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1

New Approaches in Vital Pulp Therapy in Permanent Teeth  

PubMed Central

Vitality of dental pulp is essential for long-term tooth survival. The aim of vital pulp therapy is to maintain healthy pulp tissue by eliminating bacteria from the dentin-pulp complex. There are several different treatment options for vital pulp therapy in extensively decayed or traumatized teeth. Pulp capping or pulpotomy procedures rely upon an accurate assessment of the pulp status, and careful management of the remaining pulp tissue. The purpose of this review is to provide an overview of new approaches in vital pulp therapy in permanent teeth. PMID:24396371

Ghoddusi, Jamileh; Forghani, Maryam; Parisay, Iman

2014-01-01

2

Maturogenesis of non-vital immature permanent teeth  

PubMed Central

Pulpal necrosis in young permanent teeth often results in teeth with open apex, thin root walls and poor crown root ratio. Out of the available treatment options maturogenesis has been the most conservative option that exploits full potential of pulp for dentin deposition. Maturogenesis involves disinfecting the root canal system followed by stimulation of blood clot from the periapical tissue, which provides a matrix into which the cell could grow and sealing the coronal excess. In the present case report, tri antibacterial paste (3 Mix) was used as an intracanal medicament that proved successful in stimulating vital pulp cells of the periapical region for maturogenesis. Five months radiograph follow-up showed thickening of lateral dentinal walls, which progress until 15 months resulting in apical closure, thickening of lateral dentinal walls and increase root length. PMID:24015025

Kalaskar, Ritesh R.; Kalaskar, Ashita R.

2013-01-01

3

Dentin Bonding: SEM Comparison of the Resin-Dentin Interface in Primary and Permanent Teeth  

Microsoft Academic Search

Previous studies have suggested minor differences between primary and permanent teeth in terms of dentin composition and morphology. Other reports indicated lower bond strengths of resin composites to dentin of primary teeth compared with dentin of permanent teeth; however, no information is available regarding differences in the micromorphology of the resin-dentin interface that may explain these lower bond strengths. Therefore,

J. E. Nor; R. J. Feigal; J. B. Dennison; C. A. Edwards

1996-01-01

4

Traumatic injuries to permanent teeth in Turkish children, Ankara.  

PubMed

The aim of this study was to identify the types and etiologies of dento-alveolar injuries among patients who were treated for injuries to maxillary and/or mandibular permanent teeth at the Gulhane Medical Academy, Department of Pediatric Dentistry, Center of Dental Sciences in Ankara, Turkey to provide a basis for determining optimal treatment approaches and educational needs. From a total of 4956 children aged 6-12 years (mean age: 8.91 +/- 1.95) applying to the Center, 472 children (9.5%) were found to have suffered dental injuries during a period of 2 years. Injuries were classified according to drawings and texts based on the WHO classification system, as modified by Andreasen and Andreasen. Injury rates were highest among children age 6 and ages 8-10. The most frequently injured permanent teeth were the maxillary central incisors (88.2%), and the maxillary right central permanent incisor made up 47.2% of all injured teeth. The most common cause of dental trauma was falling while walking or running (40.3%). Most injuries involved a single tooth (64.8%). The most common type of injury was enamel fracture (44.6%). There was a significant difference in gender, where boys more often suffered from a dental hard tissue and pulp injury than girls (P = 0.019), whereas there was no difference in gender (P = 0.248) in the distribution of periodontal injuries. Injuries were found to occur more frequently during the summer (P < 0.001). Children with increased overjet were 2.19 times more likely to have dental injuries than other children. Considering that the incidence of traumatic dental injury is highest among children ages 6 and ages 8-10 as well as the fact that patients with increased overjet are more prone to dental trauma, preventive orthodontic treatment in early mixed dentition may play an important role in reducing traumatic dental injuries. PMID:19583580

Altun, Ceyhan; Ozen, Bu?ra; Esenlik, Elçin; Guven, Günseli; Gürbüz, Ta?kin; Acikel, Cengizhan; Basak, Feridun; Akbulut, Erman

2009-06-01

5

Angle Class II malocclusion treated with extraction of permanent teeth.  

PubMed

Angle Class II malocclusion associated with anterior open bite in adult patients demands a carefully elaborated orthodontic planning, aiming at restoring not only harmonious dental and facial esthetics, but also a balanced masticatory function. Orthognathic surgery or permanent teeth extraction are often the choice of treatment, therefore, treatment decision is related to all dental, skeletal and functional aspects. The present report discusses orthodontic compensation carried out by means of upper premolar extraction performed to correct the Class II canine relationship and, consequently, the anterior open bite, accepting that the upper incisors be retroclined. This clinical case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as part of the requirements for obtaining the BBO Certification. PMID:24262426

Barreto, Gustavo Mattos

2013-01-01

6

Boon of MTA Apexification in Young Permanent Posterior Teeth  

PubMed Central

Single visit apexification using mineral trioxide aggregate (MTA) is a new boon in effective management of nonvital tooth with an open apex which has steadily gained popularity with clinicians; also it shortens the treatment period and improves patient compliance. Importance of this approach lies in expedient cleaning and shaping of the root canal system, followed by its apical seal with MTA. There are several case reports available describing the use of MTA as an apexification agent in incisors and premolar, but presented cases are the unique case reports demonstrating successful apexification procedure using MTA in young permanent mandibular molars. After eight-month follow-up, teeth were without any abnormal clinical symptoms; rather there were radiographic resolution of the periapical lesion and induction of root end closure with new hard tissue formation over MTA.

Kumar, Vinod; Prasad, Vijaya; Mahantesh, T.

2014-01-01

7

Bond strength with various etching times on young permanent teeth  

SciTech Connect

Tensile bond strengths of an orthodontic resin cement were compared for 15-, 30-, 60-, 90-, or 120-second etching times, with a 37% phosphoric acid solution on the enamel surfaces of young permanent teeth. Fifty extracted premolars from 9- to 16-year-old children were used for testing. An orthodontic composite resin was used to bond the bracket directly onto the buccal surface of the enamel. The tensile bond strengths were tested with an Instron machine. Bond failure interfaces between bracket bases and teeth surfaces were examined with a scanning electron microscope and calculated with mapping of energy-dispersive x-ray spectrometry. The results of tensile bond strength for 15-, 30-, 60-, or 90-second etching times were not statistically different. For the 120-second etching time, the decrease was significant. Of the bond failures, 43%-49% occurred between bracket and resin interface, 12% to 24% within the resin itself, 32%-40% between resin and tooth interface, and 0% to 4% contained enamel fragments. There was no statistical difference in percentage of bond failure interface distribution between bracket base and resin, resin and enamel, or the enamel detachment. Cohesive failure within the resin itself at the 120-second etching time was less than at other etching times, with a statistical significance. To achieve good retention, to decrease enamel loss, and to reduce moisture contamination in the clinic, as well as to save chairside time, a 15-second etching time is suggested for teenage orthodontic patients.

Wang, W.N.; Lu, T.C. (School of Dentistry, National Defense Medical Center, Taipei, Taiwan (China))

1991-07-01

8

Bacteria of Dental Caries in Primary and Permanent Teeth in Children and Young Adults  

Microsoft Academic Search

Although Streptococcus mutans has been implicated as a major etiological agent of dental caries, our cross-sectional preliminary study indicated that 10% of subjects with rampant caries in permanent teeth do not have detectable levels of S. mutans. Our aims were to use molecular methods to detect all bacterial species associated with caries in primary and permanent teeth and to determine

Jørn A. Aas; Ann L. Griffen; Sara R. Dardis; Alice M. Lee; Ingar Olsen; Floyd E. Dewhirst; Eugene J. Leys; Bruce J. Paster

2008-01-01

9

Characterization of the Apical Papilla and Its Residing Stem Cells from Human Immature Permanent Teeth: A Pilot Study  

Microsoft Academic Search

Mesenchymal stem cells (MSCs) have been isolated from the pulp tissue of permanent teeth (dental pulp stem cells or DPSCs) and deciduous teeth (stem cells from human exfoliated deciduous teeth). We recently discovered another type of MSCs in the apical papilla of human immature permanent teeth termed stem cells from the apical papilla (SCAP). Here, we further characterized the apical

Wataru Sonoyama; Yi Liu; Takayoshi Yamaza; Rocky S. Tuan; Songlin Wang; Songtao Shi; George T.-J. Huang

2008-01-01

10

A review of pulp therapy for primary and immature permanent teeth.  

PubMed

The aim of pulp therapy in primary and young permanent teeth is to maintain a functional tooth so that arch integrity is preserved in a growing child. History, clinical evaluation and radiographic findings should be integrated to arrive at pulp diagnosis. Vital pulp therapy should be attempted whenever the pulp is diagnosed to be vital. Nonvital pulp therapy should be performed for strategically important primary teeth. Revascularization is an emerging technique for immature necrotic teeth. PMID:24073497

Ritwik, Priyanshi

2013-08-01

11

Surgical management of multiple supernumerary teeth and an impacted maxillary permanent central incisor.  

PubMed

Hyperdontia is the condition of having supernumerary teeth, or teeth which appear in addition to the regular number of teeth. It is a developmental anomaly and has been argued to arise from multiple aetiologies. The most common site is the maxillary incisor region; but the prevalence of more than three teeth supernumerary tooth is less than 1%. A case of 13 year male patient is reported with a multiple impacted supernumerary tooth in maxillary anterior region hindering the eruption of right permanent central incisor. The supernumerary tooth was treated via surgical approach followed by an interim prosthesis for permanent central incisor which later on erupted in due course of time. Background Supernumerary teeth may be defined as any teeth or tooth substance in excess of the usual configuration of 20 deciduous and 32 permanent teeth. The presence of supernumerary teeth in the premaxillary region often poses unique diagnostic and managerial concerns for the practitioner. Rarely is the surplus number compensated by an absence or deficiency of other teeth. Therefore, the dysfunctional nature of supernumerary teeth and their ability to create a variety of pathological disturbances in the normal eruption and position of adjacent teeth warrants their early detection and prudent management. Approximately 76-86% of cases represent single-tooth hyperdontia, with two supernumerary teeth noted in 12-23% and three or more extra teeth noted in less than 1% of cases. Multiple supernumerary teeth are also associated with many syndromes like cleidocranial dysplasia and Gardner’s syndrome etc. However, it is rare to find multiple supernumeraries in individuals with no other associated disease or syndrome. In such cases, the maxillary anterior region is the common site of occurrence. The exact aetiology is not clearly understood. The supernumerary teeth result from any disturbance in the initiation and proliferation stages of odontogenesis. There are several theories regarding the development of a supernumerary tooth-phylogenetic reversion (atavism) theory, dichotomy of tooth germ theory and hyperactivity of the dental lamina. The latter being the most accepted theory, states that the remnants of dental lamina or palatal offshoots of active dental lamina are induced to develop into an extra tooth bud, which results in the formation of a supernumerary tooth. Genetics is also considered to contribute to the development of supernumerary teeth, as these have been diagnosed in twins, siblings and sequential generations of a family. Classification of supernumerary teeth may be on the basis of position or form. Positional variations include mesiodens, paramolars, distomolars and parapremolars. Variations in form consist of conical types, tuberculate types, supplemental teeth and odontomes. Supernumerary teeth may, therefore, vary from a simple odontome, through a conical or tuberculate tooth to a supplemental tooth which closely resembles a normal tooth. Also, the site and number of supernumeraries can vary greatly. This report presents a case of a non-syndromic male patient with multiple supernumerary teeth and a permanent impacted tooth in the maxillary anterior region. PMID:23704467

Rallan, Mandeep; Rallan, Neelakshi Singh; Goswami, Mousumi; Rawat, Kamini

2013-01-01

12

Angle Class I malocclusion with anterior open bite treated with extraction of permanent teeth.  

PubMed

This clinical case reports the orthodontic treatment of a Class I malocclusion with anterior open bite and bimaxillary dentoalveolar protrusion in a 28-year-old female patient. The treatment of choice was to perform tooth extractions followed by retraction of the anterior teeth, with consequent closure of the anterior open bite and better accommodation of the teeth on their bony bases. This case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO), representing the Category 2 -- i.e., an Angle Class I malocclusion, with anterior open bite, treated with extraction of permanent teeth --, as part of the requisites to become a BBO diplomate. PMID:23916443

Pithon, Matheus Melo

2013-01-01

13

Cogging torque and acoustic noise reduction in permanent magnet motors by teeth pairing  

Microsoft Academic Search

This paper investigates reduction of cogging torque and acoustic noise in permanent magnet motors with larger stator slot opening. Using an energy method with Fourier series expansion, cogging torque is analytically determined with airgap MMF function and airgap permeance function. It shows that there exist several tooth widths which minimize the cogging torque. It also proposes a teeth pairing with

Sang-Moon Hwang; Jae-Boo Eom; Geun-Bae Hwang; Weui-Bong Jeong; Yoong-Ho Jung

2000-01-01

14

Comparative ablation rate from a Er: YAG laser on enamel and dentin of primary and permanent teeth  

Microsoft Academic Search

This study was conducted to analyze the ablation rate and micromorphological aspects of microcavities in enamel and dentin\\u000a of primary and permanent teeth using a Er: YAG laser system. Micromorphological evaluation has been performed in terms of\\u000a permanent teeth; however, little information about Er: YAG laser interaction with primary teeth can be found in the literature.\\u000a Because children have been

R. de F. Z. Lizarelli; L. T. Moriyama; J. R. P. Jorge; V. S. Bagnato

2006-01-01

15

Can Accidental Local Application of A Drug Cause Discolouration of Permanent Teeth?  

PubMed Central

Thorough knowledge on the aetiology of tooth staining is of importance to dental surgeons, in order to enable a correct diagnosis to be made when examining a discoloured dentition and it allows the dental practitioner to explain to the patient the exact nature of the condition. Tetracyclines are a group of drugs which can discolour teeth permanently. One such case of discolouration of adult teeth caused by administration of tetracycline(oxytetracycline) has been reported here and it has been discussed in detail. PMID:24551734

Hans, Manoj Kumar; Nagpal, Ajay; Shetty, Shashit; Hans, Rinki

2013-01-01

16

Distinctive Genetic Activity Pattern of the Human Dental Pulp between Deciduous and Permanent Teeth  

PubMed Central

Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11–14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR). Other teeth were used for immunohistochemical analysis (IHC). Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1), leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), and gamma-aminobutyric acid A receptor beta 1 (GABRB1) were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration. PMID:25047033

Kim, Ji-Hee; Jeon, Mijeong; Song, Je-Seon; Lee, Jae-Ho; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; DenBesten, Pamela K.; Kim, Seong-Oh

2014-01-01

17

The potential of deciduous and permanent bovine enamel as substitute for deciduous and permanent human enamel: Erosion-abrasion experiments.  

PubMed

Aim of the present study was to compare toothbrushing abrasion of eroded human and bovine enamel utilizing a toothpaste slurry. The surfaces of each 36 teeth from cattle and calves and from each 36 human wisdom teeth and deciduous teeth were polished. Each 12 specimens from the respective tooth type were used for assessing toothbrushing abrasion only (A), erosion only (E) and the combination of erosion and toothbrushing abrasion (EA). The EA samples were subjected to 20 cycles comprising a demineralization/remineralization procedure directly followed by toothbrushing abrasion (100 strokes, 300 g load, toothpaste slurry: 3 ml artificial saliva mixed with 1g dentifrice). Demineralization in form of erosion was performed with 1% citric acid (1 min), remineralization with artificial saliva (15 min). Between the cycles, the samples were stored in artificial saliva. Wear of the treated surfaces with reference to untreated areas was determined profilometrically. The samples subjected to abrasion only (A) did not show a significantly different wear between the different kinds of teeth. The comparisons of substance loss between teeth of different species revealed that hard tissue loss of the human deciduous teeth was significantly lower as compared to calves' teeth after both erosion and erosion-abrasion. Also, both erosion only and erosion-abrasion caused higher enamel loss in cattle's teeth than in human wisdom teeth. It is concluded that human eroded enamel offers better resistance against brushing than bovine enamel. PMID:17709163

Attin, Thomas; Wegehaupt, Florian; Gries, David; Wiegand, Annette

2007-10-01

18

Eruption times of permanent teeth in teenage boys and girls in Izmir (Turkey)  

Microsoft Academic Search

In a study in the Aegean city of Izmir, Turkey, during the summer of 2002, 2101 patients (1046 boys and 1055 girls) were examined. The examination occurred within the framework of a dental check-up performed at two schools and one pre-school unit. The age span ranged from 3.98 to 24.91 years. Sex, age and present permanent teeth were recorded. Wisdom

J. S. Wedl; V. Schoder; F. A. S. Blake; R. Schmelzle; R. E. Friedrich

2004-01-01

19

Growth and development of permanent teeth germ of transplacental Yu-Cheng babies in Taiwan  

SciTech Connect

This paper is intended to present a study of transplacental Yu-Cheng babies in Taiwan. The focus of the study is to demonstrate how a contaminated food source can affect the growth and development of permanent teeth germ in children. A sporadic outbreak of a peculiar skin disease was reported in Japan in October of 1968. An epidemiological study revealed the outbreak of this disease was caused by contaminated Kanemi rice oil. This episode of rice oil poisoned with polychlorinated biphenyls (PCB) was the first reported outbreak of PCB poisoning in the world. A second episode occurred in central Taiwan eleven years after the Japanese episode. Registered data from the Taiwan Provincial Government Health Department reported 1,843 cases in 1980. Of this group, more than 800 women were child-bearing age and most of these women would or soon would be married and pregnant. The offsprings of these women were in danger, because it has been proven that PCB intoxication could affect the fetus. These babies, only contaminated through the placenta, are called PCB transplacental Yusho babies in Japan and PCB transplacental Yu-Cheng babies in Taiwan. Babies with PCB poisoning could have Fetal PCB syndrome (FPS) and may have retarded eruption of permanent teeth and other anomalies such as reduced numbers of teeth and abnormal shaped roots. The study of transplacental Yu-Cheng babies is an important public health issue for Taiwan. Although there may be other issues, this study focuses only on the growth and development of permanent teeth of those babies affected by PCB transplacental contamination.

Lan, Shoujen; Yen, Yeayin; Ko, Yingchin; Chen, Engrin (School of Public Health of Kaohsiung Medical College, Kaohsiung City (Taiwan))

1989-06-01

20

Outcomes of Different Vital Pulp Therapy Techniques on Symptomatic Permanent Teeth: A Case Series  

PubMed Central

In modern endodontics, vital pulp therapy (VPT) has been considered an ultra-conservative treatment modality. Based on the level of pulp preservation, VPT includes stepwise excavation, indirect pulp capping (IDPC), direct pulp capping (DPC), miniature pulpotomy (MP), partial/Cvek pulpotomy and coronal/complete pulpotomy (CP). The present article reviews the treatment outcomes of 94 permanent teeth with irreversible pulpitis treated with either IDPC (n=28), DPC (n=28), MP (n=29) or CP (n=9) using calcium-enriched mixture (CEM) cement. After a mean follow-up time of 12.3 months, 93 treated teeth were radiographic/clinically successful; only one radiographic failure was observed in the DPC group. PMID:25386213

Asgary, Saeed; Fazlyab, Mahta; Sabbagh, Sedigheh; Eghbal, Mohammad Jafar

2014-01-01

21

Crown heights in the permanent teeth of 45,X and 45,X/46,XX females.  

PubMed

Abstract Objective. Previous results regarding human sex chromosome aneuploidies have shown that the X and Y chromosomes affect tooth size and morphology. This study looked for the effect of sex chromosome deficiency on permanent tooth crown heights. Materials and methods. The material, from the Finnish KVANTTI Research Project, consisted of 97 45,X females and 15 45,X/46,XX females. The controls were 32 sisters and 28 mothers of the 45,X females, eight sisters and two mothers of the 45,X/46,XX females and 35 female population controls. Crown heights of all the available teeth except third molars on both sides of the jaws were measured from panoramic radiographs with a digital calliper according to the defined procedure. Results. The tooth crown heights were significantly smaller in the 45,X females than in the female population controls, except for the incisors and one canine in the maxilla, whereas the tooth crown heights of the 45,X/46,XX females were close to those of the normal control females. The differences between the 45,X and 45,X/46,XX females were statistically significant, excluding the upper incisor area and a few teeth in the mandible. Conclusions. The effect of the sex chromosome deficiency on permanent tooth crown height is due to the magnitude of lacking sex chromosome material. The present results regarding the 45,X females are parallel to previous findings in Turner patients regarding reduced mesiodistal and labiolingual dimensions and tooth crown heights in the permanent dentition. PMID:24882680

Pentinpuro, Raija Helena; Lähdesmäki, Raija Eliisa; Niinimaa, Ahti Olavi; Pesonen, Paula Ritva Orvokki; Alvesalo, Lassi Juhani

2014-11-01

22

Tensile bond strength of sealants following Er:YAG laser etching compared to acid etching in permanent teeth  

Microsoft Academic Search

The aim of this in vitro study was to assess the effect of Er:YAG laser surface treatment on the tensile bond strength of\\u000a a sealant in permanent teeth. A total of 30 sound third molars were selected and embedded in cold-cure acrylic resin. The\\u000a enamel surfaces were flattened by a grinding. The teeth were randomly divided into three groups and

Sima Shahabi; Hossein G. Bagheri; Kosar Ramazani

23

A biochemical and histopathological evaluation of generalized pulp calcification in young permanent teeth.  

PubMed

Pulp calcifications are a frequent finding on bitewing and periapical radiographs in older age-groups but their occurrence in the entire dentition in young subjects is unusual. We report such an unusual occurrence of generalized pulp calcification in a 13-year-old Indian female. Radiographic examination of the dentition revealed pulp calcifications in all permanent teeth, located mostly in the pulp chamber but with some in the root canals. The patient's dental, medical, and family history was noncontributory. Biochemical analysis of the removed pulp calcification from one of the teeth during endodontic treatment showed large amounts of calcium, phosphorus, and carbonate. However, metabolic evaluation of patient through liver and kidney function tests and other blood investigations did not reveal any metabolic disorder. The patient was also evaluated for any systemic, syndromic, or genetic involvement but this was also noncontributory. Therefore, we propose that this unusual case of generalized pulp calcification is of idiopathic origin. In this work, histopathological and biochemical evaluations of the pulp calcification was done to try and understand the initiation and progress of calcifications in pulpal tissue. PMID:22842270

Bahetwar, S K; Pandey, Ramesh Kumar; Singh, Rajeev Kumar; Bahetwar, T S; Wahid, Ali

2012-01-01

24

Health Instruction Packages: Permanent Teeth, Dental Deposits, and Dental Instruments. Dientes Permanentes, Depositos Dentales y Instrumentos Dentales.  

ERIC Educational Resources Information Center

These five learning modules use text interspersed with illustrations and reinforcement exercises to instruct dental aide and dental hygiene students about jaw bones and gums, dental deposits, and dental instruments. The first four modules were prepared by Patricia Lind in both Spanish and English. "The Gum and Bone of Permanent Teeth" ("La Encia y…

Lind, Patricia; Germano, Catherine

25

Pulpal blood flow in vital and nonvital young permanent teeth measured by transmitted-light photoplethysmography: a pilot study  

Microsoft Academic Search

Purpose: The purpose of this study was to record transmitted-light photoplethys- mography (TLP) from young permanent teeth and examine its applicability to pulp vitality assessment. Methods: Twenty-six healthy and 7 nonvital upper maxillary incisors in 17 children (ages 7 years, 3 months to 14 years, 8 months) were examined. Recordings of TLP were made with and without opaque black rubber

Zenzo Miwa; Motohide Ikaw; Hideyo Iijima; Makoto Saito; Yuzo Takagi

2002-01-01

26

An evaluation of microleakage of various glass ionomer based restorative materials in deciduous and permanent teeth: An in vitro study  

PubMed Central

Aim To evaluate the microleakage of recently available glass ionomer based restorative materials (GC Fuji IX GP, GC Fuji VII, and Dyract) and compare their microleakage with the previously existing glass ionomer restorative materials (GC Fuji II LC) in primary and permanent teeth. Method One hundred and fifty (75 + 75) non-carious deciduous and permanent teeth were restored with glass ionomer based restorative materials after making class I cavities. Samples were subjected to thermocycling after storing in distilled water for 24 h. Two coats of nail polish were applied 1 mm short of restorative margins and samples sectioned buccolingually after storing in methylene blue dye for 24 h. Microleakage was assessed using stereomicroscope. Result Significant differences (P < 0.05) were found when inter group comparisons were done. Except when GC Fuji VII (Group III) was compared with GC Fuji II LC (Group II) and Dyract (Group IV), non-significant differences (P > 0.05) were observed. It was found that there was no statistically significant difference when the means of microleakage of primary teeth were compared with those of permanent teeth. Conclusions GC Fuji IX GP showed maximum microleakage and GC Fuji VII showed least microleakage. PMID:23960526

Singla, Teena; Pandit, I.K.; Srivastava, Nikhil; Gugnani, Neeraj; Gupta, Monika

2011-01-01

27

Assessment of some elements in human permanent healthy teeth, their dependence on number of metallic amalgam fillings, and interelements relationships  

Microsoft Academic Search

In this study, 60 human permanent healthy teeth (without filling) were collected postmortem and analyzed using flame atomic\\u000a absorption spectrometry (FAAS), cold vapor atomic absorption spectrometry (CVAAS), hydride generation atomic absorption spectrometry\\u000a (HGAAS), and electrothermal atomic absorption spectrometry (ETAAS) for the determination of Ca, Hg, Se, Cu, and Ag. The concentration\\u000a of these elements was assessed in carious and noncarious

Mohammad Saber-Tehrani; Mohammad H. Givianrad; Parvin Kahkashan

2007-01-01

28

Circular Enamel Hypoplasia: A Rare Enamel Developmental Disturbance in Permanent Teeth  

PubMed Central

Circular enamel hypoplasia, a type of enamel hypoplasia is an extensive enamel disturbance that results in a demarcating line surrounding the crown of the injured teeth visible both clinically and radiographically that most frequently occurs as a result of trauma in children around the age of two years. Clinical features include poor aesthetics, dentin sensitivity, increased susceptibility to dental caries and malocclusion. Early radiographic diagnosis of such teeth is important for timely intervention and subsequent treatment. PMID:25302282

Gulia, Shweta; Nagpal, Mehak; Sachdev, Vinod

2014-01-01

29

Pulp Revascularization of Immature Permanent Teeth: A Review of the Literature and a Proposal of a New Clinical Protocol  

PubMed Central

Tissue engineering is a growing field. In the near future, it will probably be possible to generate a complete vital tooth from a single stem cell. Pulp revascularization is dependent on the ability of residual pulp and apical and periodontal stem cells to differentiate. These cells have the ability to generate a highly vascularized and a conjunctive rich living tissue. This one is able to colonize the available pulp space. Revascularization is a new treatment method for immature necrotic permanent teeth. Up to now, apexification procedures were applied for these teeth, using calcium dihydroxide or MTA to produce an artificial apical barrier. However, the pulp revascularization allows the stimulation of the apical development and the root maturation of immature teeth. Two pulp revascularization techniques are used in the literature, one using calcium dihydroxide and the second using a triple antibiotic paste. Based on these two different pulp revascularization protocols, which obtain the desired therapeutic success, the literature will be reviewed and analyzed according to the relevance of their choice of materials. Based on the literature, we propose a new relevant protocol and a new mixture of antibiotics. PMID:25383384

Namour, Mélanie

2014-01-01

30

Weight, height and eruption times of permanent teeth of children aged 4-15 years in Kampala, Uganda  

PubMed Central

Background Tooth eruption is a continuous biological process by which developing teeth emerge through the jaws and the overlying mucosa to enter into the oral cavity. Tooth eruption time and sequence are important factors in dental treatment planning, particularly in orthodontics, but also in forensic dentistry to estimate age of a child. Tooth eruption time is influenced by many factors. In this study we set out to determine the timing of eruption of permanent teeth and assess its association with the height and weight of school children aged 4–15 years in Kampala, Uganda. Methods This was a cross sectional study comprising of 1041 healthy Ugandan children: boys/girls (520/521) who were consecutively selected from two primary schools in Kampala. The children were clinically assessed for tooth emergency through the oral mucosa as well as measuring their weight and height. The mean and standard deviation of tooth eruption time was estimated for boys and girls. Bivariate analysis was used to assess any significant association between tooth eruption time and demographic variables. Pearson and partial correlation analyses were used to assess any significant association between the tooth eruption time and anthropometric measurements of the children. Results Generally, the mean eruption times for girls were lower compared to boys except for three teeth (#25, #32 and #42) which erupted earlier in boys. The average difference in mean eruption times of all teeth between boys and girls was found to be 0.8 (range, 0–1.5) years. In partial correlation analysis, mean tooth eruption times were positively, but not significantly associated with height while controlling for weight except for the mandibular left central incisor (#31). On the other hand, in partial correlation analysis, mean tooth eruption times were positively associated with weight while controlling for height except for tooth #11, #16, #26 and #41. The weight of the child was significantly correlated with mean eruption times in 50% of the teeth. Conclusion In the present study, the mean tooth eruption times for girls were lower compared to boys except for three teeth (#25, #32 and #42). The height of the child did not show any significant influence on the tooth eruption times while the influence of weight on tooth eruption times was non-conclusive. PMID:23497340

2013-01-01

31

Radiographic assessment of clinical root-crown ratios of permanent teeth in a healthy Korean population  

PubMed Central

PURPOSE The aim of this study was to determine the absolute value of the root/crown ratio (R/C ratio) using panoramic radiographs (PRGs) in a healthy Korean population. MATERIALS AND METHODS In total, 99 patient radiographs (of 50 males and 49 females subjects; aged 16 to 24 years old) were examined, and 2,770 teeth were analyzed. Crown lengths and root lengths were measured with modified Lind's measurements using PACS tools by two examiners in two separate sessions two months apart. All data were analyzed using SPSS. The independent t-test was used to assess for gender differences, and the paired t-test was used to compare both arches with a significance level of P<.05. RESULTS The mean R/C ratios varied from 1.29 to 1.89 (male: 1.28-1.84; females: 1.31-1.94). The highest R/C ratios were recorded for the mandibular canines (1.89), followed by the maxillary canines (1.79). The lowest R/C ratios were recorded for the maxillary second molars (1.31). In comparison with the maxillary teeth (1.29-1.78), the mandibular teeth yielded the higher R/C ratio (1.47-1.89), and this difference was significant in the females (P<.05). The difference between the genders was not statistically significant, except for the maxillary central incisors, mandibular canines and mandibular first premolars. CONCLUSION These data may enhance the understanding of the clinical R/C ratio as a useful guideline for determining the status of teeth and the ethnic difference. PMID:25006380

Yun, Hee-Jung; Jeong, Jin-Sun; Pang, Nan-Sim; Kwon, Il-Keun

2014-01-01

32

Qualitative Histological Evaluation of Hard and Soft Tissue Components of Human Permanent Teeth Using Various Decalcifying Agents - A Comparative Study  

PubMed Central

Introduction: Decalcification is the commonly employed technique in histopathology laboratories as a part of calcified tissue preparation for the microscopic examination. Chemical agents are most commonly used for routine decalcification procedures, though some agents adversely affect the tissue integrity and staining properties. Aim: To compare the efficacy of various decalcifying agents by histological evaluation of hard and soft tissue components of teeth. Materials and Methods: The five decalcifying agents namely 10% Nitric acid (HNO3), 10% Formal nitric acid (FNA), 10 % Formic acid (FA), 8% Potassium formate (KF) + 8% Formic acid (FA) and Neutral Ethylenediamenetetracetic acid (EDTA) were used to decalcify 60 human permanent teeth. The specimens were subjected to routine processing, sectioning and staining with hematoxylin and eosin. The stained sections were observed under light microscope by three independent observers and grading was done. Statistical Analysis: Paired sample t-test was done for inter-observer variation. One-way-ANOVA and Post-hoc test was applied to compare the effects of different decalcifying agents. Results: Considering preservation and staining characteristics of both hard and soft tissues, superior results were obtained with 10% HNO3 followed by 10% FNA and EDTA which was according to the respective mean values obtained. But statistically significant difference was shown only with 10% FA & 8% KF + 8% FA. Conclusion: HNO3 was showing the most efficient result as it balances both tissue integrity and time factor suggesting that it can be used as a stable decalcifying agent for routine histopathological diagnosis. PMID:25386527

Jawanda, Manveen Kaur; SM, Manjunath; Bharti, Achla

2014-01-01

33

Reparative hard tissue formation following calcium hydroxide application after partial pulpotomy in cariously exposed pulps of permanent teeth.  

PubMed

In a prospective study, partial pulpotomy was performed on six permanent molars with deep carious lesions and pulpal involvement. The bleeding pulp was irrigated with normal tap water until bleeding had stopped and the exposed pulp was covered with calcium hydroxide followed by zinc oxide eugenol, and finally covered with a semipermanent restoration. All teeth showed hard tissue barrier formation, both clinically and radiographically, within three months and were free from subjective and objective symptoms through the observation period (average observation period was 26 months). The patients also experienced the therapy positively. These findings and those of others have helped gain more recognition for partial pulpotomy as a strong possible alternative therapy when pulps are exposed by deep carious lesions and a bleeding pulp is exposed during the excavation process. The rationale for this therapy is to remove the infected and/or inflamed pulpal areas beneath the carious lesion and disintegrated tissue. A rapid and simplified procedure would allow the general practitioner to perform this procedure when necessary at dental clinics, without specialist facilities under conditions that avoid unnecessary contamination of the pulp. PMID:10321166

Nosrat, I V; Nosrat, C A

1998-05-01

34

Paediatric dentistryDental fluorosis in permanent incisor teeth in relation to water fluoridation, social deprivation and toothpaste use in infancy  

Microsoft Academic Search

Objectives To determine the prevalence and severity of fluorosis in permanent incisor teeth in young children in a fluoridated and a fluoride-deficient community and to establish what relationship, if any, there was between the occurrence of dental fluorosis and the reported use of fluoride toothpaste in childhood.Design A prevalence study of children aged 8–9 years who had been continuous residents

R Ellwood; A J Rugg-Gunn; D J Evans; R M Davies; E D Tabari

2000-01-01

35

Combined Orthodontic-surgical Treatment for Skeletal Class III Malocclusion with Multiple Impacted Permanent and Supernumerary Teeth: Case Report  

PubMed Central

In this report we describe a combined orthodontic and surgical treatment for a 14-year-old boy with severe skeletal class III deformity and dental problem. His upper posterior primary teeth in the left side were over-retained and 6 maxillary teeth (bilateral central incisors and canines, left first and second premolars) were impacted, together with 5 supernumerary teeth in both arches. The treatment protocol involved extraction of all the supernumerary and deciduous teeth, surgical exposure and orthodontic traction of the impacted teeth, a bimaxillary orthognathic approach including Lefort I osteotomy. Bilateral sagittal split ramus osteotomy (BSSRO) and genioplasty was performed to correct skeletal problem. After treatment, all of the impacted teeth were brought to proper alignment in the maxillary arch. A satisfied profile and good posterior occlusion was achieved. Treatment mechanics and consideration during different stages are discussed. PMID:24893948

Xue, Dai Juan and Feng

2014-01-01

36

[What is the relation between the presence of caries in the deciduous dentition and the chronology of the eruption of the permanent teeth?].  

PubMed

Based on data obtained from a prospective epidemiological study in a random sample of 4468 Flemish children, accurate emergence ages for permanent teeth could be established. When data on permanent tooth emergence in different populations are compared, differences are most pronounced for premolars. Several authors hypothesised that this difference could be explained by a difference in caries experience in the primary molars. The purpose of this study was to quantify the effect of caries experience in a primary molar on the timing of emergence of its successor. The results indicate that the emergence of the premolars was accelerated by 2 to 8 months when its predecessor had been decayed and or filled but had not been extracted. Premature loss of maxillary primary molars resulted in a significant acceleration of the emergence of the premolars; this was not observed in the mandible. In conclusion, when considering permanent tooth emergence ages, caries experience in the primary dentition should be taken into account. PMID:15526648

Leroy, Roos; Declerck, Dominique

2004-01-01

37

Morphogenesis and age-related structure of permanent canine teeth in the brown bear, Ursus arctos L., in Arctic Alaska  

Microsoft Academic Search

Morphogenesis of the canine teeth of the brown bear, Ursus arctos L., is described, based upon 101 skulls from the central Brooks Range, in arctic Alaska. The formation of annual layers in the calcified tissues (dentin and cementum) is attributed to interruption of growth and odontogenesis during the annual period of denning.

Robert L. Rausch

1969-01-01

38

Determination of Frequency of the Second Mesiobuccal Canal in the Permanent Maxillary First Molar Teeth with Magnification Loupes (x 3.5)  

PubMed Central

INTRODUCTION: The mesiobuccal root of the maxillary first molar has generated more research and clinical investigation than any root. An inability to detect and treat a second mesiobuccal (MB2) canal is a reason for endodontic failure in maxillary first molars. Modifications in the endodontic access and detection techniques, along with advancements in illumination and magnification technology, have aided in the location and treatment with the second mesiobuccal canal of maxillary first molars. OBJECTIVE: To determine the frequency of the second mesiobuccal canal in the permanent maxillary first molars with magnification loupes (× 3.5). MATERIALS AND METHODS: A total of 53 teeth were assessed using a moderate magnification for second mesiobuccal canal in mesiobuccal root of first permanent maxillary molars in vivo. Detection of this canal in maxillary first molars was done through a clinical access cavity preparation under magnification loupes (× 3.5). Data was analyzed using SPSS 15.0. Frequency distribution of variables was determined and the level of significance was kept at 0.05. RESULTS: We were able to detect second mesiobuccal canal in 27 out of 53 (50.9%) of the permanent maxillary first molars that were studied. It was found that the males tend to have a higher proportion of second mesiobuccal canals (up to 31%) as compared to the females in whom the second mesiobuccal canals could be identified only 19% of the time. Whilst, there was no association found between age, gender and chamber obliteration with the presence of second mesiobuccal canal. CONCLUSIONS: In conclusion, within its limitations, this study suggested that the use of magnification loupes enhanced both the detection (50.9%) and negotiation (86.8%) of the second mesiobuccal canals in the permanent maxillary first molars beyond what could be achieved with naked eye.

Hasan, Muhammad; Raza Khan, Farhan

2014-01-01

39

Malocclusion of teeth  

MedlinePLUS

... are easier to clean and decrease risk of tooth decay and periodontal diseases ( gingivitis or periodontitis ). Eliminate strain ... braces and may permanently mark teeth or cause tooth decay if not properly cared for. You will need ...

40

Isolation, Characterization and Comparative Differentiation of Human Dental Pulp Stem Cells Derived from Permanent Teeth by Using Two Different Methods  

PubMed Central

Developing wisdom teeth are easy-accessible source of stem cells during the adulthood which could be obtained by routine orthodontic treatments. Human pulp-derived stem cells (hDPSCs) possess high proliferation potential with multi-lineage differentiation capacity compare to the ordinary source of adult stem cells1-8; therefore, hDPSCs could be the good candidates for autologous transplantation in tissue engineering and regenerative medicine. Along with these benefits, possessing the mesenchymal stem cells (MSC) features, such as immunolodulatory effect, make hDPSCs more valuable, even in the case of allograft transplantation6,9,10. Therefore, the primary step for using this source of stem cells is to select the best protocol for isolating hDPSCs from pulp tissue. In order to achieve this goal, it is crucial to investigate the effect of various isolation conditions on different cellular behaviors, such as their common surface markers & also their differentiation capacity. Thus, here we separate human pulp tissue from impacted third molar teeth, and then used both existing protocols based on literature, for isolating hDPSCs,11-13 i.e. enzymatic dissociation of pulp tissue (DPSC-ED) or outgrowth from tissue explants (DPSC-OG). In this regards, we tried to facilitate the isolation methods by using dental diamond disk. Then, these cells characterized in terms of stromal-associated Markers (CD73, CD90, CD105 & CD44), hematopoietic/endothelial Markers (CD34, CD45 & CD11b), perivascular marker, like CD146 and also STRO-1. Afterwards, these two protocols were compared based on the differentiation potency into odontoblasts by both quantitative polymerase chain reaction (QPCR) & Alizarin Red Staining. QPCR were used for the assessment of the expression of the mineralization-related genes (alkaline phosphatase; ALP, matrix extracellular phosphoglycoprotein; MEPE & dentin sialophosphoprotein; DSPP).14 PMID:23208006

Karamzadeh, Razieh; Eslaminejad, Mohamadreza Baghaban; Aflatoonian, Reza

2012-01-01

41

Effects of the diamond grit sizes of the commercial dental diamond points on the weight-load cutting of bovine enamel and glass-ceramic Typodont teeth.  

PubMed

To evaluate the effect of the diamond grit size of commercial dental diamond points on the dental cutting, we conducted weight-load cutting tests on bovine enamel and glass-ceramic typodont teeth using 3 different diamond grit sizes and air-bearing and ball-bearing air-turbine driven handpieces. With the transverse load applied on the diamond point varied between 20 and 80 g, we measured rotational cutting speed and cutting volume. Generally, increases in applied load caused decreases in rotational cutting speed and increases in cutting volume. The intensity of this trend, however, differed between grit sizes. Regular grit diamond points most strongly showed this tendency, while super-fine grit diamond points were least affected. Fine grit diamond points behaved in a manner similar to regular grit points. PMID:1966019

Taira, M; Wakasa, K; Yamaki, M; Matsui, A

1990-12-01

42

Dinosaur Teeth  

NSDL National Science Digital Library

In this classroom activity, middle school students learn what kinds of information can be gained by studying teeth. The activity opens with background information for teachers about dinosaur teeth. Working in small groups, students examine their own teeth; hypothesize about how incisors, canine teeth, and molars are used; and test their hypotheses with carrots. The activity concludes with a student worksheet that challenges them to identify the uses of different dinosaur teeth.

43

Histotomography of the odontoblast processes at the dentine–enamel junction of permanent healthy human teeth in the confocal laser scanning microscope  

Microsoft Academic Search

The translucency of teeth allows the non-destructive subsurface visualisation of their microstructure by confocal laser scanning\\u000a microscopy (CLSM) at a level of about 150 ?m below the surface. The dentine–enamel junction (DEJ) is accessible only directly\\u000a adjacent to the cervix of the tooth. Therefore teeth have to be sectioned for studying marginal areas of the dental hard tissue.\\u000a The potential

K. A. Grötz; H. Duschner; T. E. Reichert; E. G. de Aguiar; H. Götz; W. Wagner

1998-01-01

44

Natal teeth  

MedlinePLUS

... the time of birth. They are different from neonatal teeth, which grow in during the first 30 ... irritation and injury to the infant's tongue when nursing. Natal teeth may also be uncomfortable for a ...

45

A practice-based study on stepwise excavation of deep carious lesions in permanent teeth: a 1-year follow-up study.  

PubMed

This study reports results from a practice-based study in which deep carious lesions were treated by general dental practitioners using stepwise excavation. The material comprised 94 teeth with deep carious lesions which the clinicians considered would result in pulp perforation if treated by a single and terminal excavation. At the first visit excavation of the peripheral dentine was completed. The outermost part of the central and necrotic dentine was gently removed with a sharp excavator. Standardized assessments of the dentine colour and consistency were made before application of a calcium hydroxide-containing base material and temporary filling. The final excavation was completed after a treatment interval ranging from 2 to 19 months, with a median of 6 months. Reassessments of the dentine colour and consistency were made before complete removal of demineralized dentine. The central dentine was significantly browner and less softened after the sealing period. After removal of the dark-brownish dentine during the final excavation, the colour and consistency of the exposed central dentine was found to resemble that of the completely excavated peripheral dentine. Only five cases resulted in pulp perforation during the final excavation. The high success rate of teeth surviving the final treatment without pulp exposure after 1 year of observation shows that it was possible for dentists in general practice to administer and manage the treatment of deep carious lesions, a process which may prolong tooth survival compared with conventional endodontic techniques. PMID:9645406

Bjørndal, L; Thylstrup, A

1998-04-01

46

Teething Tots  

MedlinePLUS

... the first set of teeth will fall out, tooth decay makes them fall out more quickly, leaving gaps ... brush and floss. Another important tip for preventing tooth decay: Don't let your baby fall asleep with ...

47

Sensitive Teeth  

MedlinePLUS

... down, rather than side to side Using a fluoride toothpaste and mouth rinse Using a toothpaste that ... After a cleaning, your dentist may apply a fluoride varnish to protect your teeth. This temporarily reduces ...

48

Teething & Dental Hygiene for Young Children  

MedlinePLUS

... permanent teeth and lead to future dental problems. Teaching Good Dental Habits The best way to protect ... Pediatric First Aid for Caregivers and Teachers (PedFACTs) Teaching Package Food Fights Raising Twins Healthy Living Nutrition ...

