositions regarding mandibular displacement (Point B, pogonion, gnathion, menton) were noted: the HG had a more horizontal vector on maxillary superposition that was also greater (.0001 < P < .05) than the horizontal displacement observed with the FR. This discrepancy appeared to be related to (1) the clockwise (backward) rotation of the palatal and mandibular planes observed with the HG; the palatal plane's rotation, which was transferred through the occlusion to the mandibular plane, was factored out on maxillary superposition; and (2) the interaction between the inclination of the maxillary incisors and the forward movement of the mandible during growth. Findings from superpositions agreed with conventional angular and linear measurements regarding the basic conclusions for the primary effects of HG and FR. However, the results suggest that inferences of mandibular displacement are more reliable from maxillary than cranial superposition when evaluating occlusal changes during treatment.
Ansado, Jennyfer; Collins, Louis; Fonov, Vladimir; Garon, Mathieu; Alexandrov, Lubomir; Karama, Sherif; Evans, Alan; Beauchamp, Miriam H
Most of the studies conducted on the development of the corpus callosum (CC) have been limited to a relatively simple assessment of callosal area, providing an estimation of the size of the CC in two dimensions rather than its actual measurement. The goal of this study was to revisit callosal development in childhood and adolescence by using a three-dimensional (3D) magnetic resonance imaging template of the CC that considers the horizontal width of the CC and compares this with the two-dimensional (2D) callosal area. We mapped callosal growth in a large sample of youths followed longitudinally (N = 370 at T1; N = 304 at T2; and N = 246 at T3). Both techniques were based on a five-section subdivision of the CC. The results obtained with the 3D method revealed that the rate of CC growth over a 4-year period in the rostrum, the genu, the anterior body and the splenium was significantly higher in the youngest age group (< 7 years) than in older groups, indicating an intense period of development in early childhood for the anterior and posterior parts of the CC. Similar results were obtained when 2D callosal area was used for the anterior and posterior parts of the CC. However, divergent results were found in the mid-body and the caudal body of the CC. As shown by differences between 2D estimations and actual 3D measurements of callosal growth, our study highlights the importance of considering the horizontal width in measuring developmental changes in the CC. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Xiang, Guo-lin; Long, Xing; Deng, Mo-hong; Han, Qian-chao; Meng, Qing-gong; Li, Bo
We investigated the incidence of ankylosis of the temporomandibular joint (TMJ) after open operations for fractures of the mandibular condyle, and analysed possible risk factors in a total of 385 patients with 492 condylar fractures who had been operated on in our department from 2001 to 2010. Sixteen patients developed postoperative ankylosis of the TMJ with 26 joints (5%) affected during a follow-up of 6 months-10 years. Of the 492 condylar fractures, the most common ones that were associated with postoperative ankylosis were those of the condylar head (20/248), followed by the condylar neck (6/193). Subcondylar fractures did not cause postoperative ankylosis (0/51). Among the 16 patients with postoperative ankylosis, 13 had associated anterior mandibular fractures. Long-screw (bicortical screw) fixation of fractures of the condylar head seemed to be associated with a lower incidence of postoperative ankylosis than fixation by miniplate and wire or removal of the fractured fragment. The articular discs were damaged in all ankylosed joints, and the remaining fractured fragment was found in 10 ankylosed joints after fractures of the condylar head. The results suggest that fractures of the condylar head are more prone to lead to postoperative ankylosis of the TMJ, and that the possible risk factors seem to include the technique used for fixation and damage to the disc, together with an anterior mandibular fracture with the fractured fragment remaining.
Vervaat, F E; Bouwmeester, S; van Hellemond, I E G; Wagner, G S; Gorgels, A P M
The myocardial area at risk (MaR) is an important aspect in acute ST-elevation myocardial infarction (STEMI). It represents the myocardium at the onset of the STEMI that is ischemic and could become infarcted if no reperfusion occurs. The MaR, therefore, has clinical value because it gives an indication of the amount of myocardium that could potentially be salvaged by rapid reperfusion therapy. The most validated method for measuring the MaR is (99m)Tc-sestamibi SPECT, but this technique is not easily applied in the clinical setting. Another method that can be used for measuring the MaR is the standard ECG-based scoring system, Aldrich ST score, which is more easily applied. This ECG-based scoring system can be used to estimate the extent of acute ischemia for anterior or inferior left ventricular locations, by considering quantitative changes in the ST-segment. Deviations in the ST-segment baseline that occur following an acute coronary occlusion represent the ischemic changes in the transmurally ischemic myocardium. In most instances however, the ECG is not available at the very first moments of STEMI and as times passes the ischemic myocardium becomes necrotic with regression of the ST-segment deviation along with progressive changes of the QRS complex. Thus over the time course of the acute event, the Aldrich ST score would be expected to progressively underestimate the MaR, as was seen in studies with SPECT as gold standard; anterior STEMI (r=0.21, p=0.32) and inferior STEMI (r=0.17, p=0.36). Another standard ECG-based scoring system is the Selvester QRS score, which can be used to estimate the final infarct size by considering the quantitative changes in the QRS complex. Therefore, additional consideration of the Selvester QRS score in the acute phase could potentially provide the "component" of infarcted myocardium that is missing when the Aldrich ST score alone is used to determine the MaR in the acute phase, as was seen in studies with SPECT as gold
Children with mandibular growth deficiency may develop airway obstruction. The standard treatment of severe airway obstruction involves invasive procedures such as tracheostomy. Mandibular distraction osteogenesis has been proposed in neonates with mandibular deficiency as a treatment option to avoid tracheostomy procedure later in life. Both tracheostomy and distraction osteogenesis procedures suffer from substantial shortcomings including scarring, unpredictability, and surgical complications. Forward jaw positioning appliances have been also used to enhance mandible growth. However, the effectiveness of these appliances is limited and lacks predictability. Current and future approaches to enhance mandibular growth, both experimental and clinical trials, and their effectiveness are presented and discussed. PMID:23819121
Willis, Mary S; Schacht, Ryan N; Toothaker, Randy
Few U.S. adults today experience life without permanent anterior teeth and know little about how an incomplete anterior dentition affects adult well-being. Sudanese refugees, who had resettled in the U.S. and who had six mandibular anterior teeth ritually extracted during youth, provided an opportunity to examine the significance of the effect of this partial edentulism. The authors interviewed five adult refugees whose anterior dentition was restored using dental implants. Factors considered before and after restoration included incisal ability, food item recognition, food consumption patterns and related social factors. Before restoration of the anterior dentition, participants could not incise typical foods eaten in the U.S. and expressed embarrassment about their dental status, which limited smiling, speaking and social interaction. This case series offers insight into the bio-cultural importance of the anterior dentition for all populations living with a visible gap in the lower jaw.
Solem, R. Christian; Ruellas, Antonio; Miller, Arthur; Kelly, Katherine; Ricks-Oddie, Joni L.; Cevidanes, Lucia
Introduction Disordered craniofacial development frequently results in definitive facial asymmetries that can significantly impact a person's social and functional well-being. The mandible plays a prominent role in defining facial symmetry and, as an active region of growth, commonly acquires asymmetric features. Additionally, syndromic mandibular asymmetry characterizes craniofacial microsomia (CFM), the second most prevalent congenital craniofacial anomaly (1:3000 to 1:5000 live births) after cleft lip and palate. We hypothesized that asymmetric rates of mandibular growth occur in the context of syndromic and acquired facial asymmetries. Methods To test this hypothesis, a spherical harmonic-based shape correspondence algorithm was applied to quantify and characterize asymmetries in mandibular growth and remodeling in 3 groups during adolescence. Longitudinal time points were automatically registered, and regions of the condyle and posterior ramus were selected for growth quantification. The first group (n = 9) had a diagnosis of CFM, limited to Pruzansky-Kaban type I or IIA mandibular deformities. The second group (n = 10) consisted of subjects with asymmetric, nonsyndromic dentofacial asymmetry requiring surgical intervention. A control group (n = 10) of symmetric patients was selected for comparison. A linear mixed model was used for the statistical comparison of growth asymmetry between the groups. Results Initial mandibular shape and symmetry displayed distinct signatures in the 3 groups (P < 0.001), with the greatest asymmetries in the condyle and ramus. Similarly, mandibular growth had unique patterns in the groups. The dentofacial asymmetry group was characterized by significant asymmetry in condylar and posterior ramal remodeling with growth (P < 0.001). The CFM group was characterized by asymmetric growth of the posterior ramus (P < 0.001) but relatively symmetric growth of the condyles (P = 0.47). Conclusions Forms of CFM are characterized by active and
Steenkamp, Gerhard; Venter, Leon; Crossley, David; Buss, Peter
A 52-month-old Canadian beaver was presented for treatment of lip trauma resulting from overgrowth of the right mandibular incisor tooth following earlier loss of the right maxillary incisor tooth. Extraction of the affected tooth was considered, but rejected due to the length of the embedded portion of rodent mandibular incisor teeth. The lip injury was managed by crown reduction (odontoplasty) of the overgrowing incisor tooth pending a more permanent treatment plan. A 2-cm apicoectomy of the right mandibular incisor tooth was performed to arrest growth of the tooth when the beaver was 82-months-old. The remainder of the tooth continued to erupt and was completely expelled during a 9-month period with one additional odontoplasty being required. The beaver continued to feed normally with just the left maxillary and mandibular incisor teeth until its death at 118-months, with odontoplasty performed twice on the remaining incisor teeth during the 30-months following exfoliation.
Della Sala, S W; Recla, M; Campolongo, F; Bortot, G; Bauer, M; Peterlongo, P
The authors report a case of giant cell tumour of the mandibular condyle, which is a rare finding. This tumour, studied using the main three radiological modalities (plain radiography, CT and MRI) showed characteristic radiological features of "giant cell tumour".
Celentano, Giuseppe; Longobardi, Annalisa; Cannavale, Rosangela; Perillo, Letizia
Treatment effects of lip bumpers alone include flaring of the mandibular incisors, distalization and uprighting of the mandibular first molars, and buccal expansion of the canines, premolars, and molar. Lip forces are transmitted through this appliance onto the molars. Moreover the lip bumper is able to derotate, expand or constrict, upright and reinforce the anchorage whereas torque control is lacking. Aim of this paper is the presentation of a new type of lip bumper that allows the molar torque control.
Zhang, Xiao-Juan; He, Li; Tian, Jie; Bai, Yu-Xing; Li, Song
Objective To assess the accuracy of anterior tooth movement using clear aligners in integrated three-dimensional digital models. Methods Cone-beam computed tomography was performed before and after treatment with clear aligners in 32 patients. Plaster casts were laser-scanned for virtual setup and aligner fabrication. Differences in predicted and achieved root and crown positions of anterior teeth were compared on superimposed maxillofacial digital images and virtual models and analyzed by Student's t-test. Results The mean discrepancies in maxillary and mandibular crown positions were 0.376 ± 0.041 mm and 0.398 ± 0.037 mm, respectively. Maxillary and mandibular root positions differed by 2.062 ± 0.128 mm and 1.941 ± 0.154 mm, respectively. Conclusions Crowns but not roots of anterior teeth can be moved to designated positions using clear aligners, because these appliances cause tooth movement by tilting motion. PMID:26629473
Sancini, Angela; Tomei, Francesco; Tomei, Gianfranco; Caciari, Tiziana; Capozzella, Assunta; Di Famiani, Manuela; Samperi, Ilaria; Scala, Barbara; Fiaschetti, Maria; Cetica, Carlotta; Ciarrocca, Manuela
The aims of this study are to evaluate the prevalence of disorders of the lumbar region and the temporo-mandibular district co-morbidity in drivers and workers of the State Police employed for different office activities. The study population included 103 drivers as cases and 100 police officers as controls. The study was carried out through questionnaire and clinical evaluation of the spine and temporo-mandibular region. At clinical examination, the drivers were found to have a higher prevalence (p < 0.05) of both symptoms and clinical signs at the spine and temporo-mandibular joint (TMJ), when compared with the controls. The results also showed a higher prevalence (p < 0.05) of co-morbidity in the two districts among the drivers, when compared with the controls. These results confirm that morbidity related to back and TMJ and increase in co-morbidity between the two districts are higher in professional drivers.
de Oliveira, Simone Helena Gonçalves; de Moraes, Luiz César; Faig-Leite, Horácio; Camargo, Samira Esteves Afonso; Camargo, Carlos Henrique Ribeiro
Objective: The aim of this study was to verify, in vivo and in vitro, the prevalence of root canal bifurcation in mandibular incisors by digital radiography. Material and Methods: Four hundred teeth were analyzed for the in vivo study. Digital radiographs were taken in an orthoradial direction from the mandibular incisor and canine regions. The digital radiographs of the canine region allowed visualizing the incisors in a distoradial direction using 20° deviation. All individuals agreed to participate by signing an informed consent form. The in vitro study was conducted on 200 mandibular incisors positioned on a model, simulating the mandibular dental arch. Digital radiographs were taken from the mandibular incisors in both buccolingual and mesiodistal directions. Results: The digital radiography showed presence of bifurcation in 20% of teeth evaluated in vitro in the mesiodistal direction. In the buccolingual direction, 17.5% of teeth evaluated in vivo and 15% evaluated in vitro presented bifurcation or characteristics indicating bifurcation. Conclusions: Digital radiography associated with X-ray beam distally allowed detection of a larger number of cases of bifurcated root canals or characteristics of bifurcation. PMID:19466258
Rojas, René A; Julián, Gerardo; Lankin, Jorge
Facial trauma has reached a peak in the last decades in the world; however, scanty epidemiological information is available in Chile. To report the experience in the treatment of mandibular fractures in the maxillofacial unit at Hospital del Trabajador, Santiago. A retrospective study of patients with mandibular fractures treated in a seven years period (1990-1996). Demographic and clinical aspects of the patients are analyzed, with emphasis in causes of trauma, anatomic distribution of the fractures, treatment and complications. One hundred and sixty patients (aged 14 to 65 years old) sustained 245 mandibular fractures. Road traffic accidents were the most common cause of fractures (46%). The most common mandibular fracture was subcondylar. Thirty eight patients (24%) presented with associated facial fractures, while 34 (21%) had also other non-facial fractures. Open reduction and internal fixation was performed in 88 subjects. Complications occurred in 60 patients (38%). Road traffic accidents are the main cause of mandibular fractures in this series of patients. The most common mandibular fracture is subcondylar, which can be linked to the high rate of occlusal complications observed.
Marchetti, Claudio; Degidi, Marco; Scarano, Antonio; Piattelli, Adriano
A 17-year-old boy underwent three cycles of chemotherapy and a subsequent mandibular resection for a Ewing's sarcoma of the left body and ramus. The mandible was immediately reconstructed with a microvascular osteomuscular fibular flap. One year after the mandibular reconstruction, distraction osteogenesis of the anterior portion of the fibula was performed using a Martin distractor according to the Hoffmeister technique. Bone lengthening was achieved at a rate of 1 mm/day by turning the device twice each day for 12 days. Subsequently, we waited for 70 days for bone consolidation to occur. After 6 additional weeks, five Maestro implants were placed into the distracted fibula. Bone specimens were retrieved with a trephine bur during implant placement. Mature bone was present after 70 days and after 6 months. The bone height increase was 12 mm.
Monteith, Brian D
Reports of irreversible alteration in jaw posture and destructive occlusal contact relationships in individuals using mandibular advancement devices for obstructive sleep apnea are beginning to appear. This study sought cephalometric means of identifying such individuals before commencing therapy. Cephalograms of 34 obstructive sleep apnea sufferers who had worn mandibular advancement devices for 2 years were compared retrospectively with baseline films taken at commencement of therapy and analyzed for signs of morphologic changes in jaw position and occlusal relationship. In affected patients, two distinct morphologic species of mandibular reposturing became evident: (1) bilateral posterior open bite with destructive incisal attrition; and (2) less destructive intermediate open bite over the premolar and first molar regions. From the observed morphology patterns, gonial angle and maxillary-mandibular plane angle were analyzed as possible vertical cephalometric risk predictors, with newly defined pterygoid advancement proportion (PtAP) as a horizontal predictor. Three patients displayed the posterior open bite pattern and had gonial angles < or = 119 degrees and maxillary-mandibular plane angles < or = 16 degrees, with PtAP values > or = 0.48. Prediction intervals for the five intermediate open bite cases were 118 degrees < or = gonial angle < or = 128 degrees, and 23 degrees < or = maxillary-mandibular plane angle < or = 32 degrees. PtAP values were > or = 0.52. Cephalometric analysis can help practitioners identify which apnea patients might be likely to develop irreversible mandibular postural changes from wearing a jaw-repositioning device.
Krennmair, Gerald; Seemann, Rudolf; Weinländer, Michael; Wegscheider, Walther; Piehslinger, Eve
The aim of this retrospective study was to evaluate implant survival/success rates and peri-implant parameters as well as patient satisfaction for uniformly designed implant-supported anterior maxillary or mandibular fixed partial dentures (FPDs). A retrospective study was conducted on patients with maxillary or mandibular anterior partial edentulism (all incisors missing) treated between 2002 and 2006 with a two-implant-supported four-unit FPD. All FPDs were of the same design: two implant abutments in the lateral incisor positions and two ovate pontics in the central incisor positions. Cumulative implant survival rates and peri-implant conditions (marginal bone loss, pocket depth, Plaque Index, Gingival Index, Bleeding Index, Periotest values) as well as the incidence and type of prosthodontic maintenance were evaluated. The patients' subjective satisfaction rate was surveyed using multiple questionnaires with a 10-point scoring system (0 = not satisfied to 10 = highly satisfied). Thirty-six of 38 patients (dropout: 5%) with 72 implants (50 maxillary and 22 mandibular implants, 25 maxillary and 11 mandibular FPDs) were available for follow-up after a mean observation period of 56.2 ± 10.3 months. High cumulative implant survival and success rates (100%) and healthy peri-implant parameters (mean marginal bone resorption: 1.8 ± 0.3 mm; mean pocket depth: 2.5 ± 1.0 mm; Periotest value: -4.5 ± 1.1; and Plaque/Bleeding/Gingival indices of 0 in 70% of sites [with significantly better results in the maxilla than in the mandible]) were achieved. The most frequent required prosthodontic maintenance efforts were maxillary recementation (3/25; 12%) and mandibular rebasing (2/11; 18.2%). A high score for satisfaction was obtained, although slightly better overall results were seen for maxillary than for mandibular FPDs. For all parameters evaluated, these FPDs proved to be a viable treatment procedure for anterior partial edentulism with good clinical and esthetic
Wen, Xi; Wang, Xiyu; Qin, Shuqi; Franchi, Lorenzo; Gu, Yan
To compare the three-dimensional (3D) morphology of the upper airway in skeletal Class III patients with and without mandibular asymmetry and to investigate the possible underlying correlations between the morphology of the upper airway and mandibular deviation. Cone-beam computed tomography images of 54 subjects with skeletal Class III malocclusion (ANB angle ≤ 0.4°, Wits ≤ -5.5°) were taken and 3D upper airway models were reconstructed using Dolphin 3D software. According to the distance (d) from symphysis menti to the sagittal plane, all subjects were divided into a symmetry group (d ≤ 2 mm) and an asymmetry group (d ≥ 4 mm). Based on the severity of mandibular deviation, the asymmetry group was divided into subgroup I (4 mm ≤d <10 mm) and subgroup II (d ≥ 10 mm). Cross-sectional linear distances, areas, and volumetric variables of the upper airway were measured in the 3D airway model. Width of the inferior limit of the glossopharynx (P3W), cross-sectional area of the anterior limit of the nasal airway (P5S), and height of the glossopharynx (GPH) in the asymmetry group were significantly larger than in the symmetry group. As for subjects with severe mandibular deviation in subgroup II (d ≥ 10 mm), volume of the glossopharynx (GPV), total volume of the pharynx (TPV), length of the inferior limit of the velopharynx (P2L), and ratio of length to width of the inferior limit of the velopharynx (P2L/P2W) showed significantly negative correlations with mandibular deviation (r > 0.7, P < .05). In Class III subjects with severe mandibular asymmetry, the pharyngeal airway showed a tendency toward constriction and presented a more elliptical shape as mandibular deviation became more severe (P < .01).
