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Laser ablation of modern human cementum: the examination of trace element profilesLefever, Lisa 07 April 2010 (has links)
This study used LA-ICP-MS on a documented sample of modern teeth to sample from a continuous line across the cementum increments thus creating a temporal line graph of the elemental composition against distance. The knowledge of cementum was extended through (1) a more complete elemental composition analysis and (2) the relation of element distribution to the ultrastructure structure throughout the life of a tooth. This study was exploratory and demonstrated that lead, zinc, mercury, and barium follow the same general line of changes, and most likely represent changes in health and exposure to these metals in the general environment. Copper, manganese and vanadium varied very little. Technological limitations prevented the examination of element levels in any one annulation.
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Mineral composition of hypothermally induced ankylosis in rat molars.Leung, Albert January 2010 (has links)
This study used Backscattered electron imaging (BSE) and X-ray Microanalysis to qualitatively and quantitatively investigate morphology and elemental composition of ankylotic adaptation in the periodontium following hypothermic insult to their maxillary first molars. This method has been shown in previous studies to induce aseptic root resorption along with ankylotic changes within the periodontal ligament (PDL). A secondary objective was to assess the pulpal changes that occurred concurrent with the changes in the periodontium. Twenty-eight eight week old Sprague Dawley rats were divided into four groups of seven animals corresponding to one of four observation periods i.e.: t₁= 7 days, t₂= 14 days, t₃= 21 days, t₄ = 28 days. At t=0 days, six animals in each group received a thermal insult as a continuous 20 minute application of dry ice (CO₂ at -81⁰C) to the crowns of their upper right maxillary molar. The untreated left molars were used as controls. The remaining rat within each group did not receive the dry ice. All rats were given two sequential bone labels, calcein 5mg/kg and alizarin red 30mg/kg, administered intraperitoneally 8 days apart. The timing of the labels was such that all rats were euthanased 2 days after the last label. Following sacrifice, the maxillae were dissected out, fixed in ethanol and embedded in methylmethacrylate. Ten microns thick, undecalcified maxillary first molar coronal sections through the furcation were obtained. For every 3 out of 10 sections: the first was left unstained and undecalcified; the second stained with Von Kossa/haematoxylin & eosin; and the third decalcified and stained with haematoxylin & eosin. Unstained sections were viewed under fluorescence, while transmitted light microscopy was used for the other sections. Following initial analysis, the unstained, undecalcified sections were de-coverslipped and carbon coated. These sections were investigated with scanning electron microscopy and Energy Dispersive X-ray Spectrometry (EDS). Quantitative spot analysis and element mapping was performed on alveolar bone, ankylotic areas, cementum and dentine. A linear mixed effects model was employed to investigate any interaction between the four tissues of interest. A focal pattern of ankylosis was observed at days 14 and 21 in three rats. No ankylosis was observed in the control teeth. SEM revealed a focal type of ankylosis with central nodules of mineralized tissue forming within the PDL. Bridging between bone and dentine occurred with fine trabeculae which extended from the central mineralized nodule. Bridging was progressive and was more extensive at day 21 compared to day 14. At day 28, no ankylosis was observed. EDS analysis revealed that the ankylotic tissue was composed of major constituents Calcium and Phosphorous along with trace elements of Mg and Na. This was comparable to the surrounding alveolar bone, cementum and dentine. There was no statistically significant difference in the Ca/P ratios, Mg when ankylotic material was compared to bone. There was a trend towards elevated Na levels in ankylosis but this was not statistically significant relative to bone. Mg in dentine was lower than for all the other tissues and Na was higher in dentine when compared to bone and cementum. In the pulp, hypothermic injury demonstrated alteration of the odontoblast layer, reduction in cellularity, vascular alterations and tertiary dentin formation. At the 28 day observation period, the cellular and vascular changes had returned to levels comparable to the control teeth, indicating successful pulpal healing and regeneration. Marked tertiary dentine deposition was also observed at days 14, 21 and 28. Pulp chambers were visibly smaller due to tertiary dentine formation, however no pulp necrosis was observed. Thus the aseptic root resorption model, using a continuous 20 minute application of dry ice, suggested the occurrence of reversible pulpal tissue alterations compatible with an