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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.
21

Hypoplastické defekty skloviny u Slovanů z raně středověkého pohřebiště Rajhrad. / Dental enamel hypoplasia in early medieval population of Rajhrad.

Zahradníková, Mariana January 2012 (has links)
The objective of this study was the assessment of linear enamel hypoplasia (LEH) in early medieval Great Moravian population sample - Rajhrad. Linear enamel hypoplasia represents the disruption of enamel matrix secretion during the growth of the tooth crown, which is related to a generalized growth disturbance. This is why it is considered as a nonspecific stress marker. The incidence of LEH could reflect stress factors during the life of early medieval population. The aim of this study was to asses the frequency and timing of the LEH. The incidence of LEH was supposed to be high because of poorer nature of this cemetery. The results of our study could confirm or falsify this assumption and determine relation between LEH and socio-economic status. The timing of LEH was estimated from regression equations consisting of distance from LEH to CEJ (cemento-enamel junction) and crown height of upper and lower canines. 108 individuals from approximately 4 - 15 years were observed. The frequency was high according to the assumption - 88 %. That confirms poorer life conditions. The range of mean age of LEH formation was from 2,94 - 4,72 years in individuals with multiple LEH incidence. The mean age of single LEH formation was approximately 3,98 years. The earliest onset of LEH in the pooled sample occurred...
22

Early life histories : a study of past childhood diet and health using stable isotopes and enamel hypoplasia

Henderson, Rowena Claire January 2015 (has links)
The &delta;&delta;<sup>13</sup>C and &delta;<sup>15</sup>N composition of incremental segments of tooth dentine was used to infer infant and childhood diet in a post-medieval London population, and a hunting and gathering Mesolithic/Neolithic group from Latvia. Health was analysed using defects on the tooth enamel caused by stress, termed enamel hypoplasia. The populations, which differ markedly in their economy, diet and health, were selected because of the difference in childhood experiences between the two groups. The results were used to consider questions about childhood, including how early diet may have been influenced by social factors such as class or status, the effect this could have on population dynamics and how childhood diet and health are related. The results show that the London individuals were rarely breastfed beyond 6 months and in some instances not at all. A small isotopic difference between males and females was observed which could be caused by dietary or physiological differences. The peak incidence of hypoplasia may be related to developmental patterns, rather than stress caused by weaning. The Zvejnieki individuals had a slightly longer breastfeeding duration. Those buried with pendants consumed a different diet in childhood to those without pendants, suggesting a complex social system, possibly indicating that diet was related to the role a person had within the community. There is a suggestion diet may have shifted between the Middle Mesolithic and Late Neolithic, although not dramatically. Neither population have elevated &delta;<sup>13</sup>C often associated with breastfeeding. The early life histories of the groups are not compared directly, but general observations concerning the children’s lives are considered. It is concluded that economy is not a reliable predictor of infant feeding strategies, as hunter-gatherers provide children with solid foods at a similar time to industrial groups. Intra-population variability was found to be a feature of all socio-economic groups.
23

Avaliação do traumatismo em dente decíduo e da seqüela no dente permanente sucessor /