Kim, Dokyung; Jin, Myoung-Uk
Objectives The purpose of this study was to evaluate the proximity of the mandibular molar apex to the buccal bone surface in order to provide anatomic information for apical surgery. Materials and Methods Cone-beam computed tomography (CBCT) images of 127 mandibular first molars and 153 mandibular second molars were analyzed from 160 patients' records. The distance was measured from the buccal bone surface to the root apex and the apical 3.0 mm on the cross-sectional view of CBCT. Results The second molar apex and apical 3 mm were located significantly deeper relative to the buccal bone surface compared with the first molar (p < 0.01). For the mandibular second molars, the distance from the buccal bone surface to the root apex was significantly shorter in patients over 70 years of age (p < 0.05). Furthermore, this distance was significantly shorter when the first molar was missing compared to nonmissing cases (p < 0.05). For the mandibular first molars, the distance to the distal root apex of one distal-rooted tooth was significantly greater than the distance to the disto-buccal root apex (p < 0.01). In mandibular second molar, the distance to the apex of C-shaped roots was significantly greater than the distance to the mesial root apex of non-C-shaped roots (p < 0.01). Conclusions For apical surgery in mandibular molars, the distance from the buccal bone surface to the apex and apical 3 mm is significantly affected by the location, patient age, an adjacent missing anterior tooth, and root configuration. PMID:27508159
Ma, Serina Yok Ling; Whittle, Terry; Descallar, Joseph; Murray, Greg M; Darendeliler, M Ali; Cistulli, Peter; Dalci, Oyku
The muscles of mastication are important in positioning the mandible and can therefore affect the patency of the upper airway. The aim of this study was to determine whether resting masticatory muscle activity influences the response to mandibular advancement splint treatment in patients with obstructive sleep apnea. Thirty-eight adult patients with obstructive sleep apnea were recruited for the study. Baseline electromyographic activities of the right anterior and posterior temporalis, masseter, and submandibular muscles were recorded with surface electrodes while the patients were awake, in the upright and supine positions, with the jaw in the postural position, and with and without a mandibular advancement splint. Muscle activity of the patients with obstructive sleep apnea was compared between responders (apnea-hypopnea index change ≥50%, and <10 events per hour) and nonresponders (apnea-hypopnea index change <50%) to mandibular advancement splint treatment. There were 18 responders and 20 nonresponders to mandibular advancement splint treatment. The responders had a trend for increased muscle activity in all muscle groups and scenarios. The resting muscle activity of the submandibular and masseter muscles while lying at rest and of the submandibular and posterior temporalis muscles while lying with the mandibular advancement splint in place were significantly greater (P <0.05) in the responders than in the nonresponders. Inherent baseline differences in muscle activity between responders and nonresponders to mandibular advancement splint treatment in adults with obstructive sleep apnea were observed. This preliminary study suggests that there might be a correlation between responsiveness with mandibular advancement splint treatment and baseline muscle activity. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.
Tooth impaction is a pathological situation where a tooth fails to attain its normal functional position. Impacted third molars are commonly encountered in routine dental practice. The impaction rate is higher for third molars when compared with other teeth. The mandibular third molar impaction is said to be due to the inadequate space between the distal of the second mandibular molar and the anterior border of the ascending ramus of the mandible. Impacted teeth may remain asymptomatic or may be associated with various pathologies such as caries, pericoronitis, cysts, tumors, and also root resorption of the adjacent tooth. Even though various classifications exist in the literature, none of those address the combined clinical and radiologic assessment of the impacted third molar. Literature search using the advanced features of various databases such as PubMed, Scopus, Embase, Google Scholar, Directory of Open Access Journals and Cochrane electronic databases was carried out. Keywords like impaction, mandibular third molar, impacted mandibular third molar, complications, anatomy, inferior alveolar nerve injury, lingual nerve injury were used to search the databases. A total of 826 articles were screened, and 50 articles were included in the review which was obtained from 1980 to February 2015. In the present paper, the authors have proposed a classification based on clinical and radiological assessment of the impacted mandibular third molar.
Tooth impaction is a pathological situation where a tooth fails to attain its normal functional position. Impacted third molars are commonly encountered in routine dental practice. The impaction rate is higher for third molars when compared with other teeth. The mandibular third molar impaction is said to be due to the inadequate space between the distal of the second mandibular molar and the anterior border of the ascending ramus of the mandible. Impacted teeth may remain asymptomatic or may be associated with various pathologies such as caries, pericoronitis, cysts, tumors, and also root resorption of the adjacent tooth. Even though various classifications exist in the literature, none of those address the combined clinical and radiologic assessment of the impacted third molar. Literature search using the advanced features of various databases such as PubMed, Scopus, Embase, Google Scholar, Directory of Open Access Journals and Cochrane electronic databases was carried out. Keywords like impaction, mandibular third molar, impacted mandibular third molar, complications, anatomy, inferior alveolar nerve injury, lingual nerve injury were used to search the databases. A total of 826 articles were screened, and 50 articles were included in the review which was obtained from 1980 to February 2015. In the present paper, the authors have proposed a classification based on clinical and radiological assessment of the impacted mandibular third molar. PMID:26229709
It is well known that a decrease in vertical height and in horizontal width is seen after tooth extraction. Immediate implant placement, originally thought to prevent buccal wall resorption, showed little or no evident decrease of the resorption rate or pattern in animal experiments or clinical studies. Thus, the need for bone augmentation with immediate implantation has been suggested. However, until recently, simultaneous bone augmentation with immediate implant placement was thought to be possible only in a submerged environment. In this report, the harmony of soft and hard tissue was achieved in 3 patients by immediate implant placement and bone augmentation with transmucosal healing in esthetically challenging situations. Further evaluation is needed to monitor hard- and soft-tissue changes on a long-term basis. Implant placement and bone augmentation with transmucosal healing using demineralized bone matrix may be an option in the treatment of the loss of anterior teeth.
Eshghpour, M; Nezadi, A; Moradi, A; Shamsabadi, R Mahvelati; Rezaei, N M; Nejat, A
Impacted teeth, if left untreated, have a potential to induce various complications. The aim of the current study was to determine the prevalence and pattern of impacted mandibular third molar in the Iranian population. This cross-sectional study was performed in patients who were referred to the Department of Oral Radiology between July 2009 and October 2010 to obtain an orthopantomogram (OPG). Data were collected regarding age and gender, prevalence of impacted mandibular third molars, angulation of impacted teeth (Winter's classification), level of impaction (Pell and Gregory classification), and relationship of the mandibular third molar with the ramus (Pell and Gregory classification). The collected data were analyzed using SPSS software version 11.0 with a confidence interval of 95%. Among the 1433 patients included in the study, 489 (34.12%) patients were male and 944 (65.88%) were female. Of the total OPGs performed, 871 (60.78%) OPGs demonstrated at least one impacted mandibular third molar. In addition, of the 2866 mandibular third molars investigated, 1397 (48.74%) were found to be impacted. A significant association was observed between gender and the number of impacted teeth or the presence of impaction of any mandibular tooth (or teeth) (P < 0.05). The most common type of tooth angulation was mesioangular (48.67%). In addition, the most prevalent type of impaction level and ramus relationship was level B (63.85%) and Class II (48.46%), respectively. There were no significant differences between the two sides of the mandible for the prevalence of impacted third molar (P > 0.05). The pattern of mandibular third molars in the Northeast region of Iran revealed a high prevalence of impaction, which was mostly mesioangular, level B, and Class II with a gender predilection for females.
Swart, Louwrens C; Dreyer, Wynand P; van Zyl, Paul P; Blignaut, Renette J
This prospective study was undertaken to evaluate the 10-year implant survival rate as well as bone remodeling for immediately loaded anterior mandibular implants. Patients with nonrestorable anterior mandibular teeth were enrolled. All mandibular teeth were extracted, and five rough-surfaced (titanium plasma spray) one-piece implants were placed, evenly spread between the mental foramina. All implants were immediately loaded with a provisional prosthesis. A definitive prosthesis was . Eight patients received 40 implants, 30 in extraction sockets and 10 in healed sites. All but two implants that did not achieve primary stability (35 Ncm) were immediately loaded. The progress of seven patients was evaluated after 10 years. The mean age at implant placement was 60 years, and the length of follow-up varied between 10.3 and 11.47 years. The results showed a 100% implant retention rate; however, clinically observed bone loss around two central implants led to consideration for future surgical intervention or removal. Average bone loss was < 1 mm, and little difference was noted between implants placed in healed sites and those placed in extraction sockets. Technical problems with the prostheses were confined to two patients; one patient had seven fractures and the other had one. Rough-surfaced implants placed in extraction sockets between the mental foramina and immediately loaded can be successful in the long term. Because only is recommended that this site be avoided when immediately loaded implants are to be used in the anterior mandible.
Siu, Yuk Chuen; Lui, Tun Hing
Introduction: Unilateral anterior shoulder dislocation is one of the most common problems encountered in orthopedic practice. However, simultaneous bilateral anterior dislocation of the shoulders is quite rare. Case Presentation: We report a case of a 75-year-old woman presented with simultaneous bilateral anterior shoulder dislocation following a trauma, complicated with a traction injury to the posterior cord of the brachial plexus. Conclusions: Bilateral anterior shoulder dislocation is very rare. The excessive traction force during closed reduction may lead to nerve palsy. Clear documentation of neurovascular status and adequate imaging before and after a reduction should be performed. PMID:25685749
Marşan, Gülnaz; Aksu, Irem Sakarya; Kurt, Hanefi; Kuvat, Samet Vasfi; Cura, Nil
An adult woman with amelogenesis imperfecta, a skeletal Class III relationship, long face syndrome, and a severe anterior open bite received interdisciplinary treatment (orthodontics, orthognathic surgery, and prosthodontics). Presurgical orthodontic treatment was followed by a maxillary posterior impaction with anterior advancement and a mandibular setback. After surgery, the patient received ceramic crowns. Function and esthetics were successfully re-established. © 2010 BY QUINTESSENCE PUBLISHING CO, INC.
Ohba, Seigo; Kohara, Haruka; Koga, Takamitsu; Kawasaki, Takako; Miura, Kei-Ichirou; Yoshida, Noriaki; Asahina, Izumi
The soft tissue profile is crucial to esthetics after orthognathic surgery. The aim of this study was to assess the soft tissue changes of the subnasal and submental regions more than 1 year after a sagittal split ramus osteotomy (SSRO) in patients with skeletal class III malocclusion. A total of 22 patients with mandibular prognathism were included in this study. Patients had lateral cephalograms before and more than 1 year after they underwent an isolated SSRO. Soft and hard tissue changes were assessed using the lateral cephalograms. The lower lip, labiomenton, and soft tissue menton moved posteriorly by 85, 89, and 88% compared with the corresponding hard tissue, and the movement of the soft tissue B point and the top of the chin nearly reflected the displacement of the hard tissues, at 96 and 99%, respectively. The labiomenton, stomions, and naso-labial angles were changed after the mandibular set-back and the changes in these angles correlated with either the width of the soft tissue or skeletal displacement. The naso-labial angle could be altered even if an isolated mandibular osteotomy is performed. Changes to the stomions and naso-labial angles were affected by hard tissue movement, while changes to the labiomental angle were affected by the width of the soft tissue after the mandibular osteotomy. It is important to create an accurate preoperative prediction of the esthetic outcomes after a mandibular osteotomy by considering the interrelations between the hard and soft tissues.
Olsen, K R; Matzen, L H; Vaeth, M; Wenzel, A
Objectives: This epidemiological study aimed to analyse economical and societal consequences in Denmark if CBCT is used routinely as a diagnostic method before removal of the mandibular third molar. Furthermore, the aim was to calculate the excess cancer incidence from this practice. Methods: 17 representative dental clinics in the regions of Denmark were visited by two observers, who registered the total number of patients in each clinic, the number of removed mandibular third molars from patients' files together with the age and gender of these patients. The data were collected from 2008 to 2014. The total number of removed mandibular third molars in Denmark each year was derived from the collected data and information on patients' contacts with dentists from Statistics Denmark as a sum of contributions from each region. The contribution of a region was obtained as the number of removed mandibular third molars in the selected clinics in the region times the ratio of the number of patients in the selected clinics in the region to the total number of patients with contact to a general practitioner in the region in 2011. Existing knowledge on the costs for panoramic and CBCT imaging was used to calculate total costs. The cancer incidence was calculated from lifetime attributable risk curves based on linear risk assumptions. Results: The selected clinics included 109,686 patients, and 1369 mandibular third molars had been surgically removed. Using data from Statistics Denmark gave an estimated annual number of removed mandibular third molars of 36,882 at a total cost of €6,633,400. The additional cancer incidence was estimated to be approximately 0.46 per year. Conclusions: The data should be used in a cost-effectiveness analysis of the clinical efficacy of CBCT imaging before removal of mandibular third molars. PMID:25785820
Reyes Court, Daniel; Encina, Susana; Levy, Irene
Metastatic lesions of primary tumors, which originate in different parts of the body, comprise almost 1 % of different types of oral cancers. These lesions can affect either bones or soft tissues in the maxillofacial region. Whenever the maxillofacial area is affected, the most common location is in the molar region of the mandible. The clinical presentation of mandibular metastasis follows a clinical pattern characterized by irradiated dental pain in the third molar region. The most frequent sign is parethesia of the area innervated by the mandibular alveolar dental nerve. Differential diagnosis and treatment of these patients can be extremely difficult because there a number of pathologic conditions with similar symptoms and because diagnostic examination can be highly confusing. The aim of this article is to present a case of prostatic adenocarcinoma where the only metastasis was found in the jaw. A literature review will be presented, hoping to contribute to the scarce information regarding this lesion, due to its low frequency and atypical expression of this type of metastasis in terms of etiology, biological behavior and treatment.
TORRES, Fernando César; de ALMEIDA, Renato Rodrigues; de ALMEIDA-PEDRIN, Renata Rodrigues; PEDRIN, Fernando; PARANHOS, Luiz Renato
Objective The aim of this prospective study was to compare the dentoalveolar effects produced by two types of palatal crib, removable (Rpc+C) and fixed (Fpc+C), combined with chincup in growing patients with anterior open bite. Material and Methods Each group comprised 30 patients, in the mixed dentition phase, with similar cephalometric characteristics and skeletal ages. Group 1 (Rpc+C) presented initial mean age of 8.3 years and mean anterior open bite of 4.0 mm. Group 2 (Fpc+C) presented initial mean age of 8.54 years and mean anterior open bite of 4.3 mm. The evaluation period comprised 12 months between initial (T1) and second lateral radiograph (T2). The T2-T1 changes were compared cephalometrically in the 2 groups using the non-paired t-test. Results Vertical changes in the posterior dentoalveolar region were similar between the groups (about 1 mm) and no significant differences were found in molar mesialization. The Fpc+C group had in average 1.6 mm more improvement of the overbite as a result of greater maxillary incisor extrusion (1.3 mm). Patients in this group also presented less lingual tipping of maxillary incisors and more mandibular incisors uprighting. Conclusions The Fpc+C combination was more efficient in the correction of the negative overbite mainly due to greater extrusion of the maxillary incisors. However, the Rpc+C appliance promoted better upper and lower incisor inclination, resulting in a more adequate overjet. PMID:23138739
Şahan, Murat; Derin, Serhan; Beydilli, Halil; Çullu, Neşet
The mandibular condyle region which protects the middle cranial fossa from facial and jaw traumas has an excellent osteomuscular structure. Condylar structures reduce or limit the force of trauma. Most importantly, the condylar neck is the weakest part of the mandible and is easily fractured without dislocation. Generally, this mechanism prevents condylar penetration into the middle cranial fossa; however, there are condylar penetration into the middle cranial fossa can be rarely. Glenoid fossa fractures without mandibular condylar fracture and dislocation can be made. In this article, we present two cases to assess the isolated glenoid fossa fractures of the temporal bone.
Bargale, Seema D; Kiran, Shital D P
Abnormalities in size of teeth and number of teeth are occasionally recorded in clinical cases. True generalized microdontia is rare case in which all the teeth are smaller than normal. Mesiodens is commonly located in maxilary central incisor region and uncommon in the mandible. In the present case a 12 year-old boy was healthy; normal in appearance and the medical history was noncontributory. The patient was examined and found to have permanent teeth that were smaller than those of the average adult teeth. The true generalized microdontia was accompanied by mandibular mesiodens. This is a unique case report of non-syndromic association of mandibular hyperdontia with true generalized microdontia.
Chang, Jenny Zwei-Chieng; Chen, Yi-Jane; Chang, Frank Hsin-Fu; Yao, Jane Chung-Chen; Liu, Pao-Hsin; Chang, Chih-Han; Lan, Wan-Hong
The craniofacial growth patterns of untreated individuals with skeletal Class III malocclusion have rarely been systemically investigated. This study used morphometric techniques to investigate the growth characteristics of the mandible in individuals with skeletal Class III malocclusion. Lateral cephalometric head films of 294 individuals with untreated skeletal Class III malocclusion (134 males, 160 females) were selected and divided into five triennial age groups (T1-T5) and by gender to identify the morphologic characteristics and sexual dimorphism in changes of mandibular growth. Procrustes, thin-plate spline, and finite element analyses were performed for localization of differences in shape and size changes. Maximum and minimum principal axes were drawn to express the directions of shape changes. From T1 (age 6-8 years) to T4 (age 15-17 years), the distribution of localized size and shape changes of the mandible was very similar between the two genders. From T1 to T2 (age 9-11 years), significant lengthening of the condylar region was noted (23.4-39.7%). From T2 to T3 (age 12-14 years), the greatest size and shape change occurred at the condylar head (27.4-34.9%). From T3 to T4, the greatest size and shape changes occurred in the symphyseal region (23.6-42.1%). From T4 to T5 (age>or=18 years), significant sexual dimorphism was found in the distribution and amount of localized size and shape changes. Females displayed little growth increments during T4. Despite differences in the remodeling process, the whole mandibular configurations of both genders exhibited similarly significant upward and forward deformation from T4 to T5. We conclude that thin-plate spline analysis and the finite element morphometric method are efficient for the localization and quantification of size and shape changes that occur during mandibular growth. Plots of maximum and minimum principal directions can provide useful information about the trends of growth changes.
Carlino, Franco; Pantaleo, Giuseppe; Ciuffolo, Fabio; Claudio, Pier Paolo; Cortese, Antonio
A surgical technique to widen the mandible is the mandibular midline distraction: the most common indications for mandibular midline distraction are severe mandibular anterior crowding, severe mandibular transverse deficiency, uni- or bilateral crossbite, impacted anterior teeth with inadequate space, and tipped teeth. Commonly used distraction devices can be divided into 2 systems: bone-borne distraction system appliance, dental-borne distraction systems. Each system has peculiar advantages, disadvantages, and different indications. To combine advantages of both systems we developed a new technique adopting an immediate basal bone widening with fixation after osteotomy and a dental borne rigid lingual system for distraction. The aim of this work is to show a new technique for symphysis mandibular distraction based on a double-level anchorage and fixation system on clinical patients showing final results and advantages. Two patients affected by dento-alveolar and basal bone maxillary and mandibular transversal collapse even in association with other skeletal malocclusion were selected. Patients were clinically and radiographically studied and analyzed at different times before and after surgery. Dental and basal bone measurements were performed clinically and radiographically. The results were optimal with perfect dental arches alignment followed by closing of the open bites with multiple-segmented surgery in a second surgical time. No misalignment of the 2 mandibular halves was noticed during the distraction procedure. Dental-bone discrepancies correction is mandatory before orthodontic treatment alignment. Transversal jaw expansion can be achieved safely and stably by distraction of both maxillae for the combination of osteogenesis and histogenesis with augmentation of both bone and soft tissue. Bone-borne distraction will result in more stable results; dental-borne devices will result in more simple and aesthetically rewarding procedures. Hybrid techniques
Forder, John R.; Clark, Dan; Shih, Andre; Udassi, Sharda; Badugu, Srinivasarao; Lamb, Melissa A.; Porvasnik, Stacy L.; Shih, Renata S.; Colon-Lopez, Dalia; Zaritsky, Arno L.