inflammatory repair process. The observation of ankylosis initiating as centralised nodules within the PDL suggest that the origins may be a consequence of osteogenic potential from PDL stem cells. The null hypothesis that a single, prolonged thermal insult on a rat molar does not have an effect on mineralized tissue formation and that ankylotic tissue is similar to bone was rejected. ABSTRACT There is a presumption that the ankylotic region formed after periodontal ligament (PDL) injury represents an unremarkable bony repair process. Essentially, the injury triggers an osteogenic repair response and the ankylotic tissue merely represents alveolar bone. There is uncertainty whether the oestogenic event is predominantly osteoblast driven, cementoblast directed, or a consequence of osteogenic potential from PDL stem cells. In this study, twenty-eight Sprague Dawley rats were divided into four groups of six animals, corresponding to one of four observation periods, and received a thermal insult as a continuous 20 minute application of dry ice to the crowns of their upper right maxillary molar. The appearance of ankylotic tissues was examined using backscattered electron images using a scanning electron microscope (SEM) equipped with an Energy Dispersive X-ray Analyser (EDS). The Ca, P, and trace elements contents were determined by EDS from four different hard tissue regions: ankylosis; bone; dentine and cementum, and the Ca/P ratios were calculated. Ankylosis was observed at days 14 and 21 in 3 rats and was not seen at day 28. No ankylosis was observed in the control teeth. BSE imaging revealed a focal type of ankylosis with central nodules of mineralized tissue forming within the PDL. The morphological features of ankylotic tissue differed to that of alveolar bone and dentine. Bridging between bone and dentine occurred with fine trabeculae which extended from the central mineralized nodule. EDS analysis showed that the ankylotic tissue was composed of major constituents Ca and P along with trace elements of Mg and Na. This was comparable to the surrounding alveolar bone, cementum and dentine. There was no statistically significant difference in the Ca/P ratios, Mg, and Na between ankylotic material and bone. Statistically significant differences was evident in Mg content between ankylotic material compared to dentine and cementum. Na content was higher in dentine than in ankylotic material. The results of this study indicate that, histochemically, ankylotic material is similar to bone. However, the appearance of ankylotic material as centralised foci with a morphology different from bone suggest that ankylosis may originate from an osteoblastic phenotype originating within PDL. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1522156 / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Denstistry, 2010
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Mineral composition of hypothermally induced ankylosis in rat molars.Leung, Albert January 2010 (has links)
This study used Backscattered electron imaging (BSE) and X-ray Microanalysis to qualitatively and quantitatively investigate morphology and elemental composition of ankylotic adaptation in the periodontium following hypothermic insult to their maxillary first molars. This method has been shown in previous studies to induce aseptic root resorption along with ankylotic changes within the periodontal ligament (PDL). A secondary objective was to assess the pulpal changes that occurred concurrent with the changes in the periodontium. Twenty-eight eight week old Sprague Dawley rats were divided into four groups of seven animals corresponding to one of four observation periods i.e.: t₁= 7 days, t₂= 14 days, t₃= 21 days, t₄ = 28 days. At t=0 days, six animals in each group received a thermal insult as a continuous 20 minute application of dry ice (CO₂ at -81⁰C) to the crowns of their upper right maxillary molar. The untreated left molars were used as controls. The remaining rat within each group did not receive the dry ice. All rats were given two sequential bone labels, calcein 5mg/kg and alizarin red 30mg/kg, administered intraperitoneally 8 days apart. The timing of the labels was such that all rats were euthanased 2 days after the last label. Following sacrifice, the maxillae were dissected out, fixed in ethanol and embedded in methylmethacrylate. Ten microns thick, undecalcified maxillary first molar coronal sections through the furcation were obtained. For every 3 out of 10 sections: the first was left unstained and undecalcified; the second stained with Von Kossa/haematoxylin & eosin; and the third decalcified and stained with haematoxylin & eosin. Unstained sections were viewed under fluorescence, while transmitted light microscopy was used for the other sections. Following initial analysis, the unstained, undecalcified sections were de-coverslipped and carbon coated. These sections were investigated with scanning electron microscopy and Energy Dispersive X-ray Spectrometry (EDS). Quantitative spot analysis and element mapping was performed on alveolar bone, ankylotic