49

Caries-preventive effect of glass ionomer and resin-based fissure sealants on permanent teeth: An update of systematic review evidence  

PubMed Central

Background This article constitutes a partial update of the original systematic review evidence by Yengopal et al. from 15 January 2008 (published in the Journal of Oral Science in 2009) with primary focus on research quality in regard to bias risk in trials. Its aim is to update the existing systematic review evidence from the English literature as to whether caries occurrence on pits and fissures of teeth sealed with either GIC or resin is the same. Methods In addition to the 12 trials included during the original systematic review, 5 new trials were identified during the database search (up to 26 August 2010) and 2 further trials were included from a hand search and reference check. Of these, 3 trials were excluded and 16 were accepted for data extraction and quality assessment. The quality of accepted trials was assessed, using updated quality criteria, and the risk of bias was investigated in more depth than previously reported. In addition, the focus of quantitative synthesis was shifted to single datasets that were extracted from the accepted trials. Results Twenty-six dichotomous and 4 continuous datasets were extracted. Meta-analysis and cumulative meta-analysis were used in combining clinically homogenous datasets. The overall outcome of the computed datasets suggest no difference between the caries-preventive effects of GIC- and resin-based fissure sealants. Conclusions This overall outcome is in agreement with the conclusions of the original systematic review. Although the findings of the trials identified in this update may be considered to be less affected by attrition- and publication bias, their risk of selection- and detection-/performance bias is high. Thus, verification of the currently available results requires further high quality randomised control trials. PMID:21276215

2011-01-01

50

Teeth characterization using ion beam analysis  

Microsoft Academic Search

Summary  A collaboration project between the School of Dentistry and the Institute of Physics of the University of São Paulo has been\\u000a established to measure elemental concentrations in teeth by proton induced X-ray emission (PIXE) and heavy ion elastic recoil\\u000a detection analysis (HI-ERDA) techniques. Data on trace elements in human, bovine and swine teeth, analyzed by PIXE with a\\u000a 2.4 MeV

M. A. Rizzutto; N. Added; M. H. Tabacniks; F. Falla-Sotelo; J. F. Curado; C. Francci; R. A. Markarian; A. Quinelato; F. Youssef; M. Mori; M. Youssef

2006-01-01

51

The art and science of managing traumatic injuries to primary teeth.  

PubMed

The selection of an appropriate treatment protocol and the rendering of treatment to children with traumatic injuries of their primary teeth are often more challenging than doing so for the permanent teeth of older individuals. This article discusses general considerations involving patient, parent, dentist, dental anatomy and occlusion that are responsible for the differences between the treatment protocols for the management of traumatic dental injuries to primary teeth and those for permanent teeth. PMID:21535401

Needleman, Howard L

2011-08-01

52

Talon cusp in fused teeth: A rare concomitant occurrence  

PubMed Central

Talon cusp and fusion of teeth are two separate developmental dental anomalies affecting both primary and permanent dentitions. While the former is more common in permanent maxillary incisors, the latter occurs more commonly in deciduous maxillary anterior teeth. This paper describes a rare case of talon cusp in fused teeth affecting the permanent mandibular incisors. A note on the etiopathogenesis of these two anomalies and a possible hypothesis on their concurrent occurrence are mentioned. The importance of awareness and understanding of these lesions and the prophylactic measures to prevent complications is also discussed. PMID:23248476

Thirumalaisamy, Elangovan; Baskaran, Pavitra; Jeyanthi, K; Kumar, Sathya

2012-01-01

53

Talon cusp in fused teeth: A rare concomitant occurrence.  

PubMed

Talon cusp and fusion of teeth are two separate developmental dental anomalies affecting both primary and permanent dentitions. While the former is more common in permanent maxillary incisors, the latter occurs more commonly in deciduous maxillary anterior teeth. This paper describes a rare case of talon cusp in fused teeth affecting the permanent mandibular incisors. A note on the etiopathogenesis of these two anomalies and a possible hypothesis on their concurrent occurrence are mentioned. The importance of awareness and understanding of these lesions and the prophylactic measures to prevent complications is also discussed. PMID:23248476

Thirumalaisamy, Elangovan; Baskaran, Pavitra; Jeyanthi, K; Kumar, Sathya

2012-09-01

54

A 25-year-old man with 50 teeth: Astonishing but true!!  

PubMed Central

Retained primary teeth is a well-known process but multiple retained primary, permanent, and supernumerary teeth that too in an asymptomatic, non-syndromic patient is a rare possibility that has rarely been reported in literature. This case report discusses the clinical and radiographic details along with treatment options in a 21-year-old patient having a total number of 50 teeth, i.e., 16 retained primary teeth, 32 permanent teeth, and 2 supernumerary teeth without being associated with any known syndrome complex or metabolic disorder. PMID:24082755

Bhatia, Vishwas; Jain, Nitul; Bhatia, Garima; Garg, Rakesh

2013-01-01

55

Dental Hygiene: How to Care for Your Child's Teeth  

MedlinePLUS

... Once your child is preschool-age, start using fluoride toothpaste. Don't cover the brush with toothpaste; ... most of the toothpaste, and swallowing too much fluoride toothpaste can cause permanent stains on their teeth. ...

56

The post-mortem pink teeth phenomenon: A case report  

Microsoft Academic Search

This study presents the case of the post-mortem pink teeth phenomenon observed during an autopsy procedure performed on the body of a man who was kidnapped and murdered approximately 30 days before the examination. The corpse was in an advanced stage of decomposition and putrefaction. Both maxillary and jaw bones were in- tact, as well as the permanent teeth which

Evelyne-Pessoa Soriano; Marcus-Vitor-Diniz de Carvalho; Francisco-Bernardo Dos Santos; Clóvis-César de Mendoza; Maria-do Socorro-Dantas de Araújo; Reginaldo-Inojosa-Carneiro Campello

57

Bilateral Supernumerary Teeth in Deciduous Dentition-A Rarity  

PubMed Central

Supernumerary teeth are considered as one of the most significant dental anomalies during the primary and early mixed dentition stages. They are of great concern to the dentists and parents because of the eruption, occlusal, and esthetic problems they can cause. Supernumerary teeth occur more frequently in the permanent dentition but rarely in primary dentition and more often seen in males. A supernumerary tooth in the primary dentition can cause ectopic or delayed eruption of permanent central incisors which will further alter occlusion and may compromise esthetics and formation of dentigerous cysts. Here we discuss a case of bilateral supernumerary teeth in deciduous dentition in a female child. PMID:24995257

Ghosh, Chiranjit; Mondal, Pradeep Kumar

2014-01-01

58

A paradigm shift in endodontic management of immature teeth: Conservation of stem cells for regeneration  

Microsoft Academic Search

Objective: This article will review the new concept of regenerative endodontics in the management of immature permanent teeth. The potential role of stem cells to regenerate immature permanent teeth after conservative treatment will be discussed. Data and sources: Two sets of data source are focused in this review: (i) the characterization of various dental stem cells discovered since 2000 and

George T.-J. Huang

59

Teething: myths and facts.  

PubMed

From grandmothers to medical professionals, everyone seems to have a list of symptoms they believe are linked to teething. During this time period of an infant's life, passive immunity due to maternal antibodies wanes and exposure to a wide variety of childhood illnesses occurs. Parental false beliefs associated with teething may interfere with the prompt diagnosis and management of a range of serious illnesses. Strong parental beliefs which are not borne out by evidence will unlikely change until professionals (most of whom are also parents) change theirs. Therefore, there is a need to know the facts and the false beliefs attributed to teething. Medical professionals need to be educated about teething to provide reasonable explanations to concerned caregivers. This article examines the signs and symptoms frequently attributed to teething and their possible alternative causes. The contemporary principles of the management of teething are discussed, including supportive care. PMID:21189758

Sood, Sankalp; Sood, Mangla

2010-01-01

60

Report of a case with 19 supernumerary teeth in a non-syndromic patient  

PubMed Central

Supernumerary teeth occur frequently in human dentition, but presence of multiple supernumerary teeth in patients without any associated syndrome or systemic disorder is a rare phenomenon. Presence of supernumerary teeth in itself is not a problem and may not require removal in all cases but in certain conditions, they may be associated with several clinical complications and require removal. Here, we present a 14 year old female who complained of non emergence of permanent teeth. Orthopantomogram initially showed presence of fifteen impacted supernumerary teeth distributed in all quadrants, but later, cone-beam computed tomography further revealed four additional teeth, totaling to nineteen supernumerary teeth. Consultation with concerned specialists ruled out any syndromes or systemic disorders which led us to the diagnosis of “non-syndromic multiple supernumerary teeth” and this probably is the highest number of supernumerary teeth reported in a single non-syndromic patient till date.

Yan, Lei; Yu, Long Wang; Bhandari, Kishor; Shan, Chang Li

2014-01-01

61

Macroscopic and microscopic changes in incinerated deciduous teeth.  

PubMed

Teeth are amongst the most resilient elements of the human skeleton and are thus often utilized in routine forensic investigation involving the identification of unknown remains. Teeth exposed to thermal stress have the potential to not only aid in identification, but also in understanding the circumstances surrounding the fire. Children are twice as likely to become victims of house fire because of an inability to safely evacuate from areas of danger. The literature demonstrates, however, that research on the effects of incineration on teeth is mostly restricted to the permanent dentition. The apparent lack of knowledge on the effects of incineration on deciduous teeth thus necessitates further research in this area. To this end, this study aimed to relate colour changes that occur post heating with fragility to aid in proper handling of samples in a forensic scenario and to determine the possibility of identifying incineration temperature based on tooth condition. Teeth are amongst the most resilient elements of the human skeleton and are thus often utilized in routine forensic investigation involving the identification of unknown remains. Teeth exposed to thermal stress have the potential to not only aid in identification, but also in understanding the circumstances surrounding the fire. Children are twice as likely to become victims of house fire because of an inability to safely evacuate from areas of danger. The literature demonstrates, however, that research on the effects of incineration on teeth is mostly restricted to the permanent dentition. The apparent lack of knowledge on the effects of incineration on deciduous teeth thus necessitates further research in this area. To this end, this study aimed to relate colour changes that occur post heating with fragility to aid in proper handling of samples in a forensic scenario and to determine the possibility of identifying incineration temperature based on tooth condition. A total of 90 deciduous teeth, extracted as a part of routine clinical treatment, were exposed to temperatures ranging from 100°C to 1100°C for 30 minutes using a laboratory Gallenkamp oven. Unheated deciduous teeth were used as controls for the project. Post-incineration the teeth were analyzed under a stereomicroscope and SEM to assess the morphological changes. A colorimetric assessment was also undertaken to evaluate colour changes due to thermal stress. It was possible to identify incineration temperature based on tooth condition when the colour changes, stereomicroscopic findings and SEM images were utilized collectively. It was concluded that thermally induced changes in primary teeth occur at lower temperatures in comparison to the permanent teeth. It was also established that post-incineration deciduous teeth are fragile and show a tendency to fragment after minimal exposure to thermal stress. PMID:22785093

Karkhanis, S; Ball, J; Franklin, D

2009-12-01

62

A Novel Technique in Restoring Fractured Anterior Teeth  

PubMed Central

Trauma to the anterior teeth is a common phenomenon in young children and in adolescents. Uncomplicated crown fracture to the permanent teeth has an intense effect not only on the patient’s appearance, but also on function and speech. This case report describes a novel technique in restoring an uncomplicated fractured maxillary anterior tooth in a young patient with direct composite, which is economical and requires less chair side time. PMID:24701546

K, Rajavardhan; Sankar, A.J. Sai; Shaik, Tanveer Ahmed; V, Naveen Kumar; K, Raj Kumar

2014-01-01

63

A novel technique in restoring fractured anterior teeth.  

PubMed

Trauma to the anterior teeth is a common phenomenon in young children and in adolescents. Uncomplicated crown fracture to the permanent teeth has an intense effect not only on the patient's appearance, but also on function and speech. This case report describes a novel technique in restoring an uncomplicated fractured maxillary anterior tooth in a young patient with direct composite, which is economical and requires less chair side time. PMID:24701546

K, Rajavardhan; Sankar, A J Sai; Shaik, Tanveer Ahmed; V, Naveen Kumar; K, Raj Kumar

2014-02-01

64

Clinical and radiographic evaluation of vital pulp therapy in open apex teeth with MTA and ZOE.  

PubMed

The purpose of this study was to report the success rate of using mineral trioxide aggregate (MTA) and zinc oxide eugenol (ZOE) as vital pulp therapy agents in immature permanent teeth with carious or traumatic pulp exposure. Subjects were children with permanent teeth requiring pulpotomy (apexogenesis) and without systemic diseases. Both ZOE and MTA treatments as pulpotomy agents showed clinical and radiographic success in immature permanent teeth. Although MTA was more successful, it is more expensive, and dentin bridges may develop over canal orifices, complicating future root canal therapy. PMID:22803275

Ghoddusi, Jamileh; Shahrami, Fatemeh; Alizadeh, Mahyareh; Kianoush, Kamyar; Forghani, Maryam

2012-04-01

65

Sequential Supernumerary Teeth Development in a Non-Syndromic Patient; Report of a Rare Case  

PubMed Central

Isolated impacted supernumerary teeth are quite rare, but they can be seen associated with several syndromes such as cleidocranial dysostosis or Gardner’s syndrome. This article aims to discuss a case of sequential formation of supernumerary teeth with no other associated disease or syndrome. A 17-year-old Iranian male with 8 impacted supernumerary teeth was referred to the department of pediatric dental clinic at Shahid Beheshti Medical University in Tehran with a history of several impacted unerupted teeth. Repeated and periodical clinical and radiographic examinations revealed newly formed teeth buds in unusual dental ages. All extra teeth were associated with generalized enamel hypoplasia to some degree on their relative permanent adjacent teeth. The patient did not have any record of a systemic disease or any syndromic condition to relate his dental problem to. This rare condition involved repeated and continued formation of extra teeth out of the normal numbers and dental age evident in serial radiographs. PMID:24910667

Jafarian, Mohammad; Nazemi, Bahareh; Bargrizan, Majid; Ramezani, Jamileh; Ansari, Ghassem

2013-01-01

66

About Kids' Teeth  

MedlinePLUS

... Learn about Preventing Kids' Tooth Decay 12 â?? 17 Years Old Cavities arenâ??t just for little ... playing sports like basketball, soccer, football and hockey. 17 â?? 21 Years Old The last teeth to ...

67

About Kids' Teeth: Nutrition  

MedlinePLUS Videos and Cool Tools

... washed away from your kidâ??s teeth by saliva, water or milk, so they have more cavity-causing ... live in a community with fluoride in the water or have the right amount of naturally occurring ...

68

Bilateral fusion of mandibular second molars with supernumerary teeth: case report  

Microsoft Academic Search

Fusion is a developmental anomaly characterized by the union of two adjacent teeth. In this article we report a rare case of bilateral fusion of permanent mandibular second molars with supernumerary teeth. The rarity with which this entity appears, along with its complex characteristics, often make it difficult to treat. The endodontic management of one tooth is described, as well

Eduardo Nunes; Ivaldo Gomes de Moraes; Paulo Márcio de Oliveira Novaes; Simone Maria Galvão de Sousa

2002-01-01

69

Use of Cantilever Mechanics for Impacted Teeth: Case Series  

PubMed Central

This paper describes the orthodontic treatment, and the biomechanics of cantilevers for the impaction of permanent teeth in youngs, adolescents, and adults. In these case series, multibracket straightwire fixed appliances, together with cantilever mechanics, were used to treat the impaired occlusion. PMID:24511332

Paduano, Sergio; Spagnuolo, Gianrico; Franzese, Gerardo; Pellegrino, Gioacchino; Valletta, Rosa; Cioffi, Iacopo

2013-01-01

70

Bleaching discoloured teeth.  

PubMed

The bleaching of teeth has encountered some legislative problems over the past few years but it is now possible to use both vital and non-vital bleaching techniques in the UK. Hydrogen peroxide has a long history of use and would appear to be safe to use to change the appearance of discoloured teeth. It is conservative of tooth tissue and may delay the need for more invasive veneers and crowns. This article describes some of the methods of bleaching using hydrogen peroxide that are currently available. PMID:11819944

Bartlett, D

2001-01-01

71

Prevalence of impacted and supernumerary teeth in the North Indian population  

PubMed Central

Objectives: Dental impaction is a very frequent problem. Supernumerary teeth, or hyperdontia, are the presence of additional teeth to the normal series in the either of the dentition. The presence of impacted and/or supernumerary teeth can cause various complications. The objective of the present study was to determine the prevalence of impacted and supernumerary teeth in the North Indian population. Study Design: The panoramic radiographic records of 4750 patients attending the Department of Oral Medicine and Radiology, Jodhpur Dental College General Hospital between September 2008 to December 2012 were examined for this retrospective study. The ages of the patients ranged from 8 to 72 years, with a mean of 34.6 years. Results: A total of 798 (16.8%) patients presented with 1126 impacted teeth. Impacted canines were the most prevalent (9.7%), followed by impacted premolars (4.3%). Supernumerary teeth (1.6%) and impacted molars (1.2%) were less prevalent. Among the 842 impacted teeth, the most frequently affected teeth were the canines (56.7%), followed by premolars (27.8%), and supernumerary teeth (9.3%), while the prevalence of impacted molars was quite lower (6.2%). Conclusion: The most frequently impacted teeth were maxillary canines and the mesiodens were the most common supernumerary tooth. The early diagnosis of supernumerary and impacted teeth is essential to prevent malocclusion and malalignment of permanent teeth demonstrating the importance of panoramic radiographs in their detection. Key words:Impacted, supernumerary, prevalence, canines, mesiodens. PMID:24790709

Maheshwari, Sneha

2014-01-01

72

Initiation of teeth from the dental lamina in the ferret.  

PubMed

Mammalian tooth development is characterized by formation of primary teeth that belong to different tooth classes and are later replaced by a single set of permanent teeth. The first primary teeth are initiated from the primary dental lamina, and the replacement teeth from the successional dental lamina at the lingual side of the primary teeth. An interdental lamina connects the primary tooth germs together. Most mammalian tooth development research is done on mouse, which does not have teeth in all tooth classes, does not replace its teeth, and does not develop an interdental lamina. We have used the ferret (Mustela putorius furo) as a model animal to elucidate the morphological changes and gene expression during the development of the interdental lamina and the initiation of primary teeth. In addition we have analyzed cell-cell signaling taking place in the interdental lamina as well as in the successional lamina during tooth replacement. By 3D reconstructions of serial histological sections we observed that the morphogenesis of the interdental lamina and the primary teeth are intimately linked. Expression of Pitx2 and Foxi3 in the interdental lamina indicates that it has odontogenic identity, and there is active signaling taking place in the interdental lamina. Bmp4 is coexpressed with the stem cell factor Sox2 at its lingual aspect suggesting that the interdental lamina may retain competence for tooth initiation. We show that when tooth replacement is initiated there is Wnt pathway activity in the budding successional lamina and adjacent mesenchyme but no active Fgf or Eda signaling. Genes associated with human tooth replacement phenotypes, including Runx2 and Il11r?, are mostly expressed in the mesenchyme around the successional lamina in the ferret. Our results highlight the importance of the dental lamina in the mammalian tooth development during the initiation of both primary and replacement teeth. PMID:24393477

Jussila, Maria; Crespo Yanez, Xenia; Thesleff, Irma

2014-01-01

73

The post-mortem pink teeth phenomenon: a case report.  

PubMed

This study presents the case of the post-mortem pink teeth phenomenon observed during an autopsy procedure performed on the body of a man who was kidnapped and murdered approximately 30 days before the examination. The corpse was in an advanced stage of decomposition and putrefaction. Both maxillary and jaw bones were intact, as well as the permanent teeth which presented the "pink teeth phenomenon", probably due to a haemorrhage in the pulp chambers. The pink discolouration was most pronounced at the neck of the teeth. The cause of death was asphyxia. Although the examiners stressed that post-mortem pink teeth must not be considered as a reliable odontological parameter for determining the cause of death, the results of other studies have shown that the pink teeth phenomenon is a common finding related to cases of asphyxia such as strangulation, drowning or suffocation. Thus, the pink teeth phenomenon must be studied in order to determine its role as a post-mortem finding. As of now, an exact relationship between the cause of death and this phenomenon remains unknown. PMID:19300367

Soriano, Evelyne-Pessoa; Carvalho, Marcus-Vitor-Diniz de; Santos, Francisco-Bernardo Dos; Mendoza, Clóvis-César de; Araújo, Maria-do Socorro-Dantas de; Campello, Reginaldo-Inojosa-Carneiro

2009-07-01

74

Wear of sheep's Teeth  

Microsoft Academic Search

Length of incisor teeth of four-tooth ewes (stocked seven per acre), and soil content of faeces, were measured every six weeks from February 1965 to January 1966 at the Te Awa hill country research area of the Grasslands Division, Department of Scientific and Industrial Research. Wear was low when soil content of faeces was low, and rose to a peak

T. G. Ludwig; W. B. Healy; T. W. Cutress

1966-01-01

75

Types of Teeth  

MedlinePLUS

... jaw, all premolars have one root. Molars — The last three upper and lower teeth on both sides of ... food. On the upper jaw, the molars have three well-separated roots. On the lower jaw, the molars have two roots. Last updated September 26, 2013 © 2002-2014 Aetna, Inc. ...

76

Diastema (Gap between Teeth)  

MedlinePLUS

... If a frenectomy is done in a younger child, the space may close on its own. If it is ... To Call a Professional If you have a space between your teeth or see one in your child's mouth, talk with your dentist. He or she ...

77

Taking Care of Your Teeth  

MedlinePLUS

... re choosing a toothpaste, make sure it contains fluoride . Fluoride makes your teeth strong and protects them from ... Dentist Bad Breath What's a Cavity? How Does Fluoride Work? Your Teeth Taking the Bite Out of ...

78

Remarkable resilience of teeth  

PubMed Central

Tooth enamel is inherently weak, with fracture toughness comparable with glass, yet it is remarkably resilient, surviving millions of functional contacts over a lifetime. We propose a microstructural mechanism of damage resistance, based on observations from ex situ loading of human and sea otter molars (teeth with strikingly similar structural features). Section views of the enamel implicate tufts, hypomineralized crack-like defects at the enamel–dentin junction, as primary fracture sources. We report a stabilization in the evolution of these defects, by “stress shielding” from neighbors, by inhibition of ensuing crack extension from prism interweaving (decussation), and by self-healing. These factors, coupled with the capacity of the tooth configuration to limit the generation of tensile stresses in largely compressive biting, explain how teeth may absorb considerable damage over time without catastrophic failure, an outcome with strong implications concerning the adaptation of animal species to diet. PMID:19365079

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

2009-01-01

79

Periapical status of root-filled teeth in Norwegian children and adolescents.  

PubMed

Abstract Objective. To study the periapical status of root-filled permanent teeth of 9-17-year-olds in Møre & Romsdal county, Norway. Materials and methods. All permanent teeth with endodontic treatment in patients born in 1994-2001 were identified in the dental records of the Public Dental Service. The data collected consisted of chart entries and radiographs. Of 1182 teeth, 174 teeth in 155 patients met further inclusion criteria, i.e. completed endodontic treatment and a follow-up with a readable radiograph of at least 1 year. Periapical status was assessed with the Periapical Index (PAI) and the technical quality of the root fillings was also quantified on a 4-grade visual scale. Results. Apical periodontitis was found on follow-up radiographs in 25% of all teeth and in 48% of the teeth with pre-operative apical periodontitis. Forty-two per cent of root fillings were of adequate technical quality. Adequate technical quality of the root filling was significantly correlated with radiographic success. Conclusions. About one fourth of all root-filled teeth and almost half of the teeth with pre-operative apical periodontitis showed clear signs of the disease at recall. PMID:24931925

Jordal, Kristin; Valen, Anthony; Orstavik, Dag

2014-11-01

80

Accuracy of age estimation of radiographic methods using developing teeth.  

PubMed

Developing teeth are used to assess maturity and estimate age in a number of disciplines, however the accuracy of different methods has not been systematically investigated. The aim of this study was to determine the accuracy of several methods. Tooth formation was assessed from radiographs of healthy children attending a dental teaching hospital. The sample was 946 children (491 boys, 455 girls, aged 3-16.99 years) with similar number of children from Bangladeshi and British Caucasian ethnic origin. Panoramic radiographs were examined and seven mandibular teeth staged according to Demirjian's dental maturity scale [A. Demirjian, Dental development, CD-ROM, Silver Platter Education, University of Montreal, Montreal, 1993-1994; A. Demirjian, H. Goldstein, J.M. Tanner, A new system of dental age assessment, Hum. Biol. 45 (1973) 211-227; A. Demirjian, H. Goldstein, New systems for dental maturity based on seven and four teeth, Ann. Hum. Biol. 3 (1976) 411-421], Nolla [C.M. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266] and Haavikko [K. Haavikko, The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study. Proc. Finn. Dent. Soc. 66 (1970) 103-170]. Dental age was calculated for each method, including an adaptation of Demirjian's method with updated scoring [G. Willems, A. Van Olmen, B. Spiessens, C. Carels, Dental age estimation in Belgian children: Demirjian's technique revisited, J. Forensic Sci. 46 (2001) 893-895]. The mean difference (+/-S.D. in years) between dental and real age was calculated for each method and in the case of Haavikko, each tooth type; and tested using t-test. Mean difference was also calculated for the age group 3-13.99 years for Haavikko (mean and individual teeth). Results show that the most accurate method was by Willems [G. Willems, A. Van Olmen, B. Spiessens, C. Carels, Dental age estimation in Belgian children: Demirjian's technique revisited, J. Forensic Sci. 46 (2001) 893-895] (boys -0.05+/-0.81, girls -0.20+/-0.89, both -0.12 y+/-0.85), Demirjian [A. Demirjian, Dental development, CD-ROM, Silver Platter Education, University of Montreal, Montreal, 1993-1994] overestimated age (boys 0.25+/-0.84, girls 0.23+/-0.84, both 0.24 y+/-0.86), while Nolla [C.M. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266] and Haavikko's [K. Haavikko, The formation and the alveolar and clinical eruption of the permanent teeth. An orthopantomographic study, Proc. Finn. Dent. Soc. 66 (1970) 103-170] methods under-estimated age (boys -0.87+/-0.87, girls -1.18+/-0.96, both -1.02 y+/-0.93; boys -0.56+/-0.91, girls -0.79+/-1.11, both -0.67 y+/-1.01, respectively). For individual teeth using Haavikko's method, first premolar and second molar were most accurate; and more accurate than the mean value of all developing teeth. The 95% confidence interval of the mean was least for mean of all developing teeth using Haavikko (age 3-13.99 years), followed by identical values for Demirjian and Willems (sexes combined). PMID:16533584

Maber, M; Liversidge, H M; Hector, M P

2006-05-15

81

Dental erosion in deciduous teeth—an in vivo and in vitro study  

Microsoft Academic Search

Objective: The aims of this study were to report on severe dental erosion and its associated etiological factors in deciduous teeth of Saudi children (n=16, X?=6.5 years, R=5–8) in vivo, and to confirm (or reject) the clinical diagnosis by scanning electron microscopy (SEM). Another aim was to study progression of erosion in vitro using extracted healthy deciduous and permanent teeth.Method:

A.-K. Johansson; R. Sorvari; D. Birkhed; J. H. Meurman

2001-01-01

82

Mineral minimization in nature's alternative teeth  

E-print Network

REVIEW Mineral minimization in nature's alternative teeth Christopher C. Broomell1, , Rashda K, particularly teeth, have been extensively studied in structural, chemical, mechanical and clinical detail

Zok, Frank

83

The effects of periradicular inflamation and infection on a primary tooth and permanent successor.  

PubMed

Primary teeth and the permanent successors must be understood as interdependent units, where each one of them interacts with and depends on each other. Pulpal inflammation/infection of a primary tooth and the spread of this condition over the periradicular tissues can lead to alterations in the dental germ of the permanent successor and to the surrounding structures if no therapy is done, i.e. endodontics or extraction. This work will present cases of permanent teeth that showed alteration in eruption and / or in development, as a consequence of inflammation / infection of the preceding primary teeth, such as: hypoplasia, morphological alteration on the dental crown or total arrest of. radicular formation. The teeth analysed in this study belong to patients who attended the Universidade Federal de Santa Catarina Children's Dentistry Clinic. The earlier these lesions are diagnosed, the less were the destructive effects and the consequences on the primary tooth/permanent germ unit. PMID:15926433

Cordeiro, Mabel Mariela Rodriguez; Rocha, Maria Jose de Carvalho

2005-01-01

84

Periodontal Ligament Stem Cells Modulate Root Resorption of Human Primary Teeth via Runx2 Regulating RANKL/OPG System.  

PubMed

Physiological primary teeth exfoliation is a normal phenomenon during teeth development. However, retained primary teeth can often be observed in the patients with cleidocranial dysplasia (CCD) caused by mutation of Runx2. The potential regulative mechanism is still unknown. In the present study, periodontal ligament stem cells (PDLSCs) were derived from different resorbed stages of primary teeth and permanent teeth from normal patients and primary teeth from CCD patient. The proliferative, osteogenic and osteoclast-inductive capacities of PDLSCs from each group were detected. We demonstrated here that the proliferative ability of PDLSCs was reduced while the osteogenic and the osteoclast-inductive capacity of PDLSCs were enhanced during root resorption. The results also showed that PDLSCs from permanent teeth and CCD patient expressed low level of Runx2 and RANKL while high level of OPG. However, expression of Runx2 and RANKL were increased while expression of OPG was decreased in PDLSCs derived from resorbed teeth. Furthermore, Runx2 regulating the expression of RANKL and OPG and the osteoclast-inductive capacity of PDLSCs were confirmed by gain or loss of function assay. These data suggest that PDLSCs promote osteoclast differentiation via Runx2 upregulating RANKL and downregulating OPG, leading to enhanced root resorption that results in physiological exfoliation of primary teeth. PMID:24827498

Li, Bei; Zhang, Yu; Wang, Qingchao; Dong, Zhiwei; Shang, Linjuan; Wu, Lizheng; Wang, Xiaojing; Jin, Yan

2014-10-15

85

Clinical management of discolored teeth.  

PubMed

Discolored teeth are seen frequently in the dental office and present a major challenge to dentists. Discoloration may be limited to a single tooth or several teeth in a single arch or it may be generalized and evident on all of the teeth. It is essential to recognize the cause and to manage the discoloration accordingly. Generally, dentists' intervention is essential for treating substantial tooth discoloration. In some cases, scaling and polishing the teeth will improve the situation; however, more extensive treatment often is needed to achieve a satisfying result. Treatment options include vital and non-vital bleaching, microabrasion, composite and porcelain veneers, and porcelain crowns. Sometimes these treatments are combined for a more successful outcome. PMID:19288841

Setien, Victor J; Roshan, Susan; Nelson, Paul W

2008-05-01

86

Jaws and Teeth of Mammals  

NSDL National Science Digital Library

This image from Biology by Kenneth R. Miller and Joseph Levine illustrates the relationship between structure and function by comparing the jaws and teeth of two animals with very different ways of life: the wolf and the horse.

2007-12-12

87

Keeping Your Child's Teeth Healthy  

MedlinePLUS

... other problems, the dentist may start applying topical fluoride even before all teeth come in (this also can be done in the pediatrician's office). Fluoride hardens the tooth enamel, helping to ward off ...

88

Do Fluoride Ions Protect Teeth?  

ERIC Educational Resources Information Center

Begins with the procedure and results from an investigation on the effect of fluoride on the reaction between eggshell (substitute teeth) and dilute ethanoic acid. Describes an elegantly modified and improvised apparatus. (DDR)

Parkin, Christopher

1998-01-01

89

Taking Care of Your Teeth  

MedlinePLUS

... gumline. Gently brush from where the tooth and gum meet to the chewing surface in short (about half-a-tooth-wide) strokes. Brushing too hard can cause receding gums, tooth sensitivity, and, over time, loose teeth. Use ...

90

Concentration of {sup 226}Ra in human teeth  

SciTech Connect

{sup 226}Ra concentrations in human teeth from several cities, mainly Tokyo, Japan, were determined with emphasis on the measurement of low-level {sup 226}Ra by alpha-ray spectrometry following chemical separation. No appreciable differences in {sup 226}Ra concentration were found among various permanent teeth samples of different age groups in Tokyo. The mean {sup 226}Ra concentration for Tokyo was 0.51 {+-} 0.06 mBq (g CA){sup -1}. {sup 226}Ra concentration [mean: 0.67 {+-} 0.11 mBq (g Ca){sup -1}] in teeth in western regions of the country was statistically higher than that [mean: 0.48 {+-} 0.09 mBq (g Ca){sup -1}] in eastern ones. The mean {sup 226}Ra concentration [0.51 mBq (g CA){sup -1}] in teeth from Tokyo was less than the concentration [1.11 mBq (g CA){sup -1}] reported for vertebral bone samples of this city. 27 refs., 1 fig., 5 tabs.

Yamamoto, Masayoishi; Ueno, Kaoru [Kanazawa Univ., Tatsunokuchi (Japan); Hinoide, Moriyo [National Institute of Health, Shinjuku (Japan); Ohkubo, Yoshiteru [Fukui Prefectural Institute of Public Health (Japan)

1994-11-01

91

Application to Forensic Odontology of Aspartic Acid Racemization in Unerupted and Supernumerary Teeth  

Microsoft Academic Search

Racemization of aspartic acid in dentin protein during the human lifetime progresses with age. The extent of racemization of aspartic acid in coronal dentin of normal permanent teeth can be used in forensic odontology to estimate the age of an individual at the time of death (Ogino et al., 1985). A series of experiments was conducted with dentin separated from

T. Ogino; H. Ogino

1988-01-01

92

3 Dimensional Diagnosis Unravelling Prognosis of Multiple Impacted Teeth - A Case Report  

PubMed Central

Impaction of teeth results from the interplay between nature and nurture. Radiographs play an important role in assessment of both the location and the typing of impacted teeth. In general, periapical, occlusal, and/or panoramic radiographs are sufficient for providing the information required by the clinician. Recent advances in diagnostic imaging enables to visualize , diagnose and prognose the treatment outcome of the impacted teeth. This case report discusses the value of cone beam computerized tomography (CBCT) for evaluation of the critical parameters like bone thickness , tooth position and tooth morphology of multiple impacted teeth by 3 dimensional radiography – CBCT. In this report, we present a case of 27-year-old male patient with multiple missing teeth. Radiographs revealed multiple impacted permanent teeth, though medical and family history along with physical examination was not suggestive of any syndromes. Intraoral periapical radiograph, Orthopantomograph, Occlusal radiograph, Cone beam computed tomography were taken for the same patient to determine the exact position of multiple impacted teeth and prognose the treatment plan with the associated factors to impacted teeth. Cone beam computed tomography is an accurate modality to localize and determine the prognosing factors associated with multiple impacted teeth. Three-dimensional volumetric imaging might provide information for improved diagnosis and treatment plans, and ultimately result in more successful treatment outcomes and better care for patients. How to cite this article: Gopinath A, Reddy NA, Rohra MG. 3 Dimensional Diagnosis Unravelling Prognosis of Multiple Impacted Teeth – A Case Report. J Int Oral Health 2013; 5(4):78-83. PMID:24155625

Gopinath, Adusumilli; Reddy, Naveen Admala; Rohra, Mayur G

2013-01-01

93

The Economic Value of Teeth  

Microsoft Academic Search

Healthy teeth are a vital and visible component of general well-being, but there is little systematic evidence to demonstrate their economic value. In this paper, we examine one element of that value, the effect of oral health on labor market outcomes, by exploiting variation in access to fluoridated water during childhood. The politics surrounding the adoption of water fluoridation by

Sherry Glied; Matthew Neidell

2008-01-01

94

Evolution and development of teeth  

PubMed Central

Teeth as a feeding mechanism in an oral cavity (mouth) are functionally and locationally linked with jaws. In fossils, teeth found in the oral cavity are usually linked with jaws, although mineralised structures with the same histology as teeth are known in fossils before jaws appeared. Denticles in the skin occur in both fossil and extant fish. Pharyngeal denticles also occur in both extant and fossil gnathostomes but in only a few fossil agnathans (thelodonts). Complex structures with dentine and enamel have been described in the earliest jawless vertebrates, conodonts. Such fossils have been used to suggest that teeth and jaws have evolved and developed independently. Our understanding of the developmental biology of mammalian tooth development has increased greatly in the last few years to a point where we now understand some of the basic genetic interactions controlling tooth initiation, morphogenesis and patterning. The aim of this review is to see what this developmental information can reveal about evolution of the dentition. PMID:11523817

McCOLLUM, MELANIE; SHARPE, PAUL T.

2001-01-01

95

Nanoindentation and storage of teeth  

Microsoft Academic Search

This study determined changes in nanomechanical properties of dentin and enamel during storage in deionized water, calcium chloride buffered saline solution and Hank's balanced salts solution (HBSS). Atomic force microscopy based nanoindentation showed that storing teeth in deionized water or CaCl2-solution resulted in a large decrease in elastic modulus and hardness. At 1 day a decrease in the mechanical properties

Stefan Habelitz; Grayson W. Marshall Jr.; Mehdi Balooch; Sally J. Marshall

2002-01-01

96

A Talon Cusp on Fused Teeth Associated with Hypodontia: Report of a Unique Case  

PubMed Central

Fusion and talon cusps are rare developmental dental anomalies affecting both primary and permanent dentitions. Talon cusps normally occur on the palatal surface of permanent maxillary incisors, while fused teeth are more common in the primary anterior dentition. An understanding of these dental anomalies and their associated problems are important to provide prophylactic measures, thereby preventing or minimizing possible complications. This paper presents a unique case of fused mandibular permanent incisors with a lingual talon cusp associated with hypodontia of an adjacent tooth. PMID:20046484

Dinesh Rao, B; Hegde, Sapna

2010-01-01

97

Take Care of Your Teeth and Gums  

MedlinePLUS

... Brush your teeth 2 times a day with fluoride (“FLOOR-ide”) toothpaste. Floss between your teeth every ... day. Use a toothbrush with soft bristles and fluoride toothpaste. Fluoride is a mineral that helps protect ...

98

Take Care of Your Child's Teeth  

MedlinePLUS

... times a day. Protect your child’s teeth with fluoride (“FLOOR-ide”). Give your child healthy, low-sugar ... a day. Start brushing your child’s teeth with fluoride toothpaste at age 2 (or sooner if a ...

99

[Progress in the treatment of stained teeth].  

PubMed

The treatment of stained teeth has been one of the striking aspects of stomatology and esthetic dentistry. Based on detailed data and references, this article introduces the types of stained teeth and the main treatment methods including strong point, weakness, limitation of the usage, result, and the relevant mechanisms. It addresses the researches on problems in the treatment of stained teeth. Also in this paper is envisaged what will be done to treat the stained teeth in future. PMID:15250169

Huo, Danqun; Xie, Guo; Hou, Changjun; Liu, Jia; Huang, Chunyue; He, Zuoyun

2004-06-01

100

NATURAL VARIATION IN SPOTTING, HYOID TEETH COUNTS,  

E-print Network

^i^^- fV/ NATURAL VARIATION IN SPOTTING, HYOID TEETH COUNTS, AND COLORATION OF YELLOWSTONE and Wildlife, Daniel H. Janzen, Director NATURAL VARIATION IN SPOTTING, HYOID TEETH COUNTS, AND COLORATION cited 10 Appendix ,, 11 #12;#12;NATURAL VARIATION IN SPOTTING, HYOID TEETH COUNTS, AND COLORATION

101

TeethClick: Input with Teeth Clacks Tamer Mohamed Lin Zhong  

E-print Network

TeethClick: Input with Teeth Clacks Tamer Mohamed Lin Zhong Dept. of Electrical & Computer Engineering Rice University, Houston, TX 77005 {lzhong}@rice.edu ABSTRACT We present TeethClick, a simple yet robust input technique based on automatic detection of teeth clacks with a throat microphone. We address

Zhong, Lin

102

Animation, Teeth and Skeletons ... (using Discrete Differential Geometry!)  

E-print Network

Animation, Teeth and Skeletons ... (using Discrete Differential Geometry!) June 7, 2010 Teeth, Skeletons, Animation #12;Animation Teeth, Skeletons, Animation #12;Animation 3-dimensional Animation relies on computer graphics Teeth, Skeletons, Animation #12;Animation 3-dimensional Animation relies on computer

Rauhut, Holger

103

Iron deposition in modern and archaeological teeth  

NASA Astrophysics Data System (ADS)

Iron surface concentrations and profile maps were measured on the enamel of archaeological and modern teeth to determine how iron is deposited in tooth enamel and if it was affected by the post-mortem environment. Teeth from Australian children who died in the second half of the 19th century were compared with contemporary teeth extracted for orthodontic purposes. Surface analysis of the teeth was performed using the 3 MV Van Der Graff Accelerator at The Australian Nuclear Science and Technology Organisation (ANSTO), Sydney, Australia. A small sample of teeth were then cut in the mid sagittal plane and analysed using ANSTO High Energy Heavy Ion Microprobe. Maps and linear profiles were produced showing the distribution of iron across the enamel. Results show that both the levels and distribution of iron in archaeological teeth is quite different to contemporary teeth, raising the suggestion that iron has been significantly altered by the post-mortem environment.

Williams, A.-M. M.; Siegele, R.

2014-09-01

104

Essure Permanent Birth Control  

MedlinePLUS

... Spinal Fluid (CSF) Shunt Systems Essure Permanent Birth Control Benefits of Essure FDA’s Review of Reported Problems ... Essure Additional Information Essure is a permanent birth control method for women that creates a barrier against ...

105

Comparative Evaluation of Impact Strength of Fragment Bonded Teeth and Intact Teeth: An In Vitro Study  

PubMed Central

Background: To test and compare the impact strength of fragment bonded teeth with that of intact teeth by using impact testing machine (pendulum type) as a mode of load. Materials and Methods: Forty extracted, maxillary, central incisors selected for this study (20 control group and 20 experimental group). In experimental group, teeth crowns were fractured with a microtome at 2.5 mm from mesioincisal angle cervically, fractured portion is attached to original crown portion with 3 M single bond dentin bonding agent and 3 M Z ‘100’, composite resin. Impact strength of fragment bonded teeth and intact teeth tested with impact testing machine and compared. Results: Mean impact strength of fragment bonded teeth (30.76 KJ/M2 ) is not statistically significant deferent from mean impact strength of intact teeth (31.11 KJ/M2 ). Conclusion: Mean impact strength of fragment bonded teeth is not statistically different with that of intact teeth. Hence, after fracture of teeth if it is restored with fragment reattachment by using 3 M single bond dentin bonding agent and 3 M Z ‘100’ composite resin is having impact strength like that of intact teeth. How to cite the article: Venugopal L, Lakshmi MN, Babu DA, Kiran VR. Comparative evaluation of impact strength of fragment bonded teeth and intact teeth: An in vitro study. J Int Oral Health 2014;6(3):73-6. PMID:25083037

Venugopal, L; Lakshmi, M Narasimha; Babu, Devatha Ashok; Kiran, V Ravi

2014-01-01

106

Supernumerary teeth in non-syndromic patients.  

PubMed

Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized. PMID:22474647

Mali, Santosh; Karjodkar, Freny Rashmiraj; Sontakke, Subodh; Sansare, Kaustubh

2012-03-01

107

Study of teeth phosphorescence detection technique  

NASA Astrophysics Data System (ADS)

On the basis of research and analysis into optical properties of teeth, this paper introduces the techniques to transform teeth phosphorescence excited by ultraviolet light into electric signals and following steps for data collection, analysis and processing. Also presented are the methods to diagnose pulp-vitality, decayed teeth, and, especially, infant caries and pre-caries diseases. By measurement of a tooth's temperature, other stomatic illnesses can be diagnosed.

Cai, De-Fang; Wang, Shui-ping; Yang, Zhen-jiang; An, Yuying; Huang, Li-Zi; Liang, Yan

1995-05-01

108

A coding solution for supernumerary teeth.  