Objective. Decreased cardiac function after resuscitation from cardiac arrest (CA) results from global ischemia of the myocardium. In the evolution of postarrest myocardial dysfunction, preferential involvement of any coronary arterial territory is not known. We hypothesized that there is no preferential involvement of any coronary artery during electrical induced ventricular fibrillation (VF) in piglet model. Design. Prospective, randomized controlled study. Methods. 12 piglets were randomized to baseline and electrical induced VF. After 5 min, the animals were resuscitated according to AHA PALS guidelines. After return of spontaneous circulation (ROSC), animals were observed for an additional 4 hours prior to cardiac MRI. Data (mean ± SD) was analyzed using unpaired t-test; p value ≤ 0.05 was considered statistically significant. Results. Segmental wall motion (mm; baseline versus postarrest group) in segment 7 (left anterior descending (LAD)) was 4.68 ± 0.54 versus 3.31 ± 0.64, p = 0.0026. In segment 13, it was 3.82 ± 0.96 versus 2.58 ± 0.82, p = 0.02. In segment 14, it was 2.42 ± 0.44 versus 1.29 ± 0.99, p = 0.028. Conclusion. Postarrest myocardial dysfunction resulted in segmental wall motion defects in the LAD territory. There were no perfusion defects in the involved segments. PMID:27882326
Guven, Yeliz; Zorlu, Sevgi; Cankaya, Abdulkadir Burak; Aktoren, Oya; Gencay, Koray
The principles of management of mandibular fractures differ in children when compared to adults and depend on the specific age-related status of the growing mandible and the developing dentition. This paper presents a case report with a complex facial trauma affecting the mandibular body and condyle region and dentoalveolar complex. Clinical examination revealed soft tissue injuries, limited mouth opening, lateral deviation of the mandible, an avulsed incisor, a subluxated incisor, and a fractured crown. CBCT examination revealed a nondisplaced fracture and an oblique greenstick fracture of the mandibular body and unilateral fracture of the condyle. Closed reduction technique was chosen to manage fractures of the mandible. Favorable healing outcomes on multiple fractures of the mandible throughout the 6-year follow-up period proved the success of the conservative treatment. This case report is important since it presents a variety of pathological sequelae to trauma within one case.
Zhu, Min; Liu, Chao; Ren, Shuangshuang; Lin, Zintong; Miao, Leiying; Sun, Weibin
Gemination or fusion is a rare occurrence in the mandibular posterior teeth. The aim of this article is to describe the problems encountered and the strategy employed in treating such cases. A 34 years old patient came with the complaint of spontaneous and radiating pain in the right mandibular posterior region. The tooth in concern was an anomalous ‘double’ second mandibular molar diagnosed as having necrotic pulp with chronic apical abscess of endodontic origin. The present case emphasizes the importance of identifying anatomical anomalies during treatment of fused teeth with supernumerary tooth, and the need for the use of advanced imaging modalities like CBCT which is a critical aid in the diagnosis of such cases. Fused teeth can be managed quite efficiently by an overall combined treatment including both endodontic and periodontal therapy. PMID:26550101
Zorlu, Sevgi; Cankaya, Abdulkadir Burak; Aktoren, Oya; Gencay, Koray
The principles of management of mandibular fractures differ in children when compared to adults and depend on the specific age-related status of the growing mandible and the developing dentition. This paper presents a case report with a complex facial trauma affecting the mandibular body and condyle region and dentoalveolar complex. Clinical examination revealed soft tissue injuries, limited mouth opening, lateral deviation of the mandible, an avulsed incisor, a subluxated incisor, and a fractured crown. CBCT examination revealed a nondisplaced fracture and an oblique greenstick fracture of the mandibular body and unilateral fracture of the condyle. Closed reduction technique was chosen to manage fractures of the mandible. Favorable healing outcomes on multiple fractures of the mandible throughout the 6-year follow-up period proved the success of the conservative treatment. This case report is important since it presents a variety of pathological sequelae to trauma within one case. PMID:26339511
Raberin, Monique; Cozor, Ilinca; Gobert-Jacquart, Stéphanie
A study of mandibular growth maturation was performed on a population of 103 patients during orthodontic treatment (69 girls and 34 boys) from 11 to 16 years, having initially a Class II skeletal discrepancy. The relationship between wrist maturation indices and the cervical vertebrae maturation was studied by Lamparski classification. Significant correlations were found between Björk stages, MP3=, MP3 cap and MP3 U and respectively Lamparski stages as CVS 2, CVS 3-4 and CVS 5-6. This retrospective longitudinal study identified three mandibular variables at three different maturation stages according to Björk classification and to the six stages of Lamparski classification. The relationships between these different maturation stages and a quantitative mandibular response permit to estimate optimal time for our orthodontic therapy. The results indicate a significant increase in mandibular length between CVS 4 and CVS 5, suggesting the persistence of a condylar response to a stimulation therapy after CVS3 or CVS 4 stages (MP3 cap). Mandibular growth seems to continue after MP3 U stage or CVS 5 stage. © EDP Sciences, SFODF, 2012.
Meyer, Michael A.
In an effort to find possible new gene candidates involved in the causation of amyotrophic lateral sclerosis (ALS), a prior version of the on-line brain gene expression atlas GENSAT was extensively searched for selectively intense expression within spinal motor neurons. Using autoradiographic data of in-situ hybridization from 3430 genes, a search for selectively intense activity was made for the anterior horn region of murine lumbar spinal cord sectioned in the axial plane. Of 3430 genes, a group of 17 genes was found to be highly expressed within the anterior horn suggesting localization to its primary cellular constituent, the alpha spinal motor neuron. For some genes, an inter-relationship to ALS was already known, such as for heavy, medium, and light neurofilaments, and peripherin. Other genes identified include: Gamma Synuclein, GDNF, SEMA3A, Extended Synaptotagmin-like protein 1, LYNX1, HSPA12a, Cadherin 22, PRKACA, TPPP3 as well as Choline Acetyltransferase, Janus Kinase 1, and the Motor Neuron and Pancreas Homeobox 1. Based on this study, Fibroblast Growth Factor 1 was found to have a particularly selective and intense localization pattern to the ventral horn and may be a good target for development of motor neuron disease therapies; further research is needed. PMID:24987504
Meyer, Michael A
In an effort to find possible new gene candidates involved in the causation of amyotrophic lateral sclerosis (ALS), a prior version of the on-line brain gene expression atlas GENSAT was extensively searched for selectively intense expression within spinal motor neurons. Using autoradiographic data of in-situ hybridization from 3430 genes, a search for selectively intense activity was made for the anterior horn region of murine lumbar spinal cord sectioned in the axial plane. Of 3430 genes, a group of 17 genes was found to be highly expressed within the anterior horn suggesting localization to its primary cellular constituent, the alpha spinal motor neuron. For some genes, an inter-relationship to ALS was already known, such as for heavy, medium, and light neurofilaments, and peripherin. Other genes identified include: Gamma Synuclein, GDNF, SEMA3A, Extended Synaptotagmin-like protein 1, LYNX1, HSPA12a, Cadherin 22, PRKACA, TPPP3 as well as Choline Acetyltransferase, Janus Kinase 1, and the Motor Neuron and Pancreas Homeobox 1. Based on this study, Fibroblast Growth Factor 1 was found to have a particularly selective and intense localization pattern to the ventral horn and may be a good target for development of motor neuron disease therapies; further research is needed.
...) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... jaw for temporary reconstruction of the mandibular condyle in patients who have undergone resective...
Abnormalities in the root canal anatomy are commonly occurring phenomenon. A thorough knowledge of root canal anatomy and its variation is necessary for successful completion of endodontic treatment. Mandibular anteriors are known for having extra canals. The role of genetics and racial variations may result in difference of incidence of root number and canal number. This paper attempts at explaining a rare case of successful endodontic management of two-rooted lateral incisor with awareness of data pertaining to number of canals, knowledge of canal morphology, correct radiographic interpretation, and tactile examination of canal wall which are important in detecting the presence of multiple canals. PMID:27003981
Gallegos-Hernández, José Francisco; Reyes-Vivanco, Alejandro; Arias-Ceballos, Héctor; Minauro-Muñoz, Gerardo Gabriel; Ortiz-Maldonado, Alma Lilia; García-Ruiz, Daniel Israel; Hernández-Sanjuán, Martín
Osteoradionecrosis of the mandible is a relatively common complication in patients with head and neck cancer undergoing radiotherapy or concomitant chemoradiotherapy, characterized by exposure of the mandibular bone either in the mouth or in the facial skin, with no improvement with conservative treatment for six months. The risk factors are radiotherapy in head and neck region, lack of dental prophylaxis before treatment and dental extraction. Retrospective observational study analyzing incidence and etiologic factors of osteoradionecrosis in 250 patients undergoing radiotherapy or combined treatment of cervicofacial area between 2002 and 2010. 25 patients were included; the horizontal branch was the most affected area, followed by the anterior arch. Associated factors were: stage (T4a and T4b), tumor location (oral cavity), dental extraction pre or post-radiotherapy, and radiotherapy time (pre-or postoperative); 72% had association with tooth extraction. Only five patients had control with conservative measures, and 20 required some type of mandibulectomy, only three of them were candidates for reconstruction with fibular free flap; none received treatment in a hyperbaric chamber. The data suggest that osteoradionecrosis has a multifactorial origin, and prevention is the best alternative and includes pretreatment dental prophylaxis to avoid tooth extractions and close monitoring and surveillance in order to identify early osteoradionecrosis. Most patients require mandible resection as definitive treatment.
Jonasson, Grethe; Kiliaridis, Stavros
After tooth extraction there is a great interindividual variation in the remodelling pattern of the alveolar process in edentulous areas, with some individuals losing little bone and others undergoing extensive resorption. However, little is known about possible longitudinal changes in the dentate region of the alveolar process of adults and if these are related to alterations in the skeletal bone mineral density (BMD). In a prospective study, on two occasions, 5-yr apart, the BMD of 117 women was determined in the distal forearm by using dual-energy X-ray absorptiometry, and the bucco-lingual thickness of the mandibular alveolar process was measured on dental casts by using a dial calliper. A decrease in the mean alveolar thickness, exceeding a cut-off value of 0.1 mm, was found in 60% of the women and an increase was found in 3% of the individuals. This decrease was 0.22 +/- 0.20 mm in the posterior region and 0.16 +/- 0.19 mm in the anterior region. The changes in alveolar thickness in the posterior region were significantly correlated to the BMD changes both on the mid-crestal level site and on the cervical level site. We conclude that the bucco-lingual thickness decreases with age in the dentate alveolar process, possibly owing to periosteal resorption related to skeletal bone loss.
Benech, Arnaldo; Arcuri, Francesco; Baragiotta, Nicola; Nicolotti, Matteo; Brucoli, Matteo
There is a multitude of reported surgical approaches and technical variants with some unresolved technical problems to gain direct access to mandibular condylar head fractures; they can be divided into 2 groups: intraoral and extraoral. In 2005, Neff et al (Mund Kiefer Gesichtschir 2005;9:80), supported by a previous experimental work, reported a successful clinical study of condylar head fractures treated by a retroauricular approach; this article is in German, and the later English-language literature does not mention about this approach to open reduction and internal fixation of mandibular condylar fractures. The retroauricular transmeatal access, selected and performed by the senior author to treat 14 patients affected by highly located condylar head fracture, is illustrated in details. We collected data of 14 consecutive adult patients who, after the discussion about all options, had consented to have 16 mandibular condylar head fractures treated with open reduction and internal fixation by miniplates and screws via a retroauricular transmeatal approach. We exposed the temporomandibular joint area easily and better by dissecting via a retroauricular route with identification, ligation, and transection of the retromandibular vein; because of the posterior access, the frontal branch of the facial nerve and the auriculotemporal nerve are located and protected within the substance of the anteriorly retracted flap, superficial to the retromandibular vein. The follow-up clinical examination showed temporary weakness of the frontal branch of the facial nerve in 1 case with a recovery to normal function of 1.6 months; no patients had permanent weakness of the facial nerve or injury of the auriculotemporal nerve. There was absence of any salivary fistula, sialocele, and Frey syndrome; hearing was preserved in all cases, without any auditory stenosis or aesthetic deformity, and there was absence of any infections, hematoma, or scarring. Retroauricular approach provides
Vanden Berg-Foels, Wendy S.
Background Mandibular condyle cartilage (MCC) has a unique structure among articular cartilages; however, little is known about its nanoscale collagen network architecture, hampering design of regeneration therapies and rigorous evaluation of regeneration experiment outcomes in preclinical research. Helium ion microscopy is a novel technology with a long depth of field that is uniquely suited to imaging open 3D collagen networks at multiple scales without obscuring conductive coatings. Objective The objective of this research was to image, at the micro- and nanoscales, the depth-dependent MCC collagen network architecture. Design MCC was collected from New Zealand white rabbits. Images of MCC zones were acquired using helium ion, transmission electron, and light microscopy. Network fibril and canal diameters were measured. Results For the first time, the MCC was visualized as a 3D collagen fibril structure at the nanoscale, the length scale of network assembly. Fibril diameters ranged from 7 to 110 nm and varied by zone. The articular surface was composed of a fine mesh that was woven through thin layers of larger fibrils. The fibrous zone was composed of approximately orthogonal lamellae of aligned fibrils. Fibrocyte processes surrounded collagen bundles forming extracellular compartments. The proliferative, mature, and hypertrophic zones were composed of a branched network that was progressively remodeled to accommodate chondrocyte hypertrophy. Osteoid fibrils were woven around osteoblast cytoplasmic processes to create numerous canals similar in size to canaliculi of mature bone. Conclusion This multiscale investigation advances our foundational understanding of the complex, layered 3D architecture of the MCC collagen network. PMID:27375843
Darshan, S Vinay; Ronad, Yusuf Ahammed; Kishore, M S V; Shetty, K Sadashiva; Rajesh, M; Suman, S D
Background: The aim was to evaluate the long-term hard and soft tissue changes following mandibular advancement and setback surgeries. Materials and Methods: A total of 16 subjects each were selected who underwent bilateral sagittal split osteotomy mandibular advancement and mandibular setback groups. Pre-surgical (T1), immediate post-surgical (T2) and long-term post-surgical (T3) cephalograms were compared for hard and soft tissue changes. After cephalometric measurements, the quantity of changes between T1-T2 and T1-T3 were determined for each patient. The mean difference between T1-T2 and T1-T3 was compared with assess the long-term changes and stability. Results: In mandibular advancement the mean difference between immediate post-surgical and long term post-surgical is 7%, which accounts for a relapse of 7%. In mandibular setback, the mean difference between immediate post-surgical and long-term post-surgical is 29%, which accounts for a relapse of 29%. Conclusion: Mandibular advancement remained stable over the long period when compared to mandibular setback. PMID:25395792
Yassen, Ghaeth H
The objectives of this study were to determine the effectiveness of mandibular infiltration compared with mandibular block in treating primary canines in children and to relate the effectiveness to the type of treatment performed. A total of 89 children, 6-9 years old, requiring identical treatment on contralateral mandibular canines were selected. The split mouth study design was used. The anaesthetic used in both techniques was 2% lidocaine solution with 1 : 80,000 epinephrine. Dental procedures included class III, IV, and V restorations, formocresol pulpotomies, and extractions. Child's pain reaction and behaviour for each anaesthesia technique and the type of treatment were rated at certain intervals of treatment using sounds, motor, and ocular changes indicating pain and the Frankl Behaviour Rating Scale. Evaluations were made upon injection, probing, rubber dam placement, and during tooth preparation and extraction. No statistically significant difference was found between the two anaesthetic techniques for either pain or behaviour at all evaluation intervals (P > 0.05), during the performance of restorations, pulpotomies, or during extractions. Mandibular infiltration anaesthesia is as effective as mandibular block for restoration, pulpotomy, and extraction in primary canines. The mandibular infiltration anaesthesia was not significantly less painful than the mandibular block.
Gu, Xiaosi; Gao, Zhixian; Wang, Xingchao; Liu, Xun; Knight, Robert T.; Hof, Patrick R.
Empathy refers to the ability to perceive and share another person’s affective state. Much neuroimaging evidence suggests that observing others’ suffering and pain elicits activations of the anterior insular and the anterior cingulate cortices associated with subjective empathetic responses in the observer. However, these observations do not provide causal evidence for the respective roles of anterior insular and anterior cingulate cortices in empathetic pain. Therefore, whether these regions are ‘necessary’ for empathetic pain remains unknown. Herein, we examined the perception of others’ pain in patients with anterior insular cortex or anterior cingulate cortex lesions whose locations matched with the anterior insular cortex or anterior cingulate cortex clusters identified by a meta-analysis on neuroimaging studies of empathetic pain perception. Patients with focal anterior insular cortex lesions displayed decreased discrimination accuracy and prolonged reaction time when processing others’ pain explicitly and lacked a typical interference effect of empathetic pain on the performance of a pain-irrelevant task. In contrast, these deficits were not observed in patients with anterior cingulate cortex lesions. These findings reveal that only discrete anterior insular cortex lesions, but not anterior cingulate cortex lesions, result in deficits in explicit and implicit pain perception, supporting a critical role of anterior insular cortex in empathetic pain processing. Our findings have implications for a wide range of neuropsychiatric illnesses characterized by prominent deficits in higher-level social functioning. PMID:22961548
Chung, Seung-Won; Jung, Hwi-Dong; Park, Hyung-Sik; Jung, Young-Soo
Intraoral vertical ramus osteotomy (IVRO) is an effective surgical procedure that is used for the correction of mandibular prognathism. However, application of IVRO for mandibular advancement has been limited because of the instability of the proximal segments caused by the gap between the distal and proximal segments. We report a case of unilateral mandibular advancement with bilateral IVRO for the correction of facial asymmetry. This case shows possible application of bilateral IVRO for unilateral mandibular advancement without any means of fixation.
Singh, M; Detamore, M S
Mandibular condylar cartilage plays a crucial role in temporomandibular joint (TMJ) function, which includes facilitating articulation with the TMJ disc, reducing loads on the underlying bone, and contributing to bone remodeling. To improve our understanding of the TMJ function in normal and pathological situations, accurate and validated three-dimensional (3-D) finite element models (FEMs) of the human TMJ may serve as valuable diagnostic tools as well as predictors of thresholds for tissue damage resulting from parafunctional activities and trauma. In this context, development of reliable biomechanical standards for condylar cartilage is crucial. Moreover, biomechanical characteristics of the native tissue are important design parameters for creating functional tissue-engineered replacements. Towards these goals, biomechanical characteristics of the condylar cartilage have been reviewed here, highlighting the structure-function correlations. Structurally, condylar cartilage, like the TMJ disc, exhibits zonal and topographical heterogeneity. Early structural investigations of the condylar cartilage have suggested that the tissue possesses a somewhat transversely isotropic orientation of collagen fibers in the fibrous zone. However, recent tensile and shear evaluations have reported a higher stiffness of the tissue in the anteroposterior direction than in the mediolateral direction, corresponding to an anisotropic fiber orientation comparable to the TMJ disc. In a few investigations, condylar cartilage under compression was found to be stiffer anteriorly than posteriorly. As with the TMJ disc, further compressive characterization is warranted. To draw inferences for human tissue using animal models, establishing stiffness-thickness correlations and regional evaluation of proteoglycan/glycosaminoglycan content may be essential. Efforts directed from the biomechanics community for the characterization of TMJ tissues will facilitate the development of reliable and
Rehabilitating atrophied mandible with two-implant supported denture is a common treatment modality for implant retained removable overdenture in mandible. This paper aims to design a treatment modality where single implant reinforced overdenture is fabricated for a severely atrophied mandibular ridge with early loading protocol. Results of studies have shown that a single implant mandibular overdenture significantly increases the satisfaction and quality of life of patients with edentulism. Midline fracture of the prosthesis is the most common complication related to single implant and two-implant retained mandibular overdentures. To manage such complication, a thin metal mesh is used to reinforce the overdenture and also to make the prostheses lighter and cost effective as compared to conventional cast metal framework. PMID:27403350
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Mandibular condyle prosthesis. 872.3960 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw...