areas, cementum and dentine. A linear mixed effects model was employed to investigate any interaction between the four tissues of interest. A focal pattern of ankylosis was observed at days 14 and 21 in three rats. No ankylosis was observed in the control teeth. SEM revealed a focal type of ankylosis with central nodules of mineralized tissue forming within the PDL. Bridging between bone and dentine occurred with fine trabeculae which extended from the central mineralized nodule. Bridging was progressive and was more extensive at day 21 compared to day 14. At day 28, no ankylosis was observed. EDS analysis revealed that the ankylotic tissue was composed of major constituents Calcium and Phosphorous along with trace elements of Mg and Na. This was comparable to the surrounding alveolar bone, cementum and dentine. There was no statistically significant difference in the Ca/P ratios, Mg when ankylotic material was compared to bone. There was a trend towards elevated Na levels in ankylosis but this was not statistically significant relative to bone. Mg in dentine was lower than for all the other tissues and Na was higher in dentine when compared to bone and cementum. In the pulp, hypothermic injury demonstrated alteration of the odontoblast layer, reduction in cellularity, vascular alterations and tertiary dentin formation. At the 28 day observation period, the cellular and vascular changes had returned to levels comparable to the control teeth, indicating successful pulpal healing and regeneration. Marked tertiary dentine deposition was also observed at days 14, 21 and 28. Pulp chambers were visibly smaller due to tertiary dentine formation, however no pulp necrosis was observed. Thus the aseptic root resorption model, using a continuous 20 minute application of dry ice, suggested the occurrence of reversible pulpal tissue alterations compatible with an inflammatory repair process. The observation of ankylosis initiating as centralised nodules within the PDL suggest that the origins may be a consequence of osteogenic potential from PDL stem cells. The null hypothesis that a single, prolonged thermal insult on a rat molar does not have an effect on mineralized tissue formation and that ankylotic tissue is similar to bone was rejected. ABSTRACT There is a presumption that the ankylotic region formed after periodontal ligament (PDL) injury represents an unremarkable bony repair process. Essentially, the injury triggers an osteogenic repair response and the ankylotic tissue merely represents alveolar bone. There is uncertainty whether the oestogenic event is predominantly osteoblast driven, cementoblast directed, or a consequence of osteogenic potential from PDL stem cells. In this study, twenty-eight Sprague Dawley rats were divided into four groups of six animals, corresponding to one of four observation periods, and received a thermal insult as a continuous 20 minute application of dry ice to the crowns of their upper right maxillary molar. The appearance of ankylotic tissues was examined using backscattered electron images using a scanning electron microscope (SEM) equipped with an Energy Dispersive X-ray Analyser (EDS). The Ca, P, and trace elements contents were determined by EDS from four different hard tissue regions: ankylosis; bone; dentine and cementum, and the Ca/P ratios were calculated. Ankylosis was observed at days 14 and 21 in 3 rats and was not seen at day 28. No ankylosis was observed in the control teeth. BSE imaging revealed a focal type of ankylosis with central nodules of mineralized tissue forming within the PDL. The morphological features of ankylotic tissue differed to that of alveolar bone and dentine. Bridging between bone and dentine occurred with fine trabeculae which extended from the central mineralized nodule. EDS analysis showed that the ankylotic tissue was composed of major constituents Ca and P along with trace elements of Mg and Na. This was comparable to the surrounding alveolar bone, cementum and dentine. There was no statistically significant difference in the Ca/P ratios, Mg, and Na between ankylotic material and bone. Statistically significant differences was evident in Mg content between ankylotic material compared to dentine and cementum. Na content was higher in dentine than in ankylotic material. The results of this study indicate that, histochemically, ankylotic material is similar to bone. However, the appearance of ankylotic material as centralised foci with a morphology different from bone suggest that ankylosis may originate from an osteoblastic phenotype originating within PDL. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1522156 / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Denstistry, 2010
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Effect of enamel matrix derivatives (EMD) on collagen GTR-based root coverage procedure a thesis submitted in partial fulfillment ... for the degree of Master of Science in Periodontics ... /Trabulsi, Manal. January 2003 (has links)
Thesis (M.S.)--University of Michigan, 2003. / Includes bibliographical references.
