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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Prevalência do lado preferencial mastigatório e sua relação com a alimentação, a saúde periodontal, o lado preferencial no primeiro ciclo mastigatório e a dominância lateral nas dentições decídua, mista e permanente /

Barcellos, Daphne Camara. January 2010 (has links)
Resumo: Esse estudo de prevalência objetivou avaliar o lado preferencial mastigatório nas dentições decídua, mista e permanente e sua relação com: a consistência da dieta alimentar; o índice de placa e o índice gengival entre as hemi-arcadas direita e esquerda; o lado preferencial no primeiro ciclo mastigatório e as dominâncias laterais. Foram avaliados 300 indivíduos divididos em três grupos: Grupo 1 - 100 indivíduos entre 3 e 5 anos de idade com dentição decídua; Grupo 2 - 100 indivíduos entre 6 e 12 anos de idade com dentição mista; Grupo 3 - 100 indivíduos a partir de 18 anos de idade com dentição permanente. Foram coletados dados sobre a consistência alimentar (sólido, semi-sólido, pastoso e líquido) dos indivíduos. Foi realizado o índice gengival segundo o critério de Löe e Silness (1963) e o índice de placa segundo os critérios de Greene e Vermilion (1964) entre as hemi-arcadas direitas e esquerdas. Foi realizado o teste midificado de Mc Donnell et al. (2004) para determinar o lado preferencial mastigatório e o teste desenvolvido por Hoogmartens e Caubergh (1987a) para determinar o lado preferencial no primeiro ciclo mastigatório. Foi realizado o teste desenvolvido por Porac e Coren (1981) para determinar a dominância lateral das mãos, pés, olhos e ouvidos. Foi utilizada estatística descritiva para observar a prevalência do lado preferencial mastigatório, o teste Qui-quadrado e o teste Z para a relação entre os dados obtidos. Pode-se observar uma prevalência do lado preferencial mastigatório de 87% para o grupo 1, de 82% para o grupo 2 e de 76% para o grupo 3. O teste qui-quadrado demonstrou haver relação significante entre o lado preferencial mastigatório e: o lado preferencial no 9 primeiro ciclo mastigatório para os grupos 1, 2 e 3; a dominância lateral dos ouvidos para o grupo 1; e as dominâncias laterais das mãos e dos pés para grupos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study evaluated the prevalence of chewing side preference in deciduous, mixed and permanent dentition and its relationship with: food consistency, gingival and plaque index between the left and right hemiarcades, the side preference at first chewing and lateral dominance. It was evaluated 300 subjects divided into three groups: Group 1 - 100 individuals between 3 and 5 years old with deciduous dentition; Group 2 - 100 individuals between 6 and 12 years old with mixed dentition; 3 - 100 individuals between 18 and 47 years old with permanent dentition. Data of food consistency were obtained with a questionnaire (solid, semi-solid, paste and liquid). The plaque index was performed according to Greene and Vermilion (1964) criteria and the gingival index was performed according to Löe e Silness (1963) criteria, for the left and right hemiarcades. To determine the chewing side preference, was used the test developed by Christensen and Radue (1985a). To determine the side preference at first chewing, was used the test developed by Hoogmartens and Caubergh (1987a). To determine the lateral dominance of the hands, feet, eyes and ears, was used the test developed by Porac and Coren (1981). Descriptive statistics was used to observe the prevalence of the chewing side preference. The chi-square test and Wilcoxon test and Z-test were used for the relation between the data obtained. It can be observe the prevalence of the chewing side preference: 87% for group 1, 82% for group 2 and 76% for group 3. The chi-square test showed that there was significant relation between chewing side preference and: side preference at first chewing for the deciduous, mixed and permanent dentition; ear lateral dominance for the primary dentition; hand and feet lateral dominances for the mixed and permanent dentitions. It can be concluded that the side preference at first chewing is directly related to the chewing... (Complete abstract click electronic access below) / Orientador: Sérgio Eduardo de Paiva Gonçalves / Coorientador: César Rogério Pucci / Banca: Carlos Rocha Gomes Torres / Banca: Ricardo Amore / Mestre
112