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Mandibular condyle prosthesis. 872.3960 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw...
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Mandibular condyle prosthesis. 872.3960 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw...
... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... requirement for premarket approval for any mandibular condyle prosthesis intended to be implanted in the human...
... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular implant facial prosthesis. (a) Identification. A mandibular implant facial prosthesis is a device that is intended to be implanted for use in the functional reconstruction of mandibular deficits. The device...
... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular implant facial prosthesis. (a) Identification. A mandibular implant facial prosthesis is a device that is intended to be implanted for use in the functional reconstruction of mandibular deficits. The device...
Lin, Qiuping; Huang, Xiaoqiong; Xu, Yue; Yang, Xiaoping
Purpose Facial asymmetry often persists even after mandibular deviation corrected by the bilateral sagittal split ramus osteotomy (BSSRO) operation, since the reference facial sagittal plane for the asymmetry analysis is usually set up before the mandibular menton (Me) point correction. Our aim is to develop a predictive and quantitative method to assess the true asymmetry of the mandible after a midline correction performed by a virtual BSSRO, and to verify its availability by evaluation of the post-surgical improvement. Patients and Methods A retrospective cohort study was conducted at the Hospital of Stomatology, Sun Yat-sen University (China) of patients with pure hemi-mandibular elongation (HE) from September 2010 through May 2014. Mandibular models were reconstructed from CBCT images of patients with pre-surgical orthodontic treatment. After mandibular de-rotation and midline alignment with virtual BSSRO, the elongation hemi-mandible was virtually mirrored along the facial sagittal plane. The residual asymmetry, defined as the superimposition and boolean operation of the mirrored elongation side on the normal side, was calculated, including the volumetric differences and the length of transversal and vertical asymmetry discrepancy. For more specific evaluation, both sides of the hemi-mandible were divided into the symphysis and parasymphysis (SP), mandibular body (MB), and mandibular angle (MA) regions. Other clinical variables include deviation of Me point, dental midline and molar relationship. The measurement of volumetric discrepancy between the two sides of post-surgical hemi-mandible were also calculated to verify the availability of virtual surgery. Paired t-tests were computed and the P value was set at .05. Results This study included 45 patients. The volume differences were 407.8±64.8 mm3, 2139.1±72.5 mm3, and 422.5±36.9 mm3; residual average transversal discrepancy, 1.9 mm, 1.0 mm, and 2.2 mm; average vertical discrepancy, 1.1 mm, 2.2 mm, and 2
Quantitative studies of incremental markings retained within human enamel have reconstructed the duration and rate (crown and cusp formation times, initiation and completion, daily enamel secretion rates) of permanent tooth development. This approach has provided one way of estimating human age-at-death, and facilitated comparative dental studies of primate evolution. Similar applications from deciduous enamel are inhibited because developmental reconstructions from incremental markings for these teeth are less frequently reported in the literature. This study quantified the duration and rate of enamel development for mesial (protoconid, metaconid) and distal cusps (hypoconid, entoconid) for first (dm1) and second (dm2) deciduous mandibular molars from an archaeological sample of modern human juveniles. Crown formation time can be calculated from the dm1 protoconid because growth initiates and completes in this cusp, and from the dm2 protoconid combined with the final period of hypoconid growth. The dm1 postnatal crown formation time included the time taken for the tubercle of Zuckerkandl to develop, and differed slightly compared to radiographic methods. The majority of dm1 protoconid cuspal (occlusal region) enamel formed before birth. The dm2 entoconid enamel formed mainly after birth. Birth reduced daily enamel secretion rates, changed the visibility of incremental markings, and disrupted enamel growth for 3 to 8 days. Findings presented here can contribute to age-at-death estimates for human infants aged 13-postnatal months or less, and should facilitate comparisons of primate deciduous incremental enamel development in an evolutionary context. Regression equations are included so that cuspal formation time can be estimated from enamel thickness. 2010 Wiley-Liss, Inc.
Noguchi, Akio; Balasingam, Vijayabalan; Shiokawa, Yoshiaki; McMenomey, Sean O; Delashaw, Johnny B
The anterior clinoid process (ACP), located on the skull base, is a relatively small structure, although its removal provides enormous gain in facilitating the management of lesions--either tumors or aneurysms--in the paraclinoid region and upper basilar artery. The extensive surgical field gained contributes to safer exposure of the neurovascular elements in the vicinity while avoiding excessive and hazardous retraction of the brain. In this report the authors present a technically simpler avenue for performing an extradural anterior clinoidectomy after reviewing the anatomy of the ACP and its anatomical variations. Additionally, the original Dolenc procedure and its subseqtient derivatives are compared and contrasted to the authors' simpler and less laborious technique. Different clinical situations in which to use the procedure are described based on the authors' experience from 60 cases (40 aneurysm cases and 20 tumor cases) during a 4-year period.
Rapaport, Benjamin H. J.; Heggie, Andrew A. C.
Simple bone cysts (SBCs) are benign lesions often found in the long bones of children between their first and second decades. They occasionally occur in the mandible but rarely in the mandibular condyle. A case of a 7-year-old female child with an increasing enlargement of the left mandibular condyle is presented. A 2 cm × 3 cm lytic lesion was explored and curetted through an intraoral vestibular incision and proved to be an SBC. Postoperative recovery was uncomplicated with remodeling of the condylar observed at 3 years follow-up.
Davidson, R M; Mohl, N D
The subject of pain is intimately related to that of mandibular function. It is now clear that certain types of temporomandibular disorders, particularly myofascial pain dysfunction, result, in part, from rhythmic muscle activity produced by parafunctional oral habits such as diurnal or nocturnal bruxism. Furthermore, in addition to phasic hyperactivity, evidence also suggests that masticatory muscles of patients with MPD are tonically hyperactive. The pain associated with such hyperactive musculature prompts many patients to seek professional help. This article provides an updated historical review of one important aspect of mandibular function and gives insight into the general "state of the art."
Yadav, Shishir; Nagabhushana, D; Rao, B Balaji; Mamatha, G P
An investigation study on sex identity through mandibular canine index directed to detect sexual dimorphism using the Mesio-Distal width of mandibular permanent canines and inter canine and inter canine arch width in the mandible was conducted in the Department of Oral Medicine and Radiology, Bapuji Dental College and Hospital, Davangere. 360 patients were subjected to the mesio-distal measurement and inter canine arch width. Males were detected correctly in 83.3% and in females 81%. They were statistically significant and the related literatures reviewed.
Hakim, Mumin; Burrier, Candice; Bhalla, Tarun; Raman, Vidya T; Martin, David P; Dairo, Olamide; Mayerson, Joel L; Tobias, Joseph D
Tumor progression during end-of-life care can lead to significant pain, which at times may be refractory to routine analgesic techniques. Although regional anesthesia is commonly used for postoperative pain care, there is limited experience with its use during home hospice care. We present a 24-year-old male with end-stage metastatic osteosarcoma who required anesthetic care for a right-sided above-the-elbow amputation. The anesthetic management was complicated by the presence of a large mediastinal mass, limited pulmonary reserve, and severe chronic pain with a high preoperative opioid requirement. Intraoperative anesthesia and postoperative pain management were provided by regional anesthesia using an interscalene catheter. He was discharged home with the interscalene catheter in place with a continuous local anesthetic infusion that allowed weaning of his chronic opioid medications and the provision of effective pain control. The perioperative applications of regional anesthesia in palliative and home hospice care are discussed. PMID:26442759
Hakim, Mumin; Burrier, Candice; Bhalla, Tarun; Raman, Vidya T; Martin, David P; Dairo, Olamide; Mayerson, Joel L; Tobias, Joseph D
Tumor progression during end-of-life care can lead to significant pain, which at times may be refractory to routine analgesic techniques. Although regional anesthesia is commonly used for postoperative pain care, there is limited experience with its use during home hospice care. We present a 24-year-old male with end-stage metastatic osteosarcoma who required anesthetic care for a right-sided above-the-elbow amputation. The anesthetic management was complicated by the presence of a large mediastinal mass, limited pulmonary reserve, and severe chronic pain with a high preoperative opioid requirement. Intraoperative anesthesia and postoperative pain management were provided by regional anesthesia using an interscalene catheter. He was discharged home with the interscalene catheter in place with a continuous local anesthetic infusion that allowed weaning of his chronic opioid medications and the provision of effective pain control. The perioperative applications of regional anesthesia in palliative and home hospice care are discussed.
Cruciate ligament injury - anterior; ACL injury; Knee injury - anterior cruciate ligament (ACL) ... knee. It prevents the knee from bending out. Anterior cruciate ligament (ACL) is in the middle of the knee. ...
... Week of Healthy Breakfasts Shyness Anterior Cruciate Ligament (ACL) Injuries KidsHealth > For Teens > Anterior Cruciate Ligament (ACL) ... and Recovery Coping With an ACL Injury About ACL Injuries A torn anterior cruciate ligament (ACL) is ...
Yoshioka, Izumi; Igawa, Kaori; Nagata, Jyunko; Yoshida, Maho; Baba, Takashi; Ichiki, Takeshi; Kondoh, Yudai; Takamori, Koichi; Kashima, Koji; Sakoda, Sumio
The aim of this retrospective study was to evaluate the risk factors associated with breakage of biodegradable plate systems after bilateral sagittal split mandibular setback. We studied 169 Japanese adults (62 men, 107 women; age range 16-53 years) with deformities of the jaw diagnosed as mandibular prognathism. All patients were treated by bilateral sagittal split osteotomy (BSSO) with 2 biodegradable fixation plates and screws at the anterior mandibular ramus. We collected the following data from the medical records and radiological findings: sex; age; degree of setback; presence of asymmetry; presence of open bite; operation; design of the plate; operating time; and blood loss. Multiple logistic regression analysis was used to find the factors that were independently associated with the dependent variable: breakage of the biodegradable plate system. In 10 of the 169 patients (6%) the biodegradable plate system for the BSSO broke. Factors that influenced whether or not the biodegradable plate system fractured were if they were asymmetrical (odds ratio (OR) 5.35; P=0.02) and had an open bite (OR 5.20; P=0.02). Asymmetry or open bite was significantly associated with breaks in the biodegradable plate system. Biodegradable plates should be used only when loading is minimal.
Yousef, Mohammed K
The majority of dental trauma involves anterior teeth, especially the maxillary central incisors. A mandibular incisor fracture with or without pulp tissue involvement is considerably less common. Different approaches for treating these fractured teeth have been reported in the literature. The type of treatment rendered depends mainly on the extent of fracture, pulp involvement, radicular fracture, biologic width infringement or violation, and presence of the fractured piece. This case report illustrates reattachment of fractured fragments on two mandibular incisors without pulp exposure using a new proposed reattachment method using a combination of two different types of composite materials together with an orthodontic lingual retention wire. An 8-year-old female patient presented with fractured mandibular left incisors (Ellis class II fracture). Broken pieces were saved and brought in a closed container in water. Periapical radiographs revealed no evidence of pulpal involvement in either tooth and no periapical radiolucency was noticed. Fractured fragments and the broken teeth were prepared with circumferential bevels. Reattachment of the fractured fragments were done using two types of composite resin materials and a lingual orthodontic retention wire was also used. The patient was recalled after 8 months to follow up both teeth. Clinical examination revealed excellent composite restorations covering the fracture lines. PMID:25897267
Coelho, Mariana Freire; Cavalcanti, Bruno das Neves; Claro Neves, Ana Christina; Jóias, Renata Pilli; Rode, Sigmar de Mello
Varying the inclination of the dental chair backrest might alter the distribution of occlusal contact points. The purpose of this study was to identify the influence of backrest inclination on the registration of the mandibular position. Ten participants aged between 18 and 30 years with a complete permanent dentition, uncompromised motor function, no tooth mobility, and no temporomandibular disorders were selected. To register interocclusal contacts, an autopolymerizing methylmethacrylate device was adapted to the maxillary anterior teeth and a composite resin increment was added to the mandibular central incisors. Contacts were registered with the following variations in the inclination of the dental chair backrest: 90 degrees, 120 degrees, and 180 degrees. A standardized digital photograph was made of each mark in each backrest position, and the images were superimposed to measure the distances in registration from 90 to 120 and from 90 to 180 degrees. Data were analyzed with the Student paired t test (α=.05). When the chair was inclined from the 90-degree to the 120-degree position, the mandible was repositioned posteriorly by a mean of 0.67 mm, but the difference was not statistically significant. When the chair was inclined from the 90-degree to the 180-degree position, however, the mandible was repositioned posteriorly by a statistically significant mean of 1.41 mm. Mandibular position is influenced by increasing inclination, and this influence was statistically significant at a 180-degree incline. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Nakajima, J; Hideshima, M; Takahashi, M; Taniguchi, H; Ohyama, T
This study aimed to investigate the effects of different sensory-evaluated food textures on masticatory movements, and to identify meaningful factors that correspond to different food textures. Masticatory movements of three healthy subjects were evaluated with a jaw movement tracking device using five different test foods: almond, hard and light rice crackers, apple, and chewing gum. The movements of the incisor point, working and non-working condyle and the entire mandible at the occlusal phase in the horizontal plane were analyzed. For harder foods, the incisor entered the intercuspal position from a rear and lateral, the working condyle showed anterior and noticeable medial movements as the entire mandible translated posteriorly and medially. For soft foods, the incisor movements were nearly coincidental with the lateral border movements, and the mandible rotated towards the inner side near the working condyle. Although the overall paths of the mandibular movements are individually different, it appeared that jaw movement at the final closure is particular to the food texture. From the standpoint of mandibular movements, it is suggested that masticatory movements during the occlusal phase in the horizontal plane is useful for revealing the relationship between mandibular movements and food textures that were evaluated with onomatopoetic words.
Miliam, Palle B; Basse, Peter N
Anterior tarsal tunnel syndrome is a rare entrapment neuropathy of the deep peroneal nerve beneath the extensor retinaculum of the ankle. It may be rare because it is underrecognized clinically.We present a case regarding a 29-year-old man, drummer, who for one and a half year experienced clinical symptoms of anterior tarsal tunnel syndrome. A surgical decompression of the anterior tarsal tunnel was performed, and at the check three months later the symptoms where gone. One year after, there were still no symptoms.
Monteagudo, B; Cabanillas, M; de las Heras, C; Cacharrón, J M
Anterior cervical hypertrichosis was described by Trattner and coworkers in 1991. It consists of a
Monini, André da Costa; Júnior, Luiz Gonzaga Gandini; Maia, Luiz Guilherme Martins; Pinto, Ary dos Santos
This study evaluated posteroanterior cephalograms before and after treatment and long term follow-up of Class II division 1 patients treated with bionator. The objective was to demonstrate the transverse growth of maxilla and mandible during and after bionator therapy. Measurement of transverse dimensions between posterior maxillary and mandibular implants, as well as the distances between the buccal, gonial and antegonial points were recorded. Measurements were analyzed at three periods: T1 - before bionator therapy, T2 - after bionator therapy and T3 - 5.74 years after T2. There was statistically significant transverse increase due to growth and/or treatment for all variables, except for the distance between the anterior maxillary implants. During the study period only the anterior maxillary area did not show transverse growth.
Hegde, S; Kumar, B R
Two rare cases of talon cusps in the mandibular incisors were observed during a prevalence study on talon cusp. One of them was seen on a mandibular primary lateral incisor. The other one was observed on the mandibular left permanent central incisor, and the right mandibular permanent central incisor was congenitally missing. There were no associated developmental syndromes with either of the cases reported. Of the 4770 children examined, nine cases had talon cusp with only two rare cases of mandibular talon cusp, one in the primary dentition and the other in the permanent dentition.
Cooper, L F; Scurria, M S; Lang, L A; Guckes, A D; Moriarty, J D; Felton, D A
The goal of this study was to provide evidence to support simplified treatment of mandibular edentulism using denture fabrication and implant placement to circumvent the need for second-stage surgeries or prosthodontic superstructures. A 5-year prospective clinical trial is reported, which involved treatment of mandibular edentulism using the single-stage surgical placement of a TiOblast microthreaded titanium screw implant with immediate replacement of a relieved mandibular overdenture and eventual retention of the overdenture with reduced ball abutments. Fifty-eight patients were treated; 116 implants were placed using a single-stage surgical approach, with a duplicate mandibular denture as the tomographic/surgical template. Mandibular dentures were relieved and relined with a tissue conditioning material and placed immediately after implant surgery. After 3 months, Conical Seal Design ball abutments were placed and attachments were secured in the overdentures by heat-polymerizing laboratory reline methods. Five of the 116 consecutively placed implants failed at 2 to 4 months, providing an immediate implant survival rate of 95.69% at the time of attachment connection. Pain and inflammation were not common to all failures, and infection was not reported in any of the 5 failures. The immediate placement of implants by a single-stage surgical procedure in the parasymphyseal region of the mandible, followed by placement of a relined mandibular denture, results in predictable and asymptomatic healing of implants that display the clinical and radiographic features of osseointegration. Encouraging results at the immediate observation period (attachment connection) must be tempered by the need for prudent and detailed clinical and radiologic evaluation over the 5-year trial period.
Backround Functional and cosmetic defects in the maxillofacial region are caused by various ailments and these defects are addressed according to their need. Simplicity of procedure, intact facial function and esthetic outcome with the least possible donor site morbidity are the minimum requirements of a good reconstruction. Oro-mandibular reconstruction, although a challenge for the head and neck reconstructive surgeon, is now reliable and highly successful with excellent long-term functional and aesthetic outcomes with the use of autogenous bone grafts. Reconstruction of trauma- or mandibular oncologic defects with bony free flaps is considered the gold standard. However the the optimal reconstruction of mandibular defects is still controversial in regards to reconstructive options which include the donor site selection and the timing of surgery. The purpose of this study was to determine the outcome of different osseous reconstruction options using autogenous bone grafts for mandibular reconstructions. Methods This study was carried out on 178 patients with mandibular bone defects. They were reconstructed with autogenous bone grafts from different donor sites. At post operative visits they were evaluated for functional and cosmetic results. Results The success rate found in this study was around 90%. Only 7.6% of the cases showed poor results regarding facial contours and mouth opening. All other patients were satisfied with their cosmesis and mouth opening at the recipient sites was in the normal range during last follow-up visits. Donor sites were primarily closed in all cases and there was no hypertrophic scar. Conclusion Based on this study, autogenous bone grafts are a reliable treatment modality for the reconstruction of mandibular bone defects with predictable aesthetic and functional outcomes. As the free vascularized fibular flap has the least resorption and failure rate, it should be the first choice for most cases of mandiblular reconstruction. PMID
Soleymani, Ali; Namaryan, Nafiseh; Moudi, Ehsan; Gholinia, Ali
Introduction: The present study was conducted to assess the morphology of mandibular canines using cone-beam computed tomography (CBCT) in a north Iranian population. Methods and Materials: For the morphological assessment of mandibular canines, 150 CBCT images taken from patients for different reasons were used. The mandibular canines were examined in sagittal, coronal and axial dimensions. The canal pattern, number of roots/canals, the tooth length, the orientation of the roots and the position of the apical foramina were evaluated and the effect of gender on each variable was assessed. The obtained data were analyzed using the Chi-square and student’s t-tests. Results: According to the Vertucci’s criteria, the most common pattern was type I morphology (89.7%), followed by types III (5.7%), II (3.7%) and V (1%). No significant differences were observed between the male and female patients in terms of canal type (P>0.05). Gender difference is a factor which affected the root length and the number of mandibular canine root and root canal. There were 296 single-root and four double-root canines. The double-root canines and mandibular canine with two canals were significantly more common among men than women (P=0.00). The apical foramen was laterally positioned in 68.3% and centrally in 31.7% of the cases, and the root curvatures were mostly oriented toward the buccal region. No significant statistical difference was observed for mentioned parameters in right and left half of the jaw. Conclusion: Due the diverse morphology and the potential presence of a second mandibular canine among Iranians, dentists should perform endodontic treatments with greater care. CBCT is an accurate tool for the morphological assessment of root canals. PMID:28179930
Uvais, N. A.; Sreeraj, V. S.; Sathish Kumar, S. V.
