O aumento da expectativa de vida vem elevando a ocorrência das alterações degenerativas comuns à terceira idade, como a osteoporose. Essa doença sistêmica também freqüente no hipogonadismo, afeta o metabolismo ósseo comprometendo inclusive a mandíbula. O objetivo deste estudo foi avaliar de que forma a deficiência de esteróides sexuais, induzida por orquiectomia ou ovariectomia, influencia o processo de remodelação óssea da mandíbula de ratos por períodos experimentais crônicos. Ratos Wistar, com 3 meses, foram divididos em três grupos experimentais: controles (C), castrados (ORQ; OVX) e castrados com tratamento hormonal (ORQ + PT - propionato de testosterona, 0,4 mg/100g PC/dia; OVX + BE - benzoato de estradiol, 0,7 g/100g PC/dia). As fêmeas foram previamente avaliadas por citologia vaginal e somente as que apresentaram o ciclo estral regular foram utilizadas. A massa corporal foi verificada semanalmente e ao final dos períodos experimentais (90, 120 e 150 dias) os animais foram sacrificados. O sangue foi coletado e o soro armazenado para posterior análise. As mandíbulas, fêmures e colunas foram excisados, medidos e preparados para análises da densidade mineral óssea e das propriedades físicas e biomecânicas. Observamos que com a castração, machos apresentaram baixo ganho de massa corporal (90d: 12%, 120d: 24% e 150d: 13% a menos que C, p< 0,05), ao contrário das fêmeas (90d: 38% e 120d: 41% a mais que C, p< 0,05). As medidas de todos os ossos foram menores tanto em machos como em fêmeas (&#9794; - 90d: vértebra 11.8%, fêmur 4.4%, côndilo MD 9.4%, côndilo VL 16.6%; 120d: vértebra 13.6%, fêmur 4%, côndilo mandibular MD 9%, côndilo mandibular VL 22.2%; 150d: vértebra 16.8%, fêmur 6% , côndilo mandibular MD 21.6%, côndilo mandibular VL 29.1% e &#9792; - 90d: vértebra 7.7%, fêmur 5.6%, côndilo mandibular MD 29.1 %, côndilo mandibular VL 11.8%; 120d: vértebra 15.9 %, fêmur 6.1%, côndilo mandibular MD 33.6%, côndilo mandibular VL 14.8%; 150d: vértebra 21.6%, fêmur 5.42%, côndilo mandibular MD 29.1%, côndilo mandibular VL 15.1% a menos que C, p< 0,05), em todos os períodos experimentais. Em ambos os sexos as concentrações séricas de esteróides sexuais, fósforo e fosfatase alcalina foram menores em relação ao grupo controle, p<0,05 (Testosterona - 90d: 87%,120d: 87.5%,150d: 90.4%; Estradiol - 90d: 85.8%, 120d: 80.8%, 150d: 71.5%; Fósforo - ORQ - 120d: 7.5%, 150d: 9.2% e OVX 90d: 17.2%, 120d: 16%, 150d: 24%; Fosfatase alcalina - ORQ - 90d: 7%, 120d: 6.8%, 150d: 9.5% e OVX 90d: 21.2%, 120d: 26.1%, 150d: 43.3%). As concentrações séricas de cálcio não diferiram significativamente entre machos, mas foram menores em fêmeas castradas (90d: 13.1%, 120d: 11.7%, 150d: 26.2%, p< 0,05). As análises da densidade mineral óssea (DMO) e das propriedades biomecânicas de vértebras e fêmures apresentaram diminuição mais precoce em fêmeas do que em machos (&#9792; - vértebras a partir de 90d e fêmures a partir de 120d; &#9794; - vértebras a partir de 120d e fêmures a partir de 150, p< 0,05). No entanto, as mandíbulas apenas foram afetadas nos machos aos 150 dias. As propriedades físicas não apresentaram alterações significativas. Concluímos que a perda da função gonadal provoca redução de massa óssea, preferencialmente do osso trabecular, atingindo fêmeas mais precocemente do que machos e acentuando-se com o avançar da idade. O osso mandibular é acometido em períodos crônicos principalmente se estiver associada a um comprometimento da atividade mastigatória. Os efeitos ósseos decorrentes do