The effect of preterm birth on the development of the dentition

Harila, V. (Virpi) 25 September 2004 (has links)
Abstract The aim of this study was to examine the effect of preterm birth on the development of the dentition. The spesific aims were to examine the effect on deciduous and permanent tooth crown dimensions, the eruption of permanent teeth and the sagittal occlusal relationships within the dentition. The subjects consisted of 328 prematurely born (< 37 gestational weeks ) white and black children and 1804 control children, who participated in the cross-sectional study of the Collaborative Perinatal Project (USA) in the 1960's and 1970's. Dental examinations, including dental casts were performed at the age of 6–12 years. Tooth crown size measurements, recording of the sagittal occlusal relationships and tooth eruption stages were performed by examining the dental casts. In general larger permanent tooth crown dimensions were found in preterm white boys and black girls and smaller permanent tooth crown dimensions in preterm white girls and black boys. There were both increased and decreased deciduous tooth crown dimensions in preterm children compared to controls, but no significant differences were found. Boys had larger tooth crown sizes than girls within all preterm and control groups showing sexual dimorphism. The results showed earlier eruption of permanent incisors and first molars in all preterm children compared to controls and also according to sex and race. Concerning the sagittal occlusal relationships, the results showed greater prevalence of prenormal canine relationships in preterm group than in the controls. When the molar relationships were concerned, the prevalence of mesial molar occlusion was greater in the preterm group. The incidence of bilateral symmetrical canine relationship was the same in both preterm and control groups, but inside the preterm group the girls had better symmetry than the boys. The findings of this research suggest that short gestation is not associated with reduced permanent and deciduous tooth crown dimensions in prematurely born children and also confirm the presence of the sexual dimorphism in tooth crown size. The studies also indicate that the clinical tooth eruption is accelerated in all observable permanent teeth in prematurely born children. The findings of occlusal morphology indicated that premature birth may effect the sagittal occlusal development. General health condition, neonatal and postnatal factors like intubation, postnatal molding of head shape and the importance of catch-up growth and early functional activity should be considered as possible influencing factors. Preterm birth may also interfere with the development of symmetry and lateralization.
113

Comparative Study of Dentition Among Species of Poecilia (Pisces)

Lewis, Steven R., Rasch, Ellen M., Hossler, Fred E., Kalbfleisch, John H., Monaco, Paul J. 01 January 1999 (has links)
Many studies in the genus Poecilia have focused on reproductive and genetic characteristics of Poecilia formosa, the Amazon molly, and its sympatric species P. latipinna and P. mexicana. The research literature of Poecilia dentition has been limited to general tooth morphology. Essentially absent are comparative analyses of dentition patterns and total numbers of teeth. The current study uses dentition analysis as a method to compare species in the genus Poecilia and to address some taxonomic issues related to these fish. The study focused on fish from the areas of southern Texas and northeastern Mexico. Through the use of scanning electron microscopy, the lower jaws of Poecilia spp were examined to determine total numbers of outer and inner teeth. In addition, the differences in distribution patterns of the inner teeth were recorded and compared. Statistical analyses were performed to determine which comparisons were significant. This study reveals several observations: 1) variations in the numbers of outer and inner teeth exist in some of these fish with respect to site of collection; 2) differences in total teeth numbers and dentition patterns were found both interspecifically and intraspecifically; and 3) in addition, dentition analysis provided evidence regarding the origin of P. formosa. This study supports the current notion that P. latipinna, the proported paternal component, and P. mexicana limantouri, the purported maternal component, are the progenitor species of P. formosa. Two unresolved taxonomic questions were addressed through dentition analysis. First, the present study supports the exclusion of the triploid associate of P. formosa as a separate species from P. formosa. Second, this study shows a significant difference in the number of inner teeth and in dentition patterns between P. mexicana limantouri and P. mexicana mexicana. Such differences, in addition to previously known distinguishing characteristics, should prompt careful consideration of whether or not these taxa deserve specific status or retention of their current subspecific status.
114