Assunção, Luciana Reichert da Silva. January 2005 (has links)
Resumo: Estudos mostram que os traumatismos na dentição decídua são comuns, podendo trazer também comprometimentos aos dentes permanentes em desenvolvimento. O propósito desta pesquisa foi avaliar os traumatismos em dentes decíduos e as seqüelas nos dentes permanentes sucessores, em crianças atendidas no Pronto Atendimento da Bebê Clínica, da Universidade Estadual de Londrina, entre os anos de 1992 a 2002. Da análise de 1703 prontuários que apresentavam relato de traumatismos nos dentes decíduos, 864 atenderam os critérios de inclusão propostos para este estudo, sendo que 409 crianças foram localizadas e compareceram ao local de exame. Os prontuários destas crianças foram estudados a fim de se obter informações a respeito do trauma. O exame clínico e radiográfico foi realizado com o objetivo de verificar as seqüelas nos dentes permanentes em decorrência dos traumatismos nos antecessores decíduos. Para a análise destas seqüelas, a amostra foi dividida em 2 grupos, sendo o Grupo I constituindo as crianças com apenas uma ocorrência de traumatismo nos dentes decíduos e o Grupo II, aquelas com mais de uma ocorrência. A freqüência de injúrias traumáticas nos dentes decíduos foi de 31,9% no total dos 1703 prontuários avaliados. Das crianças examinadas, o gênero masculino foi o mais acometido (57%) e a idade da criança no momento do trauma entre 6 e 24 meses, a mais observada (38,4%). As quedas de uma forma geral, e entre estas, aquelas causadas pelo andar e correr foram os fatores etiológicos mais predominantes (37,8%). O tempo decorrido entre o trauma e a procura por atendimento foi mais averiguado no periodo de até 1 dia (43,5%). Dos 679 dentes decíduos avaliados, o incisivo central superior direito foi o mais afetado (42,0%) e a subluxação, o tipo de traumatismo mais prevalente ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Studies show dental trauma in primary teeth as common happening and the risk of compromising the permanent teeth in developing process. The purpose of this research was to evaluate the dental trauma in primary teeth and its sequelae in the successor permanent teeth in children attended at Pronto Atendimento da Bebê Clínica, State University of Londrina, from 1992 to 2002. From the analysis of 1703 children presenting cases of dental trauma in primary teeth, 864 attended the criteria of inclusion proposed to this study. From the total above 409 children were located and came to the examine place. The data of these children were studied in order to obtain precise information regarding trauma. The clinical and radiographic exams were carried out with the objective to verify sequelae in the permanent teeth due to traumas caused on the predecessor deciduous. For the analysis of these sequelae the sample was divided into 2 groups: Group I, consist of children with only one occurrence of trauma in the primary teeth and group II, of those with more occurrences. The frequency of traumatic injuries in the deciduous teeth was 31,9% in total of the 1703 cases evaluated. From the examined children, masculine gender was the most compromised (57%) and the age of the child in the moment of the trauma was between 6 and 24 moths (38,4%). Falls in general, among those caused by walking and runnings were the etiologic predominant factors (37,8%). The time between trauma and seeing the dentist was done in a period of a day (43,5%). From 679 deciduous teeth evaluated, the right maxillary central incisor was the most affected (42,0%) and the subluxation, type of trauma more frequent (32,5%). In regard to the treatment recommended to the primary teeth monitoring was the most used ...( Complete abstract click electronic address below) / Orientador: Robson Frederico Cunha / Coorientador: Antônio Ferelle / Banca: Farli Aparecida Carrilho Boer / Banca: Célio Percinoto / Banca: Robson Frederico Cunha / Mestre
24

An odontological study of ovicaprine herding strategies in the North Atlantic islands : the potential of dental enamel defects for identifying secondary product utilisation in an archaeological context

Ewens, Vicky Jane January 2010 (has links)
Recent debate concerning the suitability of mortality profile analysis for identifying secondary product utilisation within archaeozoological assemblages has prompted the search for alternative methodologies. This research explores the potential of using weaning age to provide insight into herding strategies in ovicaprines, determined through the prevalence of developmental enamel defects. A histological methodology was developed, adapted to the specific nature of sheep molars through an understanding of formation processes and enamel structures. This established a relationship between weaning and developmental defects in modern sheep, revealed as distinct patterns in defect distribution within the enamel. Based on historical/archaeological data a weaning age model was developed for the North Atlantic region by which herding strategies could be recognised, specifically: mixed milk/meat subsistence, with an emphasis on milk (0-2 months) or on meat (2-4 months), and the optimisation of meat and/or wool (4-6 months). This methodology was then tested on archaeological material to interpret husbandry at Iron Age and Norse/Viking period sites. The results of this analysis showed that interpretations were in general agreement with those of mortality profile and correspondence analysis conducted as a methodological comparative. Some disparity, however, highlighted the ability of this new technique to provide more sensitivity in cases of mixed subsistence systems, possibly identifying the economic focus of husbandry, or where mortality profiles are confused. It was concluded that the study of weaning age has potential to provide valuable insight into ovicaprine husbandry in archaeological contexts, adding to the understanding of faunal assemblages, especially when supported with other evidence.
25

Hunter-Gatherers of the Central Gulf Coastal Plain and the Lower Pecos Region of Texas: Interpreting Patterns of Health and Variability