Specific serotonin reuptake inhibitors have been associated with the occurrence of drug-induced parkinsonism, dystonia, dyskinesia, and akathisia. Here, we describe a young female patient with a diagnosis of the moderate depressive episode who developed mandibular dystonia and bruxism with sertraline in the absence of concurrent prescription of medications, which have potential action on the dopaminergic system. PMID:28349014
Kaban, Leonard B
This paper represents more than 30 years of discussion and collaboration with Drs Joseph Murray and John Mulliken in an attempt to understand growth patterns over time (ie, fourth dimension) in patients with hemifacial microsomia (HFM). This is essential for the development of rational treatment protocols for children and adults with jaw asymmetry. Traditionally, HFM was thought of as a unilateral deformity, but it was recognized that 20% to 30% of patients had bilateral abnormalities. However, early descriptions of skeletal correction addressed almost exclusively lengthening of the short (affected) side of the face. Based on longitudinal clinical observations of unoperated HFM patients, we hypothesized that abnormal mandibular growth is the earliest skeletal manifestation and that restricted growth of the mandible plays a pivotal role in progressive distortion of both the ipsilateral and contralateral facial skeleton. This hypothesis explains the progressive nature of the asymmetry in patients with HFM and provides the rationale for surgical lengthening of the mandible in children to prevent end-stage deformity. During the past 30 years, we have learned that this phenomenon of progressive distortion of the adjacent and contralateral facial skeleton occurs with other asymmetric mandibular undergrowth (tumor resection, radiation therapy, or posttraumatic defects) and overgrowth (mandibular condylar hyperplasia) conditions. In this paper, I describe the progression of deformity with time in patients with mandibular asymmetry as a result of undergrowth and overgrowth. Understanding these concepts is critical for the development of rational treatment protocols for adults with end-stage asymmetry and for children to minimize secondary deformity.
Pirttiniemi, Pertti; Peltomäki, Timo; Müller, Lukas; Luder, Hans U
Deviations in the growth of the mandibular condyle can affect both the functional occlusion and the aesthetic appearance of the face. The reasons for these growth deviations are numerous and often entail complex sequences of malfunction at the cellular level. The aim of this review is to summarize recent progress in the understanding of pathological alterations occurring during childhood and adolescence that affect the temporomandibular joint (TMJ) and, hence, result in disorders of mandibular growth. Pathological conditions taken into account are subdivided into (1) congenital malformations with associated growth disorders, (2) primary growth disorders, and (3) acquired diseases or trauma with associated growth disorders. Among the congenital malformations, hemifacial microsomia (HFM) appears to be the principal syndrome entailing severe growth disturbances, whereas growth abnormalities occurring in conjunction with other craniofacial dysplasias seem far less prominent than could be anticipated based on their often disfiguring nature. Hemimandibular hyperplasia and elongation undoubtedly constitute the most obscure conditions that are associated with prominent, often unilateral, abnormalities of condylar, and mandibular growth. Finally, disturbances of mandibular growth as a result of juvenile idiopathic arthritis (JIA) and condylar fractures seem to be direct consequences of inflammatory and/or mechanical damage to the condylar cartilage.
Ma, Zhigui; Yang, Chi; Zhang, Shanyong; Xie, Qianyang; Shen, Yuqing; Shen, Pei
Objective: To introduce and evaluate a novel approach in treating horizontally impacted mandibular second and third molars. Materials and methods: An orthodontic technique was applied for treatment of horizontally impacted mandibular second and third molars, which included a push-type spring for rotation first, and then a cantilever for extrusion. There were 8 mandibular third molars (M3s) and 2 second molars (M2s) in this study. Tooth mobility, extraction time, the inclination and parallelism of the impacted tooth, alveolar bone height of the adjacent tooth, and the relationship of impacted M3 and the inferior alveolar nerve (IAN) were evaluated. Results: Two horizontally impacted M2s could be upright in the arch and good occlusal relationships were obtained after treatment. All impacted M3s were successfully separated from the IAN, without any neurologic consequences. The average extraction time was 5 minutes. There was a significant change in the inclination and parallelism of the impacted tooth after treatment. A new bone apposition with the average height of 3.2 mm was noted distal to the adjacent tooth. Conclusions: This two-step orthodontic technique as presented here may be a safe and feasible alternative in management of severely horizontally impacted mandibular molars, which achieves a successful separation of M3s from the IAN and an excellent position for M2s. PMID:25419364
Sforza, Chiarella; Ugolini, Alessandro; Sozzi, Davide; Galante, Domenico; Mapelli, Andrea; Bozzetti, Alberto
To detect the changes in 3D mandibular motion after two types of condylar fracture therapies. Using a 3D motion analyzer, free mandibular border movements were recorded in 21 patients successfully treated for unilateral fractures of the mandibular condylar process (nine patients: open reduction, rigid internal fixation, and functional treatment; 12 patients: closed reduction and functional treatment; follow-up: 6-66 months), and in 25 control subjects. No differences were found among the groups at maximum mouth opening (MO), protrusion and in lateral excursions. During opening, the patients had a larger maximal deviation to the fractured side than the controls (controls 2.3 mm, open treatment 3.9 mm, closed treatment 4.2 mm; Kruskal-Wallis test, p=0.014; closed treatment vs. controls, p=0.004), with a larger coronal plane angle (controls 2.4°, open treatment 3.6°, closed treatment 4.4°; p=0.016; closed treatment vs. controls, p=0.013). In the closed treatment patients, a longer follow-up was related to increased maximum MO (p=0.04), sagittal plane angle (p=0.03), and reduced lateral mandibular deviation during MO (p=0.03). Mandibular condylar fractures can recover good function; some kinematic variables of mandibular motion were more similar to the norm in the open treatment patients than in closed treatment patients. Copyright © 2010 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
ELsyad, Moustafa Abdou; Agha, Nora Nory; Habib, Ahmed Ali
The aim of this study was to evaluate and compare the retention and stability of mandibular implant overdentures using different types of resilient attachments. Two implant analogs were inserted in the canine areas of an acrylic edentulous mandibular model. A metal-reinforced experimental overdenture was constructed and connected to the implant analogs (on two occasions) using either resilient telescopic or Locator attachments. Locators were divided into three subgroups according to the degree of retention of the male nylon insert: Locator extra-light retention (blue insert), Locator light retention (pink insert), and Locator medium retention (transparent insert). Vertical and oblique (anterior, posterior, and lateral) dislodging forces were measured at the beginning of the study (initial retention) and after 540 cycles of denture insertion and removal (final retention). For all dislodging forces, Locator medium recorded the highest initial and final retention. Telescopic attachments recorded the lowest retention during vertical and anterior dislodging, and Locator extra-light recorded the lowest retention during lateral and posterior dislodging. For all types of Locator attachments, anterior dislodging recorded the highest initial and final retention, and lateral dislodging recorded the lowest retention. For the telescopic attachment, posterior dislodgment recorded the highest initial and final retention, and anterior dislodging recorded the lowest retention. After repeated denture insertions and removals, the highest retention and stability were recorded with Locator medium followed by Locator light. The lowest retention was recorded with resilient telescopic attachment, and the lowest stability was recorded with Locator extra-light.
Sabet, Marwa E; El-Korashy, Dalia I; El-Mahrouky, Nesrin A
The aim of this study was to assess the effect of platform switching, using 3 different abutment sizes on the strain developed around implants supporting mandibular overdenture, using strain gages. An implant-supported overdenture was constructed on an acrylic model with 2 implant fixtures placed at canine areas. Abutments of different sizes (5.5 mm, 4.5 mm, and 3.5 mm diameter) were screwed in the implant fixtures (platform switching). Anterior axial, anterior off-axis (lateral), and posterior load were applied on each abutment through a load applicator attached to the upper compartment of a universal testing machine until a load of 100 N, at which instant, the resultant strain on the implants was recorded using 4 strain gages connected to a 4-channel strain indicator. Data were analyzed by 1-way ANOVA at a significance level of 0.05, followed by Tukey-Kramer multiple comparisons test. Anterior axial load application and decreasing the abutment size lead to a decrease in the strain developed on the loaded abutment and to an increase in the strain developed on the unloaded abutment. Anterior off-axis load application and decreasing the abutment size lead to an increase in the strain developed on the loaded abutment and to a decrease on the unloaded abutment. On the other hand, posterior load application and decreasing the abutment size lead to an increase in the strain developed on the mesial side of the near abutment and a decrease in the strain developed on its distal side, where there was a significant increase in the strain developed on the mesial and distal sides of the far abutment. The distribution of the strain developed because of decreasing the abutment size does not favor the use of platform switching in an implant-supported mandibular overdenture.
Rychel, Amanda L.; Swalla, Billie J.
Ptychodera flava is a hemichordate whose anterior structures regenerate reproducibly from posterior trunk pieces when amputated. We characterized the cellular processes of anterior regeneration with respect to programmed cell death and cell proliferation, following wound healing. We found scattered proliferating cells at day two of regeneration using a PCNA antibody. On day four, most proliferating cells were associated with the nerve tract under the epidermis, and on day six, a small proboscis derived from proliferated cells was regenerated, and a mouth had broken though the epidermis. TUNEL detected elevated levels of apoptosis in the endoderm that began furthest away from the region of wound healing, then moved anteriorly over eight days. Posterior to anterior apoptosis is likely to remove digestive endoderm for later differentiation of pharyngeal endoderm. We hypothesize that P. flava regeneration is nerve dependent and that remodeling in the gut endoderm plays an important role in regeneration. PMID:18924231
Tucunduva, Rosana Mara Adami; Imada, Thaís Sumie Nozu; Lopes, Ivna Albano; Rubira-Bullen, Izabel Regina Fischer; de Carvalho, Izabel Maria Marchi
The Pierre Robin sequence (PRS) and the Treacher Collins syndrome (TCS) are conditions that cause significant abnormalities of jaw. This study was conducted in anticipation of evaluating the morphology of interforaminal region and identify the anatomic variations: anterior loop and mandibular incisive canal, in individuals with PRS and TCS by cone-beam computed tomography and compare them with individuals without craniofacial anomalies. By applying the t-test, the results showed no statistically significant difference, allowing to infer that there are no significant differences in interforaminal mandible morphology between groups and indicated that the prevalence and location of the studied anatomic variations are consistent with those described in literature.
Scheffler, Nicole R.; Proffit, William R.; Phillips, Ceib
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
Glenn, Andrea L.; Yang, Yaling; Raine, Adrian; Colletti, Patrick
Functional imaging studies of psychopathy have demonstrated reduced activity in the anterior cingulate, yet it is unclear whether this region is structurally impaired. In this study, we used structural MRI to examine whether volumetric differences exist in the anterior cingulate between psychopathic (n=24) and control (n=24) male participants. We found no group differences in the volume of the anterior cingulate or its dorsal and ventral subregions. Our findings call into question whether the anterior cingulate is impaired in psychopathy, or whether previous findings of reduced activity may result from reduced input from other deficient regions. PMID:20630717
Kreczi, Amelia; Proff, Peter; Reicheneder, Claudia; Faltermeier, Andreas
This study was performed to examine craniofacial structures in persons with hypodontia and to reveal any differences, that may occur, when agenetic teeth are only found in the maxilla, the mandible or in both jaws. The groups consistent of 50 children (33 girls, 17 boys) aged between 9 and 13.5 years were analyzed and assigned to three subgroups. Group 1 = upper jaw hypodontia. Group 2 = lower jaw hypodontia. Group 3 = hypodontia in both jaws. Eleven angular and three index measurements from lateral encephalographs and two linear measurements from dental blaster casts were calculated. All data was statistically analyzed, parameters with p < 5% were investigated for each subgroup respectively. In comparison with standards the study group showed bimaxillary retrognathism and a reduction of the lower anterior facial height. Moreover both overbite and overjet significantly increased. Other values laid within the normal ranges. Evaluating results of the subgroups, differences in the means of SNA, SNB and overjet between the groups were observed.Analysis of the mandibular growth pattern revealed, that neither vertical nor horizontal patterns are dominant in hypodontia patients. In certain dentofacial parameters differences between persons with hypodontia and such with full dentition exist. According to our findings agenetic teeth may have a negative influence on the saggital development of a jaw and the lower face and may be responsible for increased overbites. This should receive attention in orthodontic treatment of hypodontia patients. © 2011 Kreczi et al; licensee BioMed Central Ltd.
Deyhimi, Parviz; Darisavi, Soheila; Khalesi, Saeideh
Stafne bone cavities (SBCs) are uncommon well-demarcated defects of the mandible, which often occur in the posterior portion of the jaw bone and are usually asymptomatic. Furthermore, SBC is found in men aged 50–70-year-old. Anterior mandibular variants of SBC are very rare. This article describes a case of anterior SBC in a 45-year-old man that resembled endodontic periapical lesions. Upon histopathological examination, it turned out to be a normal salivary gland tissue. PMID:27857772
Lewis, S. J.; Whalen, E. J.; Beltz, T. G.; Johnson, A. K.
This study examined whether a prior electrolytic lesion of the tissue surrounding the anteroventral third ventricle (AV3V) would affect the increase in mean arterial blood pressure (MAP) and the fall in heart rate (HR) produced by systemic injection of the nitric oxide synthesis (NOS) inhibitor, NG-nitro-L-arginine methyl ester (L-NAME; 25 micromol/kg, i.v.) in conscious rats. L-NAME produced a smaller increase in MAP in AV3V-lesion than in sham-lesion rats (+19+/-3 vs. +40+/-3 mmHg, respectively; P<0.05). In contrast, L-NAME produced similar falls in HR in the AV3V-lesion and sham-lesion rats (-103+/-15 vs. -97+/-8 bpm, respectively; P<0.05). These findings demonstrate that the L-NAME-induced pressor response is dependent upon the integrity of the AV3V region, whereas the L-NAME-induced bradycardia is not. Copyright 1999 Elsevier Science B. V.
Lewis, S. J.; Whalen, E. J.; Beltz, T. G.; Johnson, A. K.
This study examined whether a prior electrolytic lesion of the tissue surrounding the anteroventral third ventricle (AV3V) would affect the increase in mean arterial blood pressure (MAP) and the fall in heart rate (HR) produced by systemic injection of the nitric oxide synthesis (NOS) inhibitor, NG-nitro-L-arginine methyl ester (L-NAME; 25 micromol/kg, i.v.) in conscious rats. L-NAME produced a smaller increase in MAP in AV3V-lesion than in sham-lesion rats (+19+/-3 vs. +40+/-3 mmHg, respectively; P<0.05). In contrast, L-NAME produced similar falls in HR in the AV3V-lesion and sham-lesion rats (-103+/-15 vs. -97+/-8 bpm, respectively; P<0.05). These findings demonstrate that the L-NAME-induced pressor response is dependent upon the integrity of the AV3V region, whereas the L-NAME-induced bradycardia is not. Copyright 1999 Elsevier Science B. V.
Piassi, Eluza; Antunes, Leonardo Santos; Andrade, Marcia Rejane Thomas Canabarro
Anterior crossbite (AC) refers to a condition in which the maxillary anterior teeth are placed lingually in their relationship with the mandibular anterior teeth. This dental condition results in visible incisor differences that are associated with higher levels of dissatisfaction with appearance and have potential to negatively impact on oral health-related quality of life (OHRQoL) of the children. The aim of this paper was to report two cases of interceptive orthodontic treatment of twin children with anterior crossbite and its impact on OHRQoL of these children. Although AC affects negatively psychosocial aspects of OHRQoL of the children, the interceptive orthodontic treatment of children with AC was essential to improve their OHRQoL. PMID:27738533
Narcisi, E M
A new glass-ceramic material, IPS Empress 2, is revolutionizing esthetic restorative dentistry by allowing metal-free, three-unit bridge construction in anterior and premolar single-pontic areas. The case discussed in this article illustrates the material's application in the dual-arch restoration of a young woman with congenitally missing teeth. The material was used as an alternative to single-tooth implant restorations to place two maxillary three-unit bridges, one mandibular three-unit bridge, and two mandibular porcelain veneers. IPS Empress 2 provides an esthetic alternative to porcelain-fused-to-metal restorations by facilitating attractive, functional tooth restoration.
Tabrizi, Reza; Shahidi, Shoaleh; Bahramnejad, Emad; Arabion, Hamidreza
Statement of the Problem: In orthognathic surgeries, proper condylar position is one of the most important factors in postoperative stability. Knowing the condylar movement after orthognathic surgery can help preventing postoperative instabilities. Purpose: The aim of this study was to evaluate the condylar positional changes after Le Fort I maxillary superior repositioning along with mandibular advancement by using cone beam computed tomography (CBCT). Materials and Method: This cross-sectional study was conducted on 22 subjects who had class II skeletal malocclusion along with vertical maxillary excess. Subjects underwent maxillary superior repositioning (Le Fort I osteotomy) along with mandibular advancement. The CBCT images were taken a couple of days before the surgery (T0), and one month (T1) and 9 months (T2) after the surgery. The condyles positions were determined from the most superior point of the condyle to three distances including the deepest point of the glenoid fossa, the most anterior-inferior point of the articular eminence, and the most superior point of the external auditory meatus in the sagittal plane. Results: The mean mandibular advancement was 4.33±2.1 mm and the mean maxillary superior repositioning was 4.66±0.3 mm. The condyles displaced inferiorly, anteriorly, and laterally between T0 and T1. They were repositioned approximately in the initial position in T2. No correlation was observed between the mandibular and maxillary movement and the condylar positions. Conclusion: The condyles displaced in the inferior-anterior-lateral position one month after the bilateral sagittal split osteotomy for mandibular advancement in combination with the maxillary Le Fort I superior repositioning. It seems that the condyles adapted approximately in their initial position nine months after the surgeries. PMID:27942547
Nemati, Somayeh; Ashouri Moghadam, Anahita; Dalili Kajan, Zahra; Mohtavipour, Seyedeh Tahereh; Amouzad, Hasan
Statement of the Problem Insufficient information about the anatomical positions and structure of mandibular canal provokes unwanted damage to this important structure of mandible. Purpose The aim of this study was to determine the visibility and anatomical variations of mandibular canal in digital panoramic radiographs of dentulous and edentulous patients in a sample of Iranian population. Materials and Method In this retrospective-analytical research, 249 digital panoramic radiographs in dentulous group and 126 in edentulous group were studied by an expert oral and maxillofacial radiologist. In both groups, the visibility of canal borders in anterior, middle, and posterior areas were examined. In dentulous group, the distance between the canal and apex of the first and second molars were measured. Canal-to-alveolar crest distance and lower mandibular border was measured in three different points for both groups. Finally, the upper-lower positions of canals were determined. Results In both groups, most visibility occurred in 1/3 of posterior and the least visibility was detected in 1/3 of anterior, with the intermediate being the most visible part (Type 2). There was no significant difference between the left and right sides in all cases. In dentulous group, no correlation was found between the visibility, age, and gender (p> 0.05); however, canal position was related to gender (p= 0.03 and p= 0.04 in right and left sides, respectively). High position was more frequent in females and intermediate position was more common in males. In edentulous group, no correlation was found between age, gender, and canal position (p> 0.05). Conclusion The most visibility of mandibular canal was in its third posterior and the least was in its third anterior part. Although the middle position of canal was more frequently visible than the high position in this study, it does not refute the possibility of damaging the mandibular canal in critical surgeries. PMID:27284556
Horiba, Kazuki; Muramatsu, Chisako; Hayashi, Tatsuro; Fukui, Tatsumasa; Hara, Takeshi; Katsumata, Akitoshi; Fujita, Hiroshi
Findings on dental panoramic radiographs (DPRs) have shown that mandibular cortical index (MCI) based on the morphology of mandibular inferior cortex was significantly correlated with osteoporosis. MCI on DPRs can be categorized into one of three groups and has the high potential for identifying patients with osteoporosis. However, most DPRs are used only for diagnosing dental conditions by dentists in their routine clinical work. Moreover, MCI is not generally quantified but assessed subjectively. In this study, we investigated a computer-aided diagnosis (CAD) system that automatically classifies mandibular cortical bone for detection of osteoporotic patients at early stage. First, an inferior border of mandibular bone was detected by use of an active contour method. Second, regions of interest including the cortical bone are extracted and analyzed for its thickness and roughness. Finally, support vector machine (SVM) differentiate cases into three MCI categories by features including the thickness and roughness. Ninety eight DPRs were used to evaluate our proposed scheme. The number of cases classified to Class I, II, and III by a dental radiologist are 56, 25 and 17 cases, respectively. Experimental result based on the leave-one-out cross-validation evaluation showed that the sensitivities for the classes I, II, and III were 94.6%, 57.7% and 94.1%, respectively. Distribution of the groups in the feature space indicates a possibility of MCI quantification by the proposed method. Therefore, our scheme has a potential in identifying osteoporotic patients at an early stage.