Reconciling Phylogenetic and Morphological Trends in North American Mammuthus

Widga, Chris, Saunders, Jeff, Enk, Jacob 02 July 2017 (has links)
The morphology of mammoth upper third permanent molars (M3) is used to address regional- and continental-scale patterns in the structure of mammoth populations. Recent refinements to the understanding of Mammuthus phylogenetic diversity south of the Laurentide ice show extensive overlap between regional populations. We assess the underlying geographic structure in Mammuthus tooth morphology in light of these new genetic data. Comparison of regional trends in dental morphology show a single, morphologically variable, population of Mammuthus was present in North America during the Wisconsin glaciation. Within this population, there are no significant differences in degree of hypsodonty or molar shape however, there is a geographic pattern of lower enamel:dentin ratios in Mammuthus from the Channel Islands, West Coast, and Southwest/Mexico as measured by the number of molar lamellae and the standardized thickness of lamellae. These results contrast with historical perspectives of Mammuthus population structure suggesting at least four species of North American mammoths but are consistent with recent phylogeographic analyses of mitochondrial ancient DNA.
115

INVISALIGN FIRST: A QUALITATIVE STUDY ON THE PERCEIVED BENEFITS AND DRAWBACKS OF INVISALIGN FIRST AS A TREATMENT MODALITY FOR MIXED DENTITION PATIENTS

Walker, Erin, Chen, James 25 September 2020 (has links)
Given the recent implementation of Invisalign First for early interceptive orthodontic treatment, a limited number of orthodontists have had experience with this treatment modality and there currently are no published studies on the topic. The present study aims to use a qualitative survey to identify common themes in providers’ perceptions of Invisalign First as a new treatment option for early interceptive orthodontics. Twenty-three orthodontists in the private practice sector voluntarily participated in an open-ended survey via email. The results of the survey indicate the following common themes in regards to benefits of Invisalign First: fewer emergencies, patient comfort, patient experience, patient happiness, ability to correct multiple things at once, and arch development. Some of the commonly cited drawbacks of Invisalign First are the following: attachment bonding issues, poor retention, and cost. Overall, all participants except for two (of twenty three) will continue to offer Invisalign First in some capacity. Seventeen participants spoke favorably of the treatment modality and would recommend Invisalign First to other providers. The results of this study provide a framework from which a more robust survey can be constructed. The intent of the future study is to gather and synthesize orthodontists’ perceptions based on experience with Invisalign First in a way that readers can constructively evaluate the potential for this treatment modality in their orthodontic practices.
116

A new high-latitude Tylosaurus (Squamata, Mosasauridae) from Canada with unique dentition

