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Beta thalassemia-induced osteoporosis: evaluating current and novel therapeutic optionsKhullar, Natasha 03 November 2016 (has links)
Osteopenia and/or Osteoporosis (OOS) is becoming an increasingly prevalent chronic disease among Beta Thalassemia Major (BTM) patients, especially now that life expectancy in these patients has considerably improved through regular blood transfusions and iron chelation therapy. With several, complex genetic and acquired factors involved in its pathogenesis, coupled with the heterogeneity in the clinical response of BTM patients to different pharmacological agents, OOS has proven to be particularly difficult to treat. The great majority of treatment options currently available are not curative, but instead are aimed towards managing the symptoms and progression of the disease in patients. General preventative measures, such as iron chelation therapy and hormonal replacement therapy (HRT), are instrumental aspects of the treatment plan; however, the incredible complexity of OOS necessitates an individualized, multidisciplinary approach to management, with a principal therapy that is safe and effective in patients, and that is accompanied by these other supportive measures. This review, through a comprehensive analysis of current literature, includes data from randomized, placebo-controlled trials, double blind and observational clinical studies, and suggests optimal therapeutic interventions for first-line management of OOS. It also addresses treatment options for BTM patients in whom resistance to the recommended first-line therapy develops, or who display secondary endocrine conditions contributing to OOS. In addition to providing a current synopsis of OOS management and the potential of emerging treatment options, this analysis highlights some of the limitations of traditional therapies. In this way, the paper effectively illustrates the current status of TM-induced OOS; it describes what is or isn’t working, as well as underscores the diagnostic and therapeutic challenges continually faced by patients, researchers and clinicians.
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Associação entre osteoporose e doença periodontal em mulheres na pós-menopausa / Association between osteoporosis and periodontal disease in postmenopausal womenJuliana Cleaver Aun 30 August 2010 (has links)
Este estudo caso-controle teve como objetivo principal investigar se existe associação entre a doença periodontal (DP) e a osteoporose em mulheres na pós-menopausa. A amostra consistiu em 142 mulheres na pós-menopausa: 74 no grupo caso (com DP) e 68 no grupo controle (sem DP). O exame clínico periodontal completo foi realizado, utilizando os seguintes parâmetros clínicos: profundidade clínica de sondagem (PCS), distância da junção esmalte-cemento (JEC) até a margem gengival (MG), nível clínico de inserção (NCI), sangramento à sondagem (SS), índice de placa e índice de cálculo supragengival. A densidade mineral óssea (DMO) foi mensurada através das medidas de absorciometria por raios X com dupla energia e o diagnóstico de osteoporose feito de acordo com o critério da Organização Mundial de Saúde (OMS). As variáveis preditoras foram consideradas em um ajuste de regressão logística. Não foi observada diferença entre os grupos para osteoporose (p = 0,473). Identificou-se associação com DP para presença de cálculo supragengival em 20% até 50% dos sítios (Odds ratio [OR] = 2,40; intervalo de confiança [IC] 95%: 1,07-5,39) ou acima de 50% dos sítios (OR=2,99; IC 95%: 1,19-7,56) e menor escolaridade (OR=2,53; IC 95%: 1,17-5,43). Os resultados sugerem que não existe associação entre DP e osteoporose. A presença de cálculo supragengival e menor escolaridade foram indicadores de risco para a DP neste grupo de mulheres na pós-menopausa. / This case-control study investigated the association between periodontal disease and osteoporosis in postmenopausal women. The sample consisted of 142 postmenopausal women: 74 in the case group (with periodontal disease) and 68 in the control group (no periodontal disease). The complete periodontal clinical examination was performed using measurements of probing depth, distance of enamel-cement junction to gingival margin, clinical attachment loss, bleeding index, plaque index and supragingival calculus index. Bone mineral density was measured by Dual Energy X-ray Absorptiometry and osteoporosis diagnosis was performed using World Health Organization criteria. The predictor variables were considered in an adjustment of Logistic Regression. No difference between groups regarding osteoporosis (p = 0.473) was observed. The logistic regression analysis identified association of periodontal disease with supragingival calculus in 20% to 50% of sites (OR = 2.40; 95% confidence interval [CI]: 1.07-5.39) or over 50% of sites (OR = 2.99; 95% CI: 1.19-7.56) and low education (OR = 2.53; 95% CI: 1.17-5.43). The results suggest that there is no association between periodontal disease and osteoporosis. Presence of supragingival calculus and low educational level were risk indicators for periodontal disease in this group of postmenopausal women.