hipogonadismo foram minimizados pelo tratamento com benzoato de estradiol ou propionato de testosterona, em fêmeas e machos, respectivamente. / The increase in the life expectancy has been raising the occurrence of common degenerative alterations in aging population, as osteoporosis. This systemic disease is also frequent in hypogonadism and affects the bone metabolism, included mandibular bone. The aim of this study was to evaluate how sex steroid deficiency, induced by orchiectomy (ORX) or ovariectomy (OVX), influences on mandible bone remodeling of rats, in groups of chronic experimental periods. Wistar rats, 3 mouths, had been divided in three groups: controls (C), castrated (ORX; OVX) and castrated with hormonal treatment (ORX+TP testosterone propionate, 0,4 mg/100g BW/day; OVX+EB - estradiol benzoate, 0.7 g/100g BW/day). Females were previously evaluated by vaginal cytology and only rats with regular estrous cycle were used. The corporal mass was weekly verified and after experimental periods (90, 120 and 150 days), the animals were sacrificed. The blood was collected and serum stored for posterior analysis. Mandibles, femurs and columns were excised, measured and prepared to analyses of bone mineral density and physical and biomechanical properties. After castration, males presented low gain in body mass (90d: 12%, 120d: 24% and 150d: 13% lower than C, p< 0,05), in contrast of females (90d: 38% and 120d: 41% upper than C, p< 0,05). The measures of all bones were lower in males and in females (&#9794; - 90d: vertebrae 11.8%, femur 4.4%, mandibular condyle MD 9.4%, mandibular condyle VL 16.6%; 120d: vertebrae 13.6%, femur 4%, mandibular condyle MD 9%, mandibular condyle VL 22.2%; 150d: vertebrae 16.8%, femur 6% , mandibular condyle MD 21.6%, mandibular condyle VL 29.1% and &#9792; - 90d: vertebrae 7.7%, femur 5.6%, mandibular condyle MD 29.1 %, mandibular condyle VL 11.8%; 120d: vertebrae 15.9 %, femur 6.1%, mandibular condyle MD 33.6%, mandibular condyle VL 14.8% and 150d: vertebrae 21.6%, femur 5.42%, mandibular condyle MD 29.1%, mandibular condyle VL 15.1% lower than C, p< 0,05), in all experimental periods. Males and females presented serum concentration of sex steroid hormones, phosphate and alkaline phosphatase lower than control group, p< 0,05 (Testosterone - 90d: 87%,120d: 87.5%,150d: 90.4%; Estradiol - 90d: 85.8%, 120d: 80.8%, 150d: 71.5%; Phosphate - ORX - 120d: 7.5%, 150d: 9.2% and OVX 90d: 17.2%, 120d: 16%, 150d: 24%; Alkaline phosphatase - ORX - 90d: 7%, 120d: 6.8%, 150d: 9.5% and OVX 90d: 21.2%, 120d: 26.1%, 150d: 43.3%). No significant differences were found in the males calcium concentration, but it was lower in castrated females (90d: 13.1%, 120d: 11.7%, 150d: 26.2%, p< 0,05).The bone mineral density and biomechanical properties of vertebrae and femur were reduced earlier in females than in males (&#9792; - vertebrae from 90d and femur from 120d; &#9794; - vertebrae from 120d and femur from 150d, p< 0,05). However, mandibles were affected only in 150d males. There werent significant alterations on the physical properties. In conclusion, gonadal function loss caused low bone mass, preferentially in trabecular bone, affected females earliest than males and its decreases more with aging. Mandibular bone is affected in chronic periods principally when associated with masticatory activities alterations. Bones alterations resulted from Hypogonadism were minimized, by estradiol benzoate or testosterone propionate treatment, in female and male, respectively.