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The ecology and utilisation of Lumholtz's tree-kangaroos Dendrolagus lumholtzi (Marsupialia:Macropodidae), on the Atherton Tablelands, far north QueenslandCoombes, Karen Elizabeth. January 2005 (has links)
Thesis (Ph. D.)--James Cook University, 2005. / Title from PDF title page (viewed on Dec. 3, 2006). Includes bibliographical references (p. 150-204).
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Dental cementum increment analysis and estimating season at death in humansRalston, Claira E 17 February 2016 (has links)
Dental cementum is a mineralized tissue that coats the root of a tooth and anchors it into the alveolar socket via the periodontal ligament. Cementum is continuously deposited and mineralized throughout the life of a tooth, preserving the complex developmental processes of root formation in optically distinct histologic layers (Hillson, 1996; 2005).
Analysis of these features has several anthropological applications, specifically the analysis of cementum increments and their utility in estimating age and season at death in humans for establishing a more specific post-mortem interval (PMI). Wedel (2007) conducted a pilot study to determine whether dental cementum increment analysis can be used to establish season of death in humans. Wedel (2007) hypothesized that by identifying the timing of the transition between the bands of arrested development and the bands of increased deposition, dental cementum increment analysis can be used to identify the season at death in humans. It was demonstrated that cementum increment analysis is 99% accurate in estimating whether an individual died in either a fall/winter or spring/summer season.
The purpose of the present study was to estimate whether cementum bands could accurately be assigned to fall/winter, spring/summer seasons based on their optical properties as being light or dark. A total of 143 teeth of known age and known extraction date drawn from the Boston University Collection and the Antioquia Modern Skeletal Reference Collection in Medellín, Colombia were analyzed using recent protocols for preparation, sectioning, and observing increment lines in cementum.
Dental cementum increment analysis was found to be between 61.54% and 71.15% successful in accurately correlating the nature of the last cementum increment to season at death using a combination of image evaluation and through focus evaluation methods on two distinct geographic samples. A through focus evaluation was found to be more successful at identifying the last band formed and is recommended for microscopic analyses estimating season at death using dental cementum increments. Geographic origin did not have a significant influence over the accuracy of the method to estimate season at death, however the results of this study suggest that teeth extracted from cadavers versus living individuals may have some influence on the accuracy of cementum increments to estimate season at death. No significant influence of sex, age, or tooth type on the identification and correlation of the last band formed were detected in this study. An interobserver analysis using digital images of a randomly selected sample of 45 sections found that interobserver agreement on the nature of the last band formed occurred in only 28.8% of the sample. Inconsistencies in the nature of the last band formed between multiple sections prepared from the same tooth were observed, which calls into question the validity of using cementum increments to estimate season at death.
The potential limitations for the reliability of using dental cementum increment analysis to determine season at death in humans include the lack of a standardized method for preparing adequate sections for viewing cementum increments, and the subjectivity of identifying the last band in a given section. It is concluded that if the validity and reliability of dental cementum increment analysis as a method for age estimation can be established and configured to meet the criteria of the Daubert Standard, specifically in the adoption of a standardized protocol of analysis, then the validity of using this method for estimating season at death can be further considered.