PubMed

In South Africa payments for treatment rendered are routinely delayed because of the medical fund industry's apparent inability to capture codes denoting supernumerary teeth. The suggested protocol allows for up to 13 supernumerary teeth to be identified by two digits. Meetings planned between SADA and key funding stakeholders to "ensure that protocols related to tooth numbering are acceptable", provide the ideal opportunity to introduce the suggested two-digit protocol for numbering supernumerary teeth. If this proposal is implemented, it could alleviate the frustration associated with the rejection of accounts where supernumerary teeth are appropriately identified. PMID:23198467

van der Westhuijzen, A J; Morkel, J A

2011-08-01

109

Tooth Sensitivity in Fluorotic Teeth  

PubMed Central

Objectives: The aim of this study was to compare the demographic and clinical features of tooth sensitivity (TS) in subjects with and without fluorosis. Methods: A total of 2249 subjects (378 subjects with fluorosis and 1871 subjects without fluorosis) were examined for TS during a study period of one year and TS was determined in 122 subjects. The level of TS was evaluated on a visual analogue scale (VAS). The sensitivity evaluation was made by applying tactile and cold air stimuli. In teeth sensitive to any stimuli, the plaque index (PI), gingival index (GI), gingival recession (GR) and periodontal pocket depth (PPD) were recorded. Fluorosis was assessed using the Dean Index. Results: One hundred and twenty-two participants were found to have TS (5.42%). The frequency of TS in subjects with fluorosis was 9.26%, while the frequency of TS in subjects without fluorosis was 4.65%. There was a statistically significant difference between the groups in terms of TS frequency (P=0.0003). In contrast, there were no significant differences between the groups for periodontal parameters except PI. Conclusions: The results of the study showed that the subjects with fluorosis may have been suffering from TS more than the subjects with normal dentition. Further studies are necessary to determine the factors that contribute to sensitivity of teeth with fluorosis. PMID:21769268

Tonguc, Mine Ozturk; Ozat, Yener; Sert, Tugba; Sonmez, Yonca; Kirzioglu, F. Yesim

2011-01-01

110

Comparative Evaluation of Endodontic Management of Teeth With Unformed Apices With Mineral Trioxide Aggregate and Calcium Hydroxide  

Microsoft Academic Search

Purpose: The purpose of this study was to compare mineral trioxide aggregate (MTA) and calcium hydroxide (Ca(OH)2) for their efficacies and time taken for formation of apical biological calcific barriers and resolution of periapical radiolucencies, if present at baseline, in teeth with unformed apices. Methods: Twenty nonvital permanent maxillary incisors with unformed apices, stratified according to the size of periapical

D. P. Pradhan; H. S. Chawla; K. Gauba; A. Goyal

111

Rare earth permanent magnets  

Microsoft Academic Search

Permanent magnets were discovered centuries ago from what was known as {open_quotes}lodestone{close_quotes}, a rock containing large quantities of the iron-bearing mineral magnetite (FeâOâ). The compass was the first technological use for permanent magnetic materials; it was used extensively for navigational purposes by the fifteenth century. During the twentieth century, as new applications for permanent magnets were developed, interest and research

Major-Sosias

1993-01-01

112

Electrical Conductance of Fissure Enamel in Recently Erupted Molar Teeth as Related to Caries Status  

Microsoft Academic Search

Pit-and-fissure caries lesions contribute greatly to the caries incidence in permanent molar teeth in children. To date, the diagnosis of occlusal caries is still performed mainly by visual inspection, periodically aided by bite-wing radiography. However, in detecting small occlusal carious lesions, these methods perform inadequately, especially in low caries prevalence populations or individuals. The use of electrical conductance measurements (ECMs)

Y. L. Ie; E. H. A. M. Verdonschot; M. J. M. Schaeken; M. A. van’t Hof

1995-01-01

113

Glycosaminoglycans of the odontoblast-predentine layer in dentinogenically active porcine teeth  

Microsoft Academic Search

The glycosaminoglycans (GAGs) in the odontoblast-predentine layer, dissected out from dentinogenically active permanent porcine teeth, have been isolated and analyzed with the following results. 1. Light and electron microscopy indicated that odontoblasts and predentine were present in roughly equal amounts. 2. The total hexosamines accounted for 0.84 ?g\\/mg tissue wet weight (2.9 ?g\\/mg dry weight). 3. Cellulose acetate membrane electrophoresis

Anders Linde

1973-01-01

114

Drug-induced Disorders of Teeth  

Microsoft Academic Search

It is essential that every health care professional who is involved with the prescription or recommendation of drugs be fully aware of any resultant disorders that may arise as a side-effect. A range of drugs can affect the teeth. In this review article, drugs that have the potential to induce changes in teeth have been classified as those leading to

C. J. Tredwin; C. Scully; J.-V. Bagan-Sebastian

2005-01-01

115

Dual epithelial origin of vertebrate oral teeth  

Microsoft Academic Search

The oral cavity of vertebrates is generally thought to arise as an ectodermal invagination. Consistent with this, oral teeth are proposed to arise exclusively from ectoderm, contributing to tooth enamel epithelium, and from neural crest derived mesenchyme, contributing to dentin and pulp. Yet in many vertebrate groups, teeth are not restricted only to the oral cavity, but extend posteriorly as

Vladimír Soukup; Hans-Henning Epperlein; Ivan Horácek; Robert Cerny

2008-01-01

116

Disinfection of Human Teeth for Educational Purposes.  

ERIC Educational Resources Information Center

A study investigated the efficacy of glutaraldehyde and several other disinfectants for disinfecting teeth to be used for teaching and research, as an alternative to autoclaving for teeth with amalgam restorations. Results indicate that formalin was the only disinfectant that penetrated tooth pulp chambers in effective antimicrobial…

Tate, William H.; White, Robert S.

1991-01-01

117

Laser and LED external teeth-bleaching  

Microsoft Academic Search

Teeth-bleaching is an initial phase in the reproduction of an aesthetic smile; thus, it is very important that the dentist knows how to diagnose the causes of color changes and indicate whitening before proposing dental treatment. Technological advances in teeth-whitening lead to the development of new techniques, improving comfort, security and decreasing time of execution: argon laser, diode Laser, LED

Fatima A. Zanin; Aldo Brugnera Jr.; Melissa A. Marchesan; Jesus D. Pecora

2004-01-01

118

Laser and LED external teeth-bleaching  

Microsoft Academic Search

Teeth-bleaching is an initial phase in the reproduction of an aesthetic smile; thus, it is very important that the dentist knows how to diagnose the causes of color changes and indicate whitening before proposing dental treatment. Technological advances in teeth-whitening lead to the development of new techniques, improving comfort, security and decreasing time of execution: argon laser, diode laser, LED

Fatima Zanin; Aldo Brugnera Jr.; Melissa A. Marchesan; Jesus D. Pecora

2004-01-01

119

Fracture susceptibility of worn teeth.  

PubMed

An experimental simulation study is made to determine the effects of occlusal wear on the capacity of teeth to resist fracture. Tests are carried out on model dome structures, using glass shells to represent enamel and epoxy filler to represent dentin. The top of the domes are ground and polished to produce flat surfaces of prescribed depths relative to shell thickness. The worn surfaces are then loaded axially with a hard sphere, or a hard or soft flat indenter, to represent extremes of food contacts. The loads required to drive longitudinal cracks around the side walls of the enamel to failure are measured as a function of relative wear depth. It is shown that increased wear can inhibit or enhance load-bearing capacity, depending on the nature of the contact. The results are discussed in the context of biological evolutionary pressures. PMID:22100100

Keown, Amanda J; Bush, Mark B; Ford, Chris; Lee, James J-W; Constantino, Paul J; Lawn, Brian R

2012-01-01

120

Microtensile bond strength of resin composite to dentin treated with Er:YAG laser of bleached teeth  

Microsoft Academic Search

The objective of this study was to evaluate the influence of Er:YAG laser (??=?2.94 ?m) on microtensile bond strength (?TBS)\\u000a and superficial morphology of bovine dentin bleached with 16% carbamide peroxide. Forty bovine teeth blocks (7 × 3 × 3 mm3) were randomly assigned to four groups: G1- bleaching and Er:YAG irradiation with energy density of 25.56 J\\/cm2 (focused mode); G2 - bleaching; G3 - no-bleaching and

Eduardo dos Santos Leonetti; José Augusto Rodrigues; André Figueiredo Reis; Ricardo Scarparo Navarro; Ana Cecília Correa Aranha; Alessandra Cassoni

121

Banking stem cells from human exfoliated deciduous teeth (SHED): saving for the future.  

PubMed

Tooth derived cells are readily accessible and provide an easy and minimally invasive way to obtain and store stem cells for future use. Banking ones own tooth-derived stem cells is a reasonable and simple alternative to harvesting stem cells from other tissues. Obtaining stem cells from human exfoliated deciduous teeth (SHED) is simple and convenient, with little or no trauma. Every child loses primary teeth, which creates the perfect opportunity to recover and store this convenient source of stem cells--should they be needed to treat future injuries or ailments and presents a far better alternative to simply discarding the teeth or storing them as mementos from the past. Furthermore, using ones own stem cells poses few, if any, risks for developing immune reactions or rejection following transplantation and also eliminates the potential of contracting disease from donor cells. Stem cells can also be recovered from developing wisdom teeth and permanent teeth. Individuals have different opportunities at different stages of their life to bank these valuable cells. It is best to recover stem cells when a child is young and healthy and the cells are strong and proliferative. The purpose of this review is to discuss the present scenario as well as the technical details of tooth banking as related to SHED cells. PMID:19725233

Arora, Vipin; Arora, Pooja; Munshi, A K

2009-01-01

122

Morphological changes in development of pharyngeal teeth in Mylopharyngodon piceus  

NASA Astrophysics Data System (ADS)

Adult pharyngeal teeth in Mylopharyngodon piceus are molariform. Based on SEM observations of the developing teeth, this paper describes the morphological diversification of pharyngeal teeth in M. piceus. The larval and juvenile teeth are changed from conical to adult molariform teeth through seven stages. Comparisons are made between each stage and corresponding types in some species of different subfamilies in Cyprinidae. It is considered that the ontogenetic resemblances of the pharyngeal teeth bear relationship to the phylogeny of cyprinids.

Nakajima, Tsuneo; Yue, Pei-Qi

1995-09-01

123

Rare earth permanent magnets  

Microsoft Academic Search

A survey is given of the state of the art in rare earth permanent magnet research of materials based on Nd2Fe14B. The magnetic properties of various types of interstitially modified Fe-rich rare earth intermetallics are discussed, including the possibility to apply these materials in permanent magnets.

K. H. J. Buschow; F. H. Feijen; Kees de Kort

1995-01-01

124

Infrared Spectroscopic Identification of Chosen Dental Materials and Natural Teeth  

NASA Astrophysics Data System (ADS)

Studies using solid phase infrared spectroscopy in the range of 400 to 4000 wave numbers were conducted in order to quickly identify solid tooth fragments and differentiate them from dental materials used in the dental practice. The frequently employed dental materials were evaluated. Natural chemical structure of permanent teeth obtained from donors of various ages provided the reference material. The infrared vibrations detected in infrared transmission spectra depended on the chemical structure of examined compound. Comparable distinctive peaks in infrared spectra of natural teeth and inorganic dental materials (porcelain) were exhibited. Analogous infrared spectra of dental materials consisting of organic matrix with inorganic fillers were found. In the case of acrylic materials specific organic groups were enhanced. The prepared database of infrared transmission spectra included 23 dental materials, facilitating their appropriate identification. Application of infrared spectroscopy allowed for a quick differential identification of typical dental materials produced from organic compounds for inorganic restorations (porcelain) and of tooth structure-resembling hydroxyapatite and its contaminate forms with fluoride and carbonate ions.

H?dzelek, W.; Marcinkowska, A.; Domka, L.; Wachowiak, R.

2008-08-01

125

Rugometric and microtopographic inspection of teeth enamel  

NASA Astrophysics Data System (ADS)

The roughness of teeth' enamel is an important parameter in orthodontics. One example is the application in the process of decreasing tooth-size by reducing the interproximal enamel surfaces (stripping) of teeth. In order to achieve smooth surfaces clinicians have been testing various methods and progressively improved this therapeutic technique. The evaluation the surface roughness following teeth interproximal reduction is fundamental in the process. In general tooth' surface is not flat presenting a variety of complex geometries. In this communication we will report on the metrological procedure employed on the rugometric and microtopographic inspection by optical active triangulation of raw and processed (interproximal stripping) tooth surfaces.

Costa, Manuel F.; Pereira, Pedro B.

2013-06-01

126

Bovine colostrum immunoglobulin concentrate for cryptosporidiosis in AIDS  

Microsoft Academic Search

Lactobin-R is a commercial hyperimmune bovine colostrum with potent anticryptosporidial activity. It was administered to a 4 year old child with AIDS and severe diarrhoea associated with cryptosporidiosis. There was significant clinical improvement in the diarrhoea and permanent elimination of the parasite from the gut as assessed through serial jejunal biopsy and stool specimens.

J Shield; C Melville; V Novelli; G Anderson; I Scheimberg; D Gibb; P Milla

1993-01-01

127

Cleaning Your Child's Mouth and Teeth  

MedlinePLUS

... and Flossing Who Does the Brushing? Brushing Flossing Toothpaste From Mouth Wipes to Brushing and Flossing As ... sized toothbrush. Use a very small smear of toothpaste. Your child's teeth don't touch each other ...

128

Taking Care of Your Teeth and Mouth  

MedlinePLUS

... can protect your teeth from decay by using fluoride toothpaste. If you are at a higher risk ... of medicines you take), you might need more fluoride. Your dentist or dental hygienist may give you ...

129

Flouride. Ten-year prospective study of deciduous and permanent dentition.  

PubMed

A ten-year longitudinal prospective study compared the effect of fluoride on dentition of 1,500 children from infancy through age 10 years. In Kalamazoo, Mich, and Oneida, NY, parallel groups were given a fluoride-vitamin supplement from infancy and from age 4 and compared with fluoridated water and control groups. Incidence of new caries activity in both deciduous and permanent teeth was measured by mean number of new decayed and filled teeth, as well as percentage of children with no caries throughout the periods studied. Prevalence of caries was also studied in six-year molars. The results indicate a consistent (and, for selected groups, a statistically significant) diminution in caries activity for both deciduous and permanent teeth for groups ranked from greatest retardation of caries to least: infant fluoride group, water fluoride group, age 4 fluoride group, and controls. PMID:1096595

Margolis, F J; Reames, H R; Freshman, E; MaCauley, C D; Mehaffey, H

1975-07-01

130

First permanent molar root development arrest associated with compound odontoma.  

PubMed

Trauma or infection to the primary tooth may have deleterious effects on the underlying developing tooth buds. Anatomically the root apices of primary teeth are in close proximity to the developing permanent tooth buds; hence spread of infection originating from pulp necrosis of primary tooth may not only affect the underlying tooth bud but may also affect the adjacent tooth buds. The extent of malformation depends on the developmental stage of tooth or the age of patient. Presented here is a rare case of complete arrest of maxillary first permanent molar root growth due to spread of periapical infection originating from second primary molar leading to failure of its eruption and finally extraction. Histopathlogical analysis revealed compound odontoma associated with maxillary first permanent molar. PMID:23832997

Gunda, Sachin A; Patil, Anil; Varekar, Aniruddha

2013-01-01

131

Drug-induced disorders of teeth.  

PubMed

It is essential that every health care professional who is involved with the prescription or recommendation of drugs be fully aware of any resultant disorders that may arise as a side-effect. A range of drugs can affect the teeth. In this review article, drugs that have the potential to induce changes in teeth have been classified as those leading to tooth discoloration (intrinsic and extrinsic), physical damage to tooth structure (enamel, dentin, and cementum), and alteration in tooth sensitivity. PMID:15972585

Tredwin, C J; Scully, C; Bagan-Sebastian, J-V

2005-07-01

132

Dissolution of Human Teeth-Derived Hydroxyapatite  

Microsoft Academic Search

We have been interested in human teeth which consist of hydroxyapatite (HA), but do not degrade for a long time. In order\\u000a to overcome dissolution and mechanical degradation of man-made HA, biologically derived hydroxyapatite (BHA) ceramics were\\u000a prepared from human teeth and their dissolving behavior was investigated in distilled water for 3–14 days and compared with\\u000a an artificial HA made of

Dong Seok Seo; Jong Kook Lee

2008-01-01

133

Nova Scotia Dental Association: Healthy Teeth  

NSDL National Science Digital Library

What exact role does sugar play in the formation of cavities? Find the answer to this question and many more at Healthy Teeth, a comprehensive and lively oral health education website for 3rd-6th graders and created by the Nova Scotia Dental Association. The site contains sections on Cavities, Teeth and Gums, Prevention, and more. The sections are student-friendly with straightforward text and fun animated images. Additionally, the site offers hands-on classroom activities and experiments.

134

Evaluation and Comparison of Changes in Microhardness of Primary and Permanent Enamel on Exposure to Acidic Center-filled Chewing Gum: An in vitro Study  

PubMed Central

ABSTRACT Objectives: The study is to evaluate changes in microhardness of enamel after exposure to acidic center filled chewing gum on primary and permanent teeth. Methods: Thirty primary and 30 permanent molar extracted teeth were painted with acid resistant varnish except a small window over buccal surface. Teeth were divided into four groups according to type of teeth and type of chewing gum (Center fresh and Bubbaloo) (D1, P1, D2 and P2); each tooth was exposed to whole chewing gum mashed with 5 ml of artificial saliva for five minutes at room temperature twice a day for 5 days. After the exposure, teeth were stored in deionized water and submitted for microhardness tests. Results: Paired t-test and independent sample t-test were used for statistical analysis. A significant reduction in microhardness was found between exposed and unexposed areas in all groups. There was no statistically significant difference in reduction of microhardness to chewing gums, and between primary and permanent enamel. Conclusion: There is a definite reduction in microhardness in all groups exposed to chewing gums. Both the chewing gums are equally erosive; both permanent and primary teeth were affected. How to cite this article: Mudumba VL, Muppa R, Srinivas NCH, Kumar DM. Evaluation and Comparison of Changes in Microhardness of Primary and Permanent Enamel on Exposure to Acidic Center-filled Chewing Gum: An in vitro Study. Int J Clin Pediatr Dent 2014;7(1):24-29. PMID:25206233

Muppa, Radhika; Srinivas, NCH; Kumar, Duddu Mahesh

2014-01-01

135

Management of complications after traumatic injuries to immature permanent maxillary incisors: a five years follow up case report.  

PubMed

The management of traumatic injuries to the teeth and soft tissues represent a challenge for the dental practitioner requiring knowledge and expertise necessary for adequate diagnosis and treatment. The purpose of this case report is to illustrate the emergency, short and long-term management of young permanent teeth involved with complex luxation injuries. Emergency management, orthodontic forced eruption and pulp therapy approaches used are described in details. The case was followed-up clinically and radiographically for 5 years. PMID:24984660

Halima, Abukabbos; Faisal, Alsineedi; Marcio, Guelmann

2014-06-01

136

Medico-legal aspects of postmortem pink teeth  

Microsoft Academic Search

Summary While the phenomenon of pink teeth has been known since 1829, when it was first described by Bell, its application in forensic medicine has been limited. Recently, however, attention was again focused on pink teeth in legal cases. The medico-legal implication was the use of pink teeth as a possible means of evaluating the cause of death. Pink teeth

H. Borrman; A. Du Chesne; B. Brinkmann

1994-01-01

137

Bilateral supplemental permanent maxillary lateral incisors in a non-syndromic patient.  

PubMed

A supernumerary tooth is an additional entity to the normal series and can be seen in all quadrants of the jaw. Occurrence may be single or multiple, unilateral or bilateral, erupted or impacted in one or in both jaws. Multiple supernumeraries are rare in individuals with no other associated disease or syndromes. The conditions commonly associated with an increased prevalence of supernumerary teeth include cleft lip and palate, cleidocranial dysplasia and Gardner syndrome. The supplemental supernumerary refers to a duplication of teeth in normal series and is found at the end of a tooth series. A supplemental tooth may closely resemble the teeth of the group to which it belongs or it may bear little resemblance in size or shape to the teeth with which it is associated. This report presents a case with bilateral supplemental upper permanent lateral incisors without any symptoms of associated disorders. PMID:25168674

Bhullar, Mandeep Kaur; Uppal, Amandeep Singh; Kochhar, Gulsheen Kaur; Singh, Ranjit

2014-01-01

138

A case report of a rare finding of supernumerary primary and permanent canines  

PubMed Central

A supernumerary tooth is a tooth that is additional to the normal series of teeth. These can occur anywhere in the primary or permanent dentition and are most commonly found in the anterior maxilla. Supernumerary canines are rare with little available literature and case reports in this area. This case presents a patient with a unilateral maxillary supernumerary deciduous and permanent canine associated with an unusual cleft of the alveolus. How to cite the article: Parker K, Hay N. A case report of a rare finding of supernumerary primary and permanent canines. J Int Oral Health 2014;6(2):129-131. PMID:24876714

Parker, Kate; Hay, Norman

2014-01-01

139

Solid modeling of fossil small mammal teeth  

NASA Astrophysics Data System (ADS)

This paper presents an approach to create solid models of fossil small mammal teeth using a combination of microcomputed tomography, object based image analysis and voxel modeling. Small mammal teeth, because of their durability, are widely found in Cenozioc sediments the world over and play a key role in stratigraphy as well as in researching the rapid evolution and the paleogeographic spreading of small mammals. Recent advances in microcomputed tomography make this non-destructive analysis method an ideal data source for high-resolution 3D models of fossil small animal teeth. To derive internally consistent solid models of such fossils from micro-CT imagery, we propose a combination of 3D object based image analysis and solid modeling. Incorporating paleontological expert knowledge in the image processing cycle, object based image analysis yields topologically consistent image stacks classified by the main tooth components—enamel, dentine and pulp. Forwarding these data to a voxel modeling system, they can be quantitatively analyzed in an unprecedented manner: going beyond the possibilities of the state-of-art surface models, solid models are capable of unambiguously portraying the entire object volume—teeth can be peeled by material properties, subvolumes can be extracted and automatically analyzed by Boolean operations. The proposed method, which can be flexibly extended to handle a range of paleontological and geological micro-objects, is demonstrated with two typical fossil small mammal teeth.

Marschallinger, Robert; Hofmann, Peter; Daxner-Höck, Gudrun; Ketcham, Richard A.

2011-09-01

140

Human teeth model using photoacoustic frequency response  

NASA Astrophysics Data System (ADS)

In this paper, a novel photo-acoustic technique modality utilizing a frequency- modulated Q-switch Nd:YAG laser at 1064 nm and coherent frequency domain signal processing is introduced for impulse and frequency responses of biological tissues. We present a photoacoustic technique to monitor the temporal behavior of temperature and pressure in an excised sample of human teeth after either a single laser pulse or during multiple laser pulses at pulse repetition frequencies (PRF) from 5 Hz to 100 Hz. Knowledge of the dynamic characteristics of structural elements often means the difference between normal and abnormal tissue. The determination of the resonance characteristics of structures is termed "modal analysis." The results of our study suggest that it is possible to identify the impulse, frequency response and resonance modes of simplified human teeth. This data provided a powerful tool to differentiate between normal and decay teeth.

El-Sharkawy, Yasser H.; El-Sherif, Ashraf F.

2012-03-01

141

A Key to the Common Genera of Neogene Shark Teeth Robert W. Purdy  

E-print Network

A Key to the Common Genera of Neogene Shark Teeth by Robert W. Purdy Revised March 2006 #12 Variation 5 Basic Tooth Types 5 Lowers and uppers 5 Parasymphyseal teeth 5 Anterior teeth 6 Intermediate teeth 7 Lateral teeth 7 Posterior teeth 8 Teeth of no distinction 8 Tooth Variation Due to Ontogeny 9

Mathis, Wayne N.

142

BRUCELLOSE BOVINE EXPRIMENTALE VII. —  

E-print Network

BRUCELLOSE BOVINE EXPÃ?RIMENTALE VII. — INFLUENCE SUR L'Ã?VOLUTION DE L'INFECTION D'UNE FAIBLE à partir du mucus vaginal (avant et après mise bas), du colostrum, du lait, des organes et ganglions'Homme, enparticulier par les tétracyclines, l'usage de ces antibiotiques dans le traitement de la Brucellose bovine s

Paris-Sud XI, Université de

143

A KEY TO THE COMMON GENERA OF NEOGENE SHARK TEETH ROBERT W. PURDY  

E-print Network

A KEY TO THE COMMON GENERA OF NEOGENE SHARK TEETH BY ROBERT W. PURDY Revised April 2003 #12;2 Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Parasymphyseal teeth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Anterior teeth

Mathis, Wayne N.

144

Treatment of Ectopic Mandibular Second Permanent Molar with Elastic Separators  

PubMed Central

Ectopic eruption is a developmental disturbance in which the tooth fails to follow its normal eruption pathway. Ectopic eruption of the second molar is relatively rare. This paper presents the case of thirteen-year-old male with an ectopic mandibular second permanent molar. The condition was corrected with surgical exposure and placement of elastic separators. This case report lays emphasis on the practice of basic methods to obtain acceptable results rather than extensive surgical or orthodontic corrections. It is advised that ectopic teeth should not be neglected especially when it concerns developing caries and malocclusion. PMID:25050182

Rajesh, R.; Naveen, V.; Amit, S.; Baroudi, Kusai; Sampath Reddy, C.; Namineni, Srinivas

2014-01-01

145

Sterilisation of extracted human teeth for educational use.  

PubMed

Sixty intact, non-carious and unrestored teeth extracted due to periodontal disease were used to determine the most effective method of sterilisation. The teeth were divided into six groups, each containing 10 teeth. Group 1 teeth were immersed in 10% formalin for seven days, group 2 teeth were immersed in 3% hydrogen peroxide for seven days, group 3 teeth were immersed in 2.6% sodium hypochlorite for seven days, group 4 teeth were boiled in water at 100 degrees C for 20 minutes, group 5 teeth were autoclaved at 121 degrees C at 15 lbs psi for 30 minutes, and group 6 teeth were immersed in normal saline for seven days. After the treatment, the teeth were individually inoculated into trypticase soy broth and incubated for 48 hours. A questionnaire survey was also conducted to determine the awareness of dental students regarding infection due to extracted human teeth and the common disinfection/sterilisation methods used. Autoclaving at 121 degrees C, 15 lbs psi for 30 minutes and immersion in 10% formalin for seven days were effective in disinfecting/sterilising extracted human teeth. Chemicals such as 2.6% sodium hypochlorite, 3% hydrogen peroxide and boiling in water were not effective. The results indicate that autoclaving for 30 minutes or immersion in 10% formalin for seven days could be effectively used for disinfection/sterilisation of extracted human teeth. PMID:16327123

Kumar, M; Sequeira, P S; Peter, S; Bhat, G K

2005-10-01

146

Simulating Clinical Carious Lesions in Composition Teeth.  

ERIC Educational Resources Information Center

A step-by-step technique to alter stock composition teeth and create simulated carious conditions that are ideal or otherwise is presented. The procedures provide the student with life-like lesions, suitable in texture and location and similar to conditions found in the oral cavity. (MLW)

Ambrose, E. R.; And Others

1981-01-01

147

Healthy teeth can last a lifetime! Tooth  

Microsoft Academic Search

decay and loss from oral diseases lead to costly dental work and dentures, was once accepted as a natural part of aging. Today more adults than ever are keeping their teeth well into their advanced years, presenting challenges for long-term and community caregivers. In spite of improvements in oral health, the elderly who are disadvantaged suffer severe tooth destruction and

Mary Kaplan; Donna Jacobi; Terry Dolan

148

Effects of bleaching on teeth and restorations.  

PubMed

This article describes how at-home bleaching procedures affect teeth and restorative materials. Specifically, it discusses the effects of tooth-whitening systems on enamel surfaces, enamel and dentin bond strengths, marginal integrity, color, and other properties of restorative materials. PMID:9918105

Swift, E J; Perdigão, J

1998-08-01

149

Hierarchical structure and biomineralization in cricket teeth  

NASA Astrophysics Data System (ADS)

The cricket is a truculent insect with stiff and sharp teeth as a fighting weapon. The structure and possible biomineralization of cricket teeth are always interesting. Synchrotron radiation X-ray fluorescence, X-ray diffraction, and small angle X-ray scattering techniques were used to probe the element distribution, possible crystalline structures and size distribution of scatterers in cricket teeth. A scanning electron microscope was used to observe the nanoscaled structure. The results demonstrate that Zn is the main heavy element in cricket teeth. The surface of a cricket tooth has a crystalline compound like ZnFe2(AsO4)2(OH)2(H2O)4. The interior of the tooth has a crystalline compound like ZnCl2, which is from the biomineralization. The ZnCl2-like biomineral forms nanoscaled microfibrils and their axial direction points towards the top of the tooth cusp. The microfibrils aggregate randomly into intermediate filaments, forming a hierarchical structure. A sketch map of the cricket tooth cusp is proposed and a detailed discussion is given in this paper.

Xing, Xue-Qing; Gong, Yu; Cai, Quan; Mo, Guang; Du, Rong; Chen, Zhong-Jun; Wu, Zhong-Hua

2013-02-01

150

Gold-coloured Teeth of Sheep  

Microsoft Academic Search

DURING the early part of the war the transport of sheep about the country districts was strictly regulated so that a local butcher could state definitely in which locality his meat had been fed. I noticed a large number of sheep's teeth encrusted with bright yellow tartar, identical in appearance with good average bright non-arsenical iron pyrites. I was assured

W. J. Lewis Abbott

1921-01-01

151

Simulation of a flow around biting teeth  

NASA Astrophysics Data System (ADS)

We simulated a flow around biting teeth. The decayed tooth is a disease that a majority of people are annoyed. These are often generated from a deep groove at occlusal surface. It is known that a person who bites well doesn't suffer from a decayed tooth easily. Biting forces reach as much as 60 kg/cm^2 by an adult male, and when chewing, upper and lower teeth approach to bite by those forces. The crushed food mixed with saliva becomes high viscosity fluid, and is pushed out of ditches of teeth in the direction of the cheek or the tongue. Teeth with complex three dimension curved surface are thought to form venturi at this time, and to generate big pressure partially. An excellent dental articulation will possibly help a natural generation of a flow to remove dental plaque, i.e. the cause of the decayed tooth. Moreover, the relation of this flow with the destruction of the filled metal or the polymer is doubted. In this research, we try to clarify the pressure distributions by this flow generation as well as its dynamics when chewing. One of our goals is to enable an objective design of the shape of the dental fillings and the artificial tooth. Tooth has a very small uneven ground and a bluff body. In this case, to calculate a computational numerical simulation to solve the Navier-Stokes equations three dimension Cartesian coordinate system is employed.

Narusawa, Hideaki; Yamamoto, Eriko; Kuwahara, Kunio

2008-11-01

152

The large superpredators' teeth from Middle Triassic of Poland  

NASA Astrophysics Data System (ADS)

An unusual large teeth, finding from time to time in marine sediments of Muschelkalk, Silesia, Poland indicate the superpredators occurrence. According to size and morphological features the teeth are similar to archosaurs or giant marine reptiles.

Surmik, Dawid; Brachaniec, Tomasz

2013-09-01

153

Variable Permanent Magnet Quadrupole  

SciTech Connect

A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments.

Mihara, T.; Iwashita, Y.; /Kyoto U.; Kumada, M.; /NIRS, Chiba; Spencer, C.M.; /SLAC

2007-05-23

154

Morphometric, densitometric and mechanical properties of mandibular deciduous teeth in 5-month-old Polish Merino sheep  

PubMed Central

Background Caries, enamel hypoplasia, molar incisor hipomineralization, amylogenesis imperfecta, dentine dysplasia, hypophosphatasia and other dental disorders lead to tooth mineralization disturbances and structural abnormalities, decreasing masticatory organ functions. Dental disorders in sheep can lead to premature slaughter before they have attained final stage of their reproductive life and induce economic loss due to high flock replacement costs. Growth rate, health status and meat quality of sheep depends on tooth properties and quality determining in large extent efficiency of the masticatory apparatus and initial food break up. Considering lack of basic anatomical and physiological data on teeth properties in sheep, the aim of the study was to evaluate morphometric, densitometric and mechanical traits of deciduous mandibular incisor, canine and the second premolar obtained at the slaughter age of 5 months of life. Results The obtained results have shown the highest values of weight, total tooth volume, enamel volume and dentine volume in second premolar. Morphometric and mechanical parameters of incisors reached the highest values in first incisor and decreased gradually in second and third incisor, and in canine. Densitometric measurements have not revealed significant differences of the volumetric tooth mineral density in hard dental tissues between the investigated teeth. Conclusions In conclusion, proposed methodological approach is noninvasive since the deciduous teeth undergo physiological replacement with permanent teeth. Deciduous teeth can be easy collected for analyses from large animal population and may reflect mineral status and metabolism resulting from postnatal growth and development of the whole flock. In individual cases, evaluation of properties of deciduous teeth may serve for breeding selection and further reproduction of sheep possessing favorable traits of teeth and better masticatory system functions. PMID:24548814

2014-01-01

155

A Curriculum Vitae of Teeth: Evolution, Generation, Regeneration  

Microsoft Academic Search

The ancestor of recent vertebrate teeth was a tooth-like structure on the outer body sur- face of jawless fishes. Over the course of 500,000,000 years of evolution, many of those structures migrated into the mouth cavity. In addition, the total number of teeth per denti- tion generally decreased and teeth morphological complexity increased. Teeth form mainly on the jaws within

Despina S. Koussoulakou; Lukas H. Margaritis; Stauros L. Koussoulakos

2009-01-01

156

Form factors for generated unequal addendum and dedendum gear teeth  

E-print Network

PORN FACTORS FOR GEHERLTED DREQUkL LDDERDDH /AID DEDEHDDH GEAR TEETH GEORGE FREDERICK SHEETS, JH. approved as to style and oontent by: z Head of Departnent Hayi 1952 FORM FACTORS FOR GEEERATED UEEQUAL ADDEEDUM AED DEDEEDUM GEAR TEETH... PORN FACTORS FOR GEHERLTED DREQUkL LDDERDDH /AID DEDEHDDH GEAR TEETH GEORGE FREDERICK SHEETS, JH. approved as to style and oontent by: z Head of Departnent Hayi 1952 FORM FACTORS FOR GEEERATED UEEQUAL ADDEEDUM AED DEDEEDUM GEAR TEETH...

Sheets, George Frederick

2012-06-07

157

Appearance of the first cemental annulation of permanent incisor teeth of the domestic cat (Felis catus)  

E-print Network

Common Marmoset 5 ecies Alces alces Odocoileus hemiomus dd t liens ~i Curvus ~e1a hus Ursus americanus ~se hales h h f Canis latrans Ovis aries ~nti le Odocoileus hemionus Ovis dalli Lynx rufus ~Vul es fulva ~nil t d e lands Ovss... 36 ( 1): 46-55, 197Z . 17. Crowe 0 M: The pr esence of annuli in bobcat tooth cementum layers. J Wildl ~M mt 36(4):1330-1332, 1972. 18. Monson R A, Stone W 8, Parks E: Aging red foxes (~Yui es fulva) by counting the annular cementum rings...

Choi, In-Back

2012-06-07

158

Natural Teeth Replacing Artificial Teeth in a Partial Denture: A Case Report  

PubMed Central

The aesthetic replacement of anterior teeth in cases of immediate partial denture is always a challenging work for prosthodontists. There is always problem of matching size, colour, shade and shape of the replaced tooth with those of the natural teeth. It was most difficult to satisfy the patients who have high aesthetic demands. Here is a report of a case where patient’s own natural tooth was used for replacement in an immediate partial denture. An immediate denture is defined as “any removable dental prosthesis which is fabricated for placement immediately, following the removal of a natural tooth/teeth” . Patients with missing anterior teeth lack an impressive appearance aesthetically and as well as psychologically. Tooth loss leads to a certain degree of loss of function. This loss of function might lead to an impairment of oral health which is related to quality of life. An immediate denture can replace 1-16 teeth in either the maxillary or the mandibular arch, or in both arches. The need for the immediate replacement of a missing tooth is more in case of an anterior tooth, where aesthetics is of prime concern. The replacement of an anterior tooth is most technique sensitive, as it includes the patient’s expectations, which include, matching with proper shade, shape and size as those of his/her natural teeth. So, here is a case presentation where modern day patient expectations were taken into consideration. PMID:24086926

Satapathy, Sukanta Kumar; Pillai, Ajay; Jyothi, Ramya; Annapurna, P. Durga

2013-01-01

159

An Interactive Geometric Technique for Upper and Lower Teeth Segmentation  

E-print Network

An Interactive Geometric Technique for Upper and Lower Teeth Segmentation Binh Huy Le1 , Zhigang in semantics of both shape and form, a fully automated method for the separation of the lower and upper teeth a novel interactive method to segment the upper and lower teeth. The process is performed on 3D triangular

Azevedo, Ricardo

160

Spatial and Functional Modeling of Carnivore and Insectivore Molariform Teeth  

E-print Network

Spatial and Functional Modeling of Carnivore and Insectivore Molariform Teeth Alistair R. Evans, Australia ABSTRACT The interaction between the two main com- peting geometric determinants of teeth (the, dilambdodont, and tribosphenic). These models aim to emulate the shape and function of mammalian teeth

Evans, Alistair

161

Predicting evolutionary patterns of mammalian teeth from development  

E-print Network

ARTICLES Predicting evolutionary patterns of mammalian teeth from development Kathryn D. Kavanagh1 and number of cheek teeth, or molars, in the mouse. We constructed an inhibitory cascade model with human third molars, or wisdom teeth, which are frequently surgically removed with a risk

Evans, Alistair

162

Dual epithelial origin of vertebrate oral teeth Vladimir Soukup1  

E-print Network

LETTERS Dual epithelial origin of vertebrate oral teeth Vladimi´r Soukup1 , Hans-Henning Epperlein2 as an ectodermal invagination1,2 . Consistent with this, oral teeth are pro- posed to arise exclusively from to dentin and pulp3­5 . Yet in many vertebrate groups, teeth are not restricted only to the oral cavity6

Horacek, Ivan

163

Teeth Shape Modeling Pipeline for Oral Healthcare Appliances Development  

E-print Network

Teeth Shape Modeling Pipeline for Oral Healthcare Appliances Development (Invited Paper) Jacek teeth and gums geometries. The generated models may be used for various simulations with the end goal- and intra-subject variation of teeth geometry, developing devices that are as efficient as possible in all

Telea, Alexandru C.

164

Late Cretaceous Plesiosaur Teeth from Axel Heiberg Island, Nunavut, Canada  

Microsoft Academic Search

We report the discovery of Late Cretaceous plesiosaur teeth from non-marine strata on Axel Heiberg Island in the Canadian High Arctic. In comparison to other plesiosaur teeth, these specimens are most similar to the teeth of elasmosaurs: they have a smooth outer surface and crenulated inner surface, with crenulations that extend nearly to the tip of the tooth. Comparisons with

DEBORAH VANDERMARK; JOHN A. TARDUNO; DONALD B. BRINKMAN

2006-01-01

165

The evaluation of a novel method comparing quantitative light-induced fluorescence (QLF) with spectrophotometry to assess staining and bleaching of teeth  

Microsoft Academic Search

This study reports the development and evaluation of a novel method using quantitative light-induced fluorescence (QLF), which\\u000a enables its use for quantifying and assessing whole tooth surface staining and tooth whitening. The method was compared with\\u000a a spectrophotometer to assess reliability. Two experimental phases, intrinsic stain formation and tooth whitening, were conducted\\u000a in vitro on 16 extracted bovine teeth. Intrinsic

A. A. Adeyemi; F. D. Jarad; E. de Josselin de Jong; N. Pender; S. M. Higham

2010-01-01

166

Infectious Bovine Rhinotracheitis  

E-print Network

Infectious bovine rhinotracheitis (IBR) is a complex of disease syndromes occuring throughout the United States and the other major cattle-producing areas of the world. It affects cattle and some wild ruminants. This publication describes...

Sprott, L. R.

1998-11-30

167

Intraradicular reinforcement for traumatized immature teeth.  

PubMed

Immature necrotic teeth after trauma pose both endodontic and restorative challenges because of incomplete closure of the apex, and thin and weakened dentinal walls that make them prone to fracture. The use of light-transmitting plastic posts, in combination with adhesive materials, enable intraradicular reinforcement of flared canals, helping to rehabilitate fractured immature teeth and maintain a functional unit within the dental arch. The purpose of this paper is to present the case of a nine-year-old patient who had a complicated fracture of an immature anterior tooth, which was endodontically treated with mineral trioxide aggregate in the apical third. The dentinal root walls were successfully reinforced with composite resin and a light-transmitting glass fiber post, followed by the placement of a glass fiber composite post and a metal ceramic crown. PMID:24709431

Chhabra, Nidhi; Chhabra, Anuj

2014-01-01

168

Cleidocranial Dysplasia Case Report: Remodeling of Teeth as Aesthetic Restorative Treatment  

PubMed Central

Cleidocranial dysplasia (CCD), is an autosomal dominant disorder with a prevalence of 1 in 1,000,000 individuals. It is generally characterized by orofacial manifestations, including enamel hypoplasia, retained primary teeth, and impacted permanent and supernumerary teeth. The successful treatment involving a timing intervention (orthodontic-maxillofacial surgeons-restorative) is already described. However, the restorative treatment might improve the aesthetic final result in dentistry management for patients with cleidocranial dysplasia. Objective. Therefore, this clinical report presents a conservative restorative management (enamel microabrasion, dental bleaching, and direct composite resin) for aesthetic solution for a patient with CCD. Clinical Considerations. The cosmetic remodeling is a conservative, secure, and low cost therapy that can be associated with other procedures such as enamel microabrasion and dental bleaching to achieve optimal outcome. Additionally, the Golden Proportion can be used to guide dental remodeling to improve the harmony of the smile and the facial composition. Conclusions. Thus, dentists must know and be able to treat dental aesthetic problems in cleidocranial dysplasia patients. The intention of this paper is to describe a restorative approach with the cosmetic remodeling teeth (by grinding or addicting material) associated with enamel microabrasion and dental bleaching to reestablish the form, shape, and color of smile for patients with cleidocranial dysplasia. PMID:25045546

da Cunha, Leonardo Fernandes; Caetano, Isabela Maria; Dalitz, Fernando; Gonzaga, Carla Castiglia; Mondelli, Jose

2014-01-01

169

Cleidocranial dysplasia case report: remodeling of teeth as aesthetic restorative treatment.  

PubMed

Cleidocranial dysplasia (CCD), is an autosomal dominant disorder with a prevalence of 1 in 1,000,000 individuals. It is generally characterized by orofacial manifestations, including enamel hypoplasia, retained primary teeth, and impacted permanent and supernumerary teeth. The successful treatment involving a timing intervention (orthodontic-maxillofacial surgeons-restorative) is already described. However, the restorative treatment might improve the aesthetic final result in dentistry management for patients with cleidocranial dysplasia. Objective. Therefore, this clinical report presents a conservative restorative management (enamel microabrasion, dental bleaching, and direct composite resin) for aesthetic solution for a patient with CCD. Clinical Considerations. The cosmetic remodeling is a conservative, secure, and low cost therapy that can be associated with other procedures such as enamel microabrasion and dental bleaching to achieve optimal outcome. Additionally, the Golden Proportion can be used to guide dental remodeling to improve the harmony of the smile and the facial composition. Conclusions. Thus, dentists must know and be able to treat dental aesthetic problems in cleidocranial dysplasia patients. The intention of this paper is to describe a restorative approach with the cosmetic remodeling teeth (by grinding or addicting material) associated with enamel microabrasion and dental bleaching to reestablish the form, shape, and color of smile for patients with cleidocranial dysplasia. PMID:25045546

da Cunha, Leonardo Fernandes; Caetano, Isabela Maria; Dalitz, Fernando; Gonzaga, Carla Castiglia; Mondelli, José

2014-01-01

170

Optical characterization of one dental composite resin using bovine enamel as reinforcing filler  

NASA Astrophysics Data System (ADS)

The use of composite resins for restorative procedure in anterior and posterior cavities is highly common in Dentistry due to its mechanical and aesthetic properties that are compatible with the remaining dental structure. Thus, the aim of this study was to evaluate the optical characterization of one dental composite resin using bovine enamel as reinforcing filler. The same organic matrix of the commercially available resins was used for this experimental resin. The reinforcing filler was obtained after the gridding of bovine enamel fragments and a superficial treatment was performed to allow the adhesion of the filler particles with the organic matrix. Different optical images as fluorescence and reflectance were performed to compare the experimental composite with the human teeth. The present experimental resin shows similar optical properties compared with human teeth.

Tribioli, J. T.; Jacomassi, D.; Rastelli, A. N. S.; Pratavieira, S.; Bagnato, V. S.; Kurachi, C.

2012-01-01

171

Investigation on the utility of permanent maxillary molar cusp areas for sex estimation  

Microsoft Academic Search

Digital photogrammetric methods were employed to assess the level of sexual dimorphism present in permanent maxillary molar\\u000a cusp areas of black South Africans (130 males, 105 females). Odontometric standards were then developed for diagnosing sex,\\u000a based on the cusp area data derived for these teeth. Results demonstrated that all cusp area measurements of both the first\\u000a and second maxillary molars

P. James Macaluso Jr

2011-01-01

172

The FiCTION dental trial protocol - filling children's teeth: indicated or not?  