A DoenÃa Periodontal (DP) à uma doenÃa inflamatÃria que se relaciona com diversas condiÃÃes sistÃmicas, tais como a osteoporose. A osteoporose induzida por glicocorticÃide (OPIG) à a causa mais importante de osteoporose secundÃria. A Atorvastatina (ATV), fÃrmaco hipolipemiante, apresenta efeitos pleiotrÃpicos, anti-inflamatÃrio e anabÃlico Ãsseo, que podem ser relevantes em prevenir a perda Ãssea em casos de OPIG e DP.O objetivo deste estudo foi avaliar os efeitos da ATV na reabsorÃÃo Ãssea alveolar em ratas com OPIGsubmetidasà DP. AOPIGfoi induzida pela administraÃÃo de dexametasona 7 mg/kg 1x/semana por 5 semanas (i.m.). DPfoi induzida por ligadura ao redor do segundo molar superior esquerdo de ratas por 11 dias. Vinte e quatro animais foram divididos em 4 grupos de 6 animais cada: DP (SHAM OPIG [Salina 0,9% 0,5 ml â i.m.]+DP + Salina [0,9% 2 ml â v.o]); OPIG (DEXA + SHAM DP+Salina); OPIG+ DP (DEXA + DP + Salina); ATV (DEXA + DP + ATV [27 mg/kg â v.o.]) atà eutanÃsia. Os parÃmetros avaliados foram: perda Ãssea alveolar (anÃlise macroscÃpica e radiogrÃfica); expressÃo de citocinas (TNF-&#945; e IL-1&#946;) no tecido gengival; leucograma; nÃveis sÃricos de transaminases, fosfatase alcalina total (FAT) e Ãssea (FAO). AATV preveniu a perda Ãssea em 37,84% (p<0,05).As anÃlises radiogrÃficas corroboraram os achados macroscÃpicos.ATV reduziu a expressÃo deTNF-&#945; (54,88%) e IL-1&#946; (62,55%)na gengiva (p<0,05) e reverteu a neutrofilia (p<0,05). Nenhuma diferenÃa estatÃstica foi observadaquanto aosnÃveis sÃricos de transaminases.ATV (27 mg/kg) aumentou a concentraÃÃo sÃrica de FAT e FAO, quando comparada aogrupo OPIG+DP.Em suma podemos concluir que aATV previniua perda Ãssea alveolar emanimais submetidos a OPIG+DP, por meio de efeito anti-reabsortivo, anti-inflamatÃrio e anabÃlico Ãsseo. / Periodontal disease (PD) is an inflammatory disease that has relationship with several systemic conditions, such as osteoporosis. Glucocorticoid-induced osteoporosis (GIOP) is the main cause of secondary osteoporosis. Atorvastatin (ATV), a hypolipemiant drug, presents pleotropic effects, anti-inflammatory and bone anabolism, which may be relevant in order to prevent bone loss in cases of GIOP and PD. The aim of this study was to evaluate the effects of ATV on alveolar bone loss in rats with GIOP and subjected to periodontitis. GIOP was induced by administration of desametaxone 1 mg/kg 1x/week for 5 weeks (i.m.). PD was induced by ligature around the second left upper molar of rats for 11 days. Twenty-fouranimals were divided in 4 groups of 6 animals each: PD (SHAM GIOP [0,9% Saline 0.5 ml â i.m.] +PD + Saline [0.9% 2 ml â orally]);GIOP (DEXA+SHAM PD+Saline); GIOP + PD (DEXA+PD+Saline); ATV (DEXA + PD + ATV [27 mg/kg â orally]) until euthanasia. The parameters evaluated were: alveolar bone loss (macroscopic and radiographic analysis); cytokine expression on gingival tissue (TNF-&#945; and IL-1&#946;); serum levels of transminases, total alkaline phosphatase (TALP) and bone-specific alkaline fosfatase (BALP). ATV prevented bone loss by 34.84% (p<0.05). The radiographic analysis corroborated the macroscopic findings. ATV reduced the expression of TNF-&#945; (54.88%) and IL-1&#946; (62.55%) in gingival tissue(p<0,05). No statistical difference was observed on serum levels of transminases. ATV (27 mg/kg) raised serum concentration of TALP and BALP when compared to GIOP+PD. In summary, we can conclude that ATV prevented alveolar bone loss in animals subjected to GIOP+PD, through anti-resoprtive, anti-inflammatory and bone anabolic effects

Made available in DSpace on 2014-07-29T15:21:56Z (GMT). No. of bitstreams: 1 Dissertacao Karla F Vasconcelos.pdf: 1466749 bytes, checksum: 7b601b9e8f64b11bffa5aec4d7b36d76 (MD5) Previous issue date: 2010-02-26 / Interproximal and periapical radiographs are most suited to periodontal evaluation, but are limited when it comes to diagnosis of bone condition. In dentistry, cone beam computed tomography (CBCT) has been most frequently used when a threedimensional evaluation is needed. The aim of this study was to compare periapical radiographs and volumetric CT imaging in detecting and localizing alveolar bone loss, by comparing linear measurements of the height, depth and width of the defects and identifying combined bone defects in tomographic images. The images were selected from a secondary database containing images of patients referred for periodontal evaluation. The sample consisted of 51 sites showing both horizontal and vertical bone loss, assessed by three previously-trained