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Avaliação morfométrica e estereométrica dos tecidos periodontais de ratos imunossuprimidos por Tracolimus (FK506)Nassar, Carlos Augusto [UNESP] 15 February 2006 (has links) (PDF)
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nassar_ca_dr_arafo.pdf: 644620 bytes, checksum: c8f926b8b07b13ddf9cd03079f1d6f41 (MD5) / Tacrolimus (FK506) é uma droga imunossupressora usada em transplantes de órgãos e também como terapia alternativa em pacientes com rejeição refratária de enxertos ou intolerância à ciclosporina A (CsA), sem os efeitos adversos atribuídos freqüentemente à CsA. Atualmente não há estudos que explorem os efeitos da administração de FK506 por longos períodos sobre o periodonto. Ë sugerido também que terapias imunossupressivas, principalmente com FK506, possam ser um importante fator no desenvolvimento de Diabetes mellitus pós-transplantes (PTDM). Existem alguns estudos explorando os efeitos do FK506 por longos períodos no desenvolvimento da PTDM em protocolos animais. Assim os objetivos do estudo foram avaliar os efeitos da terapia com FK506 por longos períodos sobre os tecidos gengivais, metabolismo do osso alveolar e do cemento de ratos, bem como os efeitos sobre os níveis glicêmicos. Com relação ao metabolismo ósseo, houve uma tendência de diminuição, estatisticamente significante, dos níveis de ALP em todos os períodos tratados com FK506, sendo que com os níveis de cálcio apenas um aumento em 240 dias de tratamento, quando comparados com os grupos controles. Assim, nós podemos concluir que o FK506 em longos períodos pode levar os efeitos deletérios sobre os tecidos gengivais e pode ser dependente da idade, mas não causaria efeitos negativos sobre o osso alveolar e nem ao cemento. E ainda em relação aos níveis séricos de glicemia, os efeitos negativos da terapia com FK506 também são dependentes do tempo. / Tacrolimus (FK506) is an immunosuppressive drug in organ transplantation and it is also an alternative therapy used for transplant patients with either refractory graft rejection or intolerant to cyclosporine A (CsA), without the adverse effects frequently attributed to CsA therapy. Nevertheless there are not studies exploring the effects of long-term FK506 therapy on periodontium. It has been suggested that immunosuppressive therapy, mainly FK506, may be an important factor in the development of post-transplantation diabetes mellitus (PTDM). There is a lack of studies exploring the effects of a long-term FK506 on PTDM in animal's protocols. The objectives of the present study were to evaluate the effects of long-term therapy with FK506 on the gingival tissue, alveolar bone metabolism and cementum in rats and the deleterious glycemic effects of long-term therapy with FK506. There was a tendency of increase of serum glycemia level in the initial periods (60 and 120 days). Within the limits of this experimental study, it can be concluded that the deleterious gingival effects of FK506 administration may be time and age related side effects and that have not the negative effects of FK506 administration long-term on the alveolar bone and cementum. It can be concluded that the deleterious glycemia effects of FK506 therapy may be time related side effects.
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Análise da regulação de genes associados ao metabolismo do fosfato em células da polpa e ligamento periodontal e suas associações na regeneração periodontal = estudo "in vitro" e "in vivo" / Analysis of phosphate regulation genes in pulp and periodontal ligament cells and their associations with periodontal regeneration : estudo "in vitro" e "in vivo"Rodrigues, Thaisângela 17 August 2018 (has links)
Orientadores: Francisco Humberto Nociti Junior, Karina Gonzales Silvério Ruiz / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-17T15:11:27Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: A formação deficiente do cemento acelular sobre a raiz dentinária de pacientes com hipofosfatasia (HPP) elucida a importância da expressão local da enzima fosfatase alcalina (TNAP) durante a cementogênese. Os objetivos desses estudos foram: i) apresentar dois casos clínicos de perda prematura de dentes decíduos diagnosticados como odonto-HPP; ii) caracterizar diferencialmente o perfil de expressão gênica de células da polpa e ligamento periodontal em indivíduos saudáveis e com HPP em relação a genes envolvidos com o metabolismo do fosfato inorgânico (Pi). iii) caracterizar o reparo e regeneração dos tecidos periodontais em modelo de fenestração periodontal realizado em camundongos com bloqueio do gene da proteína de anquilose (Ank KO). Métodos: i) Pacientes apresentaram esfoliação precoce dos decíduos aos dois anos de idade, mantendo-se em tratamento odontológico rigoroso. Ambos apresentaram baixos níveis