PubMed Central

Background There is a lack of evidence for effective management of dental caries (decay) in children’s primary (baby) teeth and an apparent failure of conventional dental restorations (fillings) to prevent dental pain and infection for UK children in Primary Care. UK dental schools’ teaching has been based on British Society of Paediatric Dentistry guidance which recommends that caries in primary teeth should be removed and a restoration placed. However, the evidence base for this is limited in volume and quality, and comes from studies conducted in either secondary care or specialist practices. Restorations provided in specialist environments can be effective but the generalisability of this evidence to Primary Care has been questioned. The FiCTION trial addresses the Health Technology Assessment (HTA) Programme’s commissioning brief and research question “What is the clinical and cost effectiveness of restoration caries in primary teeth, compared to no treatment?” It compares conventional restorations with an intermediate treatment strategy based on the biological (sealing-in) management of caries and with no restorations. Methods/Design This is a Primary Care-based multi-centre, three-arm, parallel group, patient-randomised controlled trial. Practitioners are recruiting 1461 children, (3–7 years) with at least one primary molar tooth where caries extends into dentine. Children are randomized and treated according to one of three treatment approaches; conventional caries management with best practice prevention, biological management of caries with best practice prevention or best practice prevention alone. Baseline measures and outcome data (at review/treatment during three year follow-up) are assessed through direct reporting, clinical examination including blinded radiograph assessment, and child/parent questionnaires. The primary outcome measure is the incidence of either pain or infection related to dental caries. Secondary outcomes are; incidence of caries in primary and permanent teeth, patient quality of life, cost-effectiveness, acceptability of treatment strategies to patients and parents and their experiences, and dentists’ preferences. Discussion FiCTION will provide evidence for the most clinically-effective and cost-effective approach to managing caries in children’s primary teeth in Primary Care. This will support general dental practitioners in treatment decision making for child patients to minimize pain and infection in primary teeth. The trial is currently recruiting patients. Trial registration Protocol ID: NCTU: ISRCTN77044005 PMID:23725316

2013-01-01

173

The permanent catheter.  

PubMed

An elderly woman receiving hemodialysis via a right brachiocephalic arteriovenous fistula presented to the clinic for elective removal of a tunneled hemodialysis catheter inserted 5 years ago. The catheter had not been removed earlier at the patient's request. Removal was now unsuccessful in the clinic. Exploration in the operating room revealed the innominate vein had fibrosed around the length of the catheter. The procedure was abandoned, catheter cut short and the remnant left in situ. This case serves as a reminder to exercise caution if there is difficulty in removing the catheter even after the cuff is dissected free, and to remove them once a working fistula or graft is available. Failing which, the patient bears an unnecessary risk of line infection, or as in this case, the catheter may unintentionally end up what its common misnomer "perm-cath" alludes to--becoming truly "permanent." PMID:24164973

Tan, Ek Khoon; Tan, Seck Guan

2014-04-01

174

Achieving permanency for LGBTQ youth.  

PubMed

This article brings together two significant efforts in the child welfare field: achieving permanence for youth in out-of-home care and meeting the needs of lesbian, gay, bisexual, transgender and questioning (LGBTQ) youth. During the past several years, a national movement has taken place to assure all children and youth have a permanent family connection before leaving the child welfare system; however, LGBTQ youth are not routinely included in the permanency discussions. At the same time, efforts in addressing the needs of LGBTQ youth have increased, but permanency is rarely mentioned as a need. This article offers models of permanence and practices to facilitate permanence with LGBTQ youth and their families. It also offers a youth-driven, individualized process, using youth development principles to achieve relational, physical, and legal permanence. Reunification efforts are discussed, including services, supports, and education required for youth to return to their family of origin. For those who cannot return home, other family resources are explored. The article also discusses cultural issues as they affect permanence for LGBTQ youth, and, finally, addresses the need for ongoing support services to sustain and support permanency. PMID:16846117

Jacobs, Jill; Freundlich, Madelyn

2006-01-01

175

Enamel pretreatment with Er:YAG laser: effects on the microleakage of fissure sealant in fluorosed teeth  

PubMed Central

Objectives The purpose of this in vitro study was to evaluate the microleakage and penetration of fissure sealant in permanent molar teeth with fluorosis after pretreatment of the occlusal surface. Materials and Methods A total of 120 third molars with mild dental fluorosis were randomly divided into 6 groups (n = 20). The tooth surfaces were sealed with an unfilled resin fissure sealant (FS) material. The experimental groups included: 1) phosphoric acid etching (AE) + FS (control); 2) AE + One-Step Plus (OS, Bisco) + FS; 3) bur + AE + FS; 4) bur + AE + OS + FS; 5) Er:YAG laser + AE + FS; and 6) Er:YAG laser + AE + OS + FS. After thermocycling, the teeth were immersed in 0.5% fuchsin and sectioned. Proportions of mircoleakage (PM) and unfilled area (PUA) were measured by digital microscope. Results Overall, there were significant differences among all groups in the PM (p = 0.00). Group 3 showed the greatest PM, and was significantly different from groups 2 to 6 (p < 0.05). Group 6 showed the lowest PM. Pretreatment with Er:YAG with or without adhesive led to less PM than bur pretreatment. There were no significant differences among groups in PUA. Conclusions Conventional acid etching provided a similar degree of occlusal seal in teeth with fluorosis compared to those pretreated with a bur or Er:YAG laser. Pretreatment of pits and fissures with Er:YAG in teeth with fluorosis may be an alternative method before fissure sealant application. PMID:25110641

Kianimanesh, Nasrin; Shayeghi, Bahareh

2014-01-01

176

Cytokine Levels in Gingival Crevicular Fluid of Erupting Primary Teeth Correlated With Systemic Disturbances Accompanying Teething  

Microsoft Academic Search

Purpose: The aim of this study was to investigate whether there are increased levels of the inflammatory cytokines IL-1ß, IL-8, and TNF? in the gingival crevicular fluid (GCF) of erupting primary teeth. This increase could explain such clinical manifesta- tions as fever, diarrhea, increased crying, and sleeping and eating disturbances that occur at this time. Methods: Sixteen healthy children aged

Joseph Shapira; Gisela Berenstein-Ajzman; DC Dan Engelhard; Sorel Cahan; Ina Kalickman; Vivian Barak

2003-01-01

177

Persistently infected cattle stabilise bovine viral diarrhea virus leading to herd specific strains  

Microsoft Academic Search

Animals persistently infected with BVDV are important in the epizootiology of the Bovine Viral Diarrhea (BVD) because they are a permanent source of contamination within a herd. These animals produce large quantities of virus and have, therefore, been proposed as responsible for generating antigenic variability. However, limited studies have failed to detect antigenic or genetic changes in viruses isolated at

C Hamers; C Lecomte; G Kulcsar; M Lambot; P.-P Pastoret

1998-01-01

178

Are teeth useful in estimating stature?  

PubMed

Estimating stature is an important step in reconstructive identification of skeletonized and dismembered human remains. While numerous body parts such as the skull and long bones have been used for the purpose, the dentition has seldom been applied. The present study has ventured to ascertain the usefulness of tooth crown measurements in stature prediction. Buccolingual and mesiodistal dimensions of all teeth (except third molars) and stature measurements were obtained from 95 living adults (47 females, 48 males). Correlation analysis revealed that 21 of the 56 tooth crown variables had a low albeit statistically significant correlation to stature (p < 0.05); correlation matrix computed for the crown variables showed significant inter-correlations between most teeth (problem of multi-collinearity). Therefore, instead of regular least square regression analysis, ridge regression was performed for the dentition, which revealed a moderate but statistically significant correlation to stature (R = 0.68; p < 0.0001). The ridge regression equation derived had a standard error of estimate (SEE) of 8.09 cm. The multiple correlation for tooth dimensions is lower to, and the SEE larger than, most other body parts. The moderate correlation is probably due to early completion of growth of tooth crowns vis-à-vis other parameters such as long bones that mature later and have a higher stature-correlation. This indicates that the dentition may be used only as a supplement to more robust indicators of stature. PMID:23756515

Prabhu, Sudeendra; Acharya, Ashith B; Muddapur, Mahadevayya V

2013-07-01

179

Cleidocranial dysplasia presenting with retained deciduous teeth in a 15-year-old girl: a case report  

PubMed Central

Introduction Cleidocranial dysplasia is a rare congenital defect of autosomal dominant inheritance caused by mutations in the Cbfa1 gene, also called Runx2, located on the short arm of chromosome 6. It primarily affects bones which undergo intramembranous ossification. This condition is of clinical significance to dentistry due to the involvement of the facial bones, altered eruption patterns and multiple supernumerary teeth. Case presentation Our patient, a 15-year-old Indian girl, presented with the typical features of prolonged retention of deciduous dentition and delayed eruption of permanent teeth, that is, mandibular prognathism along with other skeletal abnormalities like shrugged shoulder and the absence of clavicles. A multidisciplinary approach was followed, comprising orthodontic, surgical and pedodontic teams for management. Conclusion Successful treatment of such a case lies in a holistic approach that takes care of all aspects, including the primary pathology, the deformity itself and even the psychological angle. PMID:22260259

2012-01-01

180

Infrared Absorption Bands of Enamel and Dentin Tissues from Human and Bovine Teeth  

Microsoft Academic Search

The chemical components present in the hard tissue such as water, phosphate, carbonate and organic material strongly absorb infrared radiation. The research in dentistry area has a fundamental interest in identifying the chemical origin of all the bands present in the infrared region to study the chemical and thermal action on the hard dental tissues. To improve this technique it

Luciano Bachmann; Rolf Diebolder; Raimund Hibst; Denise Maria Zezell

2003-01-01

181

The bleaching efficiency of KTP and diode 810 nm lasers on teeth stained with different substances: An in vitro study.  

PubMed Central

Background and aims: The purpose of this study was to evaluate the bleaching efficiency of two different lasers (KTP and diode 810 nm) on teeth, randomly divided by means an Excel function (Microsoft Excel 2010 “Fx causale”) and stored in physiological solution, that were previously stained with different substances commonly considered as a cause of tooth discoloration, such as coffee, tea and red fruits and to investigate the role of laser irradiation in an experimental model, during the dental bleaching process. Methods: Three groups of 45 bovine teeth were created and immersed for one week in a solution of tea, coffee or red fruits respectively. Each group was divided into three sub-groups of fifteen teeth. One was bleached with a 30% hydrogen peroxide gel for 30 min only as control, another 15 teeth group was bleached with the gel plus 810 nm diode laser irradiation and the last group was bleached with the gel plus KTP irradiation. The lasers were applied in three cycles of 30 sec each with a power of 1.5 W localized on a 10 mm spot on the teeth. The temperature of the gel was checked during the bleaching procedure using a thermometer and the colour of each tooth was measured by a spectrophotometer. Results: Statistical analysis of the collected data was performed using Graph Pad Prism, version 6.01 software, Kruskal-Wallis test and Dunn's multiple comparison test and Mann-Whitney test. P value <0.0001 was considered extremely significant (***), P value between 0.001 to 0.01 very significant (**), P value between 0.01 to 0.05 significant (*) and P value >0.05 not significant (ns). By these tests diode laser was effective only at bleaching teeth stained with coffee meanwhile the KTP laser was efficient at bleaching teeth with coffee, tea and red fruits stains. Conclusion: This study suggests that a relation between the laser wavelength and the type of staining on the dental enamel and the efficacy of the whitening treatment exists. PMID:24771968

Lagori, G; Vescovi, P; Merigo, E; Meleti, M.; Fornaini, C

2014-01-01

182

BRUCELLOSE BOVINE EXPRIMENTALE XII. —  

E-print Network

BRUCELLOSE BOVINE EXPÃ?RIMENTALE XII. — PERSISTANCE A L'Ã?GE ADULTE DE L'INFECTION CONGÃ?NITALE mammaire ante partum, le colostrum et le lait, dans les ganglions lymphatiques et organes des veaux ou in utero, ou celle du veau par ingestion de colostrum sont des faits bien établis, la transmission de la

Paris-Sud XI, Université de

183

Pharyngeal Teeth of the Freshwater Drum (Aplodinotus grunniens) a Predator of the Zebra Mussel (Dreissena polymorpha)  

Microsoft Academic Search

The morphology of pharyngeal teeth of freshwater drum (Aplodinotus grunniens) was studied to determine changes that occur during growth of drum that may relate to consumption of zebra mussel (Dreissena polymorpha) by larger fish. Pharyngeal teeth were of three types. Cardiform teeth were replaced by villiform teeth, which were replaced by molariform teeth as the size class of drum increased.

John R. P. French III

1997-01-01

184

Influence of antioxidants on stress of bonding agents in recently whitened teeth.  

PubMed

The aim of this study was to evaluate the influence of time of application of antioxidant agents on the bond strength to bovine enamel after bleaching by light emitting diode. Twenty two bovine incisors were used, on which the vestibular surfaces were flattened and divided into four experimental groups (n = 15) according to each antioxidant agent, with two groups each, varying the application time of 1 or 10 minutes, all submitted to the same whitening agent (Lase Peroxide) and the control group was only restored. The other groups were treated with antioxidant agents before the restorative procedure using the adhesive system All Bond 3 and resin Filtek Z-350. To obtain the dental fragments, teeth were placed in a precision cutter (Elquip), obtaining 0.8 mm 2 with sticks that were submitted to micro tensile testing at a test speed of 0.5 mm/min. The results, statistically analyzed by ANOVA and Tukey test (p < 0.05), indicated an increase in the value of bond strength of bleached groups treated with ascorbic acid, and a reduction when combined with sodium thiosulfate. No improvement in bond strength was found in the others. PMID:22550818

Braz, Rodivan; Patrício, Carlos E; Ribeiro, Ana I A M; Guênes, Gymenna M T; Dantas, Darlene C R E; Montes, Marcos A J R; Feitosa, Diala A S

2011-01-01

185

Linking development with generation of novelty in mammalian teeth  

E-print Network

are mammalian molar teeth, organs that have a good fossil record with high morphological diversity. Mammals have for review November 28, 1999) The evolution of mammalian teeth is characterized by the frequent and convergent evolution of new cusps. The evolution of new cusps can be linked to tooth development via

Jernvall, Jukka

186

Modified Anchor Shaped Post Core Design for Primary Anterior Teeth  

PubMed Central

Restoring severely damaged primary anterior teeth is challenging to pedodontist. Many materials are tried as a post core but each one of them has its own drawbacks. This a case report describing a technique to restore severely damaged primary anterior teeth with a modified anchor shaped post. This technique is not only simple and inexpensive but also produces better retention. PMID:25379294

Rajesh, R.; Baroudi, Kusai; Reddy, K. Bala Kasi; Praveen, B. H.; Kumar, V. Sumanth; Amit, S.

2014-01-01

187

Esthetic rehabilitation of discolored anterior teeth with porcelain veneers  

PubMed Central

The common man is bombarded by the media extolling the virtues of “the perfect smile.” In the 21st century of esthetic dentistry, fractured, malformed, malposed, and discolored teeth can be changed and restored to highly desirable form due to introduction of wide range of esthetic materials and techniques. Porcelain veneers is a conservative method of restoring the appearance of discolored, pitted teeth, and teeth with diastemas that provide extremely good esthetic results. A 21-year-old female patient with staining in anterior teeth had reported to the Department of Prosthodontics for esthetic rehabilitation. The patient was treated with porcelain veneers on maxillary anterior teeth. The patient was satisfied with the enhanced esthetic appearance. PMID:23853471

Kamble, Vaibhav D.; Parkhedkar, Rambhau D.

2013-01-01

188

Improvement in properties of plastic teeth by electron beam irradiation  

NASA Astrophysics Data System (ADS)

Improvement of the comfort and esthetics of artificial plastic teeth is desirable for the recently increasing numbers of elderly in society. Plastic teeth made of polycarbonate (PC) were modified by electron beam (EB) irradiation under specific conditions, and the change in the chemical properties of the PC was investigated. The water absorption, glucose attachment, level of bis-phenol-A (BPA) extraction, maltose adhesion, and mucin adhesion on the PC teeth were measured before and after EB irradiation. EB irradiation to a dose of 3.5 kGy at 150 °C in a nitrogen gas atmosphere reduced the water absorption by 20%, glucose absorption by 40%, maltose adhesion by 20%, and the amount of various amino acids, formed as the hydrolysis products of mucin, adhering on the PC teeth were reduced by 60-99%. The BPA content was lower than the detection limit for analysis of both the original and the EB irradiated PC teeth.

Sano, Yuko; Ishikawa, Shun-ichi; Seguchi, Tadao

2011-11-01

189

Non-syndromic multiple supernumerary teeth: a rare entity.  

PubMed

Hyperdontia or supernumerary teeth without associated syndromes is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardeners syndrome, cleidocranial dysplasia, trichorhinophalangic syndrome, etc. A 15-year-old girl reported for orthodontic treatment with a chief complaint of irregular teeth and unaesthetic smile. On examination class I malocclusion with severe crowding of upper anteriors, anterior open bite of 5 mm, cross bite with upper right posteriors, upper midline shift to right by 5 mm and two supernumerary teeth placed buccally in between 16 & 17 and 26 & 27, respectively, were found. On routine radiographical examination, two additional impacted supernumerary teeth were noticed distal to 18 and in mandibular arch in between roots of 35 and 36. A general physician was consulted who confirmed that there was no associated syndrome. Family history did not reveal any positive findings. PMID:23314450

Agrawal, Jiwanasha Manish; Agrawal, Manish Suresh; Nanjannawar, Lalita Girish; Adaki, Raghavendra Vithalappa

2013-01-01

190

Shape optimization of closed slot type permanent magnet motors for cogging torque reduction using evolution strategy  

SciTech Connect

Permanent magnet motors have been used in a wide variety of industrial applications. For the improvement of servo performances in the permanent magnet motors, a closed slot is adopted in the stator and a rare-earth magnet is used in the rotor. Here, the analysis of a permanent magnet type AC servo motor with both a closed slot and a ring shape magnet is performed by using the finite element method (FEM). The saturation of the bridge part connecting two slot teeth is considered for a nonlinear analysis. The optimal design of the stator is presented for minimizing cogging torque. The torques, i.e., cogging and rated torques are expressed in terms of vector potential computed by directly applying the Maxwell Stress Tensor formula. The minimization of cogging torque of sample model is achieved by using the (1+1) Evolution Strategy (ES) and the rated torque must be more than the specific value.

Chun, J.S.; Jung, H.K. [Seoul National Univ. (Korea, Republic of). School of Electrical Engineering; Yoon, J.S. [LG Industrial Systems Co., Ltd., Anyang, Kyongki (Korea, Republic of)

1997-03-01

191

Torque Characteristics of Saturated Permanent-Magnet Synchronous Motors  

NASA Astrophysics Data System (ADS)

The evaluation of torque characteristics in a saturated magnetic field for permanent-magnet (PM) synchronous motors is presented. The torque saturation characteristics of non-salient and salient pole machines are investigated by finite element analysis and measurement. Thus, it is found that the torque saturation originates in the magnetic saturation in both the stator teeth, which are located on the leading position toward the direct axis, and in the stator back yoke, which is located on the lagging position toward the direct axis. This mechanism can also explain the reason for the significant torque saturation in the salient-pole machine; the higher inductance of the quadrature axis of the salient-pole machine causes a significant magnetic saturation in the stator back yoke. Therefore, less saliency or a wider back yoke can improve the torque saturation.

Takahashi, Akeshi; Kikuchi, Satoshi; Wakui, Shinichi; Mikami, Hiroyuki; Ide, Kazumasa; Shima, Kazuo

192

ArteFill ® Permanent Injectable for Soft Tissue Augmentation: II. Indications and Applications  

Microsoft Academic Search

Patients ask for procedures with long-lasting effects. ArteFill is the first permanent injectable approved in 2006 by the\\u000a FDA for nasolabial folds. It consists of cleaned microspheres of polymethylmethacrylate (PMMA) suspended in bovine collagen.\\u000a Over the development period of 20 years most of its side effects have been eliminated to achieve the same safety standard\\u000a as today’s hyaluronic acid products. A

Gottfried Lemperle; Neil S. Sadick; Terry R. Knapp; Stefan M. Lemperle

2010-01-01

193

Bovine testicular heparin sulfamidase  

Microsoft Academic Search

Heparin sulfamidase was purified 2200-fold in 7% yield from bovine testis by a procedure which consisted of homogenization of the tissue in the presence of Triton X-100, ammonium sulfate fractionation, chromatography on concanavalin A-Sepharose, chromatography on heparin-Sepharose, and chromatofocusing. As shown by SDS-PAGE, the most highly purified preparation contained one major component, which had a mobility corresponding to a molecular

Jon T Conary; Lennart Rodén; Kenneth B Taylor; Jerry N Thompson

1987-01-01

194

Traumatic injuries of the permanent incisors in children in southern Turkey: a retrospective study.  

PubMed

The aim of this study is to investigate the incidence, etiologic factors and results of dental trauma and the effects of age and gender on the trauma in permanent incisors. Over a 3-year period, 514 permanent incisor teeth in 317 patients with trauma history, who applied to Suleyman Demirel University School of Dentistry, Department of Pedodontics from the southern cities of Turkey, were evaluated. Standardized trauma forms were filled for each patient. In all age groups, the most frequent cause of trauma was found to be unspecified falls (47.6%). Maxillary teeth (88.5%) and central incisors (87.5%) were the most affected teeth from dental trauma. Ellis class II crown fracture was the most frequently seen type of injury (43.8%). The percent of the patients who applied to a dental clinic in the first 3 days after the trauma occurred (22.8%) was less than the percent of the patients who applied after 3 months and more time period (45.1%). It reveals that it is important to inform the public about dental trauma and the importance of time in these cases. PMID:15660751

Zuhal, Kirzio?lu; Semra, Ozay Ertürk M; Hüseyin, Karayilmaz

2005-02-01

195

Indirect pulp therapy: an alternative to pulpotomy in primary teeth.  

PubMed

Preservation of the primary teeth until their normal exfoliation is essential for normal oral function and facial growth of the child. To that end, treatment of primary teeth with large carious lesions approximating the pulp should be aimed at preserving the tooth. Currently, the pulpotomy is the most frequently used pulp treatment for cariously involved primary teeth. The purpose of this manuscript is to describe the use of an alternative to the pulpotomy, indirect pulp therapy (IPT), for the treatment of vital, primary teeth with carious involvement approaching the pulp. Accurate diagnosis of the vitality status of the pulp is critical to the success of IPT and involves careful radiographic and clinical assessment of the teeth to be sure they are healthy or at worst, reversibly inflamed. The indications for IPT are the same as for pulpotomy. The technique involves one appointment, requires that some carious dentin be left to avoid pulp exposure and requires the placement of a biologically sealing base and sealing final restoration. Teeth treated with IPT have success rates at least as good as those treated with pulpotomies, and IPT offers an acceptable alternative to pulpotomy as a treatment for vital, asymptomatic, cariously involved primary teeth. PMID:21309277

Seale, N Sue

2010-11-01

196

Estimation of age from development and eruption of teeth  

PubMed Central

The developing dentition is used to assess maturity and estimate the age in many disciplines including anthropology, archeology, forensic science, pediatric dentistry and orthodontics. There is evidence that dental development is less effected than skeletal development by malnutrition and hormonal disorders. There are two methods of dental age assessment, radiographically and by clinically visualization of eruption of teeth. The clinical method to assess dental age is based on the emergence of teeth in the mouth. This method is more suitable since it does not require any special equipment, expertise and is more economical. Tooth formation is the best choice for estimating the age as variations are less as compared to other development factors. Eruption of teeth is one of the changes observed easily among the various dynamic changes that occur from the formation of teeth to the final shedding of teeth. The times of eruption of teeth are fairly constant and this can be made use of in ascertaining the average age of eruption of the tooth. Assessment of age of an individual by examination of teeth is one of the accepted methods of age determination. PMID:25125911

Manjunatha, B. S.; Soni, Nishit K.

2014-01-01

197

Multiple congenitally missing teeth treated with autotransplantation and orthodontics.  

PubMed

Treatment of children with several congenitally missing teeth is challenging, because growth and development of the oral structures must be considered. The treatment options include retaining the deciduous teeth and postponing treatment until later or extracting the deciduous teeth and doing one of the following: allowing the space to close spontaneously, closing the space orthodontically, or in patients whose growth is finished, using a prosthetic or implant replacement. One other viable option, if donor teeth are available, is autotransplantation. The treatment plan for patients with missing teeth should be based on a comprehensive evaluation of the patient's age, occlusion, and space requirements as well as on the size and shape of the adjacent teeth. This case report presents the management of a patient in the early mixed dentition with multiple missing teeth. The treatment consisted of a combination of autotransplantation of the maxillary right first premolar to the mandibular right first premolar region and orthodontic treatment with a 5-year follow-up after autotransplantation. PMID:22554758

Park, Jae Hyun; Tai, Kiyoshi; Yuasa, Kenji; Hayashi, Daisuke

2012-05-01

198

Endodontically treated teeth and periapical findings in the elderly.  

PubMed

The radiographic quality of root-canal fillings, the prevalence of periapical findings and their associations with gender and age were investigated in 133 dentate old people living at home (45 males and 88 females, aged 76, 81, and 86 years and who had endodontically treated teeth or periapical lesions. Sixteen per cent of the endodontically treated teeth (n=507) exhibited periapical lesions, compared with 4% for the teeth not endodontically treated (P<0.0001) (chi-square test). Lesions were least prevalent in association with radiographically adequate root canal fillings (10%), and most prevalent in teeth with root canal post perforation (100%). Overfilled root canals and multi-rooted teeth with one or more unfilled roots also showed a high percentage of lesions (19% and 22%, respectively). Men had more periapical lesions than women in endodontically treated teeth (P<0.001, Mann-Whitney U-test), a finding contrary to previous studies in younger subjects. There were no other statistically significant differences between the sexes or age groups, although the percentage of root-filled teeth increased with age. PMID:8595942

Soikkonen, K T

1995-07-01

199

A Curriculum Vitae of Teeth: Evolution, Generation, Regeneration  

PubMed Central

The ancestor of recent vertebrate teeth was a tooth-like structure on the outer body surface of jawless fishes. Over the course of 500,000,000 years of evolution, many of those structures migrated into the mouth cavity. In addition, the total number of teeth per dentition generally decreased and teeth morphological complexity increased. Teeth form mainly on the jaws within the mouth cavity through mutual, delicate interactions between dental epithelium and oral ectomesenchyme. These interactions involve spatially restricted expression of several, teeth-related genes and the secretion of various transcription and signaling factors. Congenital disturbances in tooth formation, acquired dental diseases and odontogenic tumors affect millions of people and rank human oral pathology as the second most frequent clinical problem. On the basis of substantial experimental evidence and advances in bioengineering, many scientists strongly believe that a deep knowledge of the evolutionary relationships and the cellular and molecular mechanisms regulating the morphogenesis of a given tooth in its natural position, in vivo, will be useful in the near future to prevent and treat teeth pathologies and malformations and for in vitro and in vivo teeth tissue regeneration. PMID:19266065

Koussoulakou, Despina S.; Margaritis, Lukas H.; Koussoulakos, Stauros L.

2009-01-01

200

Overeruption of teeth opposing removable partial dentures: a preliminary study.  

PubMed

One of the purposes of prosthodontic treatment is to prevent overeruption of opposing teeth, but there is currently minimal literature describing the efficacy of removable partial dentures (RPDs) in performing this function. This study investigated overeruption following RPD treatment. The study participants were 33 patients treated with RPDs, and overeruption was evaluated by comparing the surface computeraided design data of dental casts made at two different time points-before and after RPD treatment. Overeruption was observed in 38.1% of teeth opposed by the RPD, which was much less than the proportion of teeth that overerupted when not opposed by the RPD. PMID:25191893

Matsuda, Ken-Ichi; Miyashita, Yuji; Ikebe, Kazunori; Enoki, Kaori; Kurushima, Yuko; Mihara, Yusuke; Maeda, Yoshinobu

2014-01-01

201

Postpubertal nonfamilial cherubism and teeth transposition.  

PubMed

Cherubism is a rare, nonneoplastic, fibro-osseous disease. It is an autosomal-dominant disorder in which the normal bone is replaced by cellular fibrous tissue and immature bone. It is genetically inherited, although many nonfamilial cases have been reported. Cherubism is a bone disease clinically characterized by bilateral, painless enlargements of the jaws. The mandible is the most severely affected craniofacial component, in which uncontrolled growth of the malady deteriorates the aesthetic balance of the face. A malocclusive and abnormal dentition, worse in the mandible, can be seen. Histopathologically, numerous randomly distributed multinucleated giant cells and vascular spaces within a fibrous connective tissue stroma with or without eosinophilic collagen perivascular cuffing were apparent. The appearance of the affected children is normal at birth. Between the ages of 2 and 7 years, swellings within the mandibular body or tuberosities of maxilla appear. This article relates to a postpubertal nonfamilial cherubism case that was noticed with multiple radiolucencies in radiographic examination and its effects on teeth. PMID:20856051

Ozan, Bora; Mu?lali, Mehtap; Celenk, Peruze; Günhan, Omer

2010-09-01

202

Making Space for Permanent Molars in Growing Baboon (Papio anubis) and Great Ape (Pan paniscus and P. troglodytes) Mandibles: Possible Ontogenetic Strategies and Solutions  

PubMed Central

While mandible proportions do not appear to constrain permanent molar initiation times, how adequate space is created in the corpus for these teeth in a timely way is not well understood. This question is important for explaining how primate tooth and jaw development and evolution are coordinated. Landmark and linear measurement data were used to characterize mandible shape, growth trajectory, and growth rate between two genera, Papio and Pan, with contrasting permanent molar initiation schedules and mandible proportions. 3D geometric morphometric and 2D bivariate analyses showed genus-level differences in mandible morphology from birth that were amplified by different postnatal growth trajectories. Different corpus proportions and regional variation in corpus growth rates helped create space in a timely way for the molars. Regional corpus growth rates may evolve alongside permanent molar morphology and developmental timing to modify space available in the corpus for these teeth. PMID:22567294

Boughner, Julia C.

2011-01-01

203

Bovine ephemeral fever: a review  

Microsoft Academic Search

Bovine ephemeral fever is a viral disease of cattle and buffaloes besides subclinical involvement of a variety of ruminant species. The subtropical and temperate regions of Africa, Asia and Australia have experienced the major epidemic of the bovine ephemeral fever but the occurrence in the tropics can not be overlooked. Although the substantial role played by the vectors viz., mosquitoes

S Nandi; B. S Negi

1999-01-01

204

Orthodontics Align Crooked Teeth and Boost Self-Esteem  

MedlinePLUS

... as comprehensive as orthodontics. Space maintainers help maintain space for adult teeth and can prevent complications and the need for more orthodontic therapy. Removable computer-generated appliances can treat selective cases ...

205

Can Pacifiers and Baby Bottles Ruin My Baby's Teeth?  

MedlinePLUS

... Baby's Teeth? Are Pacifiers a Problem? Early Childhood Tooth Decay: The Roles of the Bottle and Breastfeeding Long- ... water. This will increase your child's risk of tooth decay. Use positive reinforcement to encourage older children to ...

206

From molecules to mastication: the development and evolution of teeth.  

PubMed

Teeth are unique to vertebrates and have played a central role in their evolution. The molecular pathways and morphogenetic processes involved in tooth development have been the focus of intense investigation over the past few decades, and the tooth is an important model system for many areas of research. Developmental biologists have exploited the clear distinction between the epithelium and the underlying mesenchyme during tooth development to elucidate reciprocal epithelial/mesenchymal interactions during organogenesis. The preservation of teeth in the fossil record makes these organs invaluable for the work of paleontologists, anthropologists, and evolutionary biologists. In addition, with the recent identification and characterization of dental stem cells, teeth have become of interest to the field of regenerative medicine. Here, we review the major research areas and studies in the development and evolution of teeth, including morphogenesis, genetics and signaling, evolution of tooth development, and dental stem cells. PMID:24009032

Jheon, Andrew H; Seidel, Kerstin; Biehs, Brian; Klein, Ophir D

2013-01-01

207

Artificial teeth : dental biofilm analysis on a chip  

E-print Network

In this thesis, an "artificial teeth" microfluidic device is developed that provides unprecedented control over the conditions required to simulate the growth of complex dental biofilm. Dental plaque formation is not only ...

Lam, Raymond Hiu-wai

2010-01-01

208

Evolutionary modification of development in mammalian teeth: Quantifying gene  

E-print Network

Evolutionary modification of development in mammalian teeth: Quantifying gene expression patterns Geographic Information Systems. We investi- gated how genetic markers for epithelial signaling centers known, usually involve little initial modification of morphology. One system that offers promise for linking

Jernvall, Jukka

209

Microstructure and chemical composition of fossil mammalian teeth  

Microsoft Academic Search

Summary  Sectioned Cretaceous mammalian teeth were studied by light microscopy and SEM equipment with an electron microprobe. Structures\\u000a resembling odontoblast processes were found. Their S\\/Fe ratio was similar to that of rat odontoblast processes, but the amounts\\u000a of these elements were far higher than in processes of recent teeth. It was concluded that they consisted of pyrite, but their\\u000a reaction with

G. Fosse; N.-P. B. Justesen; G. B. R. Wesenberg

1981-01-01

210

Nanostructure and nano-mechanical properties of human teeth  

Microsoft Academic Search

In this study, we investigate the nanostructure and nano-mechanical properties of human teeth. A nano-indenter is adopted to acquire the nano-mechanical properties of teeth, while a focused ion beam system (FIB) is used to prepare high quality transmission electron microscopy specimen. For nanomechanical properties, the tooth specimens are cut into horizontal and vertical sections separately within 1mm thick. All the

Chung-Jen Chung; Bo-Hsiung Wu; Jen-Fin Lin; Chang-Fu Han; Shu-Fen Chuang; Wang-Long Li

2011-01-01

211

First Fossil Evidence for the Advance of Replacement Teeth Coupled with Life History Evolution along an Anagenetic Mammalian Lineage  

PubMed Central

In mammals that grow up more slowly and live longer, replacement teeth tend to appear earlier in sequence than in fast growing mammals. This trend, known as ‘Schultz's Rule’, is a useful tool for inferring life histories of fossil taxa. Deviations from this rule, however, suggest that in addition to the pace of life history, ecological factors may also drive dental ontogeny. Myotragus balearicus is an extinct insular caprine that has been proved to be an excellent test case to correlate morphological traits with life history. Here we show that Myotragus balearicus exhibits a slow signature of dental eruption sequence that is in agreement with the exceptionally slow life history of this species, thus conforming to ‘Schultz's Rule’. However, our results also show an acceleration of the absolute pace of development of the permanent incisors in relation to that of the posterior teeth. The rodent-like incisors of Myotragus balearicus erupted early not only in relative but also in absolute terms (chronological age), suggesting that feeding characteristics also plays an important role in dental ontogeny. This is in agreement with ecological hypotheses based on primates. Our study documents a decoupling of the pace of development of teeth in mammals that is triggered by different selection pressures on dental ontogeny. Moreover, we show that Myotragus kopperi from the early Pleistocene (a direct ancestor of the late Pleistocene-Holocene M. balearicus) follows the pattern of first incisor replacement known in living bovids. Hence, the advance in the eruption sequence of the first incisors occurs along the Myotragus evolutionary lineage over a period of about 2.5 Myr. To our knowledge, this is the first fossil evidence of an advance of the emergence of the permanent first incisor along an anagenetic mammalian lineage. PMID:23936247

Jordana, Xavier; Marin-Moratalla, Nekane; Moncunill-Sole, Blanca; Bover, Pere; Alcover, Josep Antoni; Kohler, Meike

2013-01-01

212

First fossil evidence for the advance of replacement teeth coupled with life history evolution along an anagenetic mammalian lineage.  

PubMed

In mammals that grow up more slowly and live longer, replacement teeth tend to appear earlier in sequence than in fast growing mammals. This trend, known as 'Schultz's Rule', is a useful tool for inferring life histories of fossil taxa. Deviations from this rule, however, suggest that in addition to the pace of life history, ecological factors may also drive dental ontogeny. Myotragus balearicus is an extinct insular caprine that has been proved to be an excellent test case to correlate morphological traits with life history. Here we show that Myotragus balearicus exhibits a slow signature of dental eruption sequence that is in agreement with the exceptionally slow life history of this species, thus conforming to 'Schultz's Rule'. However, our results also show an acceleration of the absolute pace of development of the permanent incisors in relation to that of the posterior teeth. The rodent-like incisors of Myotragus balearicus erupted early not only in relative but also in absolute terms (chronological age), suggesting that feeding characteristics also plays an important role in dental ontogeny. This is in agreement with ecological hypotheses based on primates. Our study documents a decoupling of the pace of development of teeth in mammals that is triggered by different selection pressures on dental ontogeny. Moreover, we show that Myotragus kopperi from the early Pleistocene (a direct ancestor of the late Pleistocene-Holocene M. balearicus) follows the pattern of first incisor replacement known in living bovids. Hence, the advance in the eruption sequence of the first incisors occurs along the Myotragus evolutionary lineage over a period of about 2.5 Myr. To our knowledge, this is the first fossil evidence of an advance of the emergence of the permanent first incisor along an anagenetic mammalian lineage. PMID:23936247

Jordana, Xavier; Marín-Moratalla, Nekane; Moncunill-Solé, Blanca; Bover, Pere; Alcover, Josep Antoni; Köhler, Meike

2013-01-01

213

A 3D HUMAN TEETH DATABASE CONSTRUCTION BASED ON A POINT-BASED SHAPE REGISTRATION  

E-print Network

A 3D HUMAN TEETH DATABASE CONSTRUCTION BASED ON A POINT-BASED SHAPE REGISTRATION H. Abdelmunim1 , D for building a 3D database for hu- man teeth. Real extracted human teeth are scanned using a cone-beam CT scanner to build. The teeth models are seg- mented from the resulting images by means of level sets

Farag, Aly A.

214

Development of larval and transformed teeth in Ambystoma mexicanum (Urodela, Amphibia): an ultrastructural study  

Microsoft Academic Search

Odontogenesis of early larval non-pedicellate teeth, late larval teeth with a more or less distinct dividing zone and fully transformed pedicellate teeth in Ambystoma mexicanum (Urodela) was studied to obtain insights into the development of differently structured teeth in lower vertebrates. Using transmission electron microscopy we investigated five developmental stages: (1) papilla; (2) bell stage (secretion of the matrix begins);

J. Wistuba; H. Greven; G. Clemen

2002-01-01

215

Permanent scatterers in SAR interferometry  

Microsoft Academic Search

Temporal and geometrical decorrelation often prevents SAR interferometry from being an operational tool for surface deformation monitoring and topographic profile reconstruction. Moreover, atmospheric disturbances can strongly compromise the accuracy of the results. The authors present a complete procedure for the identification and exploitation of stable natural reflectors or permanent scatterers (PSs) starting from long temporal series of interferometric SAR images.

Alessandro Ferretti; Claudio Prati; Fabio Rocca

2001-01-01

216

Magnetic Fields: Visible and Permanent.  

ERIC Educational Resources Information Center

Children will be able to see the concept of a magnetic field translated into a visible reality using the simple method outlined. Standard shelf paper, magnets, iron filings, and paint in a spray can are used to prepare a permanent and well-detailed picture of the magnetic field. (Author/JN)

Winkeljohn, Dorothy R.; Earl, Robert D.

1983-01-01

217

Bovine respiratory coronavirus.  

PubMed

Bovine coronaviruses (BCoVs) cause respiratory and enteric infections in cattle and wild ruminants. BCoV is a pneumoenteric virus that infects the upper and lower respiratory tract and intestine. It is shed in feces and nasal secretions and also infects the lung. BCoV is the cause of 3 distinct clinical syndromes in cattle: (1) calf diarrhea, (2) winter dysentery with hemorrhagic diarrhea in adults, and (3) respiratory infections in cattle of various ages including the bovine respiratory disease complex or shipping fever of feedlot cattle. No consistent antigenic or genetic markers have been identified to discriminate BCoVs from the different clinical syndromes. At present, there are no BCoV vaccines to prevent respiratory BCoV infections in cattle, and the correlates of immunity to respiratory BCoV infections are unknown. This article focuses on respiratory BCoV infections including viral characteristics; epidemiology and interspecies transmission; diagnosis, pathogenesis, and clinical signs; and immunity and vaccines. PMID:20619189

Saif, Linda J

2010-07-01

218

Masculinization of the eruption pattern of permanent mandibular canines in opposite sex twin girls.  

PubMed

The aim of this study is to explore the effect of prenatal androgenization on the clinical eruption of permanent teeth expressing dimorphism and bimaturism. The eruption curves of permanent teeth (except third molars), including those that make up the canine complex (permanent canines, lower first premolars), are compared among opposite sex twins (OS twins) relative to single-born boys and girls. The comparisons are made with regard to three phases of eruption (pierced mucosa, half- erupted, and completely erupted) from a cross-sectional sample of dental casts, using Kaplan-Meier survival and Cox regression analyzes. The casts were collected from 2159 school children from the US Collaborative Perinatal Project, including 39 pairs of OS-twins, of which 12 pairs (30.8%) were Euro-Americans and 27 pairs (69.2%) were of African-American ancestry. The eruption patterns of the incisors, upper first molars, and lower canines were found to be significantly masculinized (delayed) among OS twin girls. The differences in most other teeth were either not significant, or the number of observations of active eruption phases were too few, such as in the upper first molars and incisors, to yield strong evidence and meaningful results. The masculinization of the tooth eruption pattern in OS twin girls is intriguing because of the lower canine responses during puberty, as well as canine primordial formation during early fetal androgenization of their co-twin during the 8th to 14th gestational weeks. The present results offer a challenge for future research exploring tooth eruption mechanisms, and may also highlight some cases of delayed or ectopic canines, which are biased toward females. PMID:23754587

Heikkinen, Tuomo; Harila, Virpi; Tapanainen, Juha S; Alvesalo, Lassi

2013-08-01

219

Structure, attachment, replacement and growth of teeth in bluefish, Pomatomus saltatrix (Linnaeus, 1776), a teleost with deeply socketed teeth.  

PubMed

Tooth replacement poses many questions about development, pattern formation, tooth attachment mechanisms, functional morphology and the evolution of vertebrate dentitions. Although most vertebrate species have polyphyodont dentitions, detailed knowledge of tooth structure and replacement is poor for most groups, particularly actinopterygians. We examined the oral dentition of the bluefish, Pomatomus saltatrix, a pelagic and coastal marine predator, using a sample of 50 individuals. The oral teeth are located on the dentary and premaxillary bones, and we scored each tooth locus in the dentary and premaxillary bones using a four-part functional classification: absent (A), incoming (I), functional (F=fully ankylosed) or eroding (E). The homodont oral teeth of Pomatomus are sharp, deeply socketed and firmly ankylosed to the bone of attachment. Replacement is intraosseus and occurs in alternate tooth loci with long waves of replacement passing from rear to front. The much higher percentage of functional as opposed to eroding teeth suggests that replacement rates are low but that individual teeth are quickly lost once erosion begins. Tooth number increases ontogenetically, ranging from 15-31 dentary teeth and 15-39 premaxillary teeth in the sample studied. Teeth increase in size with every replacement cycle. Remodeling of the attachment bone occurs continuously to accommodate growth. New tooth germs originate from a discontinuous dental lamina and migrate from the lingual (dentary) or labial (premaxillary) epithelium through pores in the bone of attachment into the resorption spaces beneath the existing teeth. Pomatomus shares unique aspects of tooth replacement with barracudas and other scombroids and this supports the interpretation that Pomatomus is more closely related to scombroids than to carangoids. PMID:16351980

Bemis, William E; Giuliano, Anne; McGuire, Betty

2005-01-01

220

Longitudinal clinical and radiographic evaluation of severely intruded permanent incisors in a pediatric population.  