Garvey, Samuel T. 09 June 2020 (has links)
No description available.
117

Removable Appliance Therapy for Interceptive Orthodontic Treatment

Gupta, Vikas, Chen, James 01 January 2021 (has links)
Introduction: Socioeconomically disadvantaged children have limited access to orthodontic services not only because of their families’ competing needs for limited resources, but also because of the limited availability of orthodontists in their communities and a shortage of orthodontists who are willing to treat patients enrolled in Medicaid. We will systematically explore the hypothesis that an early interceptive treatment protocol using removable appliances provides the same treatment outcome but better cost-effectiveness than a traditional fixed-appliance protocol. Methods: Interim data on a prospective study with patients being treated either in private practice with rational fixed Phase I orthodontic treatment (n=11) or in a community clinic with removable interceptive orthodontic treatment (n=10). Initial and post treatment study models were acquired along with pretreatment PAR and clinical photos. PAR and ICON scores were assessed on all initial and final casts. Cost effective analyses were performed comparing the two treatment groups as well as comparing the removable group to no treatment. Sensitivity analyses were performed to assess the robustness of our data while manipulating certain treatment outcome variables. Results: For the fixed group the average PAR score at T2 was 7.6 with a 68% reduction from T1 to T2, while the ICON average score was 16.2 with a 67% reduction. In the removable group the average PAR score at T2 was 13.4 with a lesser reduction from T1 to T2 than the fixed group at 48% (p=0.20), while the ICON average score was 25.3 with a significantly lower reduction of 39% when compare to the fixed group (p=0.037). Cost effectiveness analyses showed that the removable appliance treatment protocol was cost effective when compared to no treatment but not cost effective when compared to 3 the traditional fixed Phase I treatment using the studies measured probabilities of success. Conclusion: The removable appliance protocol used at the Fruitvale community clinic can effectively reduce the severity of malocclusions. However, in order for this treatment to be cost effective when compared to a traditional fixed Phase I protocol it needs to demonstrate consistent clinical results and minimize the probability of “No Improvement”.
118

First Skulls of Arctomeles dimolodontus (Mustelidae: Melinae) from the Gray Fossil Site (Early Pliocene, TN) Reveal Extreme Intraspecific Variation

Bruce, Charles 01 May 2023 (has links) (PDF)
Here, a morphological description of the extinct meline badger Arctomeles dimolodontus from the Gray Fossil Site (GFS), Tennessee is provided with comparison to extant Meles meles. Originally described solely on upper teeth of a single individual, the recovery of several crania and jaws provides a sample of at least five individuals, affording the largest known fossil sample in North America of the enigmatic Melinae. Examination of A. dimolodontus skull material reveals extreme intraspecific variation in previously identified diagnostic characters, highlighting the need for caution when identifying fossil taxa based on similarly fragmentary remains. Dental variation is likely a result of hypocarnivory, and dentition may have become more complex over time in response to diet. Based on cranial characters, A. dimolodontus appears to be sexually dimorphic, similarly to extant badgers. Arctomeles dimolodontus has a complex auditory region with large bullae compared to M. meles, suggesting relatively heightened auditory sensitivity.
119

Determination of the biological sex of juveniles based upon the odontometrics of the primary dentition

McCollough, Kendall 01 May 2012 (has links)
Sex determination in human skeletal remains is difficult under the most ideal circumstances; however, in juvenile skeletal remains it is nearly impossible. Currently no accepted techniques exist to identify the biological sex of the juvenile skeleton, other than, when possible, DNA. Thus, developing an accessible and non-destructive technique would benefit both the field of Forensic Anthropology and Bioarchaeology. The ability to provide a quick and accurate determination of sex would greatly expedite the identification process in any case where juvenile skeletal remains are involved. This project aims to establish an accessible and non-destructive method for determining the sex of juvenile skeletal remains using deciduous (primary/baby) dentition. This research is focused on the deciduous dentition as they form early during growth and development, and previous research has demonstrated that secondary (adult) dentition exhibit sexual dimorphism. Samples of known sex individuals (n= 12: 7 female, 5 male, 45 total teeth) have been collected by donation. Using a novel approach, physical and radiograph, measurements of overall tooth and internal structure dimensions were completed on all samples. Comparative statistical analyses are used to determine if significant sexual dimorphism exists. Results indicate that marked (4-10%) sexual dimorphism does exist in the overall size of deciduous dentition; however, it cannot be assumed that males are larger in all tooth structures. Results suggest that while males do have larger central incisors and canines, their lateral incisors have smaller measurements than females. The variance in tooth structure dimensions will allow the creation of methodology to determine the sex when the majority of dentition is present.
120

The Oral Microbiome of the Primary Dentition in Health and Disease: A Focus on Streptococcus mutans Strains and Caries

Spiritoso, Stephen, Spiritoso 02 November 2017 (has links)
No description available.

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