Wang, Tongyue; Han, Jeong Joon; Oh, Hee-Kyun; Park, Hong-Ju; Jung, Seunggon; Park, Yeong-Joon; Kook, Min-Suk
This study aimed to identify risk factors associated with bad splits during sagittal split ramus osteotomy by using three-dimensional computed tomography. This study included 8 bad splits and 47 normal patients without bad splits. Mandibular anatomic parameters related to osteotomy line were measured. These included anteroposterior width of the ramus at level of lingula, distance between external oblique ridge and lingula, distance between sigmoid notch and inferior border of mandible, mandibular angle, distance between inferior outer surface of mandibular canal and inferior border of mandible under distal root of second molar (MCEM), buccolingual thickness of the ramus at level of lingula, and buccolingual thickness of the area just distal to first molar (BTM1) and second molar (BTM2). The incidence of bad splits in 625 sagittal split osteotomies was 1.28%. Compared with normal group, bad split group exhibited significantly thinner BTM2 and shorter sigmoid notch and inferior border of mandible (P <0.05). However, for BTM1 and buccolingual thickness of the ramus at level of lingula, there was no statistical difference between the 2 groups. Mandibular angle, anteroposterior width of the ramus at level of lingula, external oblique ridge and lingula, and MCEM were not significantly different between the groups. This study suggests that patients with shorter ramus and low thickness of the buccolingual alveolar region distal to the second molar had a higher risk of bad splits. These anatomic data may help surgeons to choose the safest surgical techniques and best osteotomy sites.
Suda, Daisuke; Ohazama, Atsushi; Maeda, Takeyasu; Kobayashi, Tadaharu
Mandibular distraction surgery is a critical treatment for jaw deformity. However, abnormal mandibular condylar bone resorption is often seen as complication after surgery. Our previous study using a rat mandibular distraction model suggested that overloading leads to mandibular condylar resorption. Host factors are also believed to influence the resorption. To understand the relationship between host factors and resorption, we investigated the effect of changing bone mass and architecture on the mandibular condyle using FK506. FK506, an immunosuppressant, was used to compromise bone mass and architecture in this study. Animals were divided into 4 groups: distraction surgery (Dist), FK506 administration (FK), distraction surgery with FK506 administration (FK + Dist), and no surgery or FK506 administration (Cont). The FK group showed reduced bone mass and impaired bone architecture. The Dist group exhibited abnormal bone resorption on the surface of the condyles, which was slightly exacerbated in the FK + Dist group. Bone defect length decreased over time as a result of bone apposition in the Dist group. However, in the FK + Dist group, the bone defect length remained the same. These results suggest that bone mass and architecture strongly affect the tolerance to the overloading and adaptation with bone apposition in condylar resorption site. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Gao, Quan-Wen; Song, Hui-Feng; Xu, Ming-Huo; Liu, Chun-Ming; Chai, Jia-Ke
To explore the clinical application of mandibular-driven simultaneous maxillo-mandihular distraction to correct hemifacial microsomia with rapid prototyping technology. The patient' s skull resin model was manufactured with rapid prototyping technology. The osteotomy was designed on skull resin model. According to the preoperative design, the patients underwent Le Fort I osteotomy and mandibular ramus osteotomy. The internal mandible distractor was embedded onto the osteotomy position. The occlusal titanium pin was implanted. Distraction were carried out by mandibular-driven simultaneous maxillo-mandihular distraction 5 days after operation. The distraction in five patients was complete as designed. No infection and dysosteogenesis happened. The longest distance of distraction was 28 mm, and the shortest distance was 16 mm. The facial asymmetry deformity was significantly improved at the end of distraction. The ocelusal plane of patients obviously improved. Rapid prototyping technology is helpful to design precisely osteotomy before operation. Mandibular-driven simultaneous maxillo-mandibular distraction can correct hemifacial microsomia. It is worth to clinical application.
Ferrario, V F; Sforza, C; Miani, A; Tartaglia, G
Euclidean-distance matrix analysis (EDMA) was used to analyse the dental arch form in 50 men and 45 women aged 20-27 yr with sound dentitions. Fourteen landmarks, corresponding to the centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar), were identified on the dental casts of subjects. All the possible linear distances between pairs of teeth were computed and maxillary/mandibular arch differences within sex were tested by EDMA. In both sexes, the maxillary arch was larger than the mandibular arch; arch shape was also significantly different. All teeth contributed to the shape difference between arches regardless of gender. EDMA also separated the influence of anterior and posterior teeth in the determination of upper/lower arch characteristics.
Roy, Abhishek Singha; Singh, Gulshan Kr; Tandon, Pradeep; Chaudhary, Ramsukh
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.
Esan, Temitope; Schepartz, Lynne A
Background Third molar influence on anterior crowding is controversial, but they are assumed to play a major role in compromising dental arch space. Aim To evaluate the relationship among impaction, agenesis and crowding in black South African males. Subjects and method Mandibles and maxillae of 535 black South African males in the Raymond A. Dart Collection of Human Skeletons, University of the Witwatersrand were examined for anterior crowding and third molar agenesis and impaction. Dental crowding was determined using Little's irregularity index. Results Individuals with impaction showed more moderate-to-extreme crowding than those with agenesis. Bilateral third molar presence was more frequently associated with ideal-to-minimal crowding. Weak positive but significant correlations between crowding and impaction were found (mandible, ρ = 0.154, p = 0.000; maxilla ρ = 0.130, p = 0.000). The direction was the opposite for bilateral presence of molars (mandible, ρ = -0.135, p = 0.02; maxilla, ρ = -0.111, p = 0.010). Odds of mandibular crowding were greatest in individuals with impaction (OR = 3.22, CI = 1.716-6.05, p < 0.001). Maxillary results were similar. Conclusion Third molar impaction plays a role in anterior crowding. Third molar presence was not associated with anterior crowding, while agenesis did not explain absence of crowding.
Measurement of bone mineral density in the tunnel regions for anterior cruciate ligament reconstruction by dual-energy X-ray absorptiometry, computed tomography scan, and the immersion technique based on Archimedes' principle.
Tie, Kai; Wang, Hua; Wang, Xin; Chen, Liaobin
To determine, for anterior cruciate ligament (ACL) reconstruction, whether the bone mineral density (BMD) of the femoral tunnel was higher than that of the tibial tunnel, to provide objective evidence for choosing the appropriate diameter of interference screws. Two groups were enrolled. One group comprised 30 normal volunteers, and the other comprised 9 patients with ACL rupture. Dual-energy X-ray absorptiometry was used to measure the BMD of the femoral and tibial tunnel regions of the volunteers' right knees by choosing a circular area covering the screw fixation region. The knees were also scanned by spiral computed tomography (CT), and the 3-dimensional reconstruction technique was used to determine the circular sections passing through the longitudinal axis of the femoral and tibial tunnels. Grayscale CT values of the cross-sectional area were measured. Cylindrical cancellous bone blocks were removed from the femoral and tibial tunnels during the ACL reconstruction for the patients. The volumetric BMD of the bone blocks was measured using a standardized immersion technique according to Archimedes' principle. As measured by dual-energy X-ray absorptiometry, the BMD of the femoral and tibial tunnel regions was 1.162 ± 0.034 g/cm(2) and 0.814 ± 0.038 g/cm(2), respectively (P < .01). The CT value of the femoral tunnel region was 211.7 ± 11.5 Hounsfield units, and the value of the tibial tunnel region was 104.9 ± 7.4 Hounsfield units (P < .01). The volumetric BMD of the bone block from the femoral tunnel (2.80 ± 0.88 g/cm(3)) was higher than the value from the tibial tunnel (1.88 ± 0.59 g/cm(3)) (P < .01). Comparing the data between male and female patients, we found no significant difference in both femoral and tibial tunnel regions. For ACL reconstruction, the BMD of the femoral tunnel is higher than that of the tibial tunnel. This implies that a proportionally larger-diameter interference screw should be used for fixation in the proximal tibia than that
Boratto, R; Gambardella, U; Micheletti, P; Pagliani, L; Preda, L; Hansson, T L
The aim of this study is to evaluate the possibility to recognize a condylar-mandibular asymmetry through a panoramic radiograph. Results from a previous work, in which 100 skulls from the Museum of the Institute of Anatomy of the University of Pavia were studied and measured, showed the presence of asymmetry. Using the same skulls we examined the possible correlation between morphological and radiological data. We did not find out correlation's between the condylar asymmetry evaluated at the anatomical level and the radiological asymmetry which was indeed found. This is probably due to the different positioning of the jaws during the two different measuring processes. Nevertheless our results confirm the daily experience of dentistry: asymmetry of mandibular condyle can be one of the mayor causes for the asymmetry of the stomatognatic apparatus.
He, Y.; Zhang, M.; Huang, A. Y.; Cui, Y.; Bai, D.; Warman, M. L.
Mice are commonly used to study the temporomandibular joint (TMJ) and to model human TMJ disease. However, evaluating TMJ pathology in mice using standard histologic methods is time consuming, labor intensive, and dependent upon investigators’ expertise at consistently orienting and sectioning across tiny specimens. We describe a method that uses confocal microscopy to rapidly and reliably assess indicators of mandibular condyle cartilage pathology in mice. We demonstrate the utility of this method for detecting abnormalities in chondrocyte distribution in mice lacking lubricin (Prg4), the major boundary lubricant of articular cartilage. We further show that the method can provide information about recombination sites and efficiency in mandibular cartilage for Cre-driver strains. Because specimen preparation and data acquisition with confocal microscopy are simple and fast, the method can serve as a primary screening tool for TMJ pathology, before proceeding to complicated, time consuming, secondary analyses. PMID:28266618
Tatara, A M; Wong, M E; Mikos, A G
Large mandibular defects are difficult to reconstruct with good functional and aesthetic outcomes because of the complex geometry of craniofacial bone. While the current gold standard is free tissue flap transfer, this treatment is limited in fidelity by the shape of the harvested tissue and can result in significant donor site morbidity. To address these problems, in vivo bioreactors have been explored as an approach to generate autologous prefabricated tissue flaps. These bioreactors are implanted in an ectopic site in the body, where ossified tissue grows into the bioreactor in predefined geometries and local vessels are recruited to vascularize the developing construct. The prefabricated flap can then be harvested with vessels and transferred to a mandibular defect for optimal reconstruction. The objective of this review article is to introduce the concept of the in vivo bioreactor, describe important preclinical models in the field, summarize the human cases that have been reported through this strategy, and offer future directions for this exciting approach.
Wessberg, G A; Hill, S C; Epker, B N
Various surgical techniques for a mandibular vestibuloplasty have been advocated. A transpositional labial flap technique used by us for 23 patients since May 1976, and based on a procedure described by Edlan, has been presented with results of nine-month follow-up examinations of six patients. Clinical, radiographic, and histological evaluations completed at three-month intervals showed that this transpositional vestibuloplasty compared favorably with other similar techniques in postoperative time of healing, condition of attached mucosa, stability of increased vestibular depth, and amount of resorption of labial bone. Advantages of this procedure over other mandibular vestibuloplasty techniques are its simplicity, low morbidity, decreased operating time, feasibility of use of local anesthesia and conscious sedation on an outpatient basis, and elimination of the need for a graft. The disadvantage of the procedure is that it requires healthy preexisting vestibular mucosa for optimal results.
Yura, Shinya; Ohga, Noritaka; Ooi, Kazuhiro; Izumiyama, Yuri
A case of unilateral coronoid hyperplasia successfully treated by coronoidotomy with prolonged postoperative physiotherapy and reveal the postoperative radiographic changes between the sectioned part of the coronoid process and the mandibular ascending ramus is described. The patient was a 28-year-old man whose maximum mouth opening was 30 mm. A coronoidotomy of the left coronoid process was performed. Nine days after surgery, the patient started physiotherapy with a HU-OS(r) appliance. After coronoidotomy and physiotherapy, the maximum mouth opening had increased to 43 mm. Radiographic follow-up showed that the coronoid process apparently united with the mandibular ascending ramus, with moderate dislocation and inclination posteriorly. In the case presented, an intraoral coronoidotomy with postoperative physiotherapy for treatment of coronoid process hyperplasia allowed satisfactory and stable results in the correction of coronoid-malar interference.
Kovacić, Ksenija; Hajnzić, Tomislav F; Roncević, Sanja; Hat, Josip; Markicević-Ruzicić, Karmen; Kusić, Zvonko
The case of a six-month-old boy with mandibular Caffey's disease is described. Emphasis is placed on the role of bone scintigraphy, as a diagnostic method which would be, because of the clinical picture and the beginning of the disease (suspected osteomyelitis), one of the first methods performed. Highly characteristic scintigraphic image, when the mandible is involved, can play the most important role in further treatment, and its recognition can also spare many unnecessary procedures.
Canut, J A
The complex variety of clinical problems posed by the lower molars requires maximum care in diagnosis and in treatment planning. In this article several therapeutic solutions to these problems are presented. The need to treat positional anomalies of the second molars and to control their drifting in cases of bracing and mandibular insertion, may be an effective auxillary means of treatment of those malocclusions in which lengthening of the dental bracing zones is indicated.
Bilateral mandibular angle fractures, while representing a rarity among mandibular fractures, are a huge challenge of complex management for the maxillofacial surgeon. There are still many open questions regarding the ideal management of such fractures, including the following: the removal of the third molar in the fracture line, the best surgical approach, and the fixation methods. In this report the authors present the case of 40-year-old man presenting with a bilateral mandibular angle fracture referred to the Maxillofacial Surgery Department of Turin. Open reduction and internal fixation has been made for both sides. The left side third molar was removed and the internal fixation was achieved through internal fixation with one miniplate according to Champy's technique and transbuccal access for a 4-hole miniplate at the inferior border of the mandible. Right side third molar was not removed and fixation was achieved through intraoral access and positioning of a 4-hole miniplate along the external ridge according to Champy. An optimal reduction was achieved and a correct occlusion has been restored. PMID:28299228
de Gouveia, Marcia Maria; Alves, Carlos Augusto Ferreira; Migliolo, Rodrigo Chenu
Mandibular gunshot injuries are esthetically and functionally devastating, causing comminuted fractures and adjacent tissue destruction depending on the weapon gauge, projectile shape, impact kinetic energy, and density of the injured structures. If the mandibular fracture is not adequate or promptly treated, the broken fragments will fail to heal. In case of a treatment delay, progressive bone loss and fracture contracture will require a customized approach, which includes open reduction, removal of fibrous tissue between the bony stumps, and fixation of the fracture with a reconstruction plate and autogenous graft. The authors report the case of a 34-year-old man wounded on the mandible 15 years ago. With the aid of computed tomography and a prototype, a surgical plan was designed including open reduction and internal fixation of the segmental mandibular defect with a reconstruction plate and bone graft harvested from the iliac crest. The postoperative follow-up was uneventful and the 12-month follow up showed a positive aesthetic and functional result. PMID:26484326
Nasseh, Ibrahim; Aoun, Georges
One of the rare anatomical variations that can be of significant importance for the dentist is the bifid mandibular canal. Many complications can occur from this condition such as failure of anesthesia when performing inferior alveolar nerve block, difficulties during the surgical extraction of the third mandibular molar, and during implants placement. Therefore, good knowledge of this condition is essential. In this report, we describe the radiographic finding of a unilateral bifid mandibular canal. PMID:27777715
Shahid, Fazal; Khamis, Mohd Fadhli
Objective The primary aim of the study was to generate new prediction equations for the estimation of maxillary and mandibular canine and premolar widths based on mandibular incisors and first permanent molar widths. Methods A total of 2,340 calculations (768 based on the sum of mandibular incisor and first permanent molar widths, and 1,572 based on the maxillary and mandibular canine and premolar widths) were performed, and a digital stereomicroscope was used to derive the the digital models and measurements. Mesiodistal widths of maxillary and mandibular teeth were measured via scanned digital models. Results There was a strong positive correlation between the estimation of maxillary (r = 0.85994, r2 = 0.7395) and mandibular (r = 0.8708, r2 = 0.7582) canine and premolar widths. The intraclass correlation coefficients were statistically significant, and the coefficients were in the strong correlation range, with an average of 0.9. Linear regression analysis was used to establish prediction equations. Prediction equations were developed to estimate maxillary arches based on Y = 15.746 + 0.602 × sum of mandibular incisors and mandibular first permanent molar widths (sum of mandibular incisors [SMI] + molars), Y = 18.224 + 0.540 × (SMI + molars), and Y = 16.186 + 0.586 × (SMI + molars) for both genders, and to estimate mandibular arches the parameters used were Y = 16.391 + 0.564 × (SMI + molars), Y = 14.444 + 0.609 × (SMI + molars), and Y = 19.915 + 0.481 × (SMI + molars). Conclusions These formulas will be helpful for orthodontic diagnosis and clinical treatment planning during the mixed dentition stage. PMID:27226963
Friedland, S; Winterkorn, J M; Burde, R M
We present five patients who developed luxury perfusion following anterior ischemic optic neuropathy in whom fluorescein angiography was misinterpreted as "capillary hemangioma" or neovascularization of the disc. In each case, the segment of disc hyperemia corresponded to a spared region of visual field. Luxury perfusion represents a reparative autoregulatory reaction to ischemia.
Apparent diffusion coefficient measurements in diffusion-weighted magnetic resonance imaging of the anterior mediastinum: inter-observer reproducibility of five different methods of region-of-interest positioning.
Priola, Adriano Massimiliano; Priola, Sandro Massimo; Parlatano, Daniela; Gned, Dario; Giraudo, Maria Teresa; Giardino, Roberto; Ferrero, Bruno; Ardissone, Francesco; Veltri, Andrea
To investigate inter-reader reproducibility of five different region-of-interest (ROI) protocols for apparent diffusion coefficient (ADC) measurements in the anterior mediastinum. In eighty-one subjects, on ADC mapping, two readers measured the ADC using five methods of ROI positioning that encompassed the entire tissue (whole tissue volume [WTV], three slices observer-defined [TSOD], single-slice [SS]) or the more restricted areas (one small round ROI [OSR]), multiple small round ROI [MSR]). Inter-observer variability was assessed with interclass correlation coefficient (ICC), coefficient of variation (CoV), and Bland-Altman analysis. Nonparametric tests were performed to compare the ADC between ROI methods. The measurement time was recorded and compared between ROI methods. All methods showed excellent inter-reader agreement with best and worst reproducibility in WTV and OSR, respectively (ICC, 0.937/0.874; CoV, 7.3 %/16.8 %; limits of agreement, ±0.44/±0.77 × 10(-3) mm(2)/s). ADC values of OSR and MSR were significantly lower compared to the other methods in both readers (p < 0.001). The SS and OSR methods required less measurement time (14 ± 2 s) compared to the others (p < 0.0001), while the WTV method required the longest measurement time (90 ± 56 and 77 ± 49 s for each reader) (p < 0.0001). All methods demonstrate excellent inter-observer reproducibility with the best agreement in WTV, although it requires the longest measurement time. • All ROI protocols show excellent inter-observer reproducibility. • WTV measurements provide the most reproducible ADC values. • ROI size and positioning influence ADC measurements in the anterior mediastinum. • ADC values of OSR and MSR are significantly lower than other methods. • OSR and WTV methods require the shortest and longest measurement time, respectively.