Jones, Christine 03 October 2013 (has links)
This dissertation explores patterns of health and variability among hunter-gatherers during the Holocene in two distinct ecological settings: the semi-arid Lower Pecos and Central Western Gulf Coastal Plain regions of Texas. Skeletal indicators of long-term and short-term stress were examined for 279 individuals representing 20 cemetery sites. To test the assumption that stress indicators, and therefore interpretations of health, for hunter-gatherers are not homogenous but extremely variable, patterning in age, sex, porotic hyperostosis, cribra orbitalia, linear enamel hypoplasia and periostitis are analyzed. There are no significant differences in the frequencies of cribra orbitalia for adults by region; a significantly greater proportion of subadults in the Coastal Plain region were affected with anemia in infancy (40%) than adults (13.8%). If severity is not taken into account, or if only the mildest lesions are considered, a larger proportion of Lower Pecos adults show porotic hyperostosis, a sign of anemia in childhood, than Coastal Plain adults. Overall there are no statistically significant differences by sex for any of the skeletal indicators analyzed with the exception of cribra orbitalia, where males and females for Lower Pecos region are significantly different with significantly fewer males showing cribra orbitalia (0%) than females (33.3%). In analyzing linear enamel hypoplasias, only the mandibular second incisors of Lower Pecos adults were found to have a significantly greater prevalence of hypoplasia than those of the Coastal Plain. A greater proportion of adults from the Coastal Plain show periosteal lesions in the tibia and fibula (30-40%) than those from the Lower Pecos. The results of this bioarchaeological case study indicate that more complex interpretations of health patterning which include important factors such as the osteological paradox, relevant ecological variables, and a framework which stresses the age of occurrence of skeletal indicators within hunter-gatherer groups are vital and relevant to archaeological and bioarchaeological research as a whole. Increasing sample sizes in the future, using sites that are more temporally discrete, and expanding sites used from other ecological regions in addition to drawing on data from stable isotopes may help further this research.
26

Association between transversal dentoskeletal dimensions and Class II severity /

Markic, Goran. January 2009 (has links)
Diss. med. dent. Zürich. / Literaturverz.
27

MiRacles for babies with pulmonary hypoplasia: the effects of miR-10a and miR-200b on lung development

Visser, Robin 14 January 2016 (has links)
INTRODUCTION: Pulmonary hypoplasia causes high morbidity and mortality in congenital diaphragmatic hernia (CDH) patients. MiR-10a and miR-200b are overexpressed in human CDH lungs. We aimed to define their roles in lung development. METHODS: We profiled miR-10a expression with RT-qPCR and in situ hybridization using a nitrofen rat model for CDH. The effects of miR-10a on airway branching were evaluated in lung explants. MiR-200b’s role in airway branching was assessed in miR-200b knockout lung explants. Crossing miR-200b knockout mice with CFP-E-Cadherin was used to evaluate miR-200b’s effects on epithelial differentiation. RESULTS: Expression of miR-10a was altered in the nitrofen model and miR-10a mimics reversed lung hypoplasia in vitro. Heterozygous miR-200b lung explants displayed reduced airway branching. CFP-E-Cadherin/miR-200b knockout lung explants showed reduced epithelial expression. CONCLUSION: Both miR-10a and miR-200b are critical for lung development and CDH. Normalizing their expression may reverse lung hypoplasia and reduce the associated morbidity and mortality in CDH. / February 2016
28

Prevalence and Timing of Enamel Hypoplasias in the Vagnari Skeletal Sample (1st - 4th centuries A.D.)

Nause, Chrystal Lea 01 August 2010 (has links)
This thesis investigates infant and childhood health in the Roman period (1st to 4th centuries A.D.) cemetery at Vagnari using data on the prevalence and timing of linear enamel hypoplasias (LEH‘s). These results are examined in the context of historical and archaeological evidence for childhood health in ancient Rome. Analysis of the prevalence of LEH‘s in 48 individuals reveals a low frequency (64.6 %) of enamel hypoplasias in comparison with other Roman period skeletal samples, suggesting that political–economic or geographical variables may have contributed to the generally healthy conditions for subadults at Vagnari. Intrasite analysis indicates no significant difference between sexes or burial types with respect to the average number of teeth affected with hypoplasias and the average total number of defects, but a significant difference does exist between age groups (divided into 15 year intervals). The hypoplastic data indicate that males and females were experiencing similar levels of stress during infancy and childhood. These results are not consistent with the historical evidence, which suggests that male children were preferentially treated in ancient Roman society. Measurement of each hypoplastic defect indicates a peak age at occurrence of 2.75 years of age, which is interpreted as evidence of the end of the weaning process. Enamel hypoplasias occurred until around 6.5 years of age, suggesting that these Roman children experienced stress throughout childhood, possibly the result of childhood illness or malnutrition. The hypoplastic data are consistent with the historical evidence from the Roman period with respect to the general timetable of weaning. This research integrates biological, archaeological, and historical information about the lives of children to help investigate the physical well–being of a rural working class population in the ancient Roman Empire.
29