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Bone Quality Assessment Using High Resolution Peripheral Quantitative Computed Tomography (HR-pQCT)Zhou, Bin January 2015 (has links)
Osteoporosis is a major metabolic bone disease that causes reduced bone mass, deteriorated bone microstructural and increased fracture risk. In clinical practice, the gold standard to examine bone quality and evaluate fracture risk is using dual energy X-ray absorptiometry through measurements of areal bone mineral density (aBMD). However, it has been well accepted that in addition to aBMD, bone geometry, microstructure and material properties also play important roles in determining overall bone mechanical competence, which is directly related to fracture risk. High-resolution peripheral quantitative computed tomography (HR-pQCT) has the capability to image three-dimensional (3D) bone microstructures in vivo and provide quantitative measurements of bone mineral density as well as cortical and trabecular microstructure. Based on the HR-pQCT images, micro finite element (µFE) models can be constructed to directly estimate bone strength. HR-pQCT has become a widely used imaging tool in clinical research to evaluate the effect of aging, drug treatment, and metabolic bone disease on bone quality. The work in this thesis focuses on evaluating the accuracy and capability of HR-pQCT in quantifying microstructural properties of human radius and tibia bone, exploring its prediction power of whole bone strength and discussing potential applications in clinical studies.
In this thesis, we quantified the accuracy of the standard HR-pQCT microstructural measurements of human distal radius and tibia through comparisons with gold standard µCT-based morphological measures. The results showed that the BV/TVd, Tb.N*, Tb.Th and Tb.Sp from HR-pQCT were significantly and highly correlated with those from gold-standard µCT measurements. Strong correlations between the HR-pQCT µFE predictions and direct mechanical testing measures suggest that HR-pQCT µFE is a robust method to determine bone mechanical properties.
In a clinical setting, standard HR-pQCT scans are performed on the non-dominant wrist (usually the left) and the corresponding tibia. However, the contralateral side is selected for scanned when there is a fracture the non-dominant wrist. It remains unclear whether the dominant side is representative of the non-dominant side and how much error it will bring into a study where subjects include mixed scans of both sides. In this thesis, we applied HR-pQCT and µCT based morphological and mechanical measurements to characterize the symmetric nature of distal radius and tibia. We found that the right radius tend to be larger than the left radius. However, at the tibia, the bone size was found to be similar between left and right. By micro computed tomography (µCT), microstructural parameters such as BV/TV were also found to be larger at the right radius, while no difference was found at the tibia. Trabecular number, trabecular thickness, trabecular separation and cortical thickness were not different between left and right radius. µFE analyses demonstrated that stiffness and strength of right radius were significantly higher than left radius, while there was no difference at the tibia.
The standard clinical region of interest HR-pQCT is recommended by the manufacturer; however, it is not clear whether a segment HR-pQCT scan is representative of whole bone mechanical properties. Therefore we quantified the associations of microstructural and mechanical measurements of the radius and tibia segments with whole bone stiffness and examined if we can improve the correlation when we select a different region. The microstructural and mechanical measurements at the two regions next to the standard HR-pQCT segment (proximal and distal) were also examined. The results showed that the bone microstructure from proximal and distal sections is highly correlated to standard region at both distal radius and tibia. The mechanical properties of the three segments were strongly correlated with overall bone mechanical properties. The microstructural measurements at the most distal section were correlated with whole bone stiffness better compared to those from standard and proximal regions.
DXA is incapable of discriminating patients with wrist fracture from those without. In this study, we examined the microstructural and mechanical properties in patients with and without wrist fracture through HR-pQCT based analyses. We demonstrated that wrist fracture patients had lower plate and rod bone volume fraction, less plate and rod trabecular number, thinner cortex and lower whole bone stiffness and strength, compared to healthy controls. Failure analyses also depicted significantly lower trabecular plate compression and tension failure fraction in wrist fracture patients.