PubMed

Intrusion is defined as the axial dislodgment of the tooth into its socket and is considered one of the most severe types of dental trauma. This longitudinal outcome study was undertaken to evaluate clinically and radiographically severely intruded permanent incisors in a population of children and adolescents. All cases were treated between September 2003 and February 2008 in a dental trauma service. Clinical and radiographic data were collected from 12 patients (eight males and four females) that represented 15 permanent maxillary incisors. Mean age at the time of injury was 8 years and 9 months (range 7-14 years and 8 months). Mean time elapsed to follow-up was 26.6 months (range 10-51 months). The analysis of data showed that tooth intrusion was twice as frequent in males. The maxillary central incisors were the most commonly intruded teeth (93.3%), and falling at home was the main etiologic factor (60%). More than half of the cases (53.3%) were multiple intrusions, 73.3% of the intruded teeth had incomplete root formation and 66.6% of the teeth suffered other injuries concomitant to intrusion. Immediate surgical repositioning was the treatment of choice in 66.7% of the cases, while watchful waiting for the tooth to return to its pre-injury position was adopted in 33.3% of the cases. The teeth that suffered additional injuries to the intrusive luxation presented a fivefold increased relative risk of developing pulp necrosis. The immature teeth had six times more chances of presenting pulp canal obliteration that the mature teeth and a lower risk of developing root resorption. The most frequent post-injury complications were pulp necrosis (73.3%), marginal bone loss (60%), inflammatory root resorption (40%), pulp canal obliteration (26.7%) and replacement root resorption (20%). From the results of this study, it was not possible to determine whether the type immediate treatment had any influence on the appearance of sequelae like pulp necrosis and root resorption after intrusive luxation, but the existence of additional injuries and the stage of root development influenced the clinical case outcome in a negative and positive manner, respectively. PMID:19614934

Neto, José Jeová Siebra Moreira; Gondim, Juliana Oliveira; de Carvalho, Fernanda Matias; Giro, Elisa Maria Aparecida

2009-10-01

221

Langerhans cell histiocytosis: impact on the permanent dentition after an 8-year follow-up.  

PubMed

Langerhans cell histiocytosis (LCH) is a rare disorder which mainly affects children. Oral changes, such as gingival ulceration, halitosis, osseous lesions associated with tooth mobility, and early loss of primary teeth, comprise the disease's first manifestations for most patients. In the long term, dental changes may occur as a result of dental and systemic treatment. Therefore, this study's purpose is to report Langerhans cell histiocytosis' effects on the permanent dentition 8 years after diagnosis, which had been established by performing a biopsy of gingival tissue on a 3-year-old patient. PMID:18505651

Guimarães, Lizandra Ferrari; Dias, Patricia Fernanda Barros Pereira; Janini, Maria Elisa; de Souza, Ivete Pomarico Ribeiro

2008-01-01

222

PERMANENT RESIDENCE PACKET PERMANENT LABOR CERTIFICATION (REGISTERED NURSE OR PHYSICAL THERAPIST)  

E-print Network

PERMANENT RESIDENCE PACKET PERMANENT LABOR CERTIFICATION (REGISTERED NURSE OR PHYSICAL THERAPIST (PR - PERM RN OR PHYSICAL THERAPIST CATEGORY).................................................. 5....................................................................................................................... 9 EMPLOYEE FAMILY CHECKLIST & QUESTIONNAIRE

Bordenstein, Seth

223

Effect of Cigarette Smoke on Acrylic Resin Teeth  

PubMed Central

Background: The discolouration of artificial teeth, which hampers aesthetics, is one of the negative effects of cigarette smoking. Therefore, the effect of cigarette smoke on the colour stability of commercially available acrylic resin teeth needs to be evaluated for clinical success and to ascertain as to which brand has superior properties. Material and Methods: Three commercially available acrylic teeth were evaluated, after division into Group A (Premadent), Group B (Astra), and Group C (Sanyo- Dent). Selected brands were subdivided as study group and control group. Each set of acrylic resin teeth were stored in artificial saliva at 37±1°C for 24 hours. After 24 hours of immersion, the colour measurement of each tooth (T0) was performed. Second colour measurements were done after 21 days (T21) of exposure to cigarette smoke for study group and after immersion in artificial saliva for control group. All data was statistically analyzed by using Repeated Measures ANOVA and Two-way ANOVA (p<0.05). Results: Group A showed least total colour change on exposure to cigarette smoke, followed by Group B and Group C had the highest total colour change. In control group, after immersion in artificial saliva, a slight increase in total colour change was observed for all groups, which was clinically acceptable. Conclusion: Group A (crosslinked acrylic resin teeth) was more colour stable and more resistant to the discolouration which was caused by cigarette smoke, followed by Group B (crosslinked acrylic resin teeth). Group C (Non-crosslinked acrylic resin teeth) was least colour stable and most susceptible to discolouration which was caused by cigarette smoke. PMID:24179942

Patil, Seema S.; M.R., Dhakshaini; Gujjari, Anil Kumar

2013-01-01

224

The retrieval of unerupted teeth in pedodontics: two case reports  

PubMed Central

Introduction The retrieval of unerupted teeth in pedodontics is always significant to preserve the trophism of adjacent tissues, establish the correct space, provide adequate function and maintain good esthetics for the patient. The treatment plan is based on radiographic examinations and measurements, and on an accurate clinical evaluation; it aims to achieve the best treatment possible depending on the complexity of the specific case. In the most difficult clinical cases it is very important to have an early diagnosis, which is essential to plan the treatment and achieve success. In these cases, the pediatrician is in a strategic position to give an early diagnosis through a child’s medical history and by counting the child’s teeth. Case presentation This article presents two different difficult clinical cases of impacted teeth diagnosed during pediatric age, with a radiological analysis, and successfully treated with orthodontic devices designed for these specific cases. Clinical case 1 describes a 13-year-old Italian girl; clinical case 2 describes a 9-year-old Italian girl. The use of these devices achieved the desired treatment goals. The problems associated with impacted teeth and the biomechanical interventions used for these patients are discussed. Conclusions An early and careful diagnosis followed by an accurate treatment plan for the individual cases can lead to retrieval of the impacted teeth without affecting other anatomic structures and adjacent teeth. In these cases, the pediatrician is in a strategic position to give an early diagnosis through a child’s medical history and by counting the child’s teeth. PMID:25301242

2014-01-01

225

Performance improvement of permanent magnet ac motors  

E-print Network

with respect to a conventional permanent magnet synchronous machine, is also compatible with vector control algorithm. 2) A resilient current control of the five-phase permanent motor with both sinusoidal and trapezoidal back-EMF waveforms under asymmetrical...

Parsa, Leila

2005-08-29

226

Tattoos and Permanent Make-Up  

MedlinePLUS

... Inks Used in Certain Tattoo Kits Cause Infections Tattoos and Permanent Make-up Print and Share (PDF ... Risks FDA's Role Tattoo Removal Options Types of Tattoos Permanent Tattoo : A needle inserts colored ink into ...

227

21 CFR 886.4445 - Permanent magnet.  

Code of Federal Regulations, 2011 CFR

...4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove metallic foreign bodies from eye tissue. (b) Classification. Class...

2011-04-01

228

21 CFR 886.4445 - Permanent magnet.  

Code of Federal Regulations, 2010 CFR

...4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove metallic foreign bodies from eye tissue. (b) Classification. Class...

2010-04-01

229

21 CFR 886.4445 - Permanent magnet.  

...4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove metallic foreign bodies from eye tissue. (b) Classification. Class...

2014-04-01

230

21 CFR 886.4445 - Permanent magnet.  

Code of Federal Regulations, 2013 CFR

...4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove metallic foreign bodies from eye tissue. (b) Classification. Class...

2013-04-01

231

21 CFR 886.4445 - Permanent magnet.  

Code of Federal Regulations, 2012 CFR

...4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove metallic foreign bodies from eye tissue. (b) Classification. Class...

2012-04-01

232

Permanent Magnets and Magnetic Fluids  

Microsoft Academic Search

Since the discovery of the extremely high magnetocrystalline anisotropy of YCo. in 1966 there has been rapidly increasing interest in the development of cobalt-rare-earth intermetallic com­ pounds as permanent magnet materials, The observed coercive forces are still only a small fraction of the anisotropy fields, and for some reason the coercive forces attainable with SmCo. are, larger than in other

J. J. BECKER

233

Planar high energy permanent magnets  

Microsoft Academic Search

Samarium-cobalt permanent magnets were fabricated by arc plasma spraying in order to evaluate this technique as an economical method for fabricating cobalt-rare earth magnets for advanced traveling wave tubes and crossfield amplifiers. Bar magnets were produced having a coercive force of 6100 oersteds and an energy product of 10.8 million gauss-oersted. The magnetic properties in bar magnets were significantly better

M. C. Willson; R. J. Janowiecki

1975-01-01

234

High-performance permanent magnets  

Microsoft Academic Search

High-performance permanent magnets (pms) are based on compounds with outstanding intrinsic magnetic properties as well as\\u000a on optimized microstructures and alloy compositions. The most powerful pm materials at present are RE–TM intermetallic alloys\\u000a which derive their exceptional magnetic properties from the favourable combination of rare earth metals (RE=Nd, Pr, Sm) with\\u000a transition metals (TM=Fe, Co), in particular magnets based on

D. Goll; H. Kronmüller

2000-01-01

235

Bounded Memory and Permanent Reputations  

Microsoft Academic Search

A recent result in reputation games is that after an arbitrarily long history, any equilibrium of the continuation game must be an equilibrium of the complete information game. We show that for two-by-two zero-sum games with incomplete information, bounded memory may lead to permanent reputations. In fact, we show that if the game is su¢ ciently noisy, a bounded memory

DANIEL MONTE

236

From molecules to mastication: the development and evolution of teeth  

PubMed Central

Teeth are unique to vertebrates and have played a central role in their evolution. The molecular pathways and morphogenetic processes involved in tooth development have been the focus of intense investigation over the past few decades, and the tooth is an important model system for many areas of research. Developmental biologists have exploited the clear distinction between the epithelium and the underlying mesenchyme during tooth development to elucidate reciprocal epithelial/mesenchymal interactions during organogenesis. The preservation of teeth in the fossil record makes these small organs essential for the work of paleontologists, anthropologists, and evolutionary biologists. In addition, with the recent identification and characterization of dental stem cells, teeth have become of interest to the field of regenerative medicine. Here, we review the major research areas and studies in the development and evolution of teeth, including morphogenesis, genetics and signaling, evolution of tooth development, and dental stem cells. Brief discussions of microRNAs and human disease as they apply to teeth are also included. PMID:24009032

Jheon, Andrew H.; Seidel, Kerstin; Biehs, Brian; Klein, Ophir D.

2012-01-01

237

Photoacoustic diagnosis of human teeth using interferometric detection scheme  

NASA Astrophysics Data System (ADS)

We have investigated the mechanical and acoustic properties of human teeth using the laser generation of surface acoustic wave (SAW) technique. The materials investigated included normal and decayed teeth, which have similar grain sizes and different thicknesses. The tissue responds to the laser-induced stress by thermoelastic expansion. The informative features of this method allow one to determine sample thermal, optical, and acoustical properties that depend on the peculiarities of the sample compositional structure. An interferometric detection experimental scheme is applied for detection generated SAW pulses. The surface displacement curves shape of normal and decayed human teeth are shown. The dispersion curves for SAW pulses were determined by Fourier analysis. The result is an almost linear dependence of SAW velocity on frequency for a normal tooth, the magnitude of the thermoelastic expansion of the normal tooth reaches its peak at 0.344 ?s, a SAW phase velocity of 2500 ms-1 between 0.0008 and 5 MHz was determined. For abnormal teeth, the magnitude of thermoelastic expansion of the normal tooth reaches its peak at 1.3 ?s, the measured velocity was 3225 ms-1. Due to the inhomogeneity of abnormal teeth perpendicular to the propagation direction, strong differences in their dispersion curves were obtained. The detection of acoustic waves is the basis of photoacoustic methods, which can be used for diagnostic purposes.

El-Sharkawy, Yasser H.; El Sherif, Ashraf F.

2012-07-01

238

Near-IR imaging of cracks in teeth  

NASA Astrophysics Data System (ADS)

Dental enamel is highly transparent at near-IR wavelengths and several studies have shown that these wavelengths are well suited for optical transillumination for the detection and imaging of tooth decay. We hypothesize that these wavelengths are also well suited for imaging cracks in teeth. Extracted teeth with suspected cracks were imaged at several wavelengths in the near-IR from 1300-1700-nm. Extracted teeth were also examined with optical coherence tomography to confirm the existence of suspected cracks. Several teeth of volunteers were also imaged in vivo at 1300-nm to demonstrate clinical potential. In addition we induced cracks in teeth using a carbon dioxide laser and imaged crack formation and propagation in real time using near-IR transillumination. Cracks were clearly visible using near-IR imaging at 1300-nm in both in vitro and in vivo images. Cracks and fractures also interfered with light propagation in the tooth aiding in crack identification and assessment of depth and severity.

Fried, William A.; Simon, Jacob C.; Lucas, Seth; Chan, Kenneth H.; Darling, Cynthia L.; Staninec, Michal; Fried, Daniel

2014-02-01

239

Building trust on bovine TB.  

PubMed

Opinion on how best to control bovine TB remains divided, particularly with regard to badgers. Rosie Woodroffe believes that vets have a constructive role to play in the debate and helping farmers locally. PMID:24736823

Woodroffe, Rosie

2014-03-01

240

The optimal design of involute gear teeth with unequal addenda  

NASA Technical Reports Server (NTRS)

The design of a gear mesh is treated with the objective of minimizing the gear size for a given gear ratio, pinion torque, pressure angle, and allowable tooth lengths. Tooth strengths considered include scoring, pitting fatigue, and bending fatigue. Kinematic involute interference is avoided. The design variation on standard spur gear teeth called the long and short addendum system, is considered. In this system the mesh center distance and pressure angle are maintained as is the ability to manufacture the teeth with standard tooling. However, the pinion and gear tooth proportions are altered in order to obtain fewer teeth numbers for the same ratio as standard gears without kinematic involute interference. The effect of this nonstandard gearing geometry with on tooth strengths and gear mesh size are studied. For a 2:1 gearing ratio, the optimal nonstandard gear design is compared with the optimal standard gear design.

Savage, M.; Coy, J. J.; Townsend, D. P.

1982-01-01

241

Methods for physical stabilization of ashed teeth in incinerated remains.  

PubMed

Methods for physically stabilizing the extremely fragile ashed teeth that are often encountered in incinerated human remains were investigated. Results of a questionnaire sent to forensic anthropologists and forensic odontologists disclosed that, for these two groups, the most popular methods currently used are impregnation with a solution of polyvinyl acetate or application of cyanoacrylate cement, respectively. In addition, extracted human teeth were incinerated in the laboratory and impregnated with commercially available preparations of either cyanoacrylate cement, clear acrylic spray paint, hair spray, spray furniture varnish, clear fingernail polish, quick-setting epoxy cement, Duco household cement, polyvinyl acetate polymer in acetone, or self-curing clear dental acrylic resin. Every substance tested successfully stabilized the incinerated teeth. Clear acrylic spray paint was judged the most efficacious overall because of its ease of application, availability, inexpensiveness, and rapidity of setting. PMID:2391485

Mincer, H H; Berryman, H E; Murray, G A; Dickens, R L

1990-07-01

242

Identifying individuals by sequencing mitochondrial DNA from teeth.  

PubMed

Mitochondrial DNA (mtDNA) was extracted from teeth stored from 3 months to 20 years, including teeth from the semi-skeletonized remains of a murder victim which had been buried for 10 months. Tooth donors and/or their maternal relatives provided blood or buccal cells, from which mtDNA was also extracted. Enzymatic amplification and direct sequencing of roughly 650 nucleotides from two highly polymorphic regions of mtDNA yielded identical sequences for each comparison of tooth and fresh DNA. Our results suggest that teeth provide an excellent source for high molecular weight mtDNA that can be valuable for extending the time in which decomposed human remains can be genetically identified. PMID:1303263

Ginther, C; Issel-Tarver, L; King, M C

1992-10-01

243

The Shape Design of Permanent Magnet for Permanent Magnet Synchronous Motor Considering Partial Demagnetization  

Microsoft Academic Search

This paper presents a study on shape design of permanent magnets that is focused on robustness for cogging torque, sinusoidal back emf, and partial demagnetization of the permanent magnet of the outer rotor permanent magnet synchronous motor (PMSM). The simulation method for partial demagnetization is proposed and performed with four kinds of permanent magnet shape models at the fault current

Ki-Chan Kim; Seung-Bin Lim; Dae-Hyun Koo; Ju Lee

2006-01-01

244

Organic Matrix-related mineralization of sea urchin spicules, spines, test and teeth  

PubMed Central

The camarodont echinoderms have five distinct mineralized skeletal elements: the embryonic spicules and mature test; spines, lantern stereom and teeth. The embryonic spicules are transient structural elements of the larval skeleton whereas the spines and test plates are permanent structural elements. The teeth are continuously growing structures, matching wear at the incisal adoral end to the rate of new production at the aboral plumula. The mineral in all cases is a high magnesium calcite, but the magnesium content, crystal shape and growth pattern is different in each type of skeletal element. The crystal shape and organization into macro structures depends on the presence of an organic matrix which creates the spaces and controls the environments for crystal initiation and growth. The detailed mechanisms of crystal regulation are not known, but much work has been done on defining the proteins which appear to be involved. Phosphorylated matrix proteins may be of special importance. Biochemical isolation of proteins, construction and analysis of cDNA libraries, and most recently high-throughput proteomic analysis in conjunction with the sequencing of the complete genome have yielded a detailed list of protein components likely to be involved in the mineralization processes. However, the proteome-genome analyses have not yet provided insight into the mechanisms of crystallization, calcite composition, and orientation applicable to all skeletal elements. Although the embryonic pluteus and their spicules are the best studied system, it appears that spicule is not representative of the mature skeletal elements. Now armed with the compositions of most of the proteins involved, the next phase of research will have to focus on the specific localization of the proteins and individual biochemistries of each system with regard to mineral content and placement. PMID:21622194

Veis, Arthur

2012-01-01

245

Permanent-File-Validation Utility Computer Program  

NASA Technical Reports Server (NTRS)

Errors in files detected and corrected during operation. Permanent File Validation (PFVAL) utility computer program provides CDC CYBER NOS sites with mechanism to verify integrity of permanent file base. Locates and identifies permanent file errors in Mass Storage Table (MST) and Track Reservation Table (TRT), in permanent file catalog entries (PFC's) in permit sectors, and in disk sector linkage. All detected errors written to listing file and system and job day files. Program operates by reading system tables , catalog track, permit sectors, and disk linkage bytes to vaidate expected and actual file linkages. Used extensively to identify and locate errors in permanent files and enable online correction, reducing computer-system downtime.

Derry, Stephen D.

1988-01-01

246

Tetracycline-Induced Discoloration of Deciduous Teeth: Case Series  

PubMed Central

Tetracycline was the choice of antibiotic in some of the life-threatening bacterial infections. Due to its adverse effects and ability to cross-placental barrier, its use is contraindicated in pregnancy and in children. This is a case series of four patients with tetracycline-induced discoloration in primary teeth. How to cite the article: Vennila V, Madhu V, Rajesh R, Ealla KKR, Velidandla SR, Santoshi S. Tetracycline induced discoloration of deciduous teeth: Case series. J Int Oral Health 2014;6(3):115-9. PMID:25083046

Vennila, Vijayasree; Madhu, Vasapalli; Rajesh, R; Ealla, Kranti Kiran Reddy; Velidandla, Surekha Reddy; Santoshi, S

2014-01-01

247

Odontomas and Supernumerary Teeth: Is There a Common Origin?  

PubMed Central

The aim of the present work is to analyze all scientific evidence to verify whether similarities supporting a unified explanation for odontomas and supernumerary teeth exist. A literature search was first conducted for epidemiologic studies indexed by PubMed, to verify their worldwide incidence. The analysis of the literature data shows some interesting similarities between odontomas and supernumerary teeth concerning their topographic distribution and pathologic manifestations. There is also some indication of common genetic and immuno-histochemical factors. Although from a nosological point of view, odontomas and supernumeraries are classified as distinct entities, they seem to be the expression of the same pathologic process, either malformative or hamartomatous.

Pippi, Roberto

2014-01-01

248

Scanning electron microscopy and electron probe X-ray microanalysis (SEM-EPMA) of pink teeth  

SciTech Connect

Samples of postmortem pink teeth were investigated by scanning electron microscopy and electron probe X-ray microanalysis. Fracture surfaces of the dentin in pink teeth were noticeably rough and revealed many more smaller dentinal tubules than those of the control white teeth. Electron probe X-ray microanalysis showed that the pink teeth contained iron which seemed to be derived from blood hemoglobin. The present study confirms that under the same circumstance red coloration of teeth may occur more easily in the teeth in which the dentin is less compact and contains more dentinal tubules.

Ikeda, N.; Watanabe, G.; Harada, A.; Suzuki, T.

1988-11-01

249

Method of making permanent magnets  

DOEpatents

A method for making an isotropic permanent magnet comprises atomizing a melt of a rare earth-transition metal alloy (e.g., an Nd--Fe--B alloy enriched in Nd and B) under conditions to produce protectively coated, rapidly solidified, generally spherical alloy particles wherein a majority of the particles are produced/size classified within a given size fraction (e.g., 5 to 40 microns diameter) exhibiting optimum as-atomized magnetic properties and subjecting the particles to concurrent elevated temperature and elevated isotropic pressure for a time effective to yield a densified, magnetically isotropic magnet compact having enhanced magnetic properties and mechanical properties.

McCallum, R. William (Ames, IA); Dennis, Kevin W. (Ames, IA); Lograsso, Barbara K. (Ames, IA); Anderson, Iver E. (Ames, IA)

1993-09-07

250

Occlusal caries diagnosis in permanent teeth: an in vitro study Diagnóstico de cárie oclusal em dentes permanentes: estudo in vitro  

Microsoft Academic Search

The reduction in caries prevalence has not occurred uniformly for all dental surfaces. As the occlusal surfaces are still the most likely sites for the development of lesions, new methods of diagnosis are still being evalu- ated. This study compared a laser fluorescence (LF) system (DIAGNOdent) with the Ekstrand's visual system for in vitro detection of occlusal caries. A total

Braz Oral Res; Gisele Angnes; Vivian Angnes; Rosa Helena; Miranda Grande; Márcio Battistella; Alessandro Dourado Loguercio; Alessandra Reis

251

Psychological effects of permanently implanted false teeth: A 2-year follow-up and comparison with dentate patients  

Microsoft Academic Search

The treatment of patients who have suffered total tooth loss (edentulism) has always posed many problems in dental care, since removable dentures cannot restore function completely and can often result in pain and mouth ulcers. An important recent advance is the development of “osseointegrated implants”. This technique involves the insertion of titanium screws into the jawbone and the denture is

Gerry Kent; Richard Johns

1993-01-01

252

Ankylosis of traumatized permanent incisors: pathogenesis and current approaches to diagnosis and management.  

PubMed

Ankylosis is a known complication of replanted or severely intruded permanent incisors and can be diagnosed by the characteristic sound emitted when the tooth is tapped. The ankylosed incisor demonstrates a lack of physiologic mobility and, later, radiographic evidence of replacement resorption. If the patient is pre-adolescent or adolescent at the time of trauma, infraocclusion relative to adjacent teeth will become apparent during jaw growth. Despite considerable knowledge about the pathogenesis of ankylosis garnered from animal studies and observation of human replanted teeth, there is no known treatment to arrest this condition. Management techniques and rehabilitation options for addressing ankylosis and its consequences are supported by little evidence, do not appear to be widely adopted and do not offer any proven long-term benefit. Avulsion and severe intrusion of permanent incisors are rare injuries. Should the decision be made to intervene by replantation or reduction of the intrusion, the clinician must be prepared to diagnose ankylosis, identify its negative consequences and develop treatment plans accordingly. PMID:16324230

Campbell, Karen M; Casas, Michael J; Kenny, David J

2005-11-01

253

Dental caries in primary and permanent molars in 7-8-year-old schoolchildren evaluated with Caries Assessment Spectrum and Treatment (CAST) index  

PubMed Central

Background No reports on a caries pattern covering the full spectrum of the disease could be found in the literature. The aim of this study was to evaluate caries in primary and first permanent molars of 7-8-year-old Polish children by the Caries Assessment Spectrum and Treatment (CAST) index and to find whether there was any correlation between the caries stages in such teeth. Methods The study covered 284 7-8-year-old children from randomly selected schools in the Bialystok District, Poland. The prevalence of CAST categories was evaluated with regard to the first and second primary, and first permanent, molars. The Spearman’s rank correlation coefficient was used to explore the correlation of the distribution of CAST codes among the evaluated teeth. The level of statistical significance was established at p?permanent molars, caries was observed in 14.8% to 17.3% of the molar and most lesions were scored at the non-cavitation level. Caries in primary molars was most often recorded at the stage of cavitated dentine lesion. Teeth with pulpal involvement, sepsis and extracted due to caries were found to be more prevalent in first, and then in second primary molars. A strong correlation was found between the status of teeth from the right and left sides of the oral cavity. The correlation of the status of first and second primary teeth was stronger for the left than for the right side of the mouth, r was 0.627 and 0.472 in maxilla and 0.513 and 0.483 in mandible (p?permanent molars the correlation was assessed to be weak. With regard to the teeth situated in opposite jaws the study revealed that the correlations were moderate - r between 0.33 and 0.49. The intra-examiner reliability was established at 0.96 for the primary dentition and at 0.878 for permanent molars. Conclusion The strongest correlation found in the evaluated population concerned the distribution of caries in primary molars on the left side of the mouth. The study proved the usefulness of the CAST index in epidemiological surveys. PMID:24952612

2014-01-01

254

Force microscopical investigation of human teeth in liquids  

Microsoft Academic Search

We observed and quantified the structural changes of the enamel of human teeth under the influence of some commonly consumed soda pops of pH 4 to pH 5. In order to observe the onset of structural changes, we developed a device allowing a fast exchange of the liquid medium covering the sample in a scanning force microscope during image acquisition.

O. Sollbohmer; K.-P. May; M. Anders

1995-01-01

255

Dentinal anomalies in teeth of harbour porpoises (Phocoena phocoena) from  

E-print Network

factors that affect the general health of the individual (e.g. persistent organic pollutant (POPDentinal anomalies in teeth of harbour porpoises (Phocoena phocoena) from Scottish waters, Department of Zoology, Ecology and Plant Science, University College, National University of Ireland, Lee

Pierce, Graham

256

Specialized stem cell niche enables repetitive renewal of alligator teeth  

E-print Network

goal here is to identify stem cells that can be used as a resource for episodic tooth renewal. DentalSpecialized stem cell niche enables repetitive renewal of alligator teeth Ping Wua , Xiaoshan Wua lamina. Using multiple mitotic labeling, we map putative stem cells to the distal enlarged bulge

Chuong, Cheng-Ming

257

Case of idiopathic loss of deciduous teeth and associated alveolus.  

PubMed

We describe exfoliation of the lower left deciduous canine and deciduous first molar (CD) and associated alveolus of unknown cause in a 5-year-old healthy boy. Extraction of the teeth and removal of local bone led to healing without complication. PMID:22019024

Koshal, Sonita; Chaudhry, Shahid I; Johnson, Adele; Porter, Stephen

2012-07-01

258

Characterization of crocodile teeth: correlation of composition, microstructure, and hardness.  

PubMed

Structure and composition of teeth of the saltwater crocodile Crocodylus porosus were characterized by several high-resolution analytical techniques. X-ray diffraction in combination with elemental analysis and infrared spectroscopy showed that the mineral phase of the teeth is a carbonated calcium-deficient nanocrystalline hydroxyapatite in all three tooth-constituting tissues: Dentin, enamel, and cementum. The fluoride content in the three tissues is very low (<0.1 wt.%) and comparable to that in human teeth. The mineral content of dentin, enamel, and cementum as determined by thermogravimetry is 71.3, 80.5, and 66.8 wt.%, respectively. Synchrotron X-ray microtomography showed the internal structure and allowed to visualize the degree of mineralization in dentin, enamel, and cementum. Virtual sections through the tooth and scanning electron micrographs showed that the enamel layer is comparably thin (100-200 ?m). The crystallites in the enamel are oriented perpendicularly to the tooth surface. At the dentin-enamel-junction, the packing density of crystallites decreases, and the crystallites do not display an ordered structure as in the enamel. The microhardness was 0.60±0.05 GPa for dentin, 3.15±0.15 GPa for enamel, 0.26±0.08 GPa for cementum close to the crown, and 0.31±0.04 GPa for cementum close to the root margin. This can be explained with the different degree of mineralization of the different tissue types and is comparable with human teeth. PMID:24091039

Enax, Joachim; Fabritius, Helge-Otto; Rack, Alexander; Prymak, Oleg; Raabe, Dierk; Epple, Matthias

2013-11-01

259

Influence of Certain Variables on the Stresses in Gear Teeth  

Microsoft Academic Search

A photoelastic study was made to obtain a more accurate picture of the localized stresses in gear tooth fillets than can be obtained from the commonly used Lewis equation. A set of approximate stress concentration factors are presented for fillets in gear teeth based upon a set of variables such as the radius r of the fillets, thickness t of

Thomas J. Dolan

1941-01-01

260

Root fillings with Endoflas in primary teeth: a retrospective study.  

PubMed

The aim of this retrospective study is to report the success rate of root canal treatments (RCT) using Endoflas as a filling material in primary teeth. Fifty-five (55 teeth, 27 maxillary incisors and 28 molars) of 47 children fulfilled the criteria to be included in the study. The immediate post-operative radiograph was evaluated and the root filling was rated overfilled, flush or underfilled. Thirty-one (31) teeth were overfilled; of these 9 (29%) were normal pre-operatively and the remaining 22 (71%) presented with bone pathology. Twenty-four (24) teeth were flush or underfilled; of these, 50% had preoperative bone pathology. The children were examined clinically and radiographically at follow-up visits ranging from 6 to 52 months. Approximately 70% of the cases were successful at the last followup examination. The remaining 30% presented with pathology (Po); however, only one tooth had to be extracted (Pi). Overfilling led to a success rate of 58%, while in the combined flush and underfilled the success rate was 83%. PMID:12413171

Fuks, Anna B; Eidelman, Eliezer; Pauker, Nitay

2002-01-01

261

Determination of some cationic species in temporary teeth  

Microsoft Academic Search

Some cationic species (Ca, Mg, Sr, Cu, Zn and Pb) have been determined in temporary teeth (n = 67) sampled from a children population living in Mérida, Venezuela, with a mean age of 87.76 ± 34.50 months within a range from 29 to 151 months. Each powdered tooth sample was analyzed for calcium, magnesium, strontium and zinc and for copper

Elias Burguera; Ziary Romero; Marcela Burguera; José Luis Burguera; Hella de Arenas; Carlos Rondon; Maria Luisa di Bernado

2002-01-01

262

Teeth of Embryos in Lamniform Sharks (Chondrichthyes: Elasmobranchii)  

Microsoft Academic Search

The dentitions of lamniform sharks possess a unique heterodonty, the lamnoid tooth pattern. However, in embryos, there are 'embryonic' and 'adult' dentitions. The teeth in the embryonic dentition are peg-like and appear to be attached to the jaw in an acrodont fashion. The adult dentition is characterized by the presence of replacement tooth series with the lamnoid tooth pattern. The

Kenshu Shimada

2002-01-01

263

Newly recognized Pleistocene human teeth from Tabun Cave, Israel  

Microsoft Academic Search

Seven human teeth from Tabun Cave, Israel, curated at the Natural History Museum London since 1955, are of uncertain provenance and identity. They are all from the upper dentition, without duplications, and are characterized by a similar preservation. The Catalogue of Fossil Hominids (1975) suggested that they might have derived from Tabun Layer A (Bronze Age to Recent). However, one

Alfredo Coppa; Rainer Grün; Chris Stringer; Stephen Eggins; Rita Vargiu

2005-01-01

264

Accuracy of age estimation of radiographic methods using developing teeth  

Microsoft Academic Search

Developing teeth are used to assess maturity and estimate age in a number of disciplines, however the accuracy of different methods has not been systematically investigated. The aim of this study was to determine the accuracy of several methods. Tooth formation was assessed from radiographs of healthy children attending a dental teaching hospital. The sample was 946 children (491 boys,

M. Maber; H. M. Liversidge; M. P. Hector

2006-01-01

265

Detection of bovine viruses in fetal bovine serum used in cell culture  

Microsoft Academic Search

Summary  This investigation employed a viral screening method to detect endogenous bovine virus contaminants in commercially supplied\\u000a fetal bovine serum.\\u000a \\u000a Fifty-one lots of fetal bovine serum from 14 suppliers were examined. Over 30% of the lots tested were found to contain bovine\\u000a viruses; they included bovine virus diarrhea virus, parainfluenza type 3-like virus, bovine herpesvirus-1, bovine enterovirus\\u000a type 4, and an

A. J. Kniazeff; L. J. Wopschall; H. E. Hopps; C. S. Morris

1975-01-01

266

Genetics Home Reference: Short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething ...  

MedlinePLUS

... disorder catalog Conditions > Short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay (often shortened to ... is SHORT syndrome? Short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay, commonly known by ...

267

Hen's teeth with enamel cap: from dream to impossibility  

PubMed Central

Background The ability to form teeth was lost in an ancestor of all modern birds, approximately 100-80 million years ago. However, experiments in chicken have revealed that the oral epithelium can respond to inductive signals from mouse mesenchyme, leading to reactivation of the odontogenic pathway. Recently, tooth germs similar to crocodile rudimentary teeth were found in a chicken mutant. These "chicken teeth" did not develop further, but the question remains whether functional teeth with enamel cap would have been obtained if the experiments had been carried out over a longer time period or if the chicken mutants had survived. The next odontogenetic step would have been tooth differentiation, involving deposition of dental proteins. Results Using bioinformatics, we assessed the fate of the four dental proteins thought to be specific to enamel (amelogenin, AMEL; ameloblastin, AMBN; enamelin, ENAM) and to dentin (dentin sialophosphoprotein, DSPP) in the chicken genome. Conservation of gene synteny in amniotes allowed definition of target DNA regions in which we searched for sequence similarity. We found the full-length chicken AMEL and the only N-terminal region of DSPP, and both are invalidated genes. AMBN and ENAM disappeared after chromosomal rearrangements occurred in the candidate region in a bird ancestor. Conclusion These findings not only imply that functional teeth with enamel covering, as present in ancestral Aves, will never be obtained in birds, but they also indicate that these four protein genes were dental specific, at least in the last toothed ancestor of modern birds, a specificity which has been questioned in recent years. PMID:18775069

2008-01-01

268

DISTRIBUTION OF BOVINE LEUKEMIA VIRUS PROVIRAL SEQUENCES IN TISSUES OF BOVINE,  

E-print Network

in 0.01 M Tris-HCI buffer,LpH 8.3. Animal and human tissues. Bovine and ovine tissues were collectedDISTRIBUTION OF BOVINE LEUKEMIA VIRUS PROVIRAL SEQUENCES IN TISSUES OF BOVINE, OVINE AND HUMAN. Après recyclage avec du DNA de bovin normal, le (3H) cDNA de BLV hybride au DNA de tumeur de bovin

Paris-Sud XI, Université de

269

Cusp fracture of endodontically treated posterior teeth restored with amalgam. Teeth restored in Denmark before 1975 versus after 1979.  

PubMed

The aim of the present study was to analyze the frequency and the severity of cuspal fracture for posterior teeth endodontically treated by 91 Danish dentists and restored with amalgam either before 1975 or after 1979. A database from a previous study was analyzed (1584 teeth with an MO, a DO, or an MOD amalgam restoration without cuspal overlays). Teeth restored before 1975 had a significantly lower frequency of cusp fracture than teeth restored after 1979. Moreover, when comparing the frequency of subcrestal fractures, that of the second group (after 1979) was more than twice as high as that of the first group (before 1975). Two factors with a bearing on these findings changed in the time period 1975-1979; the high-copper amalgams took over in Denmark, and the use of Gates-Glidden burs to achieve straight-line access to the root canal was introduced. It is suggested that the weakening of the coronal part of the root, caused by the use of Gates-Glidden burs, and the expansion and low creep of high-copper amalgams may be two of the reasons for the increased frequency and severity of cuspal fracture found in the past decade in Denmark. PMID:8498164

Hansen, E K; Asmussen, E

1993-04-01

270

E- and N-Cadherin Distribution in Developing and Functional Human Teeth under Normal and Pathological Conditions  

PubMed Central

Cadherins are calcium-dependent cell adhesion molecules involved in the regulation of various biological processes such as cell recognition, intercellular communication, cell fate, cell polarity, boundary formation, and morphogenesis. Although previous studies have shown E-cadherin expression during rodent or human odontogenesis, there is no equivalent study available on N-cadherin expression in dental tissues. Here we examined and compared the expression patterns of E- and N-cadherins in both embryonic and adult (healthy, injured, carious) human teeth. Both proteins were expressed in the developing teeth during the cap and bell stages. E-cadherin expression in dental epithelium followed an apical-coronal gradient that was opposite to that observed for N-cadherin. E-cadherin was distributed in proliferating cells of the inner and outer enamel epithelia but not in differentiated cells such as ameloblasts, whereas N-cadherin expression was up-regulated in differentiated epithelial cells. By contrast to E-cadherin, N-cadherin was also expressed in mesenchymal cells that differentiate into odontoblasts and produce the hard tissue matrix of dentin. Although N-cadherin was not detected in permanent intact teeth, it was re-expressed during dentin repair processes in odontoblasts surrounding carious or traumatic sites. Similarly, N-cadherin re-expression was seen in vitro, in cultured primary pulp cells that differentiate into odontoblast-like cells. Taken together these results suggest that E- and N-cadherins may play a role during human tooth development and, moreover, indicate that N-cadherin is important for odontoblast function in normal development and under pathological conditions. PMID:12057916

Heymann, Robert; About, Imad; Lendahl, Urban; Franquin, Jean-Claude; Obrink, Bjorn; Mitsiadis, Thimios A.

2002-01-01

271

Gating of Permanent Molds for Aluminum Casting  

Microsoft Academic Search

This report summarizes a two-year project, DE-FC07-011D13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was to determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity

David Schwam; John F. Wallace; Tom Engle; Qingming Chang

2004-01-01

272

Permanent magnets for self-regulating generators  

Microsoft Academic Search

Self-regulating permanent magnet generators (PMGs) apply rare earth magnets for providing excitation during their operation.\\u000a This paper explains the operating principle of the self-regulating PMG and correlates the performance requirements with the\\u000a characteristics of rare earth permanent magnets. The dynamic operation under load, overload, and short circuit conditions\\u000a is reviewed; and the effect on the magnetic characteristics of the permanent

Mahesh J. Shah; Jayant G. Vaidya

1991-01-01

273

Edinburgh Research Explorer Small Theropod Teeth from the Late Cretaceous of the San Juan  

E-print Network

Edinburgh Research Explorer Small Theropod Teeth from the Late Cretaceous of the San Juan Basin for published version: Williamson, T & Brusatte, S 2014, 'Small Theropod Teeth from the Late Cretaceous date: 15. Sep. 2014 #12;Small Theropod Teeth from the Late Cretaceous of the San Juan Basin

Schnaufer, Achim

274

Growth of stylolite teeth patterns depending on normal stress and finite compaction  

E-print Network

Growth of stylolite teeth patterns depending on normal stress and finite compaction Daniel Koehn a. We demonstrate that the typical steep stylolite teeth geometry can accurately be modelled the roughness growth saturates. We also show that the stylolite teeth geometry tracks the main compressive

275

On the Increasing Fragility of Human Teeth With Age: A Deep-UV Resonance Raman Study  

E-print Network

On the Increasing Fragility of Human Teeth With Age: A Deep-UV Resonance Raman Study Joel W Ager vibration (amide I) becomes significantly higher when comparing teeth from donors with an average age of 23 in the UVRR spectra of both teeth and bone is surprising, given that only bone undergoes remodeling. However

Ritchie, Robert

276

An Ancient Gene Network Is Co-opted for Teeth on Old and New Jaws  

E-print Network

An Ancient Gene Network Is Co-opted for Teeth on Old and New Jaws Gareth J. Fraser1* , C. Darrin, teeth developed on oral jaws and helped to establish the dominance of this lineage on land jaw in the pharynx, the location of the first vertebrate teeth. To examine the evolutionary modularity

Hulsey, C. Darrin

277

Growth of stylolite teeth patterns depending on normal stress and1 finite compaction2  

E-print Network

- 1 - Growth of stylolite teeth patterns depending on normal stress and1 finite compaction2 3 teeth geometry can accurately be modelled and reproduce natural22 patterns. The growth of the roughness saturates. We also show that the33 stylolite teeth geometry tracks the main compressive stress direction

Boyer, Edmond

278

Biology Meets Engineering: The Structural Mechanics of Fossil and Extant Shark Teeth  

E-print Network

Biology Meets Engineering: The Structural Mechanics of Fossil and Extant Shark Teeth Lisa B, with little integration of tooth properties or function. As teeth are subjected to sometimes extreme loads processing ability and structural parameters must be considered to understand the evolu- tion of shark teeth

Motta, Philip J.

279

INTRODUCTION Dentin represents the principal load-bearing material in teeth. It is a  

E-print Network

INTRODUCTION Dentin represents the principal load-bearing material in teeth. It is a hydrated al., 2005). This suggests that dehydration by alcohol may actually strengthen teeth. Accordingly effect on the elastic modulus, strength, and fracture toughness of dentin. Although this made teeth more

Ritchie, Robert

280

A computational model of teeth and the developmental origins of morphological variation  

E-print Network

LETTERS A computational model of teeth and the developmental origins of morphological variation variation of real teeth. To model the full range of develop- mentally possible morphologies, we used the complexity of development and teeth, there may be a simple basis for dental variation. Changes in single

Jernvall, Jukka

281

XVIII. On the Forms of the Teeth of Wheels. By GEORGE BIDDELL AIRY, B.A.  

E-print Network

XVIII. On the Forms of the Teeth of Wheels. By GEORGE BIDDELL AIRY, B.A. fellow of trinity college.] The investigation of the forms proper for the teeth of wheels is a useful and interesting inquiry. The mechanical the figures which must be given to the teeth of wheels to insure uniformity of action. The curves above

Roegel, Denis

282

High-Pressure Replica Technique for In Vitro Imaging of Pore Morphologies in Teeth  

Microsoft Academic Search

The presence of a natural pore morphology is an essential factor in chemical and mechanical stability of teeth. Common histological methods give only an insufficient picture of the three-dimensional pore distribution in sound or carious teeth. This paper describes a new technique to obtain complete images of the pore structure in teeth or other biological hard tissues. Whole extracted human

H. Uchtmann; D. Wilkie

1997-01-01

283

Intracoronal bleaching of discolored non-vital teeth using laser irradiation: a case report  

Microsoft Academic Search

Dissemination of blood into the dentinal tubules caused by pulp extirpation or traumatically induced internal pulp bleeding is a possible cause of discoloration of non-vital teeth. Discolored teeth, especially in the anterior region, can result in considerable cosmetic impairment. The whitening of these teeth is an alternative therapeutic method that is relatively non-invasive and conserves dental hard tissue. Recently, intracoronal

Melissa A. Marchesan; Fabiana C. de Castro; Alexandre T. Matarazzo; Jesus D. Pecora; Fatima A. Zanin; Aldo Brugnera Jr.

2004-01-01

284

A gene network model accounting for development and evolution of mammalian teeth  

E-print Network

A gene network model accounting for development and evolution of mammalian teeth Isaac Salazar reproducing the morphology of mammalian teeth by integrating experimental data on gene inter- actions), and brain (8, 9). In addition, the morphogenesis of teeth is largely unaffected by that of adjacent organs

Jernvall, Jukka

285

Failure load of acrylic resin denture teeth bonded to high impact acrylic resins  

Microsoft Academic Search

Statement of problem. Techniques for bonding denture teeth to an acrylic resin denture base remain empirical, with little consensus from the literature, among clinicians, or among dental laboratories. Purpose. This study evaluated the failure load of acrylic resin teeth bonded to 2 high impact acrylic resins. Methods and material. The ridge lap portion on 120 identical denture teeth were modified

Donna Barpal; Donald A. Curtis; Frederick Finzen; Jovin Perry; Stuart A. Gansky

1998-01-01

286

Hydathodal leaf teeth of Chloranthus japonicus (Chloranthaceae) prevent guttation-induced flooding of the mesophyll  

Microsoft Academic Search

Why the leaves of cold temperate deciduous and moisture- loving angiosperms are so often toothed has long puzzled biologists because the functional consequences of teeth remain poorly understood. Here we provide functional and structural evidence that marginal leaf teeth of Chloranthus japonicus , an understory herb, enable the release of gutta- tion sap during root pressure. When guttation from teeth

TAYLOR S. FEILD; TAMMY L. SAGE; CHRISTINE CZERNIAK; WILLIAM J. D. ILES

2005-01-01

287

Design and analysis of new fault-tolerant permanent magnet motors for four-wheel-driving electric vehicles  

NASA Astrophysics Data System (ADS)

In this paper, a novel in-wheel permanent-magnet (PM) motor for four-wheel-driving electrical vehicles is proposed. It adopts an outer-rotor topology, which can help generate a large drive torque, in order to achieve prominent dynamic performance of the vehicle. Moreover, by adopting single-layer concentrated-windings, fault-tolerant teeth, and the optimal combination of slot and pole numbers, the proposed motor inherently offers negligible electromagnetic coupling between different phase windings, hence, it possesses a fault-tolerant characteristic. Meanwhile, the phase back electromotive force waveforms can be designed to be sinusoidal by employing PMs with a trapezoidal shape, eccentric armature teeth, and unequal tooth widths. The electromagnetic performance is comprehensively investigated and the optimal design is conducted by using the finite-element method.