Avaliação de dentes decíduos e permanentes traumatizados /

Macari, Karina Silva Moreira. January 2004 (has links)
Orientador: Célio Percinoto / Resumo: É alta a incidência de traumatismos dentários principalmente nas crianças e nos adolescentes, sendo freqüente a ocorrência de complicações em decorrência destes traumas. Assim, realizou-se um estudo clínico e radiográfico de dentes anteriores decíduos e permane ntes traumatizados e também de dentes sucessores a decíduos traumatizados de crianças atendidas na Faculdade de Odontologia de Araçatuba - UNESP e na Fundação Educacional de Barretos - FEB, analisando a ocorrência de seqüelas e os fatores relacionados. For am analisados 333 dentes decíduos, 212 permanentes e 264 sucessores permanentes, os dados registrados em fichas apropriadas e, posteriormente, submetidos à análise estatística. As complicações mais comuns em decorrência de traumatismos na dentição decídua foram a alteração de cor da coroa e a reabsorção radicular patológica. Na dentição permanente foram a fratura coronária e a alteração periapical. As associações de traumatismos (fratura + luxação) foram as maiores responsáveis pela condição de necrose pulp ar tanto na dentição decídua quanto na permanente. A proteção labial do paciente não influenciou na ocorrência de traumatismos, porém o overjet do paciente apresentou influência sobre a dentição permanente. A procura por atendimento imediato foi mais baixa quando do traumatismo acometendo a dentição decídua, com diferença estatisticamente significativa. A freqüência de distúrbios de desenvolvimento observada nos permanentes sucessores foi de 45,8%, sendo a hipomineralização do esmalte a seqüela mais encontr ada, a luxação do tipo intrusiva a que causou mais distúrbios e as faixas etárias mais baixas foram as mais relacionadas com a presença de seqüelas. Houve também uma relação entre a freqüência de hipomineralização do esmalte e a condição pulpar do dente de cíduo traumatizado. / Abstract: It is high the incidence of dental traumatisms mainly in children and in adolescents, being frequent the occurrence of complications due to these traumas. Thus, was carried out a clinical and radiographic study of deciduous and permanent anterior teeth traumatized and also of teeth successors the deciduous traumatized of children assisted at School of Dentistry at Araçatuba - UNESP and at the School of Dentistry of Barretos - FEB, analyzing the occurrence of sequelae and the related factors. 333 deciduous teeth were analyzed, 212 permanent and 264 permanent successors, the data registered in appropriate records and, later, they were submitted to statistical analysis. The most common complications due to traumatisms in the deciduous teething were the alteration of color of the crown and the pathological root resorption. In the permanent dentition the complications were the coronary fracture and the alteration periapical. The associations of traumatisms (fractures + luxation) were the most responsible for the condition of pulpal necrosis in the primary dentition as in the permanent. The patient's labial protection does not seem to influence in the occurrence of traumatisms, however the patient's overjet presented influence on the permanent dentition. The search for immediate service it was lower when the traumatism occurs in the primary dentition, with statistically sig nificant difference. The frequency of development disturbances observed in the permanent successors was 45,8%, being the hypomineralização of the enamel the sequelae mostly found, the dislocation of the intrusive type the one that caused more disturbances and the lowest age groups were the most related with the presence of sequelae. Additionally, there seems to exist a relationship between the frequency of hipomineralização of the enamel and the pulpal condition of the traumatized deciduous tooth. / Doutor
30

Hipoplasia de esmalte em Toxodon Owen, 1837 (Mammalia, Notoungulata) do pleistoceno do estado do Rio Grande do Sul, Brasil