Madrid, C; Lefebvre, D; Gineste, L; Duran, D; Combelles, R; Roux, P; Joly, R; Laveran, A
Although the infratemporal region is well defined anatomically, its complex topography has been the subject of numerous, and sometimes, opposite works. That is the reason why it appeared necessary for the authors to re-evaluate this topic using the original method of Combelles and Boyer, allowing to define three referential planes, and thereby, a tridimensional shape and the volume of this region. This study allows to conclude that the infratemporal region is a triangular prism with an horizontal main axis 47 mm long. Its anterior base has a mean area of 733 mm2. The posterior top consists of the Juvara slot and has a mean area of 490 mm2. This infratemporal prism contains another one, the pterygomandibular space, prismatic too. It widens out from coronoïd plane (93 mm2) to mandibular foramen plane (169 mm2) before ending as a narrow groove between the neck of the mandibular condyle and the interpterygoïd fascia. The volume of the pterygomandibular space is quite superior to the value usually reported in the dental literature. It is of 4.8 ml to 5.8 ml according to denture. These results point out the opportunity to accomodate more important volumes of anesthesic solutions, than the 1.8 ml usually performed, without any leak out of the infratemporal region.
Nakamura, Hiroko; Sowa, Yoshihiro; Nishino, Kenichi
Background: Surgical cutting guides are used in mandibular reconstruction involving osteotomy of the mandible and fibula. Cutting guides produced using computer-aided design (CAD) and computer-aided manufacturing (CAM) technologies have been reported recently. These guides aim to increase the benefits to patients by improving the accuracy, shortening the operating time, and correcting occlusion. However, the availability of these advanced technologies is limited in some regions of the world. To test whether we could produce low-cost surgical cutting guides, we made surgical guides and investigated their accuracy. Methods: Using free CAD software, we designed surgical cutting guides for the mandible and fibula and used these to perform virtual mandibular segmental osteotomies and fibula transplants in 12 model surgeries. The cutting guides were printed on a 3-dimensional (3D) printer. The model surgeries were performed using 3D mandibular models and cutting guides to check their accuracy. Deviations between the virtually simulated plan and the actual model surgery were investigated. Results: CAD and CAM technologies were used to design and 3D print the cutting guides and models. The guided surgeries were performed. The deviations were about 1.3 mm for mandibular osteotomy, less than 1 mm for fibular osteotomy, and within 2.4 mm for reconstructions of the mandible. Conclusions: Without using expensive software or products, we were able to design surgical cutting guides for the mandible and fibula and used these to perform virtual simulation of mandibular segmental osteotomy and fibular reconstruction. Model surgeries using 3D-printed surgical guides showed that the accuracy of reconstruction was within a 3-mm deviation. In circumstances where commercial CAD/CAM guides are not available, it may be possible to use CAD/CAM surgical guides in the clinic if doctors are willing to volunteer their time for the design and printing. PMID:27536484
Caballero, Giselle Milagros; Carvalho Filho, Osvaldo Abadia de; Hargreaves, Bernardo Oliveira; Brito, Hélio Henrique de Araújo; Magalhães Júnior, Pedro Américo Almeida; Oliveira, Dauro Douglas
Mandibular canines are anatomically extruded in approximately half of the patients with a deepbite. Although simultaneous orthodontic intrusion of the 6 mandibular anterior teeth is not recommended, a few studies have evaluated individual canine intrusion. Our objectives were to use the finite element method to simulate the segmented intrusion of mandibular canines with a cantilever and to evaluate the effects of different compensatory buccolingual activations. A finite element study of the right quadrant of the mandibular dental arch together with periodontal structures was modeled using SolidWorks software (Dassault Systèmes Americas, Waltham, Mass). After all bony, dental, and periodontal ligament structures from the second molar to the canine were graphically represented, brackets and molar tubes were modeled. Subsequently, a 0.021 × 0.025-in base wire was modeled with stainless steel properties and inserted into the brackets and tubes of the 4 posterior teeth to simulate an anchorage unit. Finally, a 0.017 × 0.025-in cantilever was modeled with titanium-molybdenum alloy properties and inserted into the first molar auxiliary tube. Discretization and boundary conditions of all anatomic structures tested were determined with HyperMesh software (Altair Engineering, Milwaukee, Wis), and compensatory toe-ins of 0°, 4°, 6°, and 8° were simulated with Abaqus software (Dassault Systèmes Americas). The 6° toe-in produced pure intrusion of the canine. The highest amounts of periodontal ligament stress in the anchor segment were observed around the first molar roots. This tooth showed a slight tendency for extrusion and distal crown tipping. Moreover, the different compensatory toe-ins tested did not significantly affect the other posterior teeth. The segmented mechanics simulated in this study may achieve pure mandibular canine intrusion when an adequate amount of compensatory toe-in (6°) is incorporated into the cantilever to prevent buccal and lingual crown
Ramakrishnan, Reshma; Shrivastava, Saurabh; Deshpande, Shrikant; Patkar, Priyanka
Dengue fever is caused by a flavivirus. This infection is endemic in the tropics and warm temperate regions of the world. Ocular manifestations of dengue fever include subconjunctival, vitreous, and retinal haemorrhages; posterior uveitis; optic neuritis; and maculopathies, haemorrhage, and oedema. However anterior ischemic optic neuropathy is a rare presentation. Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree and produce optic disc oedema. Here we present a case of anterior ischemic optic neurapathy associated with dengue fever. PMID:27843231
Ramakrishnan, Reshma; Shrivastava, Saurabh; Deshpande, Shrikant; Patkar, Priyanka
Dengue fever is caused by a flavivirus. This infection is endemic in the tropics and warm temperate regions of the world. Ocular manifestations of dengue fever include subconjunctival, vitreous, and retinal haemorrhages; posterior uveitis; optic neuritis; and maculopathies, haemorrhage, and oedema. However anterior ischemic optic neuropathy is a rare presentation. Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree and produce optic disc oedema. Here we present a case of anterior ischemic optic neurapathy associated with dengue fever.
Hegde, Gautham; Hegde, Nanditha; Kumar, Anil; Keshavaraj
Objective: Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. Materials and Methods: A total of 160 periapical radiographs, of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian's stages of dental calcification and the modified MP3 stages. Results and Discussion: The correlation coefficient between MP3 stages and developmental stages of mandibular canine was found to be significant in both male and female groups. When the canine calcification stages were compared with the MP3 stages it was found that with the exception of the D stage of canine calcification the remaining stages showed a very high correlation with the modified MP3 stages. Conclusion: The correlation between the mandibular canine calcification stages, and the MP3 stages was found to be significant. The canine calcification could be used as a sole indicator for assessment of skeletal maturity. PMID:25210386
Hegde, Gautham; Hegde, Nanditha; Kumar, Anil; Keshavaraj
Orthodontic diagnosis and treatment planning for growing children must involve growth prediction, especially in the treatment of skeletal problems. Studies have shown that a strong association exists between skeletal maturity and dental calcification stages. The present study was therefore taken up to provide a simple and practical method for assessing skeletal maturity using a dental periapical film and standard dental X-ray machine, to compare the developmental stages of the mandibular canine with that of developmental stages of modified MP3 and to find out if any correlation exists, to determine if the developmental stages of the mandibular canine alone can be used as a reliable indicator for assessment of skeletal maturity. A total of 160 periapical radiographs, of the mandibular right canine and the MP3 region was taken and assessed according to the Dermirjian's stages of dental calcification and the modified MP3 stages. The correlation coefficient between MP3 stages and developmental stages of mandibular canine was found to be significant in both male and female groups. When the canine calcification stages were compared with the MP3 stages it was found that with the exception of the D stage of canine calcification the remaining stages showed a very high correlation with the modified MP3 stages. The correlation between the mandibular canine calcification stages, and the MP3 stages was found to be significant. The canine calcification could be used as a sole indicator for assessment of skeletal maturity.
Khorshidi, Hooman; Raoofi, Saeed; Ghapanchi, Janan; Shahidi, Shoaleh; Paknahad, Maryam
Estimation of the relative position of infra alveolar nerve (IAN) canal and its relation to the mandibular anatomical landmarks can be clinically useful in minimizing the risk of surgery complications such as neurosensory disturbances that may occur after invasive mandibular surgical procedures. The purpose of the present study was to investigate the anatomic location and radiographic course of the mandibular canal compared to anatomic landmarks on CBCT and to discuss its clinical significance and also to determine the possible correlations between the mandibular position and the age of the patients. This cross sectional study was conducted on 242 CBCT of patients (99 males and 143 females). The location of canal was evaluated in 4 different regions. The first section in trans-axial view after mental foramen, in which the loop of mandibular canal is formed, was selected as point 1 for measurement and intervals of 10 mm, respectively, points 2, 3, 4 were selected for measurement. On these sections, the shortest linear distances (mm) from the most buccal and lingual aspects of the canal to the corresponding cortical plates of the mandible and also the minimum linear distance between the inferior aspect of canal and inferior border of mandible in these regions were calculated. There was statistically significant correlation between the anatomic course of the canal and the patients' gender. The mean vertical position of the canal, as measured from the lower border of the IAN canal to the inferior border of the mandible, was 8.50 mm, ranging from 4.80 to 14.50 mm. On average, the mandibular canal was situated more lingually at all sites to the point it reached the mental foramen. However, at the mental foramen region (Point 1), it was located closer to the buccal cortical plate. Assessment of the exact course of the IAN preoperatively along the body of the mandible by using CBCT might contribute to efficient and accurate surgical planning and therefore positively
Ambelil, Manju; Sultana, Sadia; Roy, Suvra; Gonzalez, Maria M
Anaplastic transformation of well-differentiated thyroid carcinomas at distant metastatic sites is a rare condition. Most cases described in the literature have occurred in the thyroid or regional lymph nodes. We report a case of anaplastic transformation of the follicular variant of papillary thyroid carcinoma in mandibular metastases. A 76-year-old female presented with a painful and enlarging mandibular mass. She had been treated in the past for the follicular variant of papillary thyroid carcinoma. A palliative hemi-mandibulectomy was performed. Histology revealed a metastatic papillary thyroid carcinoma, follicular variant, with an unusual finding of solid pleomorphic epithelioid and spindle cell areas, consistent with anaplastic transformation.
Korotkikh, N G; Oreshkin, A V
The results of treatment are analyzed in 51 patients (35 with exacerbation of chronic traumatic mandibular osteomyelitis and 16 with chronic traumatic mandibular osteomyelitis). Low-intensity pulsed magnetic therapy of the focus in combination with electric stimulation of segmentary bioactive points, synchronized by the patient's pulse, are proposed to be added to the therapeutic complex. Such a modality improved the regional hemodynamics, promoted liquidation of the postoperative edema on days 1-2 after intervention, and sooner than after traditional therapy repaired the energy of the patient's organism.
De Clerck, Hugo; Nguyen, Tung; de Paula, Leonardo Koerich; Cevidanes, Lucia
Introduction Conventional treatment for young Class III patients involves extraoral devices designed to either protract the maxilla or restrain mandibular growth. The use of skeletal anchorage offers a promising alternative to obtain orthopedic results with fewer dental compensations. Our aim was to evaluate 3-dimensional changes in the mandibles and the glenoid fossae of Class III patients treated with bone-anchored maxillary protraction. Methods Twenty-five consecutive skeletal Class III patients between the ages of 9 and 13 years (mean age, 11.10 ± 1.1 year) were treated with Class III intermaxillary elastics and bilateral miniplates (2 in the infrazygomatic crests of the maxilla and 2 in the anterior mandible). The patients had cone-beam computed tomography images taken before initial loading and at the end of active treatment. Three-dimensional models were generated from these images, registered on the anterior cranial base, and analyzed by using color maps. Results Posterior displacement of the mandible at the end of treatment was observed in all subjects (posterior ramus: mean, 2.74 ± 1.36 mm; condyles: mean, 2.07 ± 1.16 mm; chin: mean, −0.13 ± 2.89 mm). Remodeling of the glenoid fossa at the anterior eminence (mean, 1.38 ± 1.03 mm) and bone resorption at the posterior wall (mean, −1.34 ± 0.6 mm) were observed in most patients. Conclusions This new treatment approach offers a promising alternative to restrain mandibular growth for Class III patients with a component of mandibular prognathism or to compensate for maxillary deficiency in patients with hypoplasia of the midface. Future studies with long-term follow-up and comparisons with facemask and chincup therapies are needed to better understand the treatment effects. PMID:22748987
de Araujo, Melissa Rodrigues; Scariot, Rafaela; Uetanabaro, Lucas; Luvison Gomes da Silva, Larissa; Giovanini, Allan Fernando
Xanthoma is a very rare bone tumor, especially in the mandible, that can be associated with metabolic diseases such as hyperlipidemia. A 14-year-old girl presented with a non-corticated unilocular radiolucent lesion observed on panoramic radiography. The lesion was located between the roots of the left first and second premolar teeth, extending from the cervical to the apical region, measuring approximately 1 cm in greatest dimension. An excisional biopsy revealed foam cells and occasional nonfoamy mononuclear macrophage-like cells spread among a discrete fibrous stroma. Immunohistochemically, the xanthomatous cells were CD68 and vimentin positive, focally positive for S100, CD1a, and CD3 and negative for AE1/AE3, CD20, CD117, and HMB45. Hematologic and biochemical investigations ruled out systemic disease.
... this page: //medlineplus.gov/ency/presentations/100230.htm Anterior cruciate ligament repair - Series—Normal anatomy To use the sharing ... to slide 5 out of 5 Overview The anterior cruciate ligament (ACL) is a ligament in the center of ...
Huynh-Le, Phuong; Natori, Yoshihiro; Sasaki, Tomio
We studied the surgical anatomy of the anterior clinoid process (ACP) and its adjacent structures in cadaver heads. We paid special attention to the anatomical relationships between the ACP and adjacent structures to determine the surgical landmarks for safe anterior clinoidectomy. Thirty-five cadaver heads were dissected and the ACP regions were examined in 55 skull sides. We observed that in eight sides the ACP had been pneumatized from the sphenoid sinus. The caroticoclinoid foramen was revealed in only eight sides. The extra-ocular nerves ran forward to the superior orbital fissure at the inferolateral aspect of the ACP, with the oculomotor nerve being closest. The posterolateral area of the carotico-oculomotor membrane was thin and incomplete in nine sides. The study clarified the anatomical relationship between the ACP and its surrounding structures, and identified the major variations experienced. We used these to identify anatomical landmarks to assist the surgeon in the planning of a safe and effective anterior clinoidectomy.
Vela-Hernández, Arturo; López-García, Rocio; García-Sanz, Verónica; Paredes-Gallardo, Vanessa; Lasagabaster-Latorre, Felicidad
To (1) evaluate the efficacy of build-ups in the correction of anterior open bite in adults, (2) evaluate their efficacy in producing molar intrusion, (3) analyze skeletal and dental changes, and (4) assess the long-term stability. The sample consisted of 93 lateral cephalograms from 31 patients with skeletal and dental anterior open bite. The patients had received orthodontic treatment consisting of bonded resin blocks on the maxillary molars combined with Tip-Edge Plus bracket appliances. Cephalometric measurements were performed on radiographs taken before treatment (T1), after treatment (T2), and after a retention period (T3), which were analyzed and compared. Significant dental and skeletal changes were observed after treatment. Molar intrusion averaging 1 mm; 1.44 and 1.57 mm extrusion of mandibular and maxillary incisors, respectively; and a mean of 3.98 mm overbite increase were observed. The mandibular plane angle showed a mean closure of 1.19°, and there was a mean decrease in anterior facial height of 0.7 mm. A mild relapse tendency was observed, but long-term stability was acceptable. Build-ups are an effective treatment alternative for anterior open bite in adults. Outcomes remain significantly stable during the retention period.
Guo, Christine C; Gorno-Tempini, Maria Luisa; Gesierich, Benno; Henry, Maya; Trujillo, Andrew; Shany-Ur, Tal; Jovicich, Jorge; Robinson, Simon D; Kramer, Joel H; Rankin, Katherine P; Miller, Bruce L; Seeley, William W
The neural organization of semantic memory remains much debated. A 'distributed-only' view contends that semantic knowledge is represented within spatially distant, modality-selective primary and association cortices. Observations in semantic variant primary progressive aphasia have inspired an alternative model featuring the anterior temporal lobe as an amodal hub that supports semantic knowledge by linking distributed modality-selective regions. Direct evidence has been lacking, however, to support intrinsic functional interactions between an anterior temporal lobe hub and upstream sensory regions in humans. Here, we examined the neural networks supporting semantic knowledge by performing a multimodal brain imaging study in healthy subjects and patients with semantic variant primary progressive aphasia. In healthy subjects, the anterior temporal lobe showed intrinsic connectivity to an array of modality-selective primary and association cortices. Patients showed focal anterior temporal lobe degeneration but also reduced physiological integrity throughout distributed modality-selective regions connected with the anterior temporal lobe in healthy controls. Physiological deficits outside the anterior temporal lobe correlated with scores on semantic tasks and with anterior temporal subregion atrophy, following domain-specific and connectivity-based predictions. The findings provide a neurophysiological basis for the theory that semantic processing is orchestrated through interactions between a critical anterior temporal lobe hub and modality-selective processing nodes.
Kumari, Pushpa; Roy, S. K.; Roy, Indranil Dev; Rajput, A. K.; Prasanna Kumar, M. P.; Datana, Sanjeev; Rahman, Serat
Aim: To study the changes in posterior airway space (PAS) and mandibular plane hyoid (MPH) distance following mandibular advancement using distraction osteogenesis (DO). Subjects and Methods: A prospective study was conducted at a tertiary care dental center from May 2009 to May 2014. Twenty-five consecutively operated patients of mandibular hypoplasia who underwent mandibular advancement using distraction with at least 12 months follow-up were included in the study. The study group comprised 15 males and 10 females with an age range of 15–30 years (mean 22 years). Presurgical and postsurgical cephalometric changes were compared to determine the changes in PAS and MPH distance. Results: The mean distraction achieved was 14.50 mm. The mean preoperative MPH was 18.88 mm and mean postoperative MPH was 13.16 mm with a resultant reduction by 32%. Mean preoperative PAS was 6.48 mm and mean postoperative PAS was 11.08 mm. Mean increase in PAS was 75%. Mean preoperative and postoperative SNB values were 75.4° and 79.52°, respectively. The results were statistically analyzed using paired “Student's t-test.” Conclusion: From this study, it is concluded that statistically significant changes were achieved in MPH and SNB. Although change in PAS was statistically insignificant, it may have clinical applications, especially in the field of Phase II surgical management of obstructive sleep apnea. PMID:28299255
Rizk, Susan; Kulbersh, Valmy Pangrazio; Al-Qawasmi, Riyad
To evaluate the effects of functional appliance treatment on the oropharyngeal airway volume, airway dimensions, and anteroposterior hyoid bone position of growing Class II patients. Twenty Class II white patients (mean age, 11.7 ± 1.75 years) treated with the MARA followed by fixed appliances were matched to an untreated control sample by cervical vertebrae maturation stage at pretreatment (T1) and posttreatment (T2) time points. Cone beam computed tomography scans were taken at T1 and T2. Dolphin3D imaging software was used to determine oropharyngeal airway volume, dimensions, and anteroposterior hyoid bone position. Multivariate ANOVA was used to evaluate changes between T1 and T2. Oropharyngeal airway volume, airway dimensions, and A-P position of the hyoid bone increased significantly with functional appliance treatment. SNA and ANB decreased significantly in the experimental group (P ≤ .05). Changes in SNB and Sn-GoGn failed to reach statistical significance. Functional appliance therapy increases oropharyngeal airway volume, airway dimensions, and anteroposterior hyoid bone position in growing patients.