séricos de fosfatase alcalina (ALP), porém sem anormalidade esquelética chegando-se ao diagnóstico de odonto-HPP; ii) Análise da expressão de genes associados à homeostasia entre fosfato e pirofosfato (Pi/PPi) foi realizada em tecidos da polpa e ligamento periodontal (PDL) de indivíduos saudáveis. Cultura de células primárias da polpa e PDL obtidas de pacientes saudáveis e com HPP foram estabelecidas para os ensaios de mineralização e expressão gênica; iii) Defeitos de fenestração periodontal (2mm/1mm/0,5mm) foram criados na vestibular de molares mandibulares de camundongos Ank KO e wild-type (WT). Após 15 e 30 dias das cirurgias, as mandíbulas foram coletadas para análise histológica, histomorfometria, avaliação in vivo com marcadores fluorescentes, e imunohitoquímica para proteínas da matriz extracelular. Resultados: i) Cuidados odontopediátricos e terapia periodontal de suporte foram realizados durante 19 anos com o objetivo de prevenir/adiar possíveis perdas de dentes permanentes; ii) Nos tecidos saudáveis, PDL manteve maior e significativa expressão basal para os genes reguladores chaves do PPi quando comparado com a polpa, como fosfatase alcalina (Alpl), proteína de anquilose pregressiva (Ank), e glicoproteína 1 (ectonucleotide pyrophosphatase/phosphodiesterase 1 - Enpp1). In vitro, embora as alterações mais dramáticas fossem encontradas nas células do PDL, tanto as células HPP PDL como HPP-polpa exibiram significativamente baixa atividade de ALP, menor mineralização e expressões reduzidas dos genes associados com a mineralização e regulação do Pi/PPi, comparado ao controle; iii) Grande quantidade de novo cemento foi observada nos camundongos Ank KO após 15 e 30 dias da cirurgia. (p<0,05). Os marcadores fluorescentes indicaram maior atividade de deposição cementária nas áreas dos defeitos nos Ank KO vs. WT. Durante os períodos de 15 e 30 dias de cicatrização, regeneração do cemento e células associadas nos Ank KO recapitularam o padrão de expressão gênica mapeada durante o desenvolvimento, incluindo expressão limitada de BSP e forte OPN e DMP1 na matriz cementária, bem como elevada expressão de NPP1 nos cementoblastos. Conclusões: Dentro dos limites desse estudo, podemos concluir que: i) a perda prematura de dentes decíduos na ausência de desordens esqueléticas pode servir como um sinal inicial crítico para o diagnóstico de odonto-HPP e outros subtipos; ii) os dados sugerem que há uma diferença importante no comportamento in vitro entre as células controle e HPP, incluindo a expressão basal dos genes relacionados ao cemento bem como suas capacidades de promoverem a formação de minerais; iii) Dentro dos limites do estudo, os achados sugerem que níveis reduzidos de PPi local pode promover um aumento da regeneração do cemento. Portanto, a modulação entre Pi/PPi pode ser uma potente abordagem terapêutica para alcançar melhoras na regeneração do cemento. / Abstract: The defective formation of acellular cementum along the tooth root in patients with hypophosphatasia (HPP) have been highlighted the importance of local expression of alkaline phosphatase enzyme (TNAP) for cementogenesis. The aims of these studies were: i) to present two clinical cases that premature loss of primary teeth guided to the diagnosis of odontohypophosphatasia (odonto-HPP); ii) to determine factors contributing to the divergent response of the periodontium and dentin to alterations of phosphate (Pi) metabolism; and iii) to analyze tissue repair and regeneration in a periodontal fenestration model in Ank knock-out (KO) mice. Methods: i) Patients had teeth exfoliation at 2 yearsold, and have been under maintenance visits since then. Both exhibited low levels of serum alkaline phosphatase (ALP) activity, but no additional skeletal abnormalities, prompting a diagnosis of odonto-HPP; ii) Constitutive expression of Pi/PPi-associated genes in periodontal ligament (PDL) versus pulp tissues obtained from healthy subjects were analyzed. Primary cell cultures from control and HPP-PDL and pulp tissues were established to assay mineralization and gene expression; iii) Periodontal fenestration defects (2mm/1mm/0.5mm) were created on the buccal aspects of mandibular molars in Ank KO and wild-type (WT) mice. Mandibles were harvested at 15, and 30 days postsurgery for histology, histomorphometry, evaluation of in vivo fluorochrome labeling, and immunohistochemistry (IHC) for extracellular matrix proteins. Results: i) Pediatric dental care and supportive periodontal therapy were performed during the subsequent 19 years, aimed at avoiding or delaying loss of permanent teeth. ii) In healthy tissues, PDL maintained significantly higher basal expression of key PPi regulators, liver/bone/kidney alkaline phosphatase (Alpl), progressive ankylosis protein (Ank) and ectonucleotide pyrophosphatase/phosphodiesterase 