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Plate-Rod Microstructural Modeling for Accurate and Fast Assessment of Bone StrengthWang, Ji January 2016 (has links)
Progressive bone loss and weakening bone strength associated with aging predispose the elderly population to osteoporosis and millions of costly fragility fractures. Micro finite element (µFE) analysis based on clinical high-resolution skeletal imaging provides an accurate computational solution to assessing the mechanical properties of bone, which can be used as the dominant factors for fracture risk. However, the current µFE analysis technique is impractical for clinical use due to its prohibitive computational costs, which result from the “voxel-to-element” approach of modeling human bone regardless of its microstructural pattern. I developed a novel plate-rod microstructural modeling technique for highly efficient patient-specific µFE analysis and translated it to clinical research for the assessment of bone strength in osteoporosis and fragility fractures.
Trabecular microstructure is composed of interconnected plate-like and rod-like trabeculae. Instead of converting every image voxel directly into an element, the plate-rod modeling approach created mechanical characterization for every individual trabecular plate and rod. The validation studies demonstrated that the PR model was able to reproduce the morphology and mechanical behavior of the original trabecular microstructure, while reducing the size of the µFE model and improving the efficiency of µFE simulations. First, the PR models of trabecular bone were developed based on high-resolution micro computed tomography (µCT), and evaluated in comparison with computational gold standard-voxel µFE models and experimental gold standard-mechanical testing for estimating Young’s modulus and yield strength of human trabecular bone. Results suggested that PR model predictions of the trabecular bone mechanical properties were strongly correlated with voxel models and mechanical testing results. Moreover, the PR models were indistinguishable from the corresponding voxel models constructed from the same images in the prediction of trabecular bone Young’s modulus and yield strength. In addition, PR model nonlinear µFE analyses resulted in over 200-fold reduction in computation time compared with voxel model µFE analyses.
In the effort of studying the heterogeneous bone mineralization in trabecular plates and rods, I developed an individual trabecula mineralization (ITM) analysis technique that allows quantification of the tissue mineral density of each individual trabecular plate and rod. By examining the variation of mineral density with trabecular types and orientations, it was found that trabecular plates were higher mineralized than trabecular rods. Furthermore, trabecular plate mineral density varied with trabecular orientation, increasing from the longitudinal direction to the transverse direction. ITM provided measurement of mineral density of each trabecular plate and rod, which was converted to trabecula-specific tissue modulus and used in the PR models to incorporate mineral heterogeneity in µFE simulations. Results suggested that heterogeneous PR models did not differ from the homogeneous PR models or specimen-specific PR models in their predictions of apparent Young’s modulus and yield strength of the human trabecular bone specimens from non-diseased donors.
Based on the trabecular bone PR model, a whole bone PR model was developed for assessing whole bone mechanical strength at the distal radius and the distal tibia from high-resolution peripheral quantitative computed tomography (HR-pQCT). The accuracy of the whole bone PR model was evaluated on human cadaver radius and tibia specimens which were imaged using HR-pQCT and µCT, respectively, and tested to failure. The whole bone stiffness and yield load of the radius and tibia segments predicted by HR-pQCT PR models were strongly correlated with those predicted by corresponding HR-pQCT voxel models, µCT voxel models, and mechanical testing measurements. The PR models µFE results were indistinguishable from the voxel models constructed from the same HR-pQCT images. Moreover, the PR models significantly reduced the computational time for nonlinear µFE assessment of whole bone strength. After evaluating the accuracy and efficiency of the newly developed whole bone PR model, it was employed in a clinical study aimed at characterizing the abnormalities of trabecular plate and rod microstructure, cortical bone, and whole bone mechanical properties in postmenopausal women with vertebral fractures. Women with vertebral fractures had thinner cortical bone, and larger trabecular area compared to their non-fractured peers. ITS analyses suggested vertebral fracture subjects had deteriorated trabecular microstructure, evidenced by fewer trabecular plates, less axially aligned trabeculae and less trabecular connectivity at both radius and tibia. These microstructural deficits translated into reduced whole bone stiffness and yield load at radius and tibia as predicted by PR model nonlinear µFE simulation. More importantly, logistic regression indicated that whole bone yield load was effective in discriminating the vertebral fracture subjects from the non-fractured controls.