examiners. The results showed that there were no statistically significant differences between the imaging methods compared in terms of identification of the pattern of bone loss. However, there were differences between the two methods when the distance between the cementoenamel junction (CEJ) and the alveolar crest (AC) was measured. When the distance between the CEJ and the deepest point and the width of the defect were measured, the methods showed no statistically significant difference. In this study, 30.76% of the 39 teeth evaluated had combined bone defects. It was concluded that the two methods differ when detecting the height of the alveolar bone crest, but present similar views of the depth and width of bone defects. CBCT was the only method that allowed for an analysis of the buccal and lingual/palatal surfaces and an improved visualization of the morphology of the defect. / As radiografias interproximais e periapicais são as mais indicadas para avaliação periodontal, porém apresentam limitações no diagnóstico da condição óssea. A tomografia computadorizada volumétrica tem sido o recurso de imagem mais utilizado quando há necessidade de avaliação tridimensional em Odontologia. O objetivo desse estudo foi comparar radiografias periapicais e imagens tomográficas volumétricas na detecção e localização de perdas ósseas alveolares, por meio da comparação de medidas lineares da altura, profundidade e largura dos defeitos e identificação dos defeitos ósseos combinados nas imagens tomográficas. As imagens foram selecionadas a partir de um banco de dados secundário contendo imagens de pacientes com indicação para avaliação periodontal. A amostra foi composta por 51 sítios apresentando perdas ósseas horizontais e verticais avaliados por três examinadores previamente treinados. Os resultados mostraram que os métodos de imagem comparados não apresentaram diferenças estatisticamente significantes entre si quanto à identificação do padrão da perda óssea. Entretanto, as medidas da distância entre a junção cementoesmalte (JCE) à crista alveolar (CA), apresentaram diferenças entre os dois métodos. Quando comparadas as medidas da distância da JCE ao ponto mais fundo do defeito e da largura do defeito, os métodos não apresentaram diferenças estatisticamente significantes. Neste estudo 30,77% dos 39 dentes avaliados apresentavam defeitos ósseos combinados. Concluiu-se que os dois métodos apresentam diferenças na detecção da altura da crista óssea alveolar, porém com visualização similar da profundidade e largura dos defeitos ósseos. A tomografia computadorizada volumétrica foi o único método que permitiu análise das faces vestibular e lingual/palatina e melhor visualização da morfologia do defeito.

Orientadores: Paulo Henrique Ferreira Caria, Felippe Bevilacqua Prado / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T17:30:42Z (GMT). No. of bitstreams: 1 Freire_AlexandreRodrigues_D.pdf: 4165235 bytes, checksum: 39a64cbf8afdf28035d38f8c66914ac2 (MD5) Previous issue date: 2015 / Resumo: Os fenômenos mecanobiológicos envolvem as características mecânicas do tecido, a nível microscópico, relacionadas às mudanças de metabolismo, apresentando mudanças estruturais e fisiológicas. Os estímulos mecânicos na estrutura óssea implicam na presença de tensões e deformações que resultam alterações na remodelação óssea. Nos tecidos dentoalveolares, especialmente no periodonto de suporte, são conhecidas as alterações estruturais resultantes da perda do equilíbrio da oclusão, especialmente no trauma oclusal. Para entender como ocorrem tais alterações mecânicas e respostas biológicas específicas nestes locais, estudos recentes propõem a aplicação da teoria do mecanostato associada à simulação computacional por análise de elementos finitos. Foram apresentados dois estudos para demonstrar as alterações nos estímulos mecânicos computacionalmente e relacionar com as respostas biológicas que alteraram estruturalmente o osso alveolar de suporte na região dos molares. No primeiro estudo foram utilizados animais que se submeteram à cirurgia de extração do segundo e terceiros molares inferiores, unilateralmente, permanecendo o primeiro molar em oclusal isoladamente, o qual ficou sujeito a um trauma oclusal. A oclusão no primeiro molar foi simulada por análise de elementos finitos e os resultados foram comparados com resultados em análise histológica. O estudo conclui que as regiões com aumento de compressão mecânica devido ao dente estar isolado foram compatíveis com áreas de reabsorção observadas histologicamente. O