1 (Enpp1), versus pulp. In vitro, although more dramatic changes were found for PDL-harvested cells, both HPP-PDL and HPP-pulp cells exhibited significantly lower alkaline phosphatase activity, mineralization, and depressed expression of genes associated with mineralization and regulation of Pi/PPi, versus control cells. iii) A greater amount of new cementum was observed for Ank KO mice at 15 and 30 days post-surgery (p<0.05). Fluorochrome labeling further indicated a higher appositional activity in the defect areas in Ank KO vs. controls. At days 15 and 30 during healing, regenerating cementum and associated cells in Ank KO recapitulated expression patterns mapped during development, including limited BSP and strong OPN and DMP1 in the cementum matrix, as well as elevated NPP1 in cementoblasts. Conclusions: Within the limits of these studies, we can conclude that: i) premature loss of deciduous teeth in absence of skeletal disorders may serve as a critical trigger sign for diagnosis of odonto- HPP or other subtypes; ii) the data suggest that there are important differences in the in vitro behavior of control versus HPP cells, including basal expression of cementum-related genes as well as their capacity to promote mineral formation; iii) these findings suggest that reduced local levels of PPi can promote increased cementum regeneration. Therefore, local modulation of Pi/PPi may be a potential therapeutic approach for achieving improved cementum regeneration. / Doutorado / Periodontia / Doutor em Clínica Odontológica
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Cirurgia periodontal associada a restauração de ionomero de vidro modificado por resina para tratamento de dentes com recessão gengival e lesão cervical não-cariosa / Periondontal surgery and glass ionomer restoration in the treatment of gingival recession associated with a non-carious cervical lesionSantamaria, Mauro Pedrine 27 February 2007 (has links)
Orientadores: Enilson Antonio Sallum, Marcio Zaffalon Casati / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-09T17:57:17Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: O objetivo desse trabalho foi avaliar clinicamente o recobrimento radicular obtido em recessões gengivais associadas à lesão cervical não-cariosa tratadas com retalho posicionado coronariamente, associado ou não à restauração de ionômero de vidro modificado por resina. Foram selecionados 19 pacientes com recessões gengivais bilaterais comparáveis, associadas à lesões cervicais não cariosas. Os dentes foram distribuídos aleatoriamente para compor o grupo teste: retalho posicionado coronariamente associado à restauração da lesão cervical com ionômero de vidro modificado por resina, ou o grupo controle: retalho posicionado coronariamente associado ao desgaste e regularização da superfície radicular. Os parâmetros avaliados foram: profundidade de sondagem, sangramento à sondagem, nível de inserção clínica, recessão gengival, hipersensibilidade cervical e altura de tecido queratinizado antes dos tratamentos, 45, 60, 90 e 180 dias após. Após 6 meses, as porcentagens médias de recobrimento da altura da lesão cervical não-cariosa foram de 56,14±11,74 para o grupo teste e 59,78±11,11 para o grupo controle, não havendo diferença estatisticamente significante. Foi encontrada diferença (p=0,04) na profundidade de sondagem aos 90 dias em favor do grupo teste. Porém essa diferença não se manteve no período final de avaliação. Foi notada diferença estatisticamente significante quando a hipersensibilidade cervical foi analisada. O grupo teste mostrou-se mais eficaz na resolução desse sintoma (p=0,002). Nos demais parâmetros, não houve diferenças significantes. Dentro dos limites do presente estudo, pode-se concluir que ambos os tratamentos foram efetivos e que a presença da restauração de íonômero de vidro modificado por resina não interfere na taxa de recobrimento quando o retalho posicionado coronariamente é utilizado para tratamento de recessão de tecido gengival classe I de Miller associada à lesão cervical não-cariosa / Abstract: The aim of this study was to evaluate the root coverage and the gingival margin stability after coronally advanced flap with or without glass ionomer restoration to treat gingival recession associated with non-carious cervical lesion. Nineteen patients who presented bilateral gingival recession associated with a non-carious cervical lesion were selected. The sites were randomly assigned to the test group: coronally advanced flap plus the non-carious cervical lesion restoration performed with resin glass ionomer cement or to the control group: coronally advanced flap plus scaling and root planning. Probing depth, bleeding on probing, clinical attachment level, gingival recession, dentin sensitivity and keratinized tissue height were measured at baseline, 