Liu, Guohai; Gong, Wensheng; Chen, Qian; Jian, Linni; Shen, Yue; Zhao, Wenxiang

2012-04-01

288

Seroprevalence of bovine respiratory viruses in North-Western Turkey  

Microsoft Academic Search

Bovine respiratory disease complex is a very important health problem around the world. Present study describes serological\\u000a distribution of bovine major respiratory viruses in non -vaccinated cattle population of Marmara region in north-western Turkey.\\u000a Neutralising antibodies specific to bovine viral diarrhoea virus (BVDV), bovine herpesvirus 1 (BHV-1), bovine respiratory\\u000a syncytial virus (BRSV), bovine parainfluenza virus 3 (PI-3), bovine adenovirus serotype

Kadir Ye?ilba?; Burak Güngör

2008-01-01

289

Bovine Acidosis: Implications on Laminitis  

Microsoft Academic Search

Bovine lactic acidosis syndrome is associated with large increases of lactic acid in the rumen, which result from diets that are high in ruminally available carbohydrates, or forage that is low in effective fiber, or both. The syndrome involves two separate anatom- ical areas, the gastrointestinal tract and body fluids, and is related to the rate and extent of lactic

James E. Nocek

1997-01-01

290

Torque Performance and Permanent Magnet Arrangement for Interior Permanent Magnet Synchronous Motor  

Microsoft Academic Search

The use of the interior permanent magnet synchronous motor (IPMSM) has increased in the industrial field because of its excellent characteristics, such as high efficiency, wide range of speed operation and flexibility of the rotor structure. Therefore, the IPMSM, especially one using the rare earth permanent magnet, is being actively studied. In the IPMSM using the rare earth permanent magnet,

Naohisa Matsumoto; Masayuki Sanada; Shigeo Morimoto; Yoji Takeda

2006-01-01

291

Pulp tissue from primary teeth: new source of stem cells  

PubMed Central

SHED (stem cells from human exfoliated deciduous teeth) represent a population of postnatal stem cells capable of extensive proliferation and multipotential differentiation. Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED are highly proliferative cells derived from an accessible tissue source, and therefore hold potential for providing enough cells for clinical applications. In this review, we describe the current knowledge about dental pulp stem cells and discuss tissue engineering approaches that use SHED to replace irreversibly inflamed or necrotic pulps with a healthy and functionally competent tissue that is capable of forming new dentin. PMID:21625731

TELLES, Paloma Dias; MACHADO, Maria Aparecida de Andrade Moreira; SAKAI, Vivien Thiemy; NÖR, Jacques Eduardo

2011-01-01

292

Calcite orientations and composition ranges within teeth across Echinoidea.  

PubMed

Sea urchin's teeth from four families of order Echinoida and from orders Temnopleuroida, Arbacioida and Cidaroida were studied with synchrotron X-ray diffraction. The high and very high Mg calcite phases of the teeth, i.e. the first and second stage mineral constituents, respectively, have the same crystallographic orientations. The co-orientation of first and second stage mineral, which the authors attribute to epitaxy, extends across the phylogenic width of the extant regular sea urchins and demonstrates that this is a primitive character of this group. The range of compositions ?x for the two phases of Ca1-xMgxCO3 is about 0.20 or greater and is consistent with a common biomineralization process. PMID:25158180

Stock, Stuart R; Ignatiev, Konstantin; Lee, Peter L; Almer, Jonathan D

2014-08-01

293

A clinical and microbiological comparative study of deep carious lesion treatment in deciduous and young permanent molars.  

PubMed

The aim of this study was to compare one-visit indirect pulp treatment (IPT), two-visit IPT, and direct complete excavation (DCE) of deciduous and young permanent molars with deep carious lesions from clinical and microbiological points of view. One hundred thirty-five teeth (83 deciduous molars and 52 young permanent molars) were included in the study. The teeth were randomly selected and treated either with one-visit IPT, two-visit IPT, or DCE. For two-visit IPT, the final excavation was performed after a period of 3 months. The color, consistency, and humidity of the dentin at the cavity floor were recorded for clinical assessment, and dentin samples were obtained from all teeth. Dentin samples were microbiologically investigated for the total number of colony forming units, mutans streptococci, and lactobacilli. The results showed bacterial growth in 63.8% of the dentin samples in one-visit IPT, while in two-visit IPT, bacterial growth was observed in all of the samples (100%) after the first excavation. When the cavities were reopened before the final excavation, the number of samples with positive growth had decreased significantly (44.4%), and after the final excavation, the number of the samples with positive growth had decreased to 2.2%. In the DCE group, only 25.6% of the samples revealed bacterial growth. No statistical difference was found between deciduous and permanent molars in any of the treatment groups in terms of microbiologic results (p > 0.05). In conclusion, although none of the treatment methods completely eliminated the viable microorganisms during the initial excavations, a dramatic reduction in bacterial growth was detected during the treatment stages of two-visit IPT. PMID:18548292

Orhan, Ayse I; Oz, Firdevs T; Ozcelik, Berrin; Orhan, Kaan

2008-12-01

294

Modeling of permanent magnet motor drives  

Microsoft Academic Search

Research has indicated that the permanent magnet motor drives, which include the permanent magnet synchronous motor (PMSM) and the brushless DC motor (BDCM) could become serious competitors to the induction motor for servo applications. The PMSM has a sinusoidal back EMF and requires sinusoidal stator currents to produce constant torque while the BDCM has a trapezoidal back EMF and requires

PRAGASAN PILLAY; R. Krishnan

1988-01-01

295

Self-regulating permanent magnet linear motor  

SciTech Connect

A new type of self-regulating permanent magnet linear motor (PMLM) is proposed. This PMLM utilizes chiefly permanent magnets and a ferromagnetic yoke for producing a force to propel a flying vehicle. A detailed structure and the theory of the proposed PMLM are given. The PMLM is designed for vehicle propulsion in high speed ground transportation systems.

Tozoni, O.V.

1999-07-01

296

Permanent pacing for cardioinhibitory malignant vasovagal syndrome  

Microsoft Academic Search

OBJECTIVE--To evaluate the effect of permanent pacing in cardioinhibitory malignant vasovagal syndrome. PATIENTS AND METHODS--37 patients with permanent pacemakers for cardioinhibitory malignant vasovagal syndrome. All presented with syncope (median six episodes, median frequency two episodes a year) and after conventional investigation and invasive electrophysiological assessment they remained undiagnosed, and without a generally accepted indication for pacemaker implantation. In all vasovagal

M. E. Petersen; R. Chamberlain-Webber; A. P. Fitzpatrick; A. Ingram; T. Williams; R. Sutton

1994-01-01

297

Stem-cell-based Tissue Engineering of Murine Teeth  

Microsoft Academic Search

Teeth develop from reciprocal interactions between mesenchyme cells and epithelium, where the epithelium provides the instructive information for initiation. Based on these initial tissue interactions, we have replaced the mesenchyme cells with mesenchyme created by aggregation of cultured non-dental stem cells in mice. Recombinations between non-dental cell-derived mesenchyme and embryonic oral epithelium stimulate an odontogenic response in the stem cells.

A. Ohazama; S. A. C. Modino; I. Miletich; P. T. Sharpe

2004-01-01

298

Teeth Segmentation and Feature Extraction for Odontological Biometrics  

Microsoft Academic Search

During the past few years, advancements in high end computers and sensor techniques made it possible to develop a real-time odontological biometric identification and verification system apart from the existing offline forensic odontological systems. However, this requires highly automated teeth image segmentation and feature extraction algorithms. In this paper, we propose a novel non-forensic biometric technique, employing 3D optical sensors

Danish Mairaj; Stephen D. Wolthusen; Christoph Busch

2010-01-01

299

A partially mummified corpse with pink teeth and pink nails  

Microsoft Academic Search

A female corpse in a state of advanced decomposition and putrefaction with pink teeth and an equivalent discolouration of\\u000a several fingernails was found by a group of hunters in a forest. A combination of trimipramin intoxication, hypothermia and\\u000a pneumonia could be established as the cause of death. Autolysis or blood congestion can only favour the occurrence of a pink\\u000a discoloration.

C. Ortmann; A. DuChesne

1997-01-01

300

Technique for repair of multiple abutment teeth under preexisting crowns.  

PubMed

This technique describes a simple procedure for repairing multiple fractured or broken-down abutment teeth under existing crowns. The technique uses a Teflon tape polytetrafluoroethylene (PTFE) as a matrix and separating medium for fabrication of an autopolymerizing composite core material with digital pressure. This technique enables the dentist to solve an emergency clinical situation in a relatively short amount of time, pending further restoration with endodontic treatment and a cast post and core procedure. PMID:12589296

Chan, Daniel C N

2003-01-01

301

What is the Best Root Surface Treatment for Avulsed Teeth?  

PubMed Central

Dental avulsion is the most severe type of traumatic tooth injuries since it causes damage to several structures and results in avulsion of the tooth from its socket. Management protocols for avulsed teeth should include management of the pulp and periodontal ligament (PDL) cells in order to improve the long-term prognosis and survival of these teeth. The prognosis of the treatment as well as the survival of an avulsed tooth depends on intrinsic and extrinsic factors, such as the duration of the tooth’s extra-alveolar period, replantation time, the type of storage medium, PDL status and duration of splinting. Recent research has led to the development of storage media. However, there is not yet a single solution that fulfills all requirements to be considered as the ideal medium for temporary storage of avulsed teeth, and research on this field should carry on. On the other hand in case of delayed replantation, due to the great risk of tooth loss after avulsion, different root surface treatments have been proposed to prevent and delay root resorption before replantation. For this purpose, researchers have applied some different root surface treatment modalities in delayed replantation of avulsed teeth. Several protocols have been used to maintain PDL viability; some involve fluorides, steroids, sodium alendronate, enamel matrix derivatives (EMD) and basic fibroblast growth factor (bFGF, FGF-2). Among these applications, bFGF shows promising results in the regeneration of natural tooth structures and tissues. Better understanding of mechanism of bFGF may help to improve new technologies of regeneration of tooth structures. PMID:25317212

Tuna, Elif B; Yaman, Duygu; Yamamato, Seiko

2014-01-01

302

Radiographic Assessment and Chair Time of Rotary Instruments in the Pulpectomy of Primary Second Molar Teeth: A Randomized Controlled Clinical Trial  

PubMed Central

Background and aims. The superiority of rotary systems has been reported in several clinical studies on permanent teeth. This study consisted of radiographic assessment and chair time of rotary instruments in the pulpectomy of primary second molar teeth. Materials and methods. In this randomized controlled clinical study, 46 children, 3-6 years of age, were selected. The patients were divided randomly into two groups. In the first group (group A) pulpectomy was carried out with hand instruments and in the second group (group B) the Rotary FlexMaster System was used. T-test and chi-squared test were used to analyze data. Results. The mean instrumentation time in group A was significantly more than that in group B (P<0.001). Also there was a significant difference between both groups in relation to the distance between the apex of mesial root (P<0.001) and distal root (P=0.007) and the canal filling level. Conclusion. Superior radiographic findings and less chair time of pulpectomy with rotary instruments in second primary molar teeth were achieved. PMID:25093051

Makarem, Abbas; Ravandeh, Navid; Ebrahimi, Masoumeh

2014-01-01

303

Bleaching of nonvital teeth. A clinically relevant literature review.  

PubMed

Today, the bleaching of nonvital, discolored teeth is a low-risk routine treatment for improving esthetics. This review article focuses on the etiology of tooth discolorations, different treatment techniques, and risks of bleaching procedures. Some tooth discolorations in endodontically treated teeth are caused by dental treatments. The three most popular techniques for nonvital tooth bleaching are the walking bleach technique, inside/outside bleaching, and in-office bleaching. The walking bleach technique is a relatively reliable, fairly simple technique for dentists and patients. Inside/outside bleaching can be used additionally when internal and external bleaching must be combined. In-office bleaching seems to be a short-term solution, the effects of which can largely be attributed to dehydration of the teeth. There are still some open questions concerning the bleaching agents. Improved safety seems desirable with regard to adding thiourea as a scavenger of radicals or newer materials such as sodium percarbonate. The thermocatalytic technique, insufficient cervical sealing, and high concentrations of bleaching agents should be avoided, as this can increase the risk of cervical root resorptions. Patients should be informed about the low predictability of bleaching success and the risk of recurrent discoloration. The risk of cervical root resorption should be discussed with the patient. There is a strong correlation between root resorption and dental trauma. PMID:20514558

Zimmerli, Brigitte; Jeger, Franziska; Lussi, Adrian

2010-01-01

304

Modular turbine airfoil and platform assembly with independent root teeth  

DOEpatents

A turbine airfoil (22E-H) extends from a shank (23E-H). A platform (30E-H) brackets or surrounds a first portion of the shank (23E-H). Opposed teeth (33, 35) extend laterally from the platform (30E-H) to engage respective slots (50) in a disk. Opposed teeth (25, 27) extend laterally from a second portion of the shank (29) that extends below the platform (30E-H) to engage other slots (52) in the disk. Thus the platform (30E-H) and the shank (23E-H) independently support their own centrifugal loads via their respective teeth. The platform may be formed in two portions (32E-H, 34E-H), that are bonded to each other at matching end-walls (37) and/or via pins (36G) passing through the shank (23E-H). Coolant channels (41, 43) may pass through the shank beside the pins (36G).

Campbell, Christian X; Davies, Daniel O; Eng, Darryl

2013-07-30

305

A method for rapid demineralization of teeth and bones.  

PubMed

Tooth and bone specimen require extensive demineralization for careful analysis of cell morphology, as well as gene and protein expression levels. The LacZ gene, which encodes the ß-galactosidase enzyme, is often used as a reporter gene to study gene-structure function, tissue-specific expression by a promoter, cell lineage and fate. This reporter gene is particularly useful for analyzing the spatial and temporal gene expression pattern, by expressing the LacZ gene under the control of a promoter of interest. To analyze LacZ activity, and the expression of other genes and their protein products in teeth and bones, it is necessary to carry out a complete demineralization of the specimen before cutting sections. However, strong acids, such as formic acid used for tooth demineralization, destroy the activities of enzymes including those of ß-galactosidase. Therefore, most protocols currently use mild acids such as 0.1 M ethylene diamine tetra-acetic acid (EDTA) for demineralization of tooth and bone specimen, which require a longer period of treatment for complete demineralization. A method by which hard tissue specimens such as teeth and bones can be rapidly, but gently, decalcified is necessary to save time and effort. Here, we report a suitable method for rapid demineralization of mouse teeth in 0.1M EDTA at 42?C without any loss of ß-galactosidase activity. PMID:21339898

Cho, Andrew; Suzuki, Shigeki; Hatakeyama, Junko; Haruyama, Naoto; Kulkarni, Ashok B

2010-01-01

306

Gating of Permanent Molds for ALuminum Casting  

SciTech Connect

This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

David Schwam; John F. Wallace; Tom Engle; Qingming Chang

2004-03-30

307

Abstract Rodents have a toothless diastema region be-tween the incisor and molar teeth which may contain ru-  

E-print Network

Abstract Rodents have a toothless diastema region be- tween the incisor and molar teeth which may of diastema teeth represents a natural "experi- ment" which can be compared to the loss of teeth in gene knockout experiments. All teeth, regardless of shape or identity, pass through the same developmental

Jernvall, Jukka

308

Pull-Push Level Sets: A new term to encode prior knowledge for the segmentation of teeth images  

E-print Network

Pull-Push Level Sets: A new term to encode prior knowledge for the segmentation of teeth images for contour detection in multiple-object scenarios applied to the segmentation of teeth images. Teeth Information, Teeth 1. INTRODUCTION In accordance with the increasing relevance of medical imaging

309

An updated object oriented bovine QTL viewer and genome-wide bovine meta-analysis  

E-print Network

Waves of bovine genomic data have been produced as a result of the bovine genome sequencing projects. In addition to the massive amounts of genomic sequence, significant annotation including single nucleotide polymorphisms, sequence tagged sites...

Salih, Hanni

2009-05-15

310

Permanent Magnetic Bearing for Spacecraft Applications  

NASA Technical Reports Server (NTRS)

A permanent, totally passive magnetic bearing rig was designed, constructed, and tested. The suspension of the rotor was provided by two sets of radial permanent magnetic bearings operating in the repulsive mode. The axial support was provided by jewel bearings on both ends of the rotor. The rig was successfully operated to speeds of 5500 rpm using an air impeller. Radial and axial stiffnesses of the permanent magnetic bearings were experimentally measured and then compared to finite element results. The natural damping of the rotor was measured and a damping coefficient was calculated.

Morales, Winfredo; Fusaro, Robert; Kascak, Albert

2008-01-01

311

Human Antibodies to Bovine ?-Globulin  

Microsoft Academic Search

Antibodies to bovine ?-globulin (anti-BGG antibodies) were detectable by a radio-immunoassay in 70% of healthy blood donors but, generally, the titres were low. Significantly increased concentrations of anti-BGG antibodies were found in patients lacking IgA but not in patients with allergic disorders. The anti-BGG antibodies were shown to give rise to falsely high IgE values in the radio-immunosorbent test for

T. Foucard; H. Bennich; S. G. O. Johansson; U. Lundkvist

1975-01-01

312

Bovine ephemeral fever: a review.  

PubMed

Bovine ephemeral fever is a viral disease of cattle and buffaloes besides subclinical involvement of a variety of ruminant species. The subtropical and temperate regions of Africa, Asia and Australia have experienced the major epidemic of the bovine ephemeral fever but the occurrence in the tropics can not be overlooked. Although the substantial role played by the vectors viz., mosquitoes and culicoides in bovine ephemeral fever perpetuation and dissemination, other vector involvement if any should be extensively studied. The clinical severity of the disease is not apparent and the mortality is low. However, high morbidity, enormous economic losses in terms of significant reduction in production, disruption of national and international trade and finally a variety of complications resulting from the disease have drawn appreciable attention from the researchers around the world to resolve the unsolved questions in this area. In this review, detailed informations of all the aspects of the disease has been provided in a simple, lucid and easily understandable manner. PMID:10051179

Nandi, S; Negi, B S

1999-04-01

313

29 CFR 2582.8478-3 - Permanent bonding requirements.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Permanent bonding requirements. 2582.8478-3 Section...REGULATIONS FOR FIDUCIARY RESPONSIBILITY Permanent Bonding Rules § 2582.8478-3 Permanent bonding requirements. (a) General....

2010-07-01

314

29 CFR 2582.8478-3 - Permanent bonding requirements.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Permanent bonding requirements. 2582.8478-3 Section...REGULATIONS FOR FIDUCIARY RESPONSIBILITY Permanent Bonding Rules § 2582.8478-3 Permanent bonding requirements. (a) General....

2013-07-01

315

29 CFR 2582.8478-3 - Permanent bonding requirements.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Permanent bonding requirements. 2582.8478-3 Section...REGULATIONS FOR FIDUCIARY RESPONSIBILITY Permanent Bonding Rules § 2582.8478-3 Permanent bonding requirements. (a) General....

2011-07-01

316

29 CFR 2582.8478-3 - Permanent bonding requirements.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Permanent bonding requirements. 2582.8478-3 Section...REGULATIONS FOR FIDUCIARY RESPONSIBILITY Permanent Bonding Rules § 2582.8478-3 Permanent bonding requirements. (a) General....

2012-07-01

317

12 CFR 615.5206 - Permanent capital ratio computation.  

Code of Federal Regulations, 2010 CFR

... false Permanent capital ratio computation. 615.5206...5206 Permanent capital ratio computation. (a) The institution's permanent capital ratio is determined on the basis...accordance with generally accepted accounting principles except...

2010-01-01

318

Modeling and optimization of permanent magnetic motors  

E-print Network

This thesis develops analytic models for the prediction and optimization of radial-flux permanent magnet motor torque and efficiency. It also facilitates the design optimization of electromagnetically-powered rotorcraft ...

Pinkham, Andrew P

2008-01-01

319

Nonuniform radiation damage in permanent magnet quadrupoles  

NASA Astrophysics Data System (ADS)

We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL's pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

Danly, C. R.; Merrill, F. E.; Barlow, D.; Mariam, F. G.

2014-08-01

320

Approximating the Permanent with Fractional Belief Propagation  

E-print Network

We discuss schemes for exact and approximate computations of permanents, and compare them with each other. Specifically, we analyze the belief propagation (BP) approach and its fractional belief propagation (FBP) generalization ...

Yedidia, Adam B.

321

Prevalence of dental trauma in deciduous teeth of Brazilian children.  

PubMed

The aim of this study was to assess the prevalence of dental trauma as compared to the prevalence of dental caries in children aged 3-59 months. A cross-sectional study was carried out during the National Immunization Day for Polio in Recife, northeast Brazil. The sample comprised 3489 children under the age of 5. The clinical examination was performed by 123 previously trained dental students. The inter-examiner agreement for crown fracture was 90.32% and for tooth discoloration it was 83.87%. The prevalence of dental caries was assessed using the dmf-t index. The statistical methods included descriptive analysis and the chi-square test with a margin of error of 5%. A total of 56 142 teeth were examined and the prevalence of dental trauma was 14.9%. Dental fracture was the most prevalent injury observed in 516 teeth (0.9%), followed by discoloration in 191 (0.9%), intrusion in 12 (0.02%) and extrusion in five (0.008%). The most affected teeth were the upper central incisors. The prevalence of dental trauma increased significantly with age and family income (P < 0.0001). Dental trauma was most prevalent from 2 to 5 years of age. The prevalence of dental caries was 14.3%. This prevalence increased significantly with age (P < 0.0001) and with the reduction in family income (P < 0.0001). The results showed that the prevalence of dental caries and dental trauma was similar, and that both caused the same amount of damage to dental health for the target population. PMID:19290904

Ferreira, Jainara Maria Soares; Fernandes de Andrade, Ednara Mércia; Katz, Cíntia Regina Tornisiello; Rosenblatt, Aronita

2009-04-01

322

Tailored order: the mesocrystalline nature of sea urchin teeth.  

PubMed

We investigated the pattern of crystal co-orientation at different length scales, together with variations in chemical composition and nanomechanical properties in the teeth of the modern sea urchin Paracentrotus lividus with electron backscatter diffraction (EBSD), electron probe microanalysis, energy-dispersive X-ray spectroscopy and nanoindentation testing. Modern sea urchin teeth are Mg-dominated calcite composite materials. They are distinctly harder than inorganically precipitated calcite. Some parts exceed even the hardness of dolomite. The teeth show a structuring of their mechanical properties that can be correlated to variations in major element chemical composition, such that their hardness is positively correlated to their magnesium contents. Mg/Ca ratio in Paracentrotus lividus varies between 10 and 26mol.%. Nanohardness of the tooth scatters between 3.5 and >8GPa compared to values of 3.0±0.2, 7.3±0.1 and 9.2±0.9GPa measured on the (104) planes of inorganic calcite, dolomite and magnesite, respectively. High-resolution EBSD shows that major structural units and subunits of the tooth of Paracentrotus lividus are tilted to each other by ?3-5° and 1-2°, respectively. This indicates that the tooth is not a single crystal. With EBSD we can show that the tooth of the sea urchin Paracentrotus lividus is a hierarchically assembled biological mesocrystal with a mosaic texture. In comparison to the misorientation spread of 0.5° of calcite grown from solution, misorientation in the tooth varies between 2° and 4°. Thus, the self-sharpening feature of the tooth is enabled by a close interplay of its highly evolved micro- to nanostructure, structural unit size variations with a varying degree of crystal orientation, chemical structuring of the mineral component and a gradation of incorporated organic polymers. PMID:24937138

Goetz, Andreas J; Griesshaber, E; Abel, R; Fehr, Th; Ruthensteiner, B; Schmahl, W W

2014-09-01

323

Permanent magnet edge-field quadrupole  

DOEpatents

Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis. 10 figs.

Tatchyn, R.O.

1997-01-21

324

Permanent magnet edge-field quadrupole  

DOEpatents

Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.

Tatchyn, Roman O. (Mountain View, CA)

1997-01-01

325

Root canal obturation of primary teeth: disposable injection technique.  

PubMed

The aim of the study was to outline a simple, cost-effective technique for obturation of primary tooth root canals. A total of 75 primary teeth were treated in 52 subjects by the technique discussed, i.e. injecting plastic flowable material into the root canals after desired preparation, using disposable needle and syringe. All the patients were followed up for 3 years and 6 months, with no clinical or radiologic evidence of pathology or need for untimely extraction. In conclusion, the technique described is simple, economical, can be used with almost all filling materials used for the purpose, and is easy to master with minimal chances of failure. PMID:22565512

Bhandari, S K; Prajapati, U

2012-01-01

326

Immunomodulatory properties of stem cells from human exfoliated deciduous teeth  

Microsoft Academic Search

Introduction  Stem cells from human exfoliated deciduous teeth (SHED) have been identified as a population of postnatal stem cells capable\\u000a of differentiating into osteogenic and odontogenic cells, adipogenic cells, and neural cells. Herein we have characterized\\u000a mesenchymal stem cell properties of SHED in comparison to human bone marrow mesenchymal stem cells (BMMSCs).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  We used in vitro stem cell analysis approaches, including

Takayoshi Yamaza; Akiyama Kentaro; Chider Chen; Yi Liu; Yufang Shi; Stan Gronthos; Songlin Wang; Songtao Shi

2010-01-01

327

Bonding auto-polymerising acrylic resin to acrylic denture teeth.  

PubMed

This study investigated the effect of surface treatments on the shear bond strength of an auto-polymerising acrylic resin cured to acrylic denture teeth. The surface treatments included a combination of grit-blasting and/or wetting the surface with monomer. Samples were prepared and then stored in water prior to shear testing. The results indicated that the application of monomer to the surface prior to bonding did not influence the bond strength. Grit blasting was found to significantly increase the bond strength. PMID:19839190

Nagle, Susan; Ray, Noel J; Burke, Francis M; Gorman, Catherine M

2009-09-01

328

The bonded lingual retainer and multiple spacing of anterior teeth.  

PubMed

Retaining tooth positions after orthodontic space closure in cases with multiple spacing of anterior teeth are illustrated by selected cases with varying degrees of bimaxillary spacing initially (Figs. 1-6). In each case, bonded lingual retainers which allowed physiologic tooth movements were used with encouraging results. A meticulous technique for fabrication and bonding of flexible spiral wire retainers is mandatory for clinical success. Detailed recommendations are presented. If similar trials by others confirm the durability and effectiveness of acid-etched lingual retainers, it is expected that the technique can be recommended for routine clinical application. PMID:6963780

Zachrisson, B U

1982-01-01

329

Movement adds bite to the evolutionary morphology of mammalian teeth  

PubMed Central

Selection and constraints put limits on morphological evolution. Mammalian teeth are no exception, and the need for them to meet precisely exerts exacting constraints on a staggering array of developmental and functional factors that must be integrated to maintain their performance as they evolve. A study in BMC Evolutionary Biology demonstrates that mandibular movement is an important component of this integration, and one that should not be neglected in the quantitiative study of the evolution of tooth morphology. See research article http://www.biomedcentral.com/1471-2148/12/146/ PMID:22898247

2012-01-01

330

Anesthetic efficacy of infiltrations in mandibular anterior teeth.  

PubMed Central

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 lateral incisor apex cannot be recommended clinically to provide profound pulpal anesthesia. PMID:11515948

Yonchak, T.; Reader, A.; Beck, M.; Clark, K.; Meyers, W. J.

2001-01-01

331

Identification of supernumerary teeth in 2D and 3D: review of literature and a proposal.  

PubMed

Supernumerary teeth occur in both syndromic and nonsyndromic patients, and dental professionals are likely to encounter such teeth in their professional careers. There are three main numbering systems used to identify teeth today: the Universal/ National, the Palmer/Zsigmondy notation, and the Federation Dentaire Internationale (FDI) numbering systems. However, a review of the literature suggests that none of these three consistently addresses the identification of supernumerary teeth. Being able to communicate the location of supernumerary teeth is important for dental professionals, especially in interdisciplinary situations. This article proposes a guideline to locate and identify supernumerary teeth in two and three dimensions, which may reduce treatment errors and improve communication among health care providers and third-party administrators. PMID:23314464

Toureno, Leo; Park, Jae Hyun; Cederberg, Robert A; Hwang, Eui Hwan; Shin, Je-Won

2013-01-01

332

Replacement of Missing Anterior Teeth in a Patient with Temporomandibular Disorder  

PubMed Central

The loss of anterior teeth leads to extreme psychological trauma, along with functional and esthetic debilitations. Healthy anterior teeth play an important role of protecting the posterior teeth during excursive mandibular movement. Loss of anterior teeth induces posterior interference with extended disocclusion time. Posterior disocclusion is critical to remove the harmful force on the teeth temporomandibular joint and eliminate muscle hypertonicity. Occlusal interference is considered as contributing factor to temporomandibular disorder (TMD) symptoms. Prosthesis design should eliminate deleterious tooth contacts. Establishing optimum anterior guidance is a key to establishing harmonious functional occlusion in addition to the correction of the esthetic and phonetic disabilities. This case report explains the steps involved in the rehabilitation of the TMD patient with loss of maxillary anterior teeth. PMID:24715993

Haralur, Satheesh B.; Saeed Al-Shahrani, Omar

2014-01-01

333

Replacement of maxillary permanent central incisors lost due to trauma in the mixed-dentition.  

PubMed

Traumatic injuries to anterior teeth in children range from minor chipping to total tooth loss and occur more often in boys than in girls. The treatment of permanent tooth loss in younger patients is complicated by the difficulty of doing restorative procedures which may be influenced by pulpal size, clinical crown height, and a dental profile which is constantly changing. This case report presented a situation involving a 9-year-old boy who had experienced traumatic loss of the maxillary central incisors. Innovative materials coupled with sound principles of removable partial denture design were utilized to fabricate a cast metal removable denture prosthesis to satisfy the esthetic, functional and psychological dental needs of the patient and his parents. PMID:25265859

Rubel, Barry; Hill, Edward E

2014-08-01

334

Reconstructing the Habitat Mosaic of Australopithecus robustus: Evidence from Quantitative Morphological Analysis of Bovid Teeth  

E-print Network

..................................................................... 49 3.2.4 Age and attrition test ..................................................... 51 3.3 Results of the analyses by tribe .................................................... 54 3.3.1 Alcelaphini... results for the M3 teeth in the tribe Alcelaphini ................................. 55 3.4 DFA results for the M2 teeth in the tribe Alcelaphini ................................. 56 3.5 DFA results for the M1 teeth in the tribe Alcelaphini...

Brophy, Juliet

2012-02-14

335

[Effect of selective polishing of teeth on local circulation in prosthetic treatment by implantation].  

PubMed

An effect of occlusion disorders on a regional circulation was studied in periodontal tissues of abutment teeth, antagonist teeth, periimplant zone at different stages of preparation for a prosthesis by normalization of occlusion ratios by means of selective polishing of teeth. The terms and the periodicity of selective polishing promoting redistribution of the masticating pressure were determined. The connection of these factors was examined with periodontal vessel tonicity and periimplant zone on the basis of the rheoparodontographic findings. PMID:12532892

Zolotareva, Iu B; Guseva, I E; Diudin, A N

2002-01-01

336

Fatty Acids of Healthy and Periodontally Diseased Root Substance in Human Teeth  

Microsoft Academic Search

In this comparative study, samples of root substance from healthy and periodontally diseased human teeth were analyzed for fatty acids by means of a gas-chromatographic technique. The sample preparation procedure allowed specimens from individual teeth to be analyzed. The content of the fatty acids C16:0, C16:1, C18:0, and C 18:1 in the superficial layer ofthe periodontally diseased teeth was significantly

H. Lygre; E. Solheim; N. R. Gjerdet; N. Skaug

1992-01-01

337

Increased effect of harsh climate in red deer with a poor set of teeth  

Microsoft Academic Search

Teeth are vital for mammal performance and especially in ungulates relying on mechanical decomposition of plant material for\\u000a effective microbial digestion and energy uptake. The main focus of the role of teeth in ungulate life histories has been on\\u000a tooth wear, while no one has addressed to what extent deviation from the natural set of teeth (maldentition) causes variation\\u000a in

Leif Egil Loe; Christophe Bonenfant; Rolf Langvatn; Atle Mysterud; Vebjørn Veiberg; Nils Chr. Stenseth

2006-01-01

338

Pharyngeal teeth and masticatory process of the basioccipital bone in Japanese bitterlings (Cyprinidae)  

Microsoft Academic Search

The pharyngeal teeth and the masticatory process of the basioccipital bone were compared in fifteen species and subspecies\\u000a of Japanese bitterlings.Acheilognathus lanceolata, A. limbata and two subspecies ofRhodeus ocellatus, which are characterized by the absence of serrations on the side of the pharyngeal teeth, have reduced occlusal grooves\\u000a on the pharyngeal teeth. In the larvae of these species, the occlusal

Nobuhiro Suzuki; Takashi Hibiya

1985-01-01

339

EDITORIAL: Permanent revolution - or evolution?  

NASA Astrophysics Data System (ADS)

Honorary Editor It was that temporary Bolshevik Leon Trotsky who developed the principle of `permanent revolution', a principle that perhaps characterizes the recent history of education in (south) Britain more than does, say, principles traditionally associated with the Conservative or Labour parties. As this editorial is being written, changes are being made to primary school education, and the long-awaited details of the post-Dearing reorganizing of post-16 education are yet to hit the overful bookshelves and filing cabinets of school heads and examination board officials. But something unique has happened recently which might have surprised even Trotsky. The Secretary of State for Education has set up targets for primary school pupils' attainment and threatened (or promised) to resign if they are not met within the lifetime of our newly elected parliament. Of course, if Mr Blunkett is still in a position to resign at that stage he will have been the longest serving Secretary of State since time immemorial. But we should not carp: this is truly a revolutionary idea. Not the promise to resign - although this idea is not so fashionable now as it once was. The revolutionary idea is that a major change to an educational process is actually being made that carries with it a predicted and testable outcome. By contrast, when school physics was refreshed a generation ago by the introduction of Nuffield courses at both pre- and post-16 stages, no `targets' were set. I and many other physics teachers certainly preferred teaching these to teaching their predecessor syllabuses, and might even dare to assert that the pupils liked them too. But we still don't really know whether or not they learned more - or even better - physics. Very little happened as far as the outside world was concerned: the usual fraction of students gave up physics at the usual ages, and those who were examined didn't really get a better reward for their more up-to-date and more enjoyably learned physics. The same fraction of candidates passed at O- and A-level, with much the same distribution of grades. But then at least, amongst other things, we may claim to have produced happier and more knowledgeable failures. Mr Blunkett's revolutionary idea should be extended so that any major educational change must be capable of evaluation. The customers/victims should actually be shown to have benefited - more of them should do better! It is a regrettable fact of history that most revolutions have resulted in tears before bedtime, however bright the following dawn. One problem with revolutions, as Maxim Gorky often pointed out, is that `inside every revolutionary there is a gendarme'. It is one thing to specify a target, another to direct in detail how every child and teacher in the land should achieve it. The latter is very difficult to manage, and when patience inevitably runs out there is likely to be a tendency towards gendarmerie. The control structure begins to dominate the educational one, and the means of control become more important than the ends. Rigidity replaces creativity, fossilization replaces evolution, and the energies and skills of practitioners may be devoted more to conforming passively with or ingeniously evading the constraints of a rule-bound system. There were signs that this effect exists and has been growing, but happily these signs have been detected by the `gendarmerie' and recognized as being deleterious. Government agencies are now consulting, seriously, with practitioners and such organizations as the IoP. It may well be that when the magic number 2000 arrives there will be a well-designed, self-organizing and self-monitoring National Curriculum that will engage the hearts as well as develop the minds of the young.

Dobson, Ken

1998-03-01

340

Laser ultrasound characterization of normal and decayed teeth by measuring elastic properties of surface layers  

NASA Astrophysics Data System (ADS)

We firstly investigate the mechanic and acoustic properties of human teeth by using the laser generation of surface acoustic wave (SAW) technique. The materials investigated included normal and decayed teeth, which have the same grain size and different thickness, are used as the samples. The tissue responds to the laser-induced stress by thermoelastic expansion. We can obtain the shape of acoustic pulse and the phase velocity was determined for the teeth system and extract information on the teeth thickness, density, and transverse sound velocity that could be used as diagnostic parameters.

El-Sharkawy, Yasser H.; ElSherif, Ashraf F.

2011-03-01

341

Scanning electron microscopic analysis of incinerated teeth: An aid to forensic identification  

PubMed Central

Background: Forensic dental identification of victims involved in fire accidents is often a complex and challenging endeavor. Knowledge of the charred human dentition and residues of restorative material can help in the recognition of bodies burned beyond recognition. Aim: To observe the effects of predetermined temperatures on healthy unrestored teeth and different restorative materials in restored teeth, by scanning electron microscope, for the purpose of identification. Materials and Methods: The study was conducted on 135 extracted teeth, which were divided into four groups. Group 1-healthy unrestored teeth, group 2-teeth restored with all ceramic crowns, group 3-teeth restored with class I composite resin and group 4-teeth restored with class I glass ionomer cement (GIC). Results: The scanning electron microscope is useful in the analysis of burned teeth, as it gives fine structural details, requires only a small sample and does not destroy the already fragile specimen. Conclusion: Scanning electron microscope can be a useful tool for the characterization and study of severely burnt teeth for victim identification. PMID:24959034

Pol, Chetan A; Gosavi, Suchitra R

2014-01-01

342

[Biomechanical basis splinting of loose teeth while preserving their mobility at physiological].  

PubMed

The aim of this study was biomechanical rationale for splinting mobile teeth with periodontitis according to the height and slope of teeth crowns, their degree of mobility, and type of occlusion. The research studied the effect of axial vertical and horizontal loads on the functioning of the proposed method of splinting. Set clear indications and contraindications for the use of the method of splinting. Biomechanically proven unreasonableness includes teeth with III degree of mobility in the splinted construction. Clinical variant of splinting is only possible at the height of the anatomical crowns of the teeth of at least 7 mm, otherwise the preferred laboratory methods for the manufacture of tires. PMID:24099811

Belikova, N; Petrushanko, T

2013-09-01

343

Stem Cells in Dental Pulp of Deciduous Teeth  

PubMed Central

Dental pulp from deciduous (baby) teeth, which are discarded after exfoliation, represents an advantageous source of young stem cells. Herein, we discuss the methods of deciduous teeth stem cell (DTSC) isolation and cultivation. We show that based on these methods, at least three different stem cell populations can be identified: a population similar to bone marrow–derived mesenchymal stem cells, an epithelial stem–like cells, and/or a mixed population composed of both cell types. We analyzed the embryonic origin and stem cell niche of DTSCs with respect to the advantages they can provide for their future use in cell therapies and regenerative medicine. In vitro and in vivo differentiation of the DTSC populations, their developmental potential, immunological compatibility, tissue engineering, and transplantation use in studies in animal models are also the focus of the current report. We briefly describe the derivation of induced pluripotent stem (iPS) cells from DTSCs, which can be obtained more easily and efficiently in comparison with human fibroblasts. These iPS cells represent an interesting model for the investigation of pediatric diseases and disorders. The importance of DTSC banking is also discussed. PMID:22032258

Caplan, Arnold I.

2012-01-01

344

Revealing the structural and mechanical characteristics of ovine teeth.  

PubMed

The survival and function of dentition over the lifetime of an animal depends upon the ability of the teeth to resist wear and chemical erosion, and to withstand occlusal loading conditions without suffering debilitating fracture. Understanding how geometrical factors (radius, height, enamel thickness) and mechanical properties of the dental tissues (Young's modulus E, hardness H and toughness KIC of enamel and dentin) combine to ensure the survival of an animal's teeth can provide great insight into the evolutionary history of the animal and its dietary adaptation. While the geometrical factors are beginning to be understood, the range of animals for which measurements of dental tissue properties are available is very narrow, being restricted almost entirely to humans and other primates. The absence of comparative data across a broader range of species makes it impossible to draw conclusions with any certainty. The present study expands knowledge of mammalian dental tissue properties by reporting the Young's modulus and hardness of ovine (sheep) enamel and dentin measured using nano-indentation. We found that sheep molar enamel Young's modulus and hardness are both lower than those of human enamel, by approximately 30%, and 9% respectively, while the properties of dentin are similar. The combination of E and H makes the ovine enamel approximately 30% more resistant to wear than human enamel, which is an imperative in ruminant dentition. The results of this study are interpreted in terms of the ovine feeding ecology, and the structure of the ovine molar and its occlusal surface. PMID:24316873

O'Brien, Simona; Keown, Amanda J; Constantino, Paul; Xie, Zonghan; Bush, Mark B

2014-02-01

345

Performance of four dentine excavation methods in deciduous teeth.  

PubMed

This in vitro study aimed to assess the speed and caries removal effectiveness of four different new and conventional dentine excavation methods. Eighty deciduous molars were assigned to four groups. Teeth were sectioned longitudinally through the lesion centre. Images of one half per tooth were captured by light microscope and confocal laser scanning microscopy (CLSM) to assess the caries extension. The halves were then reassembled and caries removed using round carbide bur (group 1), Er:YAG laser (group 2), hand excavator (group 3) and a polymer bur (group 4). The time needed for the whole excavation in each tooth was registered. After excavation, the halves were photographed by light microscope. Caries extension obtained from CLSM images were superimposed on the post-excavation images, allowing comparison between caries extension and removal. The regions where caries and preparation limits coincided, as well as the areas of over- and underpreparation, were measured. Steel bur was the fastest method, followed by the polymer bur, hand excavator and laser. Steel bur exhibited also the largest overpreparation area, followed by laser, hand excavator and polymer bur. The largest underpreparation area was found using polymer bur, followed by laser, hand excavator and steel bur. Hand excavator presented the longest coincidence line, followed by polymer and steel burs and laser. Overall, hand excavator seemed to be the most suitable method for carious dentine excavation in deciduous teeth, combining good excavation time with effective caries removal. PMID:16508268

Celiberti, P; Francescut, P; Lussi, A

2006-01-01

346

Wear Resistance of Coating Films on Hob Teeth  

NASA Astrophysics Data System (ADS)

The wear resistance of coating films on hob teeth is investigated through the simulated hobbing tests with a flytool. The coating films on hob teeth are titanium family ceramics such as TiN, TiCN, TiSiN and TiAlN and aluminum chromium family ceramics such as AlCrN and AlCrSiN. The wear of coated tools is shown about film thickness, film materials, ingredient ratio in a film component and the oxidization of coating films. The oxidization is clarified from a result of the influence on the crater wear progress through wear cutting tests in atmosphere of nitrogen gas or oxygen gas. The oxidization of TiAlN coating films produces oxide products on the tool rake face, and this oxidation relates to the amount of crater wear. The increase of aluminum concentration in the TiAlN film improves the crater wear resistance in air atmosphere, while it has a reverse effect in nitrogen gases. The AlCrSiN film has effective wear resistance against the abrasive wear and/or oxidization wear. The oxidation film formed on the AlCrSiN film is very firm and this suppresses the oxidation wear on the rake face and works against the abrasive wear advantageously.