Kaul, Raman; O’Brien, Mara H.; Dutra, Eliane; Lima, Alexandro; Utreja, Achint; Yadav, Sumit
Objective The purpose of this study was to delineate the cellular, mechanical and morphometric effects of altered loading on the mandibular condylar cartilage (MCC) and subchondral bone. We hypothesized that altered loading will induce differentiation of cells by accelerating the lineage progression of the MCC. Materials and Methods Four-week-old male Dkk3 XCol2A1XCol10A1 mice were randomly divided into two groups: (1) Loaded-Altered loading of MCC was induced by forced mouth opening using a custom-made spring; (2) Control-served as an unloaded group. Mice were euthanized and flow cytometery based cell analysis, micro-CT, gene expression analysis, histology and morphometric measurements were done to assess the response. Results Our flow cytometery data showed that altered loading resulted in a significant increase in a number of Col2a1-positive (blue) and Col10a1-positive (red) expressing cells. The gene expression analysis showed significant increase in expression of BMP2, Col10a1 and Sox 9 in the altered loading group. There was a significant increase in the bone volume fraction and trabecular thickness, but a decrease in the trabecular spacing of the subchondral bone with the altered loading. Morphometric measurements revealed increased mandibular length, increased condylar length and increased cartilage width with altered loading. Our histology showed increased mineralization/calcification of the MCC with 5 days of loading. An unexpected observation was an increase in expression of tartrate resistant acid phosphatase activity in the fibrocartilaginous region with loading. Conclusion Altered loading leads to mineralization of fibrocartilage and drives the lineage towards differentiation/maturation. PMID:27472059
DiDomenico, Lawrence A; Masternick, Eric B
Compression of the deep peroneal nerve is commonly referred to as anterior tarsal tunnel syndrome. Although rare, this syndrome remains poorly diagnosed. The syndrome is characterized by pain, weakness, and sensory changes of the foot and ankle. Non-operative measures should be attempted to reduce or remove the external compression along the anterior aspect of the foot and ankle. Other options include shoe modifications, cortisone injections,and physical therapy. If conservative management fails to relieve the symptoms, surgical decompression of the entrapped nerve can be performed. The deep peroneal nerve is released from compressive forces in the entrapment site. This can be performed at the more proximal level at the extensor retinaculum or more distally at the level of the tarsal metatarsal site.
Pitzer, G; Oursin, C; Wolfensberger, M
An anterior neopharyngeal pseudodiverticulum is a mucosal pouch located between the tongue and hypopharynx due to an epiglottis-like posterior tissue band that forms after total laryngectomy. This condition has rarely been mentioned in literature. Incidence, symptoms, treatment, and possible etiologic factors were examined. Twenty post-laryngectomy patients were questioned about swallowing disorders and were examined clinically and by barium swallow. Eleven patients were found to have a pseudodiverticulum, of which 9 patients suffered from dysphagia. We found no correlation between the formation of a pseudodiverticulum and radiotherapy or post-laryngectomy complications. All symptomatic patients were treated by dissecting the posterior tissue band endoscopically with a CO2-laser, bringing complete relief of symptoms in 8 of 9 patients. Our study showed that the anterior pseudodiverticulum can be a frequent cause of dysphagia after laryngectomy. It can easily be diagnosed clinically and radiologically. Endoscopic treatment with a CO2-laser is simple and effective.
Grondin, Francis; Hall, Toby; von Piekartz, Harry
Gross mandibular position and masticatory muscle activity have been shown to influence cervical muscles electromyographic activity. The purpose of this study was to investigate the influence of three different mandible positions including conscious occlusion, tongue tip against the anterior hard palate (Palate tongue position) and natural resting position (Rest), on sagittal plane cervical spine range of motion (ROM) as well as the flexion-rotation test (FRT) in asymptomatic subjects. An experienced single blinded examiner evaluated ROM using an Iphone in 22 subjects (7 females; mean age of 29.91years, SD 5.44). Intra-rater reliability for range recorded was good for the FRT with ICC (intraclass correlation) 0.95 (95% CI: 0.88-0.98) and good for sagittal plane cervical ROM with ICC 0.90 (95% CI: 0.77-0.96). A repeated measures ANOVA determined that mean ROM recorded during the FRT differed significantly between assessment points (F(1.99, 41.83) = 19.88, P < 0.001). Bonferroni Post hoc tests revealed that both conscious Occlusion and Palate tongue position elicited a significant large reduction in ROM recorded during the FRT from baseline (p < 0.01). Despite this, one activation strategy did not influence ROM more than the other. An additional repeated measures ANOVA determined that mean sagittal cervical ROM did not significantly vary between assessment points (F(2, 42) = 8.18, P = 0.08). This current study provided further evidence for the influence of the temporomandibular region on upper cervical ROM. Results suggest that clinicians should focus on the natural mandible rest position when evaluating upper cervical mobility. Copyright © 2016 Elsevier Ltd. All rights reserved.
Der-Martirosian, Claudia; Gironda, Melanie W.; Black, Edward E.; Belin, Thomas R.; Atchison, Kathryn A.
Background Patient treatment preferences do not necessarily remain stable over time. Objective This study focuses on predictors of patient treatment choice and on the extent to which patients are willing to take risks by choosing surgical versus non-surgical treatment for mandibular fracture. Methods Surveys of African-American and Hispanic adults receiving treatment at King/Drew Medical Center for either a mandibular fracture (n = 98) or third-molar removal (n = 105) were used to investigate patterns of patient preference over the course of a 4-month study period using generalized estimating equations controlling for age, gender, income, and fracture versus third-molar patient. The study examined the effects of symptom rating and a “standard gamble” measure reflecting a patient’s willingness to accept scarring or nerve damage. This analysis is based on 169 patients who participated in four waves of data collection. Results The most salient predictor of patient treatment was the standard gamble measure at 1-month follow-up. Subjects with higher risk tolerance were more likely to select surgery versus jaw wiring. A higher likelihood of choosing surgery was associated with higher income and greater symptom severity. Fracture patients were more likely to select surgery compared with third-molar patients. Conclusions The significance of symptom severity 1-month post-surgery raises an important issue regarding the healing process. Moreover, the significance of standard gamble as a predictor of treatment choice for mandibular fracture should encourage other researchers to use this measure of willingness to accept risk when studying acute conditions such as jaw fracture. PMID:19694938
Der-Martirosian, Claudia; Gironda, Melanie W; Black, Edward E; Belin, Thomas R; Atchison, Kathryn A
Patient treatment preferences do not necessarily remain stable over time. This study focuses on predictors of patient treatment choice and on the extent to which patients are willing to take risks by choosing surgical versus nonsurgical treatment for mandibular fracture. Surveys of African-American and Hispanic adults receiving treatment at King/Drew Medical Center for either a mandibular fracture (n = 98) or third-molar removal (n = 105) were used to investigate patterns of patient preference over the course of a 4-month study period using generalized estimating equations controlling for age, gender, income, and fracture versus third-molar patient. The study examined the effects of symptom rating and a"standard gamble" measure reflecting a patient's willingness to accept scarring or nerve damage. This analysis is based on 169 patients who participated in four waves of data collection. The most salient predictor of patient treatment was the standard gamble measure at 1-month follow-up. Subjects with higher risk tolerance were more likely to select surgery versus jaw wiring. A higher likelihood of choosing surgery was associated with higher income and greater symptom severity. Fracture patients were more likely to select surgery compared with third-molar patients. The significance of symptom severity 1-month post-surgery raises an important issue regarding the healing process. Moreover, the significance of standard gamble as a predictor of treatment choice for mandibular fracture should encourage other researchers to use this measure of willingness to accept risk when studying acute conditions such as jaw fracture.
Wall, C E
The Megaladapidae have a posterior expansion of the articular surface of the mandibular condyle. Several other strepsirhine species exhibit a similar condylar surface. In this study, I propose two behavioral scenarios in which the posterior articular expansion might function: 1) contact with the postglenoid process and resistance to joint stress during browsing, and 2) movement against the postglenoid process during the fast closing and power strokes of mastication, as a consequence of large transverse jaw movements and associated with a strong mandibular symphysis. These models are evaluated through dissection of the TMJ in Lepilemur and from comparative anatomical observations on strepsirhines and ungulates. In Lepilemur the mandibular symphysis is unfused, but compared to the unfused symphyses of other strepsirhines is strengthened by interlocking bony projections (Beecher  Am. J. Phys. Anthropol. 47:325-336). An accessory articular meniscus is found between the posterior articular expansion and the postglenoid process in Lepilemur, suggesting that significant movement occurs in this part of the TMJ. The symphysis is fused in adult specimens of Megaladapis. A posterior articular expansion is common among ungulates, and its presence is associated not with browsing but with symphyseal fusion. This supports the second model and suggests that the posterior articular expansion functions as a movement surface during mastication. Schwartz and Tattersall ( J. Hum. Evol. 16:23-40) cite the posterior articular expansion as a synapomorphy uniting an Adapis-Leptadapis clade with a Megaladapidae-Daubentonia-Indridae clade. The comparative evidence suggests that the posterior articular expansion has evolved convergently in adapines, notharctines, megaladapids, hapalemurids, and indrids as part of a functional complex related to herbivory. However, close morphological similarity of the posterior articular expansion among genera within these strepsirhine subfamilies
Gormley, M; Philip, J; James, R; Heaton, M
This report describes a good example of the rare fourth branch of the marginal mandibular nerve. This case emphasizes the need for respecting the variation in the marginal mandibular nerve when carrying out surgery. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.
Sooriaprakas, Chandrasekaran; Ballal, Suma; Velmurugan, Natanasabapathy
Successful endodontic management of mandibular first molar with a single root and single canal is diagnosed with the aid of dental operating microscope and multiple angled radiographs. In addition all the mandibular molars and premolars were single rooted on either side. PMID:24715990
Kommers, Sofie C.; Roccia, Fabio; Forouzanfar, Tymour
Objectives: The aim of this study was to evaluate the treatment of mandibular fractures treated in two European centre in 10 years. Study Design: This study is based on 2 systematic computer-assisted databases that have continuously recorded patients hospitalized with maxillofacial fractures in two centers in Turin, Italy and in Amsterdam, the Netherlands for ten years. Only patients who were admitted for mandibular fractures were considered for this study. Results: Between 2001 and 2010, a total of 752 patients were admitted at Turin hospital with a total of 1167 mandibular fractures not associated with further maxillofacial fractures, whereas 245 patients were admitted at Amsterdam hospital with a total of 434 mandibular fractures. At Amsterdam center, a total of 457 plates (1.5 - 2.7 mm) were used for the 434 mandibular fracture lines, whereas at Turin center 1232 plates (1.5 – 2.5 mm) were used for the management of the 1167 mandibular fracture lines. At Turin center, 190 patients were treated primarily with IMF, whereas 35 patients were treated with such treatment option at Amsterdam center. Conclusions: Current protocols for the management of mandibular fractures are quite efficient. It is difficult to obtain a uniform protocol, because of the difference of course of each occurring fracture and because of surgeons’ experiences and preferences. Several techniques can still be used for each peculiar fracture of the mandible. Key words:Mandibular fracture, facial trauma, maxillofacial, treatment, multicentre, database. PMID:25475782
Abdalla, Wael; Panigrahy, Ashok; Bartoletti, Stefano C
Cerebro-costo-mandibular syndrome (CCMS) is a rare syndrome that includes a constellation of mandibular hypoplasia and posterior rib defects as its basic features. Additional features can include hearing loss, tracheal cartilage abnormalities, scoliosis, elbow hypoplasia, and spina bifida. Here we report two cases of CCMS and discuss the reported long-term outcome of the disease.
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Mandibular implant facial prosthesis. 874.3695 Section 874.3695 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular...
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Mandibular implant facial prosthesis. 874.3695 Section 874.3695 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular...
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Mandibular implant facial prosthesis. 874.3695 Section 874.3695 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular...
Fernandes, Sérgio Augusto; Vellini-Ferreira, Flávio; Scavone-Junior, Helio; Ferreira, Rívea Inês
To achieve proper recontouring of anterior and posterior teeth, to obtain optimal morphology during enamel stripping, it is important to be aware of dental anatomy. This study aimed at evaluating crown dimensions and proximal enamel thickness in a sample of 40 extracted sound, human, mandibular, second bicuspids (20 right and 20 left). Mesiodistal, cervico-occlusal and buccolingual crown dimensions were measured using a digital caliper, accurate to 0.01 mm. Teeth were embedded in acrylic resin and cut along their long axes through the proximal surfaces to obtain 0.7 mm-thick central sections. Enamel thickness on the cut sections was measured using a perfilometer. Comparative analyses were carried out using the Student's-t test (α= 5%). The mean mesiodistal crown widths for right and left teeth were 7.79 mm (± 0.47) and 7.70 mm (± 0.51), respectively. Mean cervico-occlusal heights ranged from 8.31 mm (± 0.75) on the right to 8.38 mm (± 0.85) on the left teeth. The mean values for the buccolingual dimension were 8.67 mm (± 0.70) on the right and 8.65 mm (± 0.54) on the left teeth. The mean enamel thickness on the mesial surfaces ranged from 1.35 mm (± 0.22) to 1.40 mm (± 0.17), on the left and right sides, respectively. On the distal surfaces, the corresponding values were 1.44 mm (± 0.21) and 1.46 mm (± 0.12). No significant differences were found between measurements for right and left teeth. However, enamel thickness was significantly greater on the distal surfaces, compared with the mesial surfaces.
Singh, Harpreet; Srivastava, Dhirendra; Kapoor, Pranav; Sharma, Poonam
This case report describes the successful treatment of a patient with mandibular laterognathism and associated facial asymmetry with combined surgical orthodontic approach. After 7 months of presurgical orthodontic treatment, intraoral vertical ramus osteotomy, and straightening genioplasty were performed as two step surgeries to reposition the deviated mandible and chin, respectively. The total active treatment period was 14 months. After surgical orthodontic treatment, significant improvement in occlusion, masticatory function, and facial appearance was discernible. Posttreatment records at 3 years showed stable results with good occlusion. PMID:27127755
Karun, Vinayak; Agarwal, Navneet; Singh, Virendra
Introduction: Management of mandibular deformities is challenging. Distraction osteogenesis is a relatively new technique with promising results. Materials and Methods: We selected 12 patients. The osteotomy site decided was proximal to the antegonial notch. Latency time was five to seven days. Consolidation period was eight weeks in eleven cases and six weeks in one case. Results: In all the patients, appreciable lengthening of mandible was achieved. Discussion: The greatest advantage of distraction osteogenesis is growth of soft tissue along with the growth of hard tissue. This increases post operative stability PMID:24665178
Yang, Renkai; Tang, Xiaojun; Shi, Lei; Yin, Lin; Yang, Bin; Yin, Hongyu; Liu, Wei; Zhang, Zhiyong
To analyze the effect of mandibular distraction on the maxilla growth in children with hemifacial microsomia through measurement with the posterior-anterior cephalometric X-ray films and Three-dimensional CT reconstruction images. The deviation angular of maxilla occlusion plane and nasal base plane from the infra-orbital plane were measured on the posterior-anterior cephalometric X-ray films in 22 patients before and half a year after operation. The vertical distance from the midpoint of 5th teeth alveolar and the lowest point of maxillary sinus to reference plane were measured on 3D reconstruction images in 15 patients. The data were statistically analyzed. On posterior-anterior cephalometric X-ray films, the cant of occlusion plane were significantly reduced (P < 0.05), While the angular of nasal base plane and the infra-orbital plane had no significant change. On 3D reconstruction images, all the detection points had significantly declined except the lowest point of maxillary sinus on normal side. Distraction osteogenesis of mandible can promote the growth of the maxilla in children with HFM, the accelerated growth parts include alveolar bone and maxillary sinus.
Amorim, Vânia Cristina Pintaudi; Laganá, Dalva Cruz; de Paula Eduardo, José Virgilio; Zanetti, Artemio Luiz
The influence of the loss of posterior teeth on the condylar position and on temporomandibular disorders (TMDs) remains a controversial issue. This study investigated whether prosthetic rehabilitation promoted modification of the condylar position in subjects without symptoms of TMDs. The temporomandibular joints (TMJs) of 12 women (age 37 to 74), all with existing maxillary complete dentures but no removable partial denture (RPD) restoring the Kennedy class I partially edentulous mandibular arch and no clinical signs of TMDs according to the criteria established by Helkimo, were viewed in maximal intercuspal position with corrected lateral tomography before and after prosthetic rehabilitation with a new maxillary complete denture and a mandibular RPD. Before prosthetic rehabilitation, a mandibular stabilizing base was fabricated to prevent the existing maxillary complete denture from dislodging during tomographic examination. Two methods were used to evaluate tomograms: (1) linear measurements of the subjective narrowest anterior and posterior intra-articular joint spaces made from the tomograms by use of a digital caliper and (2) linear measurements of the anterior and posterior intra-articular joint spaces on the basis of drawings and tracings. Repeated-measures analysis of variance followed by orthogonal contrasts were used to evaluate differences between measurements carried out on the same subject under the different test conditions of the study (before prosthetic rehabilitation, before prosthetic rehabilitation with a mandibular stabilizing base in position, and after prosthetic rehabilitation) (P<.05). Before prosthetic rehabilitation, a predominance of posterior condylar positions was observed. Before prosthetic rehabilitation with a mandibular stabilizing base in position, a significant decrease was observed in posterior condylar positions (P=.03). This decrease was more marked after prosthetic rehabilitation (P=.02). The subjective evaluation and
Sforza, Chiarella; Ugolini, Alessandro; Rocchetta, Davide; Galante, Domenico; Mapelli, Andrea; Giannì, Aldo Bruno
We recorded three-dimensional mandibular movements, while the mouth was being opened and closed, using an optoelectronic motion analyser in 14 patients (5 skeletal Class II, 9 skeletal Class III) who were being assessed 7-49 months after orthognathic operations, and in 44 healthy subjects. All 14 patients had satisfactory healing on clinical examination, and function had been restored. Mandibular movement was divided into its rotational and translational components. On maximum mouth opening, the patients had significantly less total displacement of the mandibular interincisor point (p=0.05), and more mandibular movement that was explained by pure condylar rotation (p=0.006), than control subjects. There was no significant relation between maximum mouth opening and percentage rotation. While mandibular motion was well restored clinically by orthognathic surgery, the kinematics of the joint were modified. Larger studies and longitudinal investigations are necessary to appreciate the clinical relevance of the variations in condylar rotational and translational components.
Castroflorio, Tommaso; Icardi, Katia; Torsello, Ferruccio; Deregibus, Andrea; Debernardi, Cesare; Bracco, Pietro
The aim of this study was to test the hypothesis that surface electromyography (sEMG) recordings, made at mandibular rest position from the masseter and temporalis anterior areas, are intra- and inter-session reproducible. A template was designed and built to permit the correct electrode placement from one session to the next session. A sample of 18 subjects was examined. Two groups, homogeneous for age, sex, and craniofacial morphology were selected. The first group included asymptomatic subjects with no signs or symptoms of temporomandibular joint dysfunction (TMD) and the second group included patients suffering from muscle-related TMD. Data were obtained from different sEMG recordings made at mandibular rest position in the same session and in different sessions, repositioning the electrodes using a template designed for that purpose. The electromyograph used in this, study is part of the EMG K6-I Win Diagnostic System. Results showed that reproducibility of sEMG signals from the masseter and anterior temporalis areas at mandibular rest position is possible.
Franchi, L; Baccetti, T; McNamara, J A
The analysis of mandibular growth changes around the pubertal spurt in humans has several important implications for the diagnosis and orthopedic correction of skeletal disharmonies. The purpose of this study was to evaluate mandibular shape and size growth changes around the pubertal spurt in a longitudinal sample of subjects with normal occlusion by means of an appropriate morphometric technique (thin-plate spline analysis). Ten mandibular landmarks were identified on lateral cephalograms of 29 subjects at 6 different developmental phases. The 6 phases corresponded to 6 different maturational stages in cervical vertebrae during accelerative and decelerative phases of the pubertal growth curve of the mandible. Differences in shape between average mandibular configurations at the 6 developmental stages were visualized by means of thin-plate spline analysis and subjected to permutation test. Centroid size was used as the measure of the geometric size of each mandibular specimen. Differences in size at the 6 developmental phases were tested statistically. The results of graphical analysis indicated a statistically significant change in mandibular shape only for the g