45, 60, 90 and 180 days after surgery. Average percentage rates of root coverage for test and control group were 56.14% and 59.78%, respectively. At all postoperative evaluations, both treatments result in significant (p<0.05) recession reduction. No significant statistical difference between test and control was observed regarding root coverage. A significant difference (p=0.04) between test and control was found for probing depth at 90 days. The test group was better; however this difference was not seen at 180 days. A significant difference (p=0.002) was found for dentin sensitivity when control and test were compared. The test group showed better results regarding this parameter. When the other parameters were compared between the two groups, o difference was found. According to the findings of this investigation we can provide hat the presence of the glass ionomer restoration does not interfere with root coverage achieved by coronally advanced fla / Mestrado / Periodontia / Mestre em Clínica Odontológica
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Recrutement, paléodémographie et cémentochronologie : application à un contexte d'inhumation paroissial d'Ancien Régime : Notre-Dame du Bourg à Digne(04) / Funerary admission, paleodemography and cementochronology : application to a Modern parish burial context : Notre-Dame du Bourg at Digne(04)Lanteri, Laëtitia 15 January 2016 (has links)
Plusieurs biais inhérents à l’estimation de l’âge au décès individuel ont conduit à privilégier l’âge populationnel en paléodémographie mais la cémentochronologie a récemment montré une forte corrélation entre âge biologique et âge réel et une précision affinée. L’annualité de l’apposition cémentaire permet de proposer une alternative à la population de référence. Notre objectif consiste à réaliser une étude paléodémographique à partir d’estimations d’âge au décès individuel obtenues par comptage des lignes d’incrément cémentaires. Nous sélectionnons la série ostéoarchéologique moderne de la cathédrale paroissiale Notre-Dame du Bourg à Digne, composée de 563 individus inhumés du XVIe au XVIIIe siècle. Suite à l’analyse des pratiques funéraires, les données des registres paroissiaux exhaustivement dépouillés de 1671 à 1721 sont comparées aux résultats biologiques et paléodémographiques des 421 adultes et 142 immatures. Les archives indiquent une population préindustrielle typique subissant une crise de mortalité en 1691-1692 et un recrutement funéraire aspécifique. L’estimation de l’âge au décès par comptage des lignes d’incrément cémentaires est appliquée à 109 adultes et aux dents déciduales et permanentes de 42 immatures. La distribution probable par âge est obtenue en calculant les probabilités d’appartenance individuelles aux différentes classes d’âges. L’analyse du recrutement est concluante puisque le profil de mortalité par âge obtenu est conforme au schéma de mortalité archaïque et à celui des archives historiques pour les adultes jeunes et matures. Notre approche est novatrice puisqu'elle rétablit l’âge individuel en paléodémographie grâce au cément dentaire. / Several biases related to age estimation led to privilege assessing age structures of populations. But cementochronology provides a better accuracy and a strong correlation coefficient with chronological age. The annual apposition of dental cementum offers an alternative to the reference population. We aim to achieve a paleodemographic study using classical age estimates obtained by cementochronology. We select the modern osteoarcheological series of the cathedral Notre Dame du Bourg at Digne-les-Bains (France), composed by 563 individuals who were buried between the 16th to the 18th century. To monitor the biological results, we examine all the parish registers from 1671 to 1721. After analyzing funerary practices, data from parish records are compared to biological and paleodemographic results from the 421 adults and 142 subadults. Historical records indicate a typical preindustrial population suffering a mortality crisis in 1691-1692. Biological data are consistent with historical sources about an unspecific funerary admission in the cathedral Notre Dame du Bourg. Cementochronology is applied to 109 adults' permanent canines and to 42 subadults' deciduous and permanent single-root teeth. We calculate the probability density function of each individual and belmonging probabilities to every age class. Our interpretation of funerary admission obtained by tooth cementum analysis is conclusive for young and middle-aged adults since the age pattern of mortality is consistent with both the archaic mortality pattern and historical records. Our approach innovates by restoring age estimates in paleodemography through the biological specificity of cementum.
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