Umezaki, Yoji; Funaki, Yoshiyuki; Kurokawa, Syuhei; Ohnishi, Osamu; Doi, Toshiro

347

Communication BoLA et leucose bovine  

E-print Network

Communication BoLA et leucose bovine H. Leveziel INRA-CRJ, laboratoire de génétique biochimique scientifique - structure - fonction BOLA and bovine leucosis major histocompatibility complex - scientific rôle possible du complexe majeur d'histocompatibilité (complexe BoLA). Le protocole mis en place en

Paris-Sud XI, Université de

348

Characterization of gender-specific bovine serum  

Microsoft Academic Search

Animal cell cultures generally require a nutrient-rich medium supplemented with animal serum. Adult bovine serum contains a variety of nutrients including inorganic minerals, vitamins, salts, proteins and lipids as well as growth factors that promote animal cell growth. To evaluate the potential use of gender-specific bovine serum (GSBS) for cell culture, the biochemical properties of male serum (MS), female serum

Jihoe Kim; Minsoo Kim; Sang-Soep Nahm; Dong-Mok Lee; Smritee Pokharel; Inho Choi

2011-01-01

349

Apoptosis induced by bovine ephemeral fever virus  

Microsoft Academic Search

The potential significance of bovine ephemeral fever virus (BEFV)-induced apoptosis and involved viral molecules was fully unknown. In the present study, evidence is provided demonstrating that bovine ephemeral fever virus induces apoptosis in several cell lines. Five types of assays for apoptosis were used in examining BEFV-infected cells. (1) Assay for DNA fragmentation, (2) nuclear staining with acridine orange, (3)

Chia J. Chang; Wen L. Shih; Feng L. Yu; Ming H. Liao; Hung J. Liu

2004-01-01

350

Bovine Growth Hormone: Human Food Safety Evaluation  

Microsoft Academic Search

Scientists in the Food and Drug Administration (FDA), after reviewing the scientific literature and evaluating studies conducted by pharmaceutical companies, have concluded that the use of recombinant bovine growth hormone (rbGH) in dairy cattle presents no increased health risk to consumers. Bovine GH is not biologically active in humans, and oral toxicity studies have demonstrated that rbGH is not orally

Judith C. Juskevich; C. Greg Guyer

1990-01-01

351

HORIZONTAL TRANSMISSION STUDIES ON ENZOOTIC BOVINE LEUKOSIS  

E-print Network

and see- ded each in a roller flask with 30 ml Eagle's suspension medium containing 20 % fetal calf serum, the reference bovine serum used throug- hout was derived from an experimental bull which was usedHORIZONTAL TRANSMISSION STUDIES ON ENZOOTIC BOVINE LEUKOSIS O.C. STRAUB Federal Research Institute

Paris-Sud XI, Université de

352

PROSTAGLANDINS AND SUPEROVULATION IN THE BOVINE  

E-print Network

PROSTAGLANDINS AND SUPEROVULATION IN THE BOVINE M. PHILLIPPO L. E. A. ROWSON Rowett Research in the bovine has been induced by the use of pregnant mares serum gonadotrophin (PMSG) given on the 15th or I6th disodium ethylene diamine tetra-acetate or sodium heparin. They were stored in ice, the plasma separated

Paris-Sud XI, Université de

353

Cylindrical Hall thrusters with permanent magnets  

NASA Astrophysics Data System (ADS)

The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction in both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT.

Raitses, Yevgeny; Merino, Enrique; Fisch, Nathaniel J.

2010-11-01

354

Factors Controlling Hydrologic Permanence of Headwater Streams  

NASA Astrophysics Data System (ADS)

Headwater streams compose the majority of stream miles within most drainages. Interest in monitoring headwater streams is increasing because these streams are vital linkages between upland land use and downstream water bodies. However, traditional stream assessment tools are often unsuitable because many headwater streams are prone to natural drying. Our objective was to identify physical characteristics of headwater reaches that are indicative of hydrologic permanence, a critical first step in applying a stream assessment. We surveyed 61 reaches along 17 headwater streams (< 2.6 km2) across 4 forests in Indiana, Kentucky and Ohio. Reaches varied in hydrologic permanence over the 2-year study. Exploratory data analysis (CART and discriminant analysis) was used to identify physical parameters for classifying reaches by hydrologic permanence. Drainage area was a consistent parameter discriminating permanence categories and consistently separated ephemeral from perennial and intermittent reaches. Secondary parameters that distinguished intermittent from ephemeral and perennial reaches included bankfull width, maximum pool depth, and channel entrenchment. These factors represent basin and reach scales, suggesting that hydrologic permanence in stream networks should be investigated in a hierarchical context. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

Fritz, K. M.; Johnson, B. R.; Walters, D. M.

2005-05-01

355

Cylindrical Hall Thrusters with Permanent Magnets  

SciTech Connect

The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction of both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50W-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT. __________________________________________________

Yevgeny Raitses, Enrique Merino and Nathaniel J. Fisch

2010-10-18

356

PERMANENT GENETIC RESOURCES NOTE Permanent Genetic Resources added to Molecular Ecology  

E-print Network

Database 1 April 2010 ­ 31 May 2010 MOLECULAR ECOLOGY RESOURCES PRIMER DEVELOPMENT CONSORTIUM, K. ANDREE,1PERMANENT GENETIC RESOURCES NOTE Permanent Genetic Resources added to Molecular Ecology Resources JAN AXTNER,2 M. J. BAGLEY,3 E. J. BARLOW,4, 5 T. J. C. BEEBEE,6 JEFFREY L. BENNETZEN,7 ELDREDGE

Loughry, Jim

357

PERMANENT GENETIC RESOURCES NOTE Permanent Genetic Resources added to Molecular Ecology  

E-print Network

PERMANENT GENETIC RESOURCES NOTE Permanent Genetic Resources added to Molecular Ecology Resources Database 1 October 2012­30 November 2012 MOLECULAR ECOLOGY RESOURCES PRIMER DEVELOPMENT CONSORTIUM,1 SERAP,7 JEFFREY L. BENNETZEN,8 RICARDO A. BRASSALOTI,9 TREENA I. BURGESS,10 ADAGISA CACCONE,11 SHU

Medrano, Mónica

358

Multispectral near-IR reflectance and transillumination imaging of teeth  

PubMed Central

NIR imaging methods do not require ionizing radiation and have great potential for detecting caries lesions (tooth decay) on high-risk proximal and occlusal tooth surfaces and at the earliest stages of development. Previous in vitro and in vivo studies at 1300-nm demonstrated that high contrast reflectance and transillumination images could be acquired of caries lesions on tooth proximal and occlusal surfaces where most new decay is found. Water absorption varies markedly between 1200 and 1600-nm and the scattering properties of enamel and the underlying dentin have not been characterized in this region. Hyperspectral reflectance studies show lower reflectivity from sound enamel and dentin at NIR wavelengths with higher water absorption. The purpose of this imaging study was to determine which NIR wavelengths between 1200 and 1600-nm provide the highest contrast of demineralization or caries lesions for each of the different modes of NIR imaging, including transillumination of proximal and occlusal surfaces along with cross polarization reflectance measurements. A tungsten halogen lamp with several spectral filters and a Ge-enhanced CMOS focal plane array (FPA) sensitive from 400 to 1600-nm were used to acquire the images of caries lesions on extracted teeth. Artificial interproximal lesions were created on twelve tooth sections of 5 & 6-mm thickness that were used for transillumination imaging. Fifty-four extracted teeth with suspected occlusal lesions were also examined in both occlusal transillumination and reflectance imaging modes. Cavity preparations were also cut into whole teeth and filled with composite and used to compare the contrast between composite and enamel at NIR wavelengths. NIR wavelengths longer than 1400-nm are likely to have better performance for the transillumination of occlusal caries lesions while 1300-nm appears best for the transillumination of proximal surfaces. Loss of mobile water in enamel markedly reduced the transparency of the enamel at all NIR wavelengths. Significantly higher contrast was attained for reflectance measurements at wavelengths that have higher water absorption, namely 1460-nm. Wavelengths with higher water absorption also provided higher contrast of composite restorations. PMID:22025986

Chung, Soojeong; Fried, Daniel; Staninec, Michal; Darling, Cynthia L.

2011-01-01

359

Original article Effects of bovine colostrum acid protein on bone  

E-print Network

Original article Effects of bovine colostrum acid protein on bone loss and hemobiochemistry indexes that bovine milk and its basic proteins, and bovine colostrums (BC) and their extracts have positive effects hazard on blood lipids of rats under present experimental condition. bovine colostrum / acid protein

Boyer, Edmond

360

NON-SPECIFIC ANTIVIRAL ACTIVITY OF BOVINE LEUKOCYTES AGAINST  

E-print Network

Minimum Essen- tial Eagle's Medium with 10 % calf serum. A cell suspension of count 2x 105 was preparedNON-SPECIFIC ANTIVIRAL ACTIVITY OF BOVINE LEUKOCYTES AGAINST INFECTIOUS BOVINE RHINOTRACHEITIS ANTIVIRALE DES LEUCOCYTES DE BOVINS. - Les leucocytes du sang de bovin empêchent la multiplication du virus

Paris-Sud XI, Université de

361

TSI (teething ring sound instrument): a design of the sound instrument for the baby  

Microsoft Academic Search

In this paper, we will describe the TSI (Teething ring Sound Instrument), a new sound instrument given to babies, which consists of a teething ring, a knob, an I-CubeX Digitizer [1] and a computer which processes MIDI messages. The TSI is designed to bring music experience to baby with the movement of the babies reflex sucking motion. We provided the

Naoko Kubo; Kazuhiro Jo; Ken Matsunaga

2001-01-01

362

Bacterial profile in primary teeth with necrotic pulp and periapical lesions  

Microsoft Academic Search

The objective of this study was to evaluate the bacterial profile in root canals of human primary teeth with necrotic pulp and periapical lesions using bacterial culture. A total of 20 primary teeth with necrotic pulp and radiographically visible radiolucent areas in the region of the bone furcation and\\/or the periapical region were selected. After crown access, 4 sterile absorbent

Léa Assed Bezerra da Silva; Paulo Nelson-Filho; Gisele Faria; Maria Cristina Monteiro de Souza-Gugelmin; Izabel Yoko Ito

2006-01-01

363

FOLLOWING BIOMINERAL DEPOSITION FRONTS IN MARINE CHITON TEETH BY RAMAN SPECTROSCOPY  

Microsoft Academic Search

In situ Raman microscopy has been used to follow biomineral deposition wavefronts in single chiton teeth. These results demonstrate that the elements detected by energy dispersive spectroscopy (EDS) may not always represent the presence of a deposited mineral. The structure and composition of the major lateral teeth of chitons (Mollusca: Polyplacophora) is of considerable interest due to their use of

A. P. Lee; W. Van Bronswik; J. Webb; D. J. Macey; L. Brooker

364

Number of teeth and myocardial infarction and stroke among elderly never smokers  

Microsoft Academic Search

BACKGROUND: In most previous studies the association between number of teeth and cardiovascular diseases has been found to be stronger among younger age groups than in older age groups, which indicates that age may modify the association between number of teeth and cardiovascular diseases. We investigated the association between tooth loss and atherosclerotic vascular diseases such as myocardial infarction and

Anna-Maija H Syrjälä; Pekka Ylöstalo; Sirpa Hartikainen; Raimo Sulkava; Matti L Knuuttila

2009-01-01

365

LETTER doi:10.1038/nature12169 Barium distributions in teeth reveal early-life dietary  

E-print Network

for reconstruct- ing diet as they contain precise temporal and chemical records of early life4 . Teeth begin at weaning as Ba (and Ca) content and bioavail- ability is markedly different across plant and animal food sources11,12 . To test this hypothesis, we investigated Ba/Ca patterns in teeth from human children

Gunawardena, Jeremy

366

Gene expression analysis in cells of the dentine–pulp complex in healthy and carious teeth  

Microsoft Academic Search

Knowledge of the molecular events that occur in carious disease has so far been constrained due to difficulties in obtaining sufficient quantities of the dental tissues and cells involved. Our histological findings indicate that a pulp–odontoblast cellular complex can be obtained from carious and healthy human teeth when exposed to low-temperatures prior to pulpal extirpation and from rodent teeth processed

Julia L McLachlan; Anthony J Smith; Alastair J Sloan; Paul R Cooper

2003-01-01

367

Crack arrest within teeth at the dentinoenamel junction caused by elastic modulus mismatch  

Microsoft Academic Search

Enamel and dentin compose the crowns of human teeth. They are joined at the dentinoenamel junction (DEJ) which is a very strong and well-bonded interface unlikely to fail within healthy teeth despite the formation of multiple cracks within enamel during a lifetime of exposure to masticatory forces. These cracks commonly are arrested when reaching the DEJ. The phenomenon of crack

Sabine Bechtle; Theo Fett; Gabriele Rizzi; Stefan Habelitz; Arndt Klocke; Gerold A. Schneider

2010-01-01

368

Performance of shark teeth during puncture and draw: implications for the mechanics of cutting  

E-print Network

into the evolution of shark feeding because teeth are often the only structures available in the fossil record are often the only structures available in the fossil record (Carroll, 1988).*Corresponding author. E teeth, tearing-type, cutting-type, and cutting­clutching type, as well as three fossil morpholo- gies

Motta, Philip J.

369

Analysis of stresses in complete upper dentures with flat teeth at differing inclinations  

Microsoft Academic Search

This study measures the effect of the inclination of the occlusal surfaces of flat teeth, on the magnitude of exerted stresses in a model of the complete upper denture (CUD), in order to estimate which inclination could be more beneficial for the stressed denture.Three groups of dentures were produced, with three different inclinations of their posterior flat teeth on the

Anthony E. Prombonas; Dimitris S. Vlissidis

2009-01-01

370

The laterally varying ultrasonic velocity in the dentin of human teeth  

Microsoft Academic Search

There is no quantitative description available that numerically relates any acoustic parameter pattern or the local elastic behaviour to any standardized geometrical positions within human teeth. However, the speed of ultrasound at 20MHz varies in different parts of teeth. Great differences occur between the values attributed to longitudinal waves that propagate in the three mineralized human hard tissues at identical

Christoph John

2006-01-01

371

Birdlike characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia)  

Microsoft Academic Search

The discovery of a new dentary of “Stenonychosaurus inequalis” with six germ teeth prompted a critical examination of all jaws and teeth attributed to Troodon, Stenonychosaurus, and Pectinodon. It is concluded that Troodon is the senior synonym of these genera, and that the name Troodontidae has priority over Saurornithoididae. Troodontid dentaries are unique amongst the Theropoda in that they lack

Philip J. Currie

1987-01-01

372

A reassessment of the Neanderthal teeth from Taddeo cave (southern Italy)  

Microsoft Academic Search

The Middle Paleolithic fossil human teeth from Taddeo cave in southwestern Italy were discovered in 1967, but to date only scanty and partially incorrect information has been published about them. The teeth were recovered in a reddish sandy layer from the cave’s floor, which is attributed either to an early phase of Würm I (OIS 5c or 5d) or a

Stefano Benazzi; Bence Viola; Ottmar Kullmer; Luca Fiorenza; Katerina Harvati; Tobias Paul; Giorgio Gruppioni; Gerhard W. Weber; Francesco Mallegni

2011-01-01

373

Magnetic guns with cylindrical permanent magnets  

NASA Astrophysics Data System (ADS)

The motion of a cylindrical permanent magnet (projectile) inside a tubular permanent magnet, with both magnets magnetized axially, illustrates nicely the physical principles behind the operation of magnetic guns. The force acting upon the projectile is expressed semi-analytically as derivative of the magnetostatic interaction energy. For comparison, the forces involved are also calculated numerically using finite elements methods. Based on the conservation of the magnetostatic and kinetic energies, the exit and asymptotic velocities are determined. The derived formulas can be used to optimize the generated forces and motion of the inner cylindrical magnet.

Vokoun, David; Beleggia, Marco; Heller, Lud?k

2012-05-01

374

The phylogeny of permanent prostate brachytherapy  

PubMed Central

Permanent prostate brachytherapy has been practiced for more than a century. This review examines the influence of earlier procedures on the modern transperineal ultrasound-directed technique. A literature review was conducted to examine the origin of current clinical practice. The dimensions of the modern brachytherapy seed, the prescription dose, and implant/teletherapy sequencing are vestigial features, which may be suboptimal in the current era of low-energy photon-emitting radionuclides and computerized dose calculations. Although the modern transperineal permanent prostate implant procedure has proven to be safe and effective, it should undergo continuous re-evaluation and evolution to ensure that its potential is maximized. PMID:23878553

Aronowitz, Jesse N.

2013-01-01

375

Permanently installed guided wave pipeline monitoring  

NASA Astrophysics Data System (ADS)

Permanently installed guided wave sensors are an attractive option for pipeline inspection as they offer significant inspection cost reductions and enhanced damage monitoring. This paper presents a statistical method with which data collected from industrial sensor installations over time can be analyzed to detect damage with set probabilities of detection and false-calling, and to model how damage sensitivity will evolve over time as a result of environmental effects. This information can be then used to actively adjust the data collection interval of permanently installed sensors in order to guarantee the detection of a given magnitude of damage growth.

Galvagni, A.; Cawley, P.

2013-01-01

376

Training mentally retarded adolescents to brush their teeth.  

PubMed Central

The need for self-care by retarded individuals in behaviors such as brushing teeth led to the development and evaluation of a comprehensive toothbrushing program that included a task analysis and training procedure specific to each component of the task analysis. Eight mentally retarded adolescents, in two groups, individually received acquisition training that included scheduled opportunities for independent performances, verbal instruction, modelling, demonstration, and physical assistance. The first group of four subjects received token plus social reinforcement; the second received only social reinforcement. All eight subjects showed improved toothbrushing behaviors when compared to baseline. Six of the eight subjects correctly performed all toothbrushing steps in two of three consecutive sessions. The study emphasizes the need for systematic program development and evaluation. PMID:1184494

Horner, R D; Keilitz, I

1975-01-01

377

Topical application of antibiotics in primary teeth: an overview.  

PubMed

Root canal infections are polymicrobial in nature, consisting of both aerobic and anaerobic species. The successful treatment of both primary and secondary endodontic infections involves effective eradication of the causative microorganisms during root canal treatment procedures. Reduction and elimination of microorganisms from the infected root canal provides optimal opportunity for treatment success. Local application of antibiotics has been considered an effective way to deliver antibiotics. A combination of antibiotic drugs have been tried under the concept of lesion sterilization and tissue repair therapy to eliminate the target bacteria, which are possible sources of endodontic lesions. The purpose of this article is to discuss the lesion sterilization and tissue repair therapy technique in primary teeth. PMID:24011295

Kayalvizhi, Gurusamy; Subramaniyan, Balaji; Suganya, Gurusamy

2013-01-01

378

Esthetic rehabilitation of anterior teeth with laminates composite veneers.  

PubMed

No- or minimal-preparation veneers associated with enamel preservation offer predictable results in esthetic dentistry; indirect additive anterior composite restorations represent a quick, minimally invasive, inexpensive, and repairable option for a smile enhancement treatment plan. Current laboratory techniques associated with a strict clinical protocol satisfy patients' restorative and esthetic needs. The case report presented describes minimal invasive treatment of four upper incisors with laminate nanohybrid resin composite veneers. A step-by-step protocol is proposed for diagnostic evaluation, mock-up fabrication and trial, teeth preparation and impression, and adhesive cementation. The resolution of initial esthetic issues, patient satisfaction, and nice integration of indirect restorations confirmed the success of this anterior dentition rehabilitation. PMID:25013730

Re, Dino; Augusti, Gabriele; Amato, Massimo; Riva, Giancarlo; Augusti, Davide

2014-01-01

379

Role of alcohol in the fracture resistance of teeth.  

PubMed

Healthy dentin, the mineralized tissue that makes up the bulk of the tooth, is naturally hydrated in vivo; however, it is known that various chemical reagents, including acetone and ethanol, can induce dehydration and thereby affect its properties. Here, we sought to investigate this in light of the effect of alcohol on the mechanical properties of dentin, specifically by measuring the stiffness, strength, and toughness of dentin in simulated body fluid and Scotch whisky. Results indicated that chemical dehydration induced by the whisky had a significant beneficial effect on the elastic modulus, strength, and fracture toughness of dentin. Although this made teeth more resistant to fracture, the change in properties was fully reversible upon rehydration. This effect is considered to be associated with increased cross-linking of the collagen molecules from intermolecular hydrogen-bonding, where water is replaced with weaker hydrogen-bond-forming solvents such as alcohol. PMID:17062743

Nalla, R K; Kinney, J H; Tomsia, A P; Ritchie, R O

2006-11-01

380

Causes and prevalence of traumatic injuries to the permanent incisors of school children aged 10-14 years in Maseru, Lesotho.  

PubMed

Traumatic dental injuries are widespread in the population and the prevalence of traumatic dental injuries among school children in different parts of the world varies from about 3% to 45%. Most injuries involve the anterior teeth, which may lead to eating restrictions, changes in physical appearance, speech defects and psychological impacts that affect the child's quality of life. A cross-sectional survey was carried out to investigate the prevalence, aetiology and types of injuries to permanent incisors among schoolchildren aged 10-14 years from Maseru, Lesotho. Upper and lower permanent incisors were examined for dental injuries. The prevalence of traumatic injuries to the permanent incisor teeth was 9.3% (13.3% boys and 6.3% girls). Significantly more boys than girls suffered injury. The most common type of injury was enamel fractures and most common cause was falls. Health promotion policies should aim to create an appropriate and safe environment for children. Soft playground surfaces, school-crossing patrols, marked zebra crossings and bicycle lanes would help create a safe environment. Speed limits for cars and the use of seat belts, air bags, special car seats for children and bicycle helmets should be enforced. Mouth guards should be used when playing sport, in particular contact sports. Education regarding the epidemiology of dental injuries and their prevention through health promotion may play a major role in reducing the prevalence of dental injury and avoiding the financial costs of treatment, especially in developing countries. PMID:18689347

Lin, H; Naidoo, Sudeshni

2008-04-01

381

Custom Metal Occlusal Surface for Acrylic Resin Denture Teeth to Enhance Wear Resistance: A Case Report  

PubMed Central

Wear of the occlusal surface of the denture is a known fact which leads to subsequent changes in jaw relation, vertical dimension, loss of aesthetics, aged looks, and decrease in masticatory efficiency. Treatment modalities includes, change of denture set after a regular interval of 4-5 years, use of wear resistant denture teeth that includes wear resistant resin or porcelain teeth, teeth with cast metal occlusal surface, and altering occlusal contact areas of denture teeth by use of silver amalgam fillings. A case report of a patient who had increased tendency of occlusal wear was treated with custom made metal occlusal surface of denture teeth to enhance wear resistance and to improve the masticatory efficiency. PMID:22997592

Shivji, Rizwan Ali; Kamble, Vaibhav D.; Khan, Mohd. Atif

2012-01-01

382

Polycarbonate crowns for primary teeth revisited: restorative options, technique and case reports.  

PubMed

Esthetics by definition is the science of beauty - that particular detail of an animate or inanimate object that makes it appealing to the eye. In the modern, civilized, and cosmetically conscious world, well-contoured and well-aligned white teeth set the standard for beauty. Such teeth are not only considered attractive but are also indicative of nutritional health, self esteem, hygienic pride, and economic status. Numerous treatment approaches have been proposed to address the esthetics and retention of restorations in primary teeth. Even though researchers have claimed that certain restorations are better than the others, particularly owing to the issues mentioned above, the search for the ideal esthetic restoration for the primary teeth continues. This paper revisits and attempts to reintroduce the full coverage restoration, namely, polycarbonate crown, for use in primary anterior teeth. PMID:24739917

Venkataraghavan, Karthik; Chan, John; Karthik, Sandhya

2014-01-01

383

Finding an alternative to formalin for sterilization of extracted teeth for teaching purposes.  

PubMed

Formalin is a known carcinogen, so there is a need to establish whether a safer alternative is available for the sterilization of human teeth destined for use in clinical training. Any disinfectant that is not capable of sterilizing 100 percent of the samples tested should be considered a failure. In this study, biofilms of oral bacteria were grown on previously autoclaved extracted human teeth. These biofilm-laden teeth were then screened against a range of disinfectants for an exposure time of seven days in a laboratory refrigerator. Culture methods were employed to validate the sterility of the tooth samples. Five percent Virkon and Gigasept PA proved effective against the laboratory model of disinfection and were carried forward to challenge freshly extracted human teeth. Gigasept PA was the only disinfectant that sterilized 100 percent of the tooth samples. Gigasept PA should be considered a safer and effective alternative to formalin for the sterilization of extracted teeth destined for teaching purposes. PMID:23314468

Hope, Christopher K; Griffiths, David A; Prior, Daniel M

2013-01-01

384

Detection and molecular characterisation of bovine polyomavirus in bovine sera in New Zealand  

Microsoft Academic Search

AIM: To investigate the prevalence of bovine polyomavirus (BPyV) DNA in commercial batches of bovine serum products, cell lines and cattle in New Zealand and to characterise the viral DNA detected.METHODS: Two nested polymerase chain reaction (PCR) assays were applied to detect BPyV in bovine sera. One was used to screen for the VP1 gene of BPyV DNA in: 140

J Wang; GW Horner; JS OKeefe

2005-01-01

385

PERMANENT RESIDENCE EMPLOYMENT-BASED SECOND  

E-print Network

of the dates that the advertisement appears. 8. Career Center recruitment - Post the job advertisement. The department must conduct a recruitment that will satisfy U.S. Department of Labor regulations for filing an application for permanent labor certification. The recruitment involves the following: 1. Prevailing wage

386

PERMANENT RESIDENCE EMPLOYMENT-BASED SECOND  

E-print Network

that the advertisement appears. 8. Career Center recruitment - Post the job advertisement with the FSU Career Center. You. The department must conduct a recruitment that will satisfy U.S. Department of Labor regulations for filing an application for permanent labor certification. The recruitment involves the following: 1. Prevailing wage

387

Searches for Permanent Electric Dipole Moments (EDM)  

E-print Network

(~10-11 at T=30 K) Ultra-Cold Neutrons (UCN) The ILL UCN Source Materials used for UCN storage: #12;The SQUIDs to detect 3He spin precession 3He capture/4He scintillation detection #12;UCN Source #12;NeutronSearches for Permanent Electric Dipole Moments (EDM) of Atoms, Molecules, and the Neutron Dmitry

Pines, Alexander

388

Rare earth-iron-boron-permanent magnets  

Microsoft Academic Search

This patent describes a neodymium-iron-boron permanent magnet containing added rare earth oxide. It is prepared by the method of comprising the steps of: mixing together components: a particulate alloy consisting essentially of neodymium, iron, cobalt, and boron; and a particulate rare earth oxide selected from the group consisting of gadolinium oxide, terbium oxide, dysprosium oxide, holmium oxide, and mixtures thereof;

Ghandehari

1990-01-01

389

Design Formulas for Permanent-Magnet Bearings  

Microsoft Academic Search

The development of high-energy product permanent magnet ~PM! materials has made PM magnetic bearings an attractive op- tion for applications ranging from turbo machinery to energy- storage flywheels. In small high-speed turbo compressors, bearing longevity is a problem that can be resolved with PM magnetic bearings. In space instrument applications, magnetic bearings eliminate the need for lubricants, which can contaminate

Brad Paden; Nelson Groom; James F. Antaki

2008-01-01

390

Lowering the Permanent Rate of Unemployment.  

ERIC Educational Resources Information Center

The first section of the study on lowering the permanent rate of unemployment discusses the effects and limitations of increasing aggregate demand through fiscal and monetary policy and indicates the inability to achieve the desired level of unemployment simply by stimulating demand. Section 2 analyzes the characteristics and structure of our…

Feldstein, Martin S.

391

The “lost” passages of permanence and change  

Microsoft Academic Search

Students of Kenneth Burke's writing should be aware that the editions of Permanence and Change in print are significantly different from the original version published in 1935. This article identifies the most important changes and reproduces certain passages from the original edition concerning communism and capitalism that were cut from all subsequent editions. The various syntactic changes, alterations in word

Edward Schiappa; Mary F. Keehner

1991-01-01

392

Modified asphalt mixtures resistance to permanent deformations  

Microsoft Academic Search

Permanent deformations, primarily in the form of ruts, are one of the basic asphalt pavement damages impairing its service properties. Application of appropriate asphalt mixtures and binder modification are effective methods for improving asphalt courses resistance. While being manufactured, stored, fitted into a road pavement and during long term service, bitumen binders and asphalt mixtures are subject to continuous unfavourable

Piotr Radziszewski

2007-01-01

393

Core losses in permanent magnet motors  

Microsoft Academic Search

It is pointed out that the conventional approach to core loss prediction using the Fourier series of the space wave of air gap flux density is not applicable to surface mounted permanent magnet (PM) motors. An alternative approach based on the concept that eddy current losses are proportional to the square of the time rate of change of the flux

G. R. Slemon; X. Liu

1990-01-01

394

Cogging Torque Reduction in Permanent Magnet Machines  

Microsoft Academic Search

This paper examines two methods - magnet shifting and optimizing the magnet pole arc - for reducing cogging torque in permanent magnet machines. The methods were applied to existing machine designs and their performance was calculated using finite-element analysis (FEA). Prototypes of the machine designs were constructed and experimental results obtained. It is shown that the FEA predicted the cogging

Luke Dosiek; Pragasen Pillay

2007-01-01

395

Saturated hydrocarbons in bovine liver  

PubMed Central

A homologous series of n-alkanes (C14–C33) and two isoprenoid hydrocarbons, 2,6,10,14-tetramethylhexadecane (phytane) and 2,6,10,14-tetramethylpentadecane (pristane) have been identified in bovine liver. Another branched but non-isoprenoid alkane and three isomers of molecular formula C20H40 were partially identified. Phytane and the C18–C22 and C29–C33 n-alkanes were found to be the major components in liver, suggesting that at least the main hydrocarbon components were derived from various plants in the diet. The hydrocarbons were separated and identified by a series of steps involving solvent extraction, saponification, elution chromatography on alumina and silica gel columns, molecular sieving and by infrared and ultraviolet spectroscopy, followed by combined capillary gas chromatography–mass spectrometry. PMID:5820649

Nagy, Bartholomew; Modzeleski, Vincent E.; Scott, Ward M.

1969-01-01

396

Bovine Mastitis: Frontiers in Immunogenetics  

PubMed Central

Mastitis is one of the most prevalent and costly diseases in the dairy industry with losses attributable to reduced milk production, discarded milk, early culling, veterinary services, and labor costs. Typically, mastitis is an inflammation of the mammary gland most often, but not limited to, bacterial infection, and is characterized by the movement of leukocytes and serum proteins from the blood to the site of infection. It contributes to compromised milk quality and the potential spread of antimicrobial resistance if antibiotic treatment is not astutely applied. Despite the implementation of management practises and genetic selection approaches, bovine mastitis control continues to be inadequate. However, some novel genetic strategies have recently been demonstrated to reduce mastitis incidence by taking advantage of a cow’s natural ability to make appropriate immune responses against invading pathogens. Specifically, dairy cattle with enhanced and balanced immune responses have a lower occurrence of disease, including mastitis, and they can be identified and selected for using the high immune response (HIR) technology. Enhanced immune responsiveness is also associated with improved response to vaccination, increased milk, and colostrum quality. Since immunity is an important fitness trait, beneficial associations with longevity and reproduction are also often noted. This review highlights the genetic regulation of the bovine immune system and its vital contributions to disease resistance. Genetic selection approaches currently used in the dairy industry to reduce the incidence of disease are reviewed, including the HIR technology, genomics to improve disease resistance or immune response, as well as the Immunity+™ sire line. Improving the overall immune responsiveness of cattle is expected to provide superior disease resistance, increasing animal welfare and food quality while maintaining favorable production levels to feed a growing population. PMID:25339959

Thompson-Crispi, Kathleen; Atalla, Heba; Miglior, Filippo; Mallard, Bonnie A.

2014-01-01

397

Bovine calves as ideal bio-indicators for fluoridated drinking water and endemic osteo-dental fluorosis.  

PubMed

Relative susceptibility to fluoride (F) toxicosis in the form of osteo-dental fluorosis was observed in an observational survey of 2,747 mature and 887 immature domestic animals of diverse species living in areas with naturally fluoridated (>1.5 ppm F) drinking water. These animals included buffaloes (Bubalus bubalis), cattle (Bos taurus), camels (Camelus dromedarius), donkeys (Equus asinus), horses (Equus caballus), goats (Capra hircus), and sheep (Ovis aries). Of these mature and immature animals, 899 (32.7 %) and 322 (36.3 %) showed evidence of dental fluorosis with varying grades, respectively. Their incisor teeth were stained with light to deep brownish color. On clinical examination, 31.2 % mature and 10.7 % immature animals revealed periosteal exostoses, intermittent lameness, and stiffness of tendons in the legs as signs of skeletal fluorosis. The maximum susceptibility to fluoride toxicosis was found in bovines (buffaloes and cattle) followed by equines (donkeys and horses), flocks (goats and sheep), and camelids (camels). The bovine calves were found to be more sensitive and highly susceptible to F toxicosis and revealed the maximum prevalence (92.2 %) of dental fluorosis. This indicates that bovine calves are less tolerant and give early sign of F poisoning (dental fluorosis) and therefore, they can be considered as bio-indicators for fluoridated water as well as for endemicity of osteo-dental fluorosis. Causes for variation in susceptibility to F toxicosis (fluorosis) in various species of domestic animal are also discussed. PMID:24671615

Choubisa, S L

2014-07-01

398

A Correlation of Permanent Anterior Tooth Fracture with Type of Occlusion and Craniofacial Morphology  

PubMed Central

ABSTRACT Aims: To assess the relationship of anterior tooth fractures with type of occlusion and craniofacial morphology. Materials and methods: The study was conducted on 76 subjects of age group 9 to 13 years with at least one fractured permanent anterior teeth. Lateral cephalograms were taken and study models were prepared for each subject with prior consent of their parents. Then cephalometric tracings were done and overjet was recorded through study models. Statistical analysis used: Standard error of mean (SEM) and unpaired t-test has been applied to test the significant difference between the seven parameters under consideration. Karl Pearson correlation test has also been used to correlate all the parameters used in this study with each other. All the tests were performed at 5 and 1% levels of significance. Results: Frequency of tooth fracture increases with increasing overjet. At 5% level of significance, significant difference were observed between the standard values and observed values for overjet measurement, SNA angle, SNB angle, ANB angle, upper incisor to NA (angle), upper incisor to NA (linear) and interincisal angle for overall data and also for both male and female data separately. Conclusion: Probability of permanent anterior tooth fracture increases with increasing overjet. A significant difference was observed between the standard value and the observed values of all parameters under consideration. How to cite this article: Chaturvedi R, Kumar A, Rana V, Aggarwal A, Chandra L. A Correlation of Permanent Anterior Tooth Fracture with Type of Occlusion and Craniofacial Morphology. Int J Clin Pediatr Dent 2013;6(2):80-84.

Kumar, Ashish; Rana, Vivek; Aggarwal, Abhai; Chandra, Lokesh

2013-01-01

399

Growth of stylolite teeth patterns depending on normal stress and finite Daniel Koehn, Francois Renard, Renaud Toussaint, Cees W. Passchier  

E-print Network

Ã?Ã? Ã? Ã?Ã?Ã? Ã? Ã?Ã? Growth of stylolite teeth patterns depending on normal stress and finite compaction this article as: Daniel Koehn, Francois Renard, Renaud Toussaint, Cees W. Passchier, Growth of stylolite teeth ACCEPTED MANUSCRIPT - 1 - Growth of stylolite teeth patterns depending on normal stress and1 finite

Toussaint, Renaud

400

PRESLA: An Original Device to Measure the Mechanical Interaction between Tongue and Teeth or Palate during Speech Production  

E-print Network

PRESLA: An Original Device to Measure the Mechanical Interaction between Tongue and Teeth or Palate experimental procedure is presented to measure the mechanical interaction between tongue and teeth and palate such as the palate or the teeth to induce specific strains in the tongue and to increase speech movement accuracy

Paris-Sud XI, Université de

401

Temporal trend of mercury in polar bears (Ursus maritimus) from4 Svalbard using teeth as a biomonitoring tissue5  

E-print Network

1 1 2 3 Temporal trend of mercury in polar bears (Ursus maritimus) from4 Svalbard using teeth and carbon stable isotopes in teeth of polar bear29 (Ursus maritimus) from Svalbard as biotracers of temporal changes in Hg pollution exposure30 between 1964 and 2003. Teeth were regarded as a good matrix of the Hg

Paris-Sud XI, Université de

402

American Journal of Botany 96(4): 738750. 2009. The sensitivity of leaf teeth to climate is well known and  

E-print Network

738 American Journal of Botany 96(4): 738­750. 2009. The sensitivity of leaf teeth to climate and number of teeth also correlate negatively with MAT (Huff et al., 2003; Royer et al., 2005, 2008). However, despite leaf teeth being strongly linked to temperature, less is known about their sensitivity to most

Royer, Dana

403

PII S0016-7037(99)00376-2 Fossil fish teeth as proxies for seawater Sr and Nd isotopes  

E-print Network

PII S0016-7037(99)00376-2 Fossil fish teeth as proxies for seawater Sr and Nd isotopes E. E. MARTIN) Abstract--We analyzed Nd and Sr isotopic compositions of Neogene fossil fish teeth from two sites of seawater isotopic values. Sr is incorporated into the teeth at the time of growth; thus Sr isotopes

Martin, Ellen

404

Immunohistochemical Localization of LIM Mineralization Protein 1 in Pulp–Dentin Complex of Human Teeth with Normal and Pathologic Conditions  

Microsoft Academic Search

LIM mineralization protein 1 (LMP-1) is an essential positive regulator of osteoblast differentiation and maturation and bone formation. However, the expression and distribution of LMP-1 in human teeth are largely unknown. The aim of this study was to detect the expression of LMP-1 in normal healthy human teeth and human teeth with various pathologic conditions. LMP-1 expression was determined by

Xiaoying Wang; Qi Zhang; Zhi Chen; Lu Zhang

2008-01-01

405

Original article Hyperimmune bovine colostrum treatment  

E-print Network

. / cryptosporidiosis / oocyst / hyperimmune bovine colostrum / gecko * Correspondence and reprints Tel.: ( 1 ) 410 614 and efficacious in clinical and sub- clinical cryptosporidiosis in snakes [ 1 3 we The high morbidity and frequent

Paris-Sud XI, Université de

406

Aerosol stability of bovine adenovirus type 3.  

PubMed Central

The WBR-1 strain of bovine adenovirus type 3 was suspended in Eagle's medium or bovine nasal secretion and atomized into a rotating drum at temperatures of 6 degrees C or 32 degrees C and relative humidities of 30% or 90%. Impinger samples of the aerosols were collected seven minutes, one, two and three hours postgeneration, and titrated for infectivity in embryonic bovine kidney cell cultures. Under certain conditions of temperature and relative humidity, the virus was more stable in aerosols of Eagle's medium than in nasal secretion. The bovine adenovirus was usually inactivated more rapidly at 30% relative humidity than at 90% relative humidity and during aging of the aerosols the virus was inactivated more rapidly at 32 degrees C than at 6 degrees C. PMID:226247

Elazhary, M A; Derbyshire, J B

1979-01-01

407

Characterization of the Bovine Cathelicidin Gene Family  

E-print Network

, chemotactic activity, and apoptosis. Thus, comprehensive characterizing of bovine CATHLs could potentially identify underlying inherited differences in innate immunity and disease resistance in cattle. The purpose of the present study was to verify...

Flores, Erin Gillenwaters

2012-10-19

408

Bovine enteroviruses: classification and serological characterization  

E-print Network

BOVINE ENTEROVIRUSES: CLASS IF ICATION AND SEROLOGICAL CHARACTERIZATION A Thesis by SIBA KUMAR SAMAL Submitted to the Graduate College of Texas A&M Uni vers i ty in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... August 1981 Major Subject: Veterinary Microbiology BOVINE ENTEROVIRUSES: CLASSIFICATION AND SEROLOGICAL CHARACTERIZATION A Thesis by SIBA KUMAR SAMAL Approved as to style and content by: Chairman o Committee Hem er Nem e Head of Oepartment...

Samal, Siba Kumar

2012-06-07

409

Microinjection of spermatozoa into bovine eggs  

E-print Network

MICROINJECTION OF SPERMATOZOA INTO BOVINE EGGS A Thesis by MARK EDWARD WESTHUSIN Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1983 Major... Subject: Veterinary Physiology MICROINJECTION OP SPERMATOZOA INTO BOVINE EGGS A Thesis by MARK EDWARD WESTHUSIN Approved as to style and content by: Duane C. raemer (Chairman of Committee) Paul G. Harms (Member) James G ~ Anderson (Member...

Westhusin, Mark Edward

2012-06-07

410

Vinegar as a disinfectant of extracted human teeth for dental educational use  

PubMed Central

Context: Extracted human teeth are routinely used in dentistry to learn technical and preclinical skills. Centers for Disease Control and Prevention (CDC) has adopted guidelines for infection control of extracted teeth used for research and teaching, requiring that teeth be sterilized before use. Many of the proposed disinfection methods starting from use of formalin, sodium hypochlorite and to autoclaving have their own drawbacks and may not be practical. Aim: To assess the effectiveness of vinegar for disinfection/sterilization of extracted human teeth. Materials and Methods: A total of 80 extracted non-carious human teeth were kept in seven disinfectant media—10% formalin, 3% hydrogen peroxide, 5.25% sodium hypochlorite, 70% alcohol, vinegar, neem extract and normal saline. Ten samples were placed in each disinfectant individually for a period of 7 days, at room temperature. In all, 10 teeth were treated with microwave irradiation at 650 W for 3 min. Later, teeth from each group were placed individually in separate test tubes containing 10 ml of tryptic soy broth at 37°C for 48 h to observe the evidence of growth of microorganisms. Semiquantitative analysis of all the samples was done in Clade agar at 37°C for 48 h. Statistical Analysis Used: The number of teeth disinfected in each group was compared using Chi square test. Results: 10% formalin, 3% hydrogen peroxide and vinegar were totally effective. The result was statistically significant with a Chi square value of 61.414 and P < 0.001. Conclusions: Vinegar can be used as an effective disinfectant medium for extracted human teeth. PMID:24959031

Tijare, Manisha; Smitha, D; Kasetty, Sowmya; Kallianpur, Shreenivas; Gupta, Sandeep; Amith, HV

2014-01-01

411

Incidence of invasive cervical resorption in bleached root-filled teeth.  

PubMed

Invasive cervical resorption, a form of external root resorption, has been reported to be associated with intra-coronal bleaching of root-filled teeth and this has raised concerns about carrying out such bleaching procedures. The purpose of the present study was to examine the incidence of invasive cervical resorption in root-filled teeth which had been bleached using a standardized technique. Three observers examined records and radiographs from a total of 158 patients, whose bleaching treatment had been carried out in a specialist endodontic practice. The sample comprised 204 teeth with a review period of between 1 and 19 years. One-hundred-and-fifty-one teeth (77.94 per cent) had an associated history of traumatic injury. All teeth had been treated with a combination of thermocatalytic and 'walking bleach' procedures using 30 per cent hydrogen peroxide. In 54.41 per cent of teeth, gutta-percha and AH26 root-fillings were kept at the height of the cemento-enamel junction while 18.63 per cent were below and 26.96 per cent were above the CEJ. Sealing cement was not placed over the gutta-percha and AH26 root-fillings in any of the teeth in the study. It was found that a total of four teeth from the sample group (1.96 per cent) had developed invasive cervical resorption during the review period. All of these teeth had a history of traumatic injury and the level of gutta-percha was at the CEJ.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8018064

Heithersay, G S; Dahlstrom, S W; Marin, P D

1994-04-01

412

Psychosocial factors and work related sickness absence among permanent and non-permanent employees  

PubMed Central

Study objective: To examine the association between psychosocial work factors and work related sickness absence among permanent and non-permanent employees by sex. Design: A cross sectional survey conducted in 2000 of a representative sample of the European Union total active population, aged 15 years and older. The independent variables were psychological job demands and job control as measures of psychosocial work environment, and work related sickness absence as the main outcome. Poisson regression models were used to compute sickness absence days' rate ratios. Setting: 15 countries of the European Union. Participants: A sample of permanent (n = 12 875) and non-permanent (n = 1203) workers from the Third European Survey on Working Conditions. Results: High psychological job demands, low job control, and high strain and passive work were associated with higher work related sickness absence. The risks were more pronounced in non-permanent compared with permanent employees and men compared with women. Conclusions: This work extends previous research on employment contracts and sickness absence, suggesting different effects depending on psychosocial working conditions and sex. PMID:15365115

Gimeno, D.; Benavides, F.; Amick, B.; Benach, J.; Martinez, J. M.

2004-01-01

413

Rehabilitation of severely mutilated teeth under general anesthesia in an emotionally immature child.  

PubMed

Dental caries is the single most common chronic childhood disease. In rampant caries, there is early pulp involvement and gross destruction of the maxillary anterior teeth as well as posterior teeth. This leads to decreased masticatory efficiency, difficulty in speech, compromised esthetics, development of abnormal tongue habits and subsequent malocclusion and psychological problems. The restoration of severely decayed primary incisors is often a procedure that presents a special challenge to dentists, particularly in an uncooperative child. This case report documents the restoration of severely mutilated deciduous teeth in an emotionally immature patient under general anesthesia. PMID:20215672

Navit, S; Katiyar, A; Samadi, F; Jaiswal, J N

2010-01-01

414

Attitudes towards replacement of teeth among patients at the Institute of Dental Sciences, Belgaum, India.  