segundo estudo apresentou um modelo experimental de trauma oclusal em animais com a cimentação de resina sobre a superfície oclusal dos molares superiores, unilateralmente. A mordida posterior foi simulada em análise de elementos finitos para observar os estímulos mecânicos no osso alveolar de suporte tanto no primeiro molar superior quanto no inferior do lado com o trauma. Em comparação foi realizada microtomografia computadorizada para avaliar os efeitos biológicos resultando em alteração estrutura, na qual o volume da crista óssea alveolar foi mensurado. O estudo conclui que aumento da compressão observada computacionalmente, possibilita entender a causa da redução de volume óssea na região de interesse, sendo essa redução maior no molar superior, ou seja, com a presença do material cimentado / Abstract: The mechanobiology phenomena involve the mechanical characteristics of tissue in microscopic level, which is related to changes of metabolism and presenting structural and physiological alterations. The mechanical stimuli in bone structure imply in stresses and strain in the tissue which results in changes in bone remodeling. In dentoalveolar tissues, mainly in the supportive periodontium, the structural changes resulted by the loss of occlusal equilibrium are known. To understand how these mechanical changes occurs and its consequent biological responses, recent studies proposed the application of mechanostat theory associated to computational simulation by finite element analysis. Two studies were presented to demonstrate by computational method the changes in mechanical stimuli and relate to biological responses that resulted in structural changes in the alveolar bone support in molar region. In the first study, animals were submitted to extraction of second and third lower molars, unilaterally, and the first lower molar was kept, which was subject to occlusal stress. The molar occlusion was simulated by finite element analysis and the results were compared with histological analysis. The study concluded that the regions with increase of mechanical compression in isolated molar were compatible with resorption areas in histological observation. The second study presented an experimental model of occlusal stress in animals, where a resin block was cemented on the occlusal surface of upper molars, unilaterally. The posterior occlusion was simulated by finite element analysis to observe the mechanical stimuli both first upper and lower molars, in the same side of occlusal stress. In comparison, the micro-CT was performed to evaluate the biological effect resulting in structural changes, in which the alveolar bone crest volume was measured. The study conclude that the increase of compression, observed in computational analysis, gives the possibility to understand the cause of bone volume reduction in the region of interest, being this reduction was major in the upper molar support tissue, i.e. with the presence of cemented material / Doutorado / Anatomia / Doutor em Biologia Buco-Dental

A Ciclosporina A (CsA) é o medicamento de escolha utilizado no controle da rejeição de órgãos em pacientes transplantados. Efeitos adversos associados ao fármaco, como alterações ósseas e o aumento gengival são fatores de risco para a doença periodontal. O objetivo do estudo foi avaliar o efeito da indução de doença periodontal no tecido ósseo, tecido epitelial e tecido conjuntivo de ratos previamente tratados com a CsA. Foram utilizados quarenta ratos Wistar, com 12 semanas de vida, divididos em quatro grupos (n=10): grupo Controle (GC); grupo Ciclosporina A (GCsA), administração de 10mg/kg de CsA durante sessenta dias a partir do início do experimento; grupo Ciclosporina A Ligadura (GCsAL), inserção da ligadura após trinta dias do início do experimento e administração de 10mg/Kg de CsA desde o início do experimento, durante sessenta dias; grupo Ligadura (GL), inserção da ligadura após trinta dias do início do experimento. Os animais foram sacrificados após sessenta dias por meio de perfusão cardíaca para a realização da análise histológica e histomorfométrica do tecido gengival e tecido ósseo, análise radiográfica do suporte ósseo periodontal e da densidade radiográfica e análise bioquímica da Fosfatase Alcalina. Os resultados foram submetidos à análise de variância (ANOVA, Tukey) a 5% e ao teste não paramétrico de Kruskal- Wallis. Os valores médios para GC (60.5 2.22%) e GCsAL (58.1 2.24%) foram equivalentes entre si para o suporte ósseo periodontal e diferentes de GCsA (55.0 4.44%) e GL (54.8 3.11%) (p=0.0007). Os valores médios da densidade radiográfica não apresentaram diferença estatística significativa (p=0.1776). Em relação à fosfatase alcalina, novamente não foi observada diferença significativa entre os grupos (p=0.2806). Os valores médios de células TRAP+ por grupo experimental, não apresentaram diferença estatística significativa (p=0.3995). Os valores médios para GC (0.29 0.03mm2) e GCsA (0.30 0.02mm2) foram equivalentes entre si para a área do ligamento periodontal e diferentes de GCsAL (0.43 0.17mm2) e GL (0.41 0.11mm2) (p=0.3994). Na área total do tecido gengival, os valores médios para GCsA (0.088 0.033mm2) e GL (0.101 0.034mm2) foram equivalentes entre si e diferentes de GC (0.053 0.020mm2) e GCsAL (0.146 0.047mm2) (p=0.000001). Na proporção área do conjuntivo e área total, os valores médios para GC (28.60 8.64%) foi equivalente ao GCsA (32.72 14.13%) e diferente do GCsAL (38.50 10.98%) e GL (37.70 7.49%) (p=0.0093). Em relação à proporção área do epitélio e área total, os valores médios para GC (71.39 8.64%) foi equivalente ao GCsA (67.27 14.13%) e diferente do GCsAL (61.49 10.98%) e GL (63.37 7.44%) (p=0.0142). Na proporção área do epitélio e área do conjuntivo, os valores médios para GC (2.80 1.13) foi equivalente ao GCsA (2.18 1,32) e diferente do GCsAL (1.89 1.17) e GL (1.81 0.80) (p=0.0334). Baseados nestes resultados pode-se concluir que a exposição prévia a CsA não modificou significativamente a evolução da doença periodontal induzida em ratos. / Cyclosporine A (CsA) is the drug of choice used to prevent organ transplant rejection. Side effects associated to the drug, like bone alterations and gingival overgrowth are considered risk factors to periodontal disease. The objective of the present study was to evaluate the effect of periodontal disease on the bone tissue, epitelial tissue and connective tissue of the rats previously treated with CsA. Forty Wistar rats with 12 weeks were divided into four groups: Control Group (CG, n=10); CsA Group (CsAG, n=10), with CsA (10mg/kg) administration during 60 days since the beginning of the experiment; CsA and Ligature Group (CsALG, n=10), with ligature placement at 30 days after the beginning of the experiment with CsA administration during the whole period; and, Ligature Group (LG, n=10), with ligature placement at 30 days after the beginning of the experiment. After blood sample collection for the biochemical analysis of the Alkaline Phosphatase (PA) activity, the animals were sacrificed by intracardiac perfusion at 60 days after the beginning of the experiment. The mandibles were removed for histologic and histometric analyses of the gingival and bone tissues, and radiographic analysis of the alveolar bone support and density. The data were subjected to analysis of variance (ANOVA, Tuckey) at 5% and to the non-parametric test of Kruskal-Wallis. The mean percentage of alveolar bone support for the CG (60.5 2.22%) was similar to the CsALG (58.1 2.24%) and different to the CsAG (55.0 4.44%) and LG (54.8 3.11%) (p=0.0007). Bone density and PA activity were not statistically different among groups (p=0.1776, and p=0.2806, respectively). The mean values for TRAP+ cells were not statistically different among experimental groups (p=0.3995). The mean values of the periodontal ligament area for CG (0.29 0.03mm2) were similar to the CsAG (0.30 0.02mm2) and statistically different to the CsALG (0.43 0.17mm2) and to the LG (0.41 0.11mm2) (p=0.3994). With regards to the total area of the gingival tissue, the mean values for the CsAG (0.088 0.033mm2) and LG (0.101 0.034mm2) were similar between each other and statistically different to the CG (0.053 0.020mm2) and CsALG (0.146 0.047mm2) (p=0.000001). Regarding the proportion of connective tissue area to the total area, the mean value of the CG (28.60 8.64%) was similar to the CsAG (32.72 14.13%) and statistically different to the CsALG (38.50 10.98%) and to the LG (37.70 7.49%) (p=0.0093). In relation to the proportion of the epithelial tissue area to the total area, the mean value for the CG (71.39 8.64%) was similar to the CsAG (67.27 14.13%) and different to the CsALG (61.49 10.98%) and LG (63.37 7.44%) (p=0.0142). In the proportion of epithelial tissue area to the connective tissue area, the mean value for the CG (2.80 1.13) was similar to the CsAG (2.18 1.32) and different to the CsALG (1.89 1.17) and LG (1.81 0.80) (p=0.0334). Based on these results it can be concluded that previous exposure to CsA did not significantly modify the development of periodontal disease induced in rats.