Braunn, Patrícia Rodrigues January 2011 (has links)
A Paleopatologia estuda os sinais de doenças em populações já extintas, entre elas os indicadores de estresse tais como a hipoplasia de esmalte (HE), caracterizada por reduções na espessura do esmalte sobre a superfície dentária, na forma de orifícios, sulcos ou ausência completa de esmalte sobre uma considerável área. Estes defeitos resultam de uma interrupção da atividade dos ameloblastos durante o processo de formação do esmalte devido a estresse fisiológico sistêmico, sendo amplamente utilizados em Paleopatologia Humana e de vertebrados não-humanos como indicativos de estresse ambiental e/ou nutricional. Além disso, com base na histologia do esmalte dentário, é possível relacionar alterações microestruturais neste tecido com o impacto de vários fatores de estresse sobre os ameloblastos secretórios. Toxodon, um grande e robusto mamífero notoungulado herbívoro, com dentes de crescimento contínuo, do Pleistoceno da América do Sul frequentemente tem HE, e a apresenta sob várias formas, tais como linhas ou séries contínuas de orifícios onde o esmalte é mais delgado. Estes defeitos são alternados com áreas de esmalte normal, onde pode haver de uma a seis formas de HE no mesmo dente. Neste estudo foram observados 502 dentes superiores e inferiores de Toxodon pertencentes à Coleção de Paleovertebrados do Museu de Ciências Naturais da Fundação Zoobotânica do Rio Grande do Sul e do Museu da Universidade Federal de Rio Grande, incluindo incisivos, pré-molares e molares de depósitos pleistocênicos da Formação Touro Passo e da Planície Costeira do Estado do Rio Grande do Sul. Os dados obtidos foram comparados com resultados de inspeção macroscópica em 127 dentes superiores e inferiores de Toxodon de depósitos pleistocênicos da região pampeana da Província de Buenos Aires, Argentina, pertencentes ao Museo de La Plata. A classificação de seis tipos de HE observados foi realizada através de exame macroscópico direto e sob um estereomicroscópio. Nos molares superiores predominaram sulcos tênues sobre a superfície bucal, defeitos menos significantes do que aqueles observados nos dentes inferiores. Nos incisivos inferiores foram observados profundos sulcos sobre a superfície bucal em fileiras de orifícios mésio-distais, mostrando alterações cíclicas provavelmente devidas ao crescimento acelerado dos dentes eu-hipsodontes. Nos pré-molares inferiores foram observadas as alterações mais importantes, como séries de fileiras de orifícios verticais e mésio-distais, bem como orifícios distribuídos aleatoriamente. Para estudo comparativo com os resultados macroscópicos obtidos, oito espécimes foram analisados sob microscópio eletrônico de varredura, e sob microscópio óptico, os quais mostraram ocorrência de alterações microestruturais no esmalte. O esmalte subjacente ao orifício próximo de defeitos hipoplásicos era aprismático, perdendo o padrão prisma/interprisma, bem como proeminentes estrias patológicas (Bandas de Wilson) associadas. A condição patológica de sinais de HE em todos os tipos de dentes, com relativamente altas frequências em alguns, indica que provavelmente toxodontes foram expostos a condições severas de estresse, ou, mais provavelmente foi devida ao rápido crescimento dos dentes, os quais eram rapidamente desgastados. / The Paleopathology studies signs of diseases in extinct populations, among them stress indicators, such as enamel hypoplasia (EH), characterized by focal reductions of enamel thickness on the surface of the tooth, in the form of pits, grooves or a complete absence of enamel over a considerable area. These defects result from disruption of ameloblast activity during the process of enamel formation due to systemic physiological stress, being widely used in Human Paleopathology and of non-humans vertebrates as indicative of environmental and/or nutritional stress. On the basis of the histology of tooth enamel it is possible find microstructural changes in this tissue due to the impact of various stress factors on the secretory ameloblasts. Toxodon, a large and robust notoungulate mammalian herbivore, with continuous growing teeth, from the Pleistocene of South America has often EH, in the form of lines or series of pits where the enamel is much thinner. These defects are alternated with areas of normal enamel, where there may be one to six forms on the same tooth. In this study we observed 502 upper and lower teeth belonging to the Museu de Ciências Naturais, Fundação Zoobotânica do Rio Grande do Sul and from Museu da Universidade Federal de Rio Grande paleontological collections; including incisors, premolars and molars, from Pleistocene deposits of Touro Passo Formation and the Coastal Plain of Rio Grande do Sul State. Data were compared with results of macroscopic inspection in 127 upper and lower teeth from Pleistocene pampean region of Buenos Aires Province, Argentina, belonging to the Museu de La Plata. The six types of EH were observed through direct macroscopic examination and under a stereomicroscope. In the upper teeth predominated mild grooves on the buccal surface, which less significant than those observed in the lower teeth. In the lower incisors there were observed deep grooves on the buccal surface in mesiodistal pit rows, showing cyclical changes probably due to accelerated growth of the euhypsodont teeth. In the lower premolars and molars there were observed the most important signs, as a series of vertical and mesiodistal pit rows, as well as randomly distributed pits. For comparative study with the macroscopic results obtained, eight specimens there were analyzed through scanning electron microscopy, and under optical microscopy, which showed the occurrence of microstructural changes in the enamel. The enamel underlying the bottom and the vicinity of hipoplastic defects was aprismatic, lacking a prism/interprism pattern, as well as prominent pathologic striae (Wilson bands) associated. Because there are signs of EH in all types of teeth, with relatively high frequencies in some, this pathological condition indicate that probably toxodonts had been exposed to severe stress conditions, or, much probably, defects were due to a rapid growing of teeth, which were easily abraded.

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