PubMed

The purpose of this study was to assess the attitude towards replacement of teeth among patients who reported to the department of prosthodontics in the Institute of Dental Sciences, Belgaum, which is located in the northwestern part of the state of Karnataka in the southern region of India. A fourteen-item, closed-ended questionnaire was completed by 365 volunteer patients who were then examined by a clinician and existing and missing teeth were charted. All the patients who reported to a dental clinic in a period of two months with at least one missing tooth were included in the study. Collected data were statistically analyzed using chi-square test at a significance level of p<0.05. The age of the subjects ranged from sixteen to eighty-four years (mean age 51.06 +/-16.47 years). Among these 365 patients, 228 were in a waiting period for soft tissue healing after extraction of tooth/teeth; 19.7 percent of the patients gave financial constraints as the reason for not replacing teeth; 7.1 percent reported that they lacked the time to have teeth replaced; 6.9 percent had low felt needs; and 3.8 percent indicated they did not know that teeth could be replaced. Subjects with different levels of socioeconomic status reported different reasons for not replacing the teeth and these differences were statistically significant (chi(2)=61.16, P<0.001). Knowledge about the equivalence of artificial teeth with natural teeth (chi(2)=23.01, P<0.05) and problems with artificial teeth (chi(2)=17.25, P<0.05) were also significantly different among subjects from different socioeconomic categories. The findings indicate that awareness needs to be increased regarding the other functions of teeth like esthetics and phonetics because many subjects in this study were only aware of the function of mastication performed by teeth, especially among individuals in the lower socioeconomic group. Attitudes of patients should be taken into consideration to improve patient compliance with and acceptance of prostheses. PMID:17971577

Shigli, Kamal; Hebbal, Mamata; Angadi, Gangadhar Shivappa

2007-11-01

415

Opal phytoliths found on the teeth of the extinct ape Gigantopithecus blacki: implications for paleodietary studies.  

PubMed Central

Identification of opal phytoliths bonded to the enamel surface of the teeth of Gigantopithecus blacki indicates that this extinct ape had a varied diet of grasses and fruits. By using the scanning electron microscope at magnifications of 2000-6000x specific opal phytoliths were observed and photographed on the fossilized teeth of an extinct species. Since opal phytoliths represent the inorganic remains of once-living plant cells, their documentation on the teeth of Gigantopithecus introduces a promising technique for the determination of diet in extinct mammalian species which should find numerous applications in the field of paleoanthropology as well as vertebrate paleontology. Images PMID:2236026

Ciochon, R L; Piperno, D R; Thompson, R G

1990-01-01

416

Emerging permanent filler technologies: focus on Aquamid  

PubMed Central

A plethora of soft tissue fillers have been developed within the past decade to correct the cutaneous changes that occur with photoaging. Such fillers, whether nonpermanent, semipermanent, or permanent, are widely used to fill undesired facial rhytides. In addition, fillers are employed to correct atrophy of the face as well as other parts of the body such as the dorsum of the hands through volumization and contouring. The extensive long-term safety outcomes reported with fillers and the ease with which they are administered make them an ideal choice to correct rhytides and to contour the face. However, as with any cosmetic procedure, in order to ensure high patient satisfaction and a safe outcome, proper training in injection techniques, the choice of the proper candidate, and awareness of potential adverse events are essential. This review article focuses on the permanent filler, Aquamid, which is composed of polyacrylamide hydrogel. PMID:25336982

Yamauchi, Paul S

2014-01-01

417

Permanent genetic memory with >1-byte capacity.  

PubMed

Genetic memory enables the recording of information in the DNA of living cells. Memory can record a transient environmental signal or cell state that is then recalled at a later time. Permanent memory is implemented using irreversible recombinases that invert the orientation of a unit of DNA, corresponding to the [0,1] state of a bit. To expand the memory capacity, we have applied bioinformatics to identify 34 phage integrases (and their cognate attB and attP recognition sites), from which we build 11 memory switches that are perfectly orthogonal to each other and the FimE and HbiF bacterial invertases. Using these switches, a memory array is constructed in Escherichia coli that can record 1.375 bytes of information. It is demonstrated that the recombinases can be layered and used to permanently record the transient state of a transcriptional logic gate. PMID:25344638

Yang, Lei; Nielsen, Alec A K; Fernandez-Rodriguez, Jesus; McClune, Conor J; Laub, Michael T; Lu, Timothy K; Voigt, Christopher A

2014-12-01

418

Evaluation of permanently charged electrofibrous filters  

SciTech Connect

These studies showed that loading the permanently charged filters with captured aerosols will lead to a neutralization of the filter charge. The transfer from the captured aerosol to the fiber surface and the subsequent neutralization of fiber charge. The increased efficiency is due to the additional mechanical capture by the particle deposits. The minimum efficiency obtained during the loading of solid aerosols is determined by the aerosol charge, with highly charged aerosols producing a lower minimum. Permanently charged filters lose their fiber charge when exposed to organic solvents or ionic water solutions. The fiber charge neutralization was minimized by coating the charged fibers with a polymer. Several different coating techniques were examined. Unfortunately, preventing the neutralization of fiber charge is not sufficient to prevent a deterioration of filter efficiency.

Biermann, A.H.; Lum, B.Y.; Bergman, W.

1982-10-18

419

Immune therapeutic potential of stem cells from human supernumerary teeth.  

PubMed

Discoveries of immunomodulatory functions in mesenchymal stem cells (MSCs) have suggested that they might have therapeutic utility in treating immune diseases. Recently, a novel MSC population was identified from dental pulp of human supernumerary teeth, and its multipotency characterized. Herein, we first examined the in vitro and in vivo immunomodulatory functions of human supernumerary tooth-derived stem cells (SNTSCs). SNTSCs suppressed not only the viability of T-cells, but also the differentiation of interleukin 17 (IL-17)-secreting helper T (Th17)-cells in in vitro co-culture experiments. In addition, systemic SNTSC transplantation ameliorated the shortened lifespan and elevated serum autoantibodies and nephritis-like renal dysfunction in systemic lupus erythematosus (SLE) model MRL/lpr mice. SNTSC transplantation also suppressed in vivo increased levels of peripheral Th17 cells and IL-17, as well as ex vivo differentiation of Th17 cells in MRL/lpr mice. Adoptive transfer experiments demonstrated that SNTSC-transplanted MRL/lpr mouse-derived T-cell-adopted immunocompromised mice showed a longer lifespan in comparison with non-transplanted MRL/lpr mouse-derived T-cell-adopted immunocompromised mice, indicating that SNTSC transplantation suppresses the hyper-immune condition of MRL/lpr mice through suppressing T-cells. Analysis of these data suggests that SNTSCs are a promising MSC source for cell-based therapy for immune diseases such as SLE. PMID:23697344

Makino, Y; Yamaza, H; Akiyama, K; Ma, L; Hoshino, Y; Nonaka, K; Terada, Y; Kukita, T; Shi, S; Yamaza, T

2013-07-01

420

Determining Fetal Manganese Exposure from Mantle Dentine of Deciduous Teeth  

PubMed Central

Studies addressing health effects of manganese (Mn) excess or deficiency during prenatal development are hampered by a lack of biomarkers that can reconstruct fetal exposure. We propose a method using the neonatal line, a histological feature in deciduous teeth, to identify regions of mantle dentine formed at different prenatal periods. Micro-measurements of Mn in these regions may be used to reconstruct exposure at specific times in fetal development. To test our hypothesis, we recruited pregnant women before 20 weeks gestation from a cohort of farmworkers exposed to Mn-containing pesticides. We collected house floor dust samples and mother’s blood during the second trimester; umbilical cord blood at birth; and shed deciduous incisors when the child was ~7 years of age. Mn levels in mantle dentine formed during the second trimester (as 55Mn:43Ca area under curve) were significantly associated with floor dust Mn loading (rspearman=0.40; p=0.0005; n=72). Furthermore, 55Mn:43Ca in sampling points immediately adjacent the neonatal line were significantly associated to Mn concentrations in cord blood (rspearman=0.70; p=0.003; n=16). Our results support that Mn levels in mantle dentine are useful in discerning perinatal Mn exposure, offering a potentially important biomarker for the study of health effects due to environmental Mn exposure. PMID:22455722

Arora, Manish; Bradman, Asa; Austin, Christine; Vedar, Michelle; Holland, Nina; Eskenazi, Brenda; Smith, Donald R.

2012-01-01

421

Washing and trypsin treatment of in vitro derived bovine embryos exposed to bovine viral diarrhea virus  

Microsoft Academic Search

Gametes, somatic cells and materials of animal origin in media are potential sources for introducing bovine viral diarrhea virus (BVDV) into systems for production of IVF bovine embryos. Further, the efficacy of washing and trypsin treatment for removal of BVDV from IVF embryos is questionable. Washing and trypsin treatments recommended by the International Embryo Transfer Society for in vivo-derived embryos

E Trachte; D Stringfellow; K Riddell; P Galik; M Riddell; J Wright

1998-01-01

422

Effects of fetal bovine serum, FSH and 17?-estradiol on the culture of bovine preantral follicles  

Microsoft Academic Search

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant FSH and 17?-estradiol on the morphology and growth of the preantral follicles was investigated in medium without FBS. After culture in medium with 10% FBS, the increase

S. C. J. Hulshof; J. R. Figueiredo; J. F. Beckers; M. M. Bevers; J. A. van der Donk; R. van den Hurk

1995-01-01

423

Amino acid metabolism of preimplantation bovine embryos cultured with bovine serum albumin or polyvinyl alcohol  

Microsoft Academic Search

Bovine serum albumin (BSA) is an embryotrophic macromolecule used in embryo culture media, which is commonly replaced with synthetic compounds, such as polyvinyl alcohol (PVA). This study compared the effect of BSA and PVA on the development, blastocyst cell number and amino acid metabolism of preimplantation bovine embryos in vitro. Embryos were produced by in vitro maturation and fertilization of

Nicolas M Orsi; Henry J Leese

2004-01-01

424

8 CFR 216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Definition of conditional permanent...DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONDITIONAL...RESIDENCE STATUS § 216.1 Definition of conditional permanent...immigrant in accordance with the immigration laws, such...

2010-01-01

425

8 CFR 216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Definition of conditional permanent...DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONDITIONAL...RESIDENCE STATUS § 216.1 Definition of conditional permanent...immigrant in accordance with the immigration laws, such...

2013-01-01

426

8 CFR 1216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Definition of conditional permanent resident...Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE...RESIDENCE STATUS § 1216.1 Definition of conditional permanent...

2010-01-01

427

8 CFR 1216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Definition of conditional permanent resident...Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE...RESIDENCE STATUS § 1216.1 Definition of conditional permanent...

2011-01-01

428

8 CFR 216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 false Definition of conditional permanent...DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONDITIONAL...RESIDENCE STATUS § 216.1 Definition of conditional permanent...immigrant in accordance with the immigration laws, such...

2012-01-01

429

8 CFR 1216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Definition of conditional permanent resident...Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE...RESIDENCE STATUS § 1216.1 Definition of conditional permanent...

2013-01-01

430

8 CFR 1216.1 - Definition of conditional permanent resident.  

...2014-01-01 2014-01-01 false Definition of conditional permanent resident...Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE...RESIDENCE STATUS § 1216.1 Definition of conditional permanent...

2014-01-01

431

8 CFR 1216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Definition of conditional permanent resident...Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE...RESIDENCE STATUS § 1216.1 Definition of conditional permanent...

2012-01-01

432

8 CFR 216.1 - Definition of conditional permanent resident.  

... 2014-01-01 false Definition of conditional permanent...DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONDITIONAL...RESIDENCE STATUS § 216.1 Definition of conditional permanent...immigrant in accordance with the immigration laws, such...

2014-01-01

433

8 CFR 216.1 - Definition of conditional permanent resident.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 false Definition of conditional permanent...DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS CONDITIONAL...RESIDENCE STATUS § 216.1 Definition of conditional permanent...immigrant in accordance with the immigration laws, such...

2011-01-01

434

25 CFR 20.511 - Should permanency plans be developed?  

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance Foster Care § 20.511 Should permanency plans be developed? Permanency planning must be...

2014-04-01

435

25 CFR 20.511 - Should permanency plans be developed?  

Code of Federal Regulations, 2011 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance Foster Care § 20.511 Should permanency plans be developed? Permanency planning must be...

2011-04-01

436

25 CFR 20.511 - Should permanency plans be developed?  

Code of Federal Regulations, 2010 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance Foster Care § 20.511 Should permanency plans be developed? Permanency planning must be...

2010-04-01

437

25 CFR 20.511 - Should permanency plans be developed?  

Code of Federal Regulations, 2013 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance Foster Care § 20.511 Should permanency plans be developed? Permanency planning must be...

2013-04-01

438

25 CFR 20.511 - Should permanency plans be developed?  

Code of Federal Regulations, 2012 CFR

...BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance Foster Care § 20.511 Should permanency plans be developed? Permanency planning must be...

2012-04-01

439

30 CFR 75.604 - Permanent splicing of trailing cables.  

Code of Federal Regulations, 2010 CFR

...STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.604 Permanent splicing of trailing cables. [Statutory Provisions...permanent splices in trailing cables are made, they shall be...Mechanically strong with adequate electrical conductivity and...

2010-07-01

440

Permanent Planning for Foster Children: The Oregon Project  

ERIC Educational Resources Information Center

Discusses the Oregon Foster Care Project, a 3-year demonstration project of the Freeing Children for Permanent Placement project funded by the Office of Child Development. Types of cases that present problems to permanent placement are presented. (SB)

Pike, Victor

1976-01-01

441

Physical indicators of hydrologic permanence in forested headwater streams  

EPA Science Inventory

Recent court cases have brought headwater streams and their hydrologic permanence into the forefront for regulatory agencies, so rapid field-based indicators of hydrologic permanence in streams are critically needed. Our study objectives were to 1) identify environmental charact...

442

27 CFR 22.68 - Notice of permanent discontinuance.  

...TREASURY ALCOHOL DISTRIBUTION AND USE OF TAX-FREE ALCOHOL Qualification Permanent Discontinuance of Use of Tax-Free Alcohol § 22.68 Notice...permittee who permanently discontinues the use of tax-free alcohol shall file a...

2014-04-01

443

Stability of permanent-magnet parameters  

NASA Astrophysics Data System (ADS)

Data are presented on the time, temperature, and radiation-stability characteristics of permanent magnets composed of barium ferrite, ALNICO alloys, and SmCo5. Magnetic characteristics are constant over a period of 10(4) to 10(5) h. Results are given on reversible and irreversible flux losses. It is concluded that these magnetic materials have a radiation stability similar to that of aluminum and stainless steel.

Ilyushchenko, V. I.

444

Rare earth-cobalt permanent magnets  

Microsoft Academic Search

This paper reviews the historical background and the development of rare earth-cobalt-based permanent magnets from basic science studies on rare earth-transition metal alloys in the 1960's to today's broad spectrum of commercial magnet types and their applications. It puts the RE-Co magnets in perspective relative to older magnet types and also traces the path to the subsequent development of the

Karl J. Strnat; Reinhold M. W. Strnat

1991-01-01

445

Freeze-branding to permanently mark bats  

Microsoft Academic Search

We tested the effectiveness of freeze-branding as a permanent marking technique on 4 species of bats: Brazilian free-tailed bat (Tadarida brasiliensis), Townsend's big-eared bat (Corynorhinus townsendil), big brown bat (Eptesicus fuscus), and western small-footed myotis (Myotis ciliolabrum). Small copper branding irons (9.3 g and 15.6 g) were cooled in a mixture of dry ice and ethyl alcohol and applied to

Richard E. Sherwin; Shauna Haymond; Rebeccah Olsen

446

"Permanence" - An Adaptationist Solution to Fermi's Paradox?  

NASA Astrophysics Data System (ADS)

A new solution of Fermi's paradox sketched by SF writer Karl Schroeder in his 2002. novel Permanence is investigated. It is argued that this solution is tightly connected with adaptationism - a widely discussed working hypothesis in evolutionary biology. Schroeder's hypothesis has important ramifications for astrobiology, SETI projects, and future studies. Its weaknesses should be explored without succumbing to the emotional reactions often accompanying adaptationist explanations.

Cirkovic, Milan M.

447

PERFORMANCE OF HYSTERESIS PERMANENT MAGNET MOTORS  

Microsoft Academic Search

There is an increasing interest in using permanent magnet (PM) hysteresis motors because of their superior performances over the conventional hysteresis motors. Recent NdBFe magnets have the advantages of higher magnetic energy product and remanence. It can develop significant accelerating torque during run-up and synchronization with limited temperature tolerance. The application of the NdBFe magnets in electrical machines Is attracting

A. M. OSHEIBA; J. QIAN; M. A. RAHMAN

1989-01-01

448

Permanent-magnet motors for brushless operation  

Microsoft Academic Search

The design considerations for permanent-magnet motors intended for brushless operation are discussed. Two rotor configurations are described: the imbricated rotor and the segmented rotor. The segmented rotor is designed specially for high-speed operation. A brushless DC (BLDC) drive system is also described, and the performance of a neodymium-iron-boron excited PM motor with an imbricated rotor in a BLDC drive is

TECK-SENG LOW; MOHAMMED A. JABBAR; M. AZIZUR RAHMAN

1990-01-01

449

Multi-phase permanent magnet motor drives  

Microsoft Academic Search

In this paper, a new five-phase brushless permanent magnet motor is proposed. The proposed motor has concentrated windings so the produced back-EMF is almost trapezoidal. The motor is supplied with the combined sinusoidal plus third harmonic of currents. For presenting the superior performance of the proposed five-phase motor, its three and five-phase counterparts are also analyzed. By changing the number

Leila Parsa; Hamid A. Toliyat

2003-01-01

450

When Do Commercial Reactors Permanently Shut Down?  

EIA Publications

For those wishing to obtain current data, the following resources are available: U.S. reactors, go to the Energy Information Administration's nuclear reactor shutdown list. (Note: As of April 30, 2010, the last U.S. reactor to permanently shut down was Big Rock Point in 1997.) Foreign Reactors, go to the Power Reactor Information System (PRIS) on the International Atomic Energy Agency's website.

2011-01-01

451

Retrosplenial Cortex Codes for Permanent Landmarks  

PubMed Central

Landmarks are critical components of our internal representation of the environment, yet their specific properties are rarely studied, and little is known about how they are processed in the brain. Here we characterised a large set of landmarks along a range of features that included size, visual salience, navigational utility, and permanence. When human participants viewed images of these single landmarks during functional magnetic resonance imaging (fMRI), parahippocampal cortex (PHC) and retrosplenial cortex (RSC) were both engaged by landmark features, but in different ways. PHC responded to a range of landmark attributes, while RSC was engaged by only the most permanent landmarks. Furthermore, when participants were divided into good and poor navigators, the latter were significantly less reliable at identifying the most permanent landmarks, and had reduced responses in RSC and anterodorsal thalamus when viewing such landmarks. The RSC has been widely implicated in navigation but its precise role remains uncertain. Our findings suggest that a primary function of the RSC may be to process the most stable features in an environment, and this could be a prerequisite for successful navigation. PMID:22912894

Auger, Stephen D.; Mullally, Sinead L.; Maguire, Eleanor A.

2012-01-01

452

Drive systems with permanent magnet synchronous motors  

SciTech Connect

This article reports that simulations indicate that a 15% longer electric-vehicle driving range is possible with permanent magnet synchronous motor drive systems compared with asynchronous types. The simplified driveline made possible by a permanent magnet design more than offsets its extra cost. A number of electric-motor types are suitable for electric-vehicle drive systems, one being the permanent magnet (PM) motor. The available of powerful PM materials, the choice of a high number of poles, and the possibility of field weakening are all essential factors for high-performance PM motors. Except for the magnets, PM motor designs are similar to other types of ac motors, and can use the same inverters as other ac motors. Tests and simulations of vehicle drive cycles have indicated that a substantially greater driving range is possible when PM motor drive systems are used. Due to the magnets, the cost of such systems is somewhat higher, but this can be compensated for by improved performance and simplified installation.

Eriksson, S.

1995-02-01

453

Genetic diversity of bovine viral diarrhea viruses in commercial bovine serum batches of Chinese origin.  

PubMed

Bovine viral diarrhea virus (BVDV) is often detected in commercial bovine serum. BVDV genetic diversity was investigated in commercial bovine serum of Chinese origin. Twenty-two batches of bovine serum were obtained from 10 suppliers with different geographic origins in China, and 20 batches of bovine serum were positive by reverse-transcription polymerase chain reaction (RT-PCR) and sequencing. Phylogenetic reconstructions of partial 5'UTR sequences indicated that the samples examined in this work clustered within the BVDV type 1 and BVDV type 2 genotypes. Interestingly, 3 sample sequences clustered into CSFV. These results suggest a high genetic diversity in Chinese BVDV field isolates. This study will benefit epidemiological surveys of BVDV detected in China. PMID:25102030

Zhang, Shu-Qin; Tan, Bin; Guo, Li; Wang, Feng-Xue; Zhu, Hong-Wei; Wen, Yong-Jun; Cheng, Shipeng

2014-10-01

454

New Structural Parameters and Permanents of Adjacency Matrices of Fullerenes  

E-print Network

New Structural Parameters and Permanents of Adjacency Matrices of Fullerenes Shan Jiang Heng Liang.R.CHINA. (Received November 25, 2004) Abstract The permanent of the adjacency matrix of a fullerene Cn is related. The stepwise regression model is used to predict the permanents of adjacency matrices of fullerenes

Bai, Fengshan

455

Starting and synchronization of permanent magnet hysteresis motors  

Microsoft Academic Search

This paper presents the design and application of permanent magnets in hysteresis motors with a view to improve the overall performances of such motors. The novel rotor consists of 36% cobalt steel alloys with neodymium boron iron permanent magnets. This hybrid design combines advantageous performance features of both typical permanent magnet motors and conventional hysteresis motors. Machine models for steady

M. A. Rahman; Ruifeng Qin

1994-01-01

456

Starting and synchronization of permanent magnet hysteresis motors  

Microsoft Academic Search

This paper presents the design, analysis, and application of permanent magnets in a hysteresis motor with a view to improve the overall performance of such motors. The novel rotor consists of 36% cobalt steel alloys with neodymium boron iron permanent magnets. This hybrid design combines the advantageous performance features of both typical permanent magnet motors and conventional hysteresis motors. The

M. Azizur Rahman; Ruifeng Qin

1996-01-01

457

A novel permanent magnet motor with doubly salient structure  

Microsoft Academic Search

A new type of doubly salient machine is presented in which the field excitation is provided by nonrotating permanent magnets. This doubly salient permanent magnet (DSPM) motor is shown to be kindred to square waveform permanent magnet brushless DC motors. Linear and nonlinear analyses are made to investigate the characteristics of this new type of PM motor. A prototype DSPM

Yuefeng Liao; Feng Liang; Thomas A. Lipo

1995-01-01

458

Replacement of Missing Anterior Teeth in a Patient with Chronic Mouth Breathing and Tongue Thrusting  

PubMed Central

The loss of anterior teeth has serious functional, esthetic disabilities, in addition to compromising the patients' quality of life. Various etiologies can be attributed to the anterior tooth loss, including trauma, caries, and periodontal diseases. The chronic mouth breathing due to nasal adenoids is known to enhance the gingival and periodontal diseases. The dental literature proves the association of nasal breathing, tongue thrusting, and anterior open bite. Arch shape and tooth position are primarily determined by the equilibrium of the forces from tongue and perioral musculature. Increased force from tongue musculature in the tongue thrusting patient leads to flaring of anterior teeth, making them susceptible for periodontal and traumatic tooth loss. Replacement of the anterior teeth in this patient will also help in restoration of anterior guidance, which is critical for the health of temporomandibular joint, posterior teeth, and musculature. PMID:24490091

Haralur, Satheesh B.; Al-Qahtani, Ali Saad

2013-01-01

459

Teeth segmentation of dental periapical radiographs based on local singularity analysis.  

PubMed

Teeth segmentation for periapical raidographs is one of the most critical tasks for effective periapical lesion or periodontitis detection, as both types of anomalies usually occur around tooth boundaries and dental radiographs are often subject to noise, low contrast, and uneven illumination. In this paper, we propose an effective scheme to segment each tooth in periapical radiographs. The method consists of four stages: image enhancement using adaptive power law transformation, local singularity analysis using Hölder exponent, tooth recognition using Otsu's thresholding and connected component analysis, and tooth delineation using snake boundary tracking and morphological operations. Experimental results of 28 periapical radiographs containing 106 teeth in total and 75 useful for dental examination demonstrate that 105 teeth are successfully isolated and segmented, and the overall mean segmentation accuracy of all 75 useful teeth in terms of (TP, FP) is (0.8959, 0.0093) with standard deviation (0.0737, 0.0096), respectively. PMID:24252317

Lin, P L; Huang, P Y; Huang, P W; Hsu, H C; Chen, C C

2014-02-01

460

Restoration of anterior teeth using an indirect composite technique. Case report  

PubMed Central

SUMMARY Objective. This article presents a case report of restoration of anterior teeth using an indirect technique with composite veneers in order to restore the dental anatomy and to provide aesthetic and function of anterior teeth. Materials and methods. A treatment of upper anterior teeth with indirect micro-hybrid composite restoration was proposed to a 40-year-old woman with old discolored and fractured ceramic veneers. Upper six anterior teeth were prepared and, after impressions with VPS of maxillary arche, the composite veneers were placed. Discussion and results. There are several advantages offered by indirect techniques compared to direct techniques. The increased practice of veneering technique with indirect composites is due to improvement in the properties of composite materials in the last years. The results are very favourable and the patient is satisfied. Conclusions. The restorations with composite veneers have proved durable and aesthetic, protect tooth structure and aesthetic and function is predictably re-established. PMID:24971164

GARGARI, M.; CERUSO, F.M.; PUJIA, A.; PRETE, V.

2013-01-01

461

Survival time of endodontically treated teeth: a 7-year retrospective clinical study  

NASA Astrophysics Data System (ADS)

The aim of this retrospective clinical study was to examine the survival time of endodontically treated teeth (ETT) and the factors that may influence the failure risk, over a period of up to 7 years. The files of 67 patients that received metal free post and core restorations using a standardized technique were analyzed. The survival probability was assessed using Kaplan-Meyer analysis and Log Rank (Matel-Cox). Cox regression was used to assess the risk of failure and to identify possible covariates. The average survival time of the ETT was 6.6 Years. The cumulative failure rate was 5.82% for all type of the restored endodontically treated teeth. The main failure type was encountered in the cervical area of the teeth, and due to the extensive hard tissue loss, the teeth were extracted.

Baldea, Bogdan; Canjau, Silvana; Popescu, Dragos; Tudor, Anca; Todea, Carmen

2014-01-01

462

Fluorine Content of Microsaur Teeth from the Carboniferous Rocks of Joggins, Nova Scotia  

Microsoft Academic Search

Because the Carboniferous deposits at Joggins, Nova Scotia, contain the earliest fauna of terrestrial vertebrates, the extremely well-preserved teeth of these ancient animals are of special interest. The \\

John S. Stevenson; Louise S. Stevenson

1966-01-01

463

Multivariate Analyses of Small Theropod Dinosaur Teeth and Implications for Paleoecological Turnover through Time  

PubMed Central

Isolated small theropod teeth are abundant in vertebrate microfossil assemblages, and are frequently used in studies of species diversity in ancient ecosystems. However, determining the taxonomic affinities of these teeth is problematic due to an absence of associated diagnostic skeletal material. Species such as Dromaeosaurus albertensis, Richardoestesia gilmorei, and Saurornitholestes langstoni are known from skeletal remains that have been recovered exclusively from the Dinosaur Park Formation (Campanian). It is therefore likely that teeth from different formations widely disparate in age or geographic position are not referable to these species. Tooth taxa without any associated skeletal material, such as Paronychodon lacustris and Richardoestesia isosceles, have also been identified from multiple localities of disparate ages throughout the Late Cretaceous. To address this problem, a dataset of measurements of 1183 small theropod teeth (the most specimen-rich theropod tooth dataset ever constructed) from North America ranging in age from Santonian through Maastrichtian were analyzed using multivariate statistical methods: canonical variate analysis, pairwise discriminant function analysis, and multivariate analysis of variance. The results indicate that teeth referred to the same taxon from different formations are often quantitatively distinct. In contrast, isolated teeth found in time equivalent formations are not quantitatively distinguishable from each other. These results support the hypothesis that small theropod taxa, like other dinosaurs in the Late Cretaceous, tend to be exclusive to discrete host formations. The methods outlined have great potential for future studies of isolated teeth worldwide, and may be the most useful non-destructive technique known of extracting the most data possible from isolated and fragmentary specimens. The ability to accurately assess species diversity and turnover through time based on isolated teeth will help illuminate patterns of evolution and extinction in these groups and potentially others in greater detail than has previously been thought possible without more complete skeletal material. PMID:23372708

Larson, Derek W.; Currie, Philip J.

2013-01-01

464

Propolis as storage media for avulsed teeth: microscopic and morphometric analysis in rats.  

PubMed

The maintenance of the avulsed teeth in appropriate media for preserving the cellular viability has been important for repairing the periodontal ligament and preventing the root resorption after tooth reimplantation. Propolis is a substance capable of preserving cellular viability. This study aimed to analyze the propolis substance as a storage media for maintaining the avulsed teeth, besides to determine the ideal time period for keeping the tooth inside it. Thus, 60 maxillary right central incisors of rats were extracted and divided into five groups. In groups I and II, teeth were kept in propolis for 60 min and 6 h, respectively; in group III, teeth were kept in milk for 6 h; in group IV, teeth were kept dry for 60 min; and in group V, they were immediately reimplanted. All teeth had their root canals filled with calcium hydroxide paste. Following, teeth were reimplanted in their sockets. After 15 and 60 days, animals were killed and the obtained samples were processed in laboratory for microscopic and morphometric analyzing. The results showed that the occurrence of inflammatory resorption, dental ankylosis and the formation of the connective tissue parallel to the root surface were similar among groups. It could be verified a greater occurrence of replacement resorption in group IV when comparing to other groups. In groups I and IV, the presence of periodontal ligament-like connective tissue was substantially smaller than the other groups. Regarding to the cementum amount over the root, it could be observed that this was present in smaller amount in groups I and IV. Group II was similar to groups III and IV. Therefore, according to the results of this study, the use of propolis as a storage media for maintaining avulsed teeth could be highlighted, and the 6-h period was more appropriate than the 60-min period. PMID:20089064

Mori, Graziela Garrido; Nunes, Daniele Clapes; Castilho, Lithiene Ribeiro; de Moraes, Ivaldo Gomes; Poi, Wilson Roberto

2010-02-01

465

Fracture Resistance of Teeth Restored with Direct and Indirect Composite Restorations  

PubMed Central

Objective: Tooth fracture is a common dental problem. By extension of cavity dimensions, the remaining tooth structure weakens and occlusal forces may cause tooth fracture. The aim of this study was to evaluate and compare the fracture resistance of teeth restored with direct and indirect composite restorations. Materials and Methods: Sixty-five sound maxillary premolar teeth were chosen and randomly divided into five groups each comprising thirteen. Fifty-two teeth received mesio-occluso-distal (MOD) cavities with 4.5mm bucco-lingual width, 4mm pulpal depth and 3mm gingival depth and were divided into the following four groups. G-1: restored with direct composite (Z-250, 3M/ESPE) with cusp coverage, G-2: restored with direct composite (Z-250) without cusp coverage, G-3: restored with direct composite (Gradia, GC-international) with cusp coverage, G-4: restored with indirect composite (Gradia, GC-International) with cusp coverage. Intact teeth were used in G-5 as control. The teeth were subjected to a compressive axial loading using a 4 mm diameter rod in a universal testing machine with 1 mm/min speed. Data were analyzed using one-way ANOVA and Tukey tests. Results: The mean fracture strength recorded was: G-1: 1148.46N±262, G-2: 791.54N±235, G-3: 880.00N±123, G-4: 800.00N±187, G-5: 1051.54N±345. ANOVA revealed significant differences between groups (p<0.05). Tukey test showed significant difference between group 1 and the other groups. There was no significant difference among other groups. Conclusion: Direct composite (Z-250) with cusp coverage is a desirable treatment for weakened teeth. Treatment with Z-250 without cusp coverage, direct and indirect Gradia with cusp coverage restored the strength of the teeth to the level of intact teeth. PMID:24910649

Torabzadeh, Hassan; Ghasemi, Amir; Dabestani, Atoosa; Razmavar, Sara

2013-01-01

466

CADMIUM AND LEAD LEVELS IN DECIDUOUS TEETH OF CHILDREN LIVING IN MÉXICO CITY  

Microsoft Academic Search

Cadmium and lead levels in 79 deciduous teeth from children between 5 and 13 years old living in the México City Metropolitan Zone were determined by graphite furnace atomic absorption spectrometry. Lead and cadmium concentrations showed a positively skewed distribution and results were transformed into logarithms. The geometric mean concentrations (GM) in all teeth were 0.22 ± 3.4 and 10.2

Armando BÁEZ; Raúl BELMONT; Rocío GARCÍA; Juan Carlos HERNÁNDEZ

2004-01-01

467

Bond Strength and Interfacial Morphology of Different Dentin Adhesives in Primary Teeth  

PubMed Central

Objective: To evaluate the interfacial morphology and the bond strength produced by the three-step, two-step and single-step bonding systems in primary teeth. Materials and Methods: Occlusal surfaces of 72 extracted human deciduous teeth were ground to expose the dentin. The teeth were divided into four groups: (a) Scotchbond Multipurpose (3M, ESPE), (b) Adh Se (Vivadent), (d) OptiBond All-in-One (Kerr) and (e)Futurabond NR (VOCO, Cuxhaven, Germany). The adhesives were applied to each group following the manufacturer’s instructions. Then, teeth from each group were divided into two groups: (A) For viewing interfacial morphology (32 teeth), with 8 teeth in each group, and (B) For measurement of bond strength (40 teeth), with 10 teeth in each group. All the samples were prepared for viewing under SEM. The statistical analysis was done using SPSS version 15.0 software. Results: Observational measurement of tag length in different adhesives revealed that Scotchbond had the most widely spread values with a range from 12.20 to 89.10?m while OptiBond AIO had the narrowest range (0 to 22.50). The bond strength of Scotchbond Multipurpose was significantly higher (7.4744±1.88763) (p<0.001) as compared to Futurabond NR (3.8070±1.61345), Adhe SE (4.4478 ± 1.3820) and OptiBond-all-in-one (4.4856±1.07925). Conclusion: The three-step bonding system showed better results as compared to simplified studied bonding systems PMID:24910694

Vashisth, Pallavi; Mittal, Mudit; Goswami, Mousumi; Chaudhary, Seema; Dwivedi, Swati

2014-01-01

468

Effects of orthodontic load on the periodontium of autogenously transplanted teeth in beagle dogs*  

PubMed Central

Objective: To observe the periodontal healing of autogenously transplanted teeth loaded orthodontically after autotransplantation in Beagle dogs. Methods: Forty-eight teeth were autogenously transplanted, 24 of which were loaded postoperatively with orthodontic force at different time points and for different durations. Periodontal healing was evaluated by probing pocket depth (PPD), the expression of relevant proteins, and histomorphometric analyses. Results: The dental pockets of loaded and non-loaded teeth were both much deeper after the first postoperative week than before transplantation (P<0.05). Later, the PPD, which was measured after postoperative weeks 1, 3, 5, 9 and 13, gradually became shallow. The expressions of alkaline phosphatase (ALP) and basic fibroblast growth factor (bFGF) were higher in loaded teeth than in non-loaded teeth (P<0.05), and in groups subjected to two weeks duration of loading than in other groups at the same load time point (P<0.05). For the same load duration, the expressions of ALP and bFGF in teeth loaded after postoperative week 4 were higher than those of other treatments (P<0.05). According to histomorphometric analyses, an orthodontic force on transplanted teeth applied after postoperative weeks 4 or 8 for two weeks duration should be favorable for periodontal healing. Conclusions: It is advisable to apply an appropriate magnitude of force on autotransplanted teeth, such as orthodontic force, at appropriate time points and for a suitable duration, to achieve the optimal clinical prognosis following autogenous tooth transplantation. These results may serve as a basis for subsequent studies in humans so as to make clinical improvements. PMID:24190448

Lu, Lu; Sun, Hui-fang; Xue, Han; Guo, Jing; Chen, Yang-xi

2013-01-01

469

In situ Raman spectroscopic studies of the teeth of the chiton Acanthopleura hirtosa  

Microsoft Academic Search

In situ Raman spectroscopy, in combination with energy dispersive spectroscopy, has been used for the first time to determine\\u000a the identities and locations, at the micron level, of mineral phases present in single chiton teeth that have been extensively\\u000a mineralized. At the later stages of development the major lateral teeth of the chiton Acanthopleura hirtosa show characteristic spectroscopic evidence for

Alasdair P. Lee; John Webb; D. J. Macey; Wilhelm van Bronswijk; Angela R. Savarese; G. Charmaine de Witt

1998-01-01

470

Fracture resistance of endodontically treated teeth restored with bonded amalgam and full crowns.  

PubMed

The use of dentin bonding prior to placement of core build-up restorations has been shown to reduce microleakage and reinforce remaining tooth structure. However, information is lacking about the influence a core build-up has on the fracture resistance of crowned teeth. The purpose of this in-vitro study was to compare the influence of three types of core build-ups on the fracture resistance of crowned teeth. PMID:10687470

Barkhordar, R A; Plesh, O; Curtis, D A; Watanabe, L; Parisi, R G

1999-01-01

471

Assessment of structural changes of human teeth by low-field nuclear magnetic resonance (NMR)  

NASA Astrophysics Data System (ADS)

A technique of low-field pulsed proton nuclear magnetic resonance (NMR) spin relaxation is described for assessment of age-related structural changes (dentin and pulp) of human teeth in vitro. The technique involves spin-spin relaxation measurement and inversion spin-spin spectral analysis methods. The spin-spin relaxation decay curve is converted into a T2 distribution spectrum by a sum of single exponential decays. The NMR spectra from the extracted dentin-portion-only and dental pulp-cells-only were compared with the whole extracted teeth spectra, for the dentin and pulp peak assignments. While dentin and pulp are highly significant parameters in determining tooth quality, variations in these parameters with age can be used as an effective tool for estimating tooth quality. Here we propose an NMR calibration method—the ratio of the amount of dentin to the amount of pulp obtained from NMR T2 distribution spectra can be used for measuring the age-related structural changes in teeth while eliminating any variations in size of teeth. Eight teeth (third molars) extracted from humans, aged among 17-67 years old, were tested in this study. It is found that the intensity ratio of dentin to pulp sensitively changes from 0.48 to 3.2 approaching a linear growth with age. This indicates that age-related structural changes in human teeth can be detected using the low-field NMR technique.

Ni, Qingwen; Chen, Shuo

2010-01-01

472

9 CFR 113.68 - Pasteurella Haemolytica Vaccine, Bovine.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Pasteurella Haemolytica Vaccine, Bovine. 113.68 Section 113.68...VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.68 Pasteurella Haemolytica Vaccine, Bovine. Pasteurella Haemolytica...

2010-01-01

473

9 CFR 113.68 - Pasteurella Haemolytica Vaccine, Bovine.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Pasteurella Haemolytica Vaccine, Bovine. 113.68 Section 113.68...VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.68 Pasteurella Haemolytica Vaccine, Bovine. Pasteurella Haemolytica...

2011-01-01

474

9 CFR 113.69 - Pasteurella Multocida Vaccine, Bovine.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Pasteurella Multocida Vaccine, Bovine. 113.69 Section 113.69...VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.69 Pasteurella Multocida Vaccine, Bovine. Pasteurella Multocida...

2011-01-01

475

9 CFR 113.69 - Pasteurella Multocida Vaccine, Bovine.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Pasteurella Multocida Vaccine, Bovine. 113.69 Section 113.69...VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.69 Pasteurella Multocida Vaccine, Bovine. Pasteurella Multocida...

2010-01-01

476

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Bovine Virus Diarrhea Vaccine. 113.311 Section...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.311 Bovine...

2013-01-01

477

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Bovine Virus Diarrhea Vaccine. 113.311 Section...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.311 Bovine...

2012-01-01

478

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Bovine Virus Diarrhea Vaccine. 113.311 Section...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.311 Bovine...

2011-01-01

479

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

...2014-01-01 2014-01-01 false Bovine Virus Diarrhea Vaccine. 113.311 Section...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.311 Bovine...

2014-01-01

480

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Bovine Virus Diarrhea Vaccine. 113.311 Section...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.311 Bovine...

2010-01-01

481

Recent Progress in Cryopreservation of Bovine Oocytes  

PubMed Central

Principle of oocyte cryoinjury is first overviewed and then research history of cryopreservation using bovine oocytes is summarized for the last two decades with a few special references to recent progresses. Various types of cryodevices have been developed to accelerate the cooling rate and applied to the oocytes from large domestic species enriched with cytoplasmic lipid droplets. Two recent approaches include the qualitative improvement of IVM oocytes prior to the vitrification and the short-term recovery culture of vitrified-warmed oocytes prior to the subsequent IVF. Supplementation of L-carnitine to IVM medium of bovine oocytes has been reported to reduce the amount of cytoplasmic lipid droplets and improve the cryotolerance of the oocytes, but it is still controversial whether the positive effect of L-carnitine is reproducible. Incidence of multiple aster formation, a possible cause for low developmental potential of vitrified-warmed bovine oocytes, was inhibited by a short-term culture of the postwarm oocytes in the presence of Rho-associated coiled-coil kinase (ROCK) inhibitor. Use of an antioxidant ?-tocopherol, instead of the ROCK inhibitor, also supported the revivability of the postwarm bovine oocytes. Further improvements of the vitrification procedure, combined with pre- and postvitrification chemical treatment, would overcome the high sensitivity of bovine oocytes to cryopreservation. PMID:24738063

Hochi, Shinichi

2014-01-01

482

The p66Shc Adaptor Protein Controls Oxidative Stress Response in Early Bovine Embryos  

PubMed Central

The in vitro production of mammalian embryos suffers from high frequencies of developmental failure due to excessive levels of permanent embryo arrest and apoptosis caused by oxidative stress. The p66Shc stress adaptor protein controls oxidative stress response of somatic cells by regulating intracellular ROS levels through multiple pathways, including mitochondrial ROS generation and the repression of antioxidant gene expression. We have previously demonstrated a strong relationship with elevated p66Shc levels, reduced antioxidant levels and greater intracellular ROS generation with the high incidence of permanent cell cycle arrest of 2–4 cell embryos cultured under high oxygen tensions or after oxidant treatment. The main objective of this study was to establish a functional role for p66Shc in regulating the oxidative stress response during early embryo development. Using RNA interference in bovine zygotes we show that p66Shc knockdown embryos exhibited increased MnSOD levels, reduced intracellular ROS and DNA damage that resulted in a greater propensity for development to the blastocyst stage. P66Shc knockdown embryos were stress resistant exhibiting significantly reduced intracellular ROS levels, DNA damage, permanent 2–4 cell embryo arrest and diminished apoptosis frequencies after oxidant treatment. The results of this study demonstrate that p66Shc controls the oxidative stress response in early mammalian embryos. Small molecule inhibition of p66Shc may be a viable clinical therapy to increase the developmental potential of in vitro produced mammalian embryos. PMID:24475205

Betts, Dean H.; Bain, Nathan T.; Madan, Pavneesh

2014-01-01

483

Review of the success of pulp exposure treatment of cariously and traumatically exposed pulps in immature permanent incisors and molars.  

PubMed

The decision to retain immature permanent tooth with pulp disease is problematical. Restoring the tooth would normally involve some form of pulp capping/pulpotomy procedure or a more radical pulpectomy and root canal treatment. Pulp capping/pulpotomy procedures, where all or part of the pulp is retained, relies upon an accurate assessment of the pulp condition, and the careful management of the remaining healthy tissue. Pulpectomy or root canal treatment is technically difficult as the root apex is open with the result that conventional preparation and filling techniques are compromised. On the other hand, the inappropriate extraction of immature teeth with pulp disease will result in immediate aesthetic and functional difficulties that may require the patient to have orthodontic or restorative care that will have potential life-long implications, e. g. removable or fixed prosthesis. The aim of this article is to provide an overview of the aetiology of pulp disease in immature teeth and to review current evidence of the outcome of conservative pulp treatment. PMID:23128488

Gudkina, Jekaterina; Mindere, Anda; Locane, Gundega; Brinkmane, Anda

2012-01-01