<p>Osteoporosis causes over two million skeletal fractures in the United States every year in people over 50 years of age. Age-related bone loss results from imbalanced bone turnover mainly caused by decreases in sex hormones and skeletal mechanobiology. Estrogen receptor β (ERβ) in osteocytes (Ot) has been proposed to mediate skeletal structural adaptations in response to estrogen and mechanical stimuli. However, direct <em>in vivo</em> studies on Ot-ERβ are lacking, and relevant <em>in vitro</em> studies are mostly made in two-dimensional (2D) culture models, whose cellular environment restricts Ot morphology and biology. To better understand the mechanisms of estrogen-ERs in age-related bone loss, it is important to investigate the role of Ot-ERβ in skeletal turnover in response to sex hormonal and mechanical cues and develop a novel 3D culture model that can reproduce Ot morphology for future <em>in vitro</em> ER studies. The role of Ot-ERβ in bone turnover and skeletal adaptive response to mechanical load were examined in male and female mice at 12wk and 30wk old. Ot-ERβ shows age- and sex-dependent effects on bone morphology. Young male mice with Ot-ERβ deletion (ERβ-dOT) showed increased vertebral cancellous bone, whereas decreased cortical and cancellous vertebral bone mass appeared in adult male ERβ-dOT mice. No difference in bone mass occurred in female mice between genotypes. Ot-ERβ mediates tibial mechanoadaptation in cortical but not cancellous in young and adult male mice but plays an inhibitory role in young female mice during cortical mechanoadaptation. Gonadectomy studies on young adult mice revealed that deletion of Ot-ERβ inhibits the sex hormone withdrawal-induced decreases in bone mass and skeletal strength for male mice but did not play a major role for female mice. Lastly, a novel 3D <em>in vitro</em> culture system was developed using collagen-mineral composites for investigating culture mineralization, osteocyte biology, and osteocyte-osteoblast interaction. Cell viability and cellular differentiation were validated after 3 days and 56 days of culture. Optimal PSC-HA culture conditions were determined based on osteocyte differentiation, gene expression analyses, and tissue mineralization. Overall, this work takes novel steps to demonstrate the <em>in vivo</em> role osteocyte-ERβ plays in skeletal morphology and mechanobiology and develops a novel <em>in vitro</em> 3D culture using PSC-HA composites. These advances will contribute to future mechanistic studies of sex hormone receptors in osteoblasts and osteocytes in age-related bone loss using controlled <em>in vitro</em> environments. </p>

My PhD dissertation reports my research investigations performed on bone loss projects. 2 projects are described in this thesis. One project dealing with the effect of adipogenic DKK1 on bone loss under normal and under a high-fat-diet (HFD). The 2nd projects aimed to investigate on the potential of miRNAs to be used as potential biomarkers to predict bone fragility in T1D.

No description available.