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Impact des acides gras sur le métabolisme osseux / Impact of fatty acids on bone metabolismWauquier, Fabien 16 December 2011 (has links)
Dans le contexte actuel d’allongement de l’espérance de vie, la prévalence des maladies liées à l’âge telles que l’ostéoporose est de plus en plus importante. Le coût de la prise en charge de ces pathologies constitue un problème de santé public majeur et la mise en place de stratégies de prévention nutritionnelle adaptées apparaît comme une excellente solution alternative aux traitements habituels. Pourtant, l’étude des activités biologiques des nutriments reste trop marginale pour certains tissus et certaines catégories de molécules, c’est notamment le cas du tissu osseux et des lipides, en particulier les acides gras.Ces derniers sont pourtant capables de moduler le devenir du tissu osseux que ce soit indirectement par des mécanismes systémiques ou directement au niveau de la cellule osseuse. La perte osseuse liée au vieillissement est souvent associée à l’établissement progressif d’une inflammation chronique à bas bruit à l’échelle de l’organisme. Dans ce contexte, les niveaux de cytokines pro-inflammatoires telles que l’interleukine 6 ou le Tumor Necrosis Factor α sont augmentés et ces composés, qui sont connus pour induire la résorption osseuse, pourraient contribuer à la dégradation du squelette. Notre hypothèse de travail était que certains Acides Gras Poly-Insaturés (AGPI) à propriétés anti-inflammatoires pouvaient éventuellement limiter l’inflammation chronique associée au vieillissement et ainsi contribuer à préserver le capital osseux. Dans cette optique, nous avons utilisé la souris SamP8 qui est un modèle de progeria présentant, à douze mois, un phénotype ostéoporotique. Dans ce modèle, l’administration d’un régime délétère à base d’huile de tournesol (ratio acide gras ω6 /ω3 très important) aggrave la perte osseuse en association avec une augmentation des marqueurs inflammatoires systémiques et osseux ainsi qu’une augmentation des marqueurs de la résorption osseuse. La supplémentation de ce régime tournesol avec de l’huile de bourrache ou de l’huile de poisson permet d’apporter des quantités importantes d’AGPI anti-inflammatoires (acide γ-linoléique pour l’huile de bourrache et ω3 pour l’huile de poisson). De manière intéressante, ces deux régimes supplémentés permettent, en plus de réduire les paramètres inflammatoires, de s’opposer à l’augmentation des marqueurs de résorption osseuse et de limiter la diminution de la densité minérale de l’os chez ces souris. Cette étude met donc en évidence le potentiel santé de certains AGPI au regard de la préservation du capital osseux et suggère un rôle déterminant de leurs propriétés anti-inflammatoires systémiques. En parallèle, la description des effets directs des acides gras au niveau cellulaire par l’activation de récepteurs spécifiques occupent une place croissante dans la littérature. Récemment, le récepteur membranaire GPR40 (G Protein coupled Receptor 40) a été mis en évidence pour ses interactions avec les acides gras libres à longues chaînes et nous avons pu montrer son expression dans les précurseurs ostéoclastiques. Nous avons donc émis l’hypothèse que ce récepteur pourrait jouer un rôle dans la médiation des effets des acides gras sur les paramètres du remodelage osseux. Ce travail a permis de mettre en évidence l’existence d’un phénotype ostéoporotique chez la souris invalidée pour le GPR40. L’effet protecteur de ce récepteur semble lié principalement à un effet inhibiteur de son activation sur la différenciation des ostéoclastes. En effet, l’utilisation de l’agoniste spécifique du GPR40 empêche in vitro la différenciation ostéoclastique par RANKL de deux modèles cellulaires de manière GPR40-dépendante. De surcroit, cet agoniste est également capable in vivo de s’opposer à une perte osseuse induite chez la souris. Ces résultats révèlent pour la première fois l’implication du récepteur GPR40 dans la physiologie osseuse et apportent la connaissance d’une nouvelle possibilité de modulation directe des cellules osseuses par les acides gras. / With increasing lifespan, prevalence of age-related complications has grown including skeletal defects such as osteoporosis. Socio-economic consequences of these disorders represent