Mucopolysaccharidosis VI (MPS VI) is a hereditary lysosomal storage disease caused by the absence of the enzyme arylsulfatase B (ARSB). Craniofacial defects are common in MPS VI patients and manifest as abnormalities of the facial bones, teeth, and temporomandibular joints. Although enzyme replacement therapy (ERT) is the treatment of choice for MPS VI, the effects on the craniofacial and dental structures are still poorly understood. In this study, we used an Arsb-deficient mouse model (Arsb m/m ) that mimics MPS VI to investigate the effects of ERT on dental and craniofacial structures and compared these results with clinical and radiological observations from three MPS VI patients. Using micro-computed tomography, we found that the craniofacial phenotype of the Arsb m/m mice was characterized by bone exostoses at the insertion points of the masseter muscles and an overall increased volume of the jaw bone. An early start of ERT (at 4 weeks of age for 20 weeks) resulted in a moderate improvement of these jaw anomalies, while a late start of ERT (at 12 weeks of age for 12 weeks) showed no effect on the craniofacial skeleton. While teeth typically developed in Arsb m/m mice, we observed a pronounced loss of tooth-bearing alveolar bone. This alveolar bone loss, which has not been described before in MPS VI, was also observed in one of the MPS VI patients. Interestingly, only an early start of ERT led to a complete normalization of the alveolar bone in Arsb m/m mice. The temporomandibular joints in Arsb m/m mice were deformed and had a porous articular surface. Histological analysis revealed a loss of physiological cartilage layering, which was also reflected in an altered proteoglycan content in the cartilage of Arsb m/m mice. These abnormalities could only be partially corrected by an early start of ERT. In conclusion, our results show that an early start of ERT in Arsb m/m mice achieves the best therapeutic effects for tooth, bone, and temporomandibular joint development. As the MPS VI mouse model in this study resembles the clinical findings in MPS VI patients, our results suggest enzyme replacement therapy should be started as early as possible.

Radiographic modalities are used in addition to clinical methods to gain information about the patients. In the examination of the periodontium, which is comprised of the gingiva, alveolar bone, periodontal ligament, and cementum, the radiographic examination plays an integral role for diagnosis of periodontal disease. The diagnosis periodontitis is based on a finding of alveolar bone loss. Changes of the alveolar bone can be assessed by different radiographic modalities, such as intraoral radiography (bitewing and periapical radiography) and panoramic radiography. Analysis of alveolar bone loss (alveolar bone level, detection of vertical bone defect and furcation involvement) in radiographic modalities and a systematic review could be helpful to suggest the more applicable radiographic methods for diagnosis of periodontal disease. The purpose of the present study was to examine diagnostic properties of panoramic radiography for the assessment of alveolar bone loss for the diagnosis of periodontal diseases as compare to posterior bitewing radiography. For 96 patients panoramic and posterior bitewing radiographs were performed and results of analysis of visibility of radiographic images and assessment of alveolar bone loss were compared. Also, the systematic review on diagnostic properties of panoramic radiography in the assessment of alveolar bone loss was performed. Based on the results of this study, recommendations for clinical practice and for research were proposed. / Rentgeniniai tyrimo metodai taikomi, kad būtų papildyti klinikinio tyrimo duomenys. Tiriant periodontą, kurį sudaro dantenos, dantinė atauga, periodonto raiščiai ir cementas, rentgeninis tyrimas svarbus diagnozuojant periodonto ligas, nes jo metu nustatomi dantinės ataugos pokyčiai. Dantinės ataugos pokyčiams vertinti daromos rentgeno nuotraukos taikant vidinių burnos rentgeno nuotraukų darymo metodus, t. y. kandimo ar dantų šaknų rentgeno nuotraukų darymo metodus, ir išorinės burnos rentgeno nuotraukos darymo metodą, t. y. panoraminės rentgeno nuotraukos darymo metodą. Atlikus dantinės ataugos pokyčių (kaulo lygio arba rezorbcijos, kaulo defekto ir tarpšaknio kaulo pažeidimų) analizę, taikant rentgeninius metodus, ir padarius sisteminę literatūros apžvalgą, galima būtų pasiūlyti tinkamiausią rentgeno metodą periodonto ligoms diagnozuoti. Šio darbo tikslas – ištirti ir palyginti panoraminės rentgeno nuotraukos ir kaplių bei krūminių dantų rentgeno nuotraukų darymo metodų diagnostikos ypatybes vertinant dantinės ataugos pokyčius periodonto ligoms diagnozuoti. Kiekvienam, iš 96 pacientų įtrauktų į tyrimą, buvo padaryta panoraminė rentgeno nuotrauka ir kaplių bei krūminių dantų kandimo rentgeno nuotraukos. Atlikta dantinės ataugos rentgeno atvaizdo vizualioji kokybė analizė ir vertinimai skirtingose rentgeno nuotraukose bei palyginti rezultatai. Padaryta sisteminė literatūros apžvalga apie panoraminės rentgeno nuotraukos vertę diagnozuojant periodonto ligas. Pagal šio tyrimo... [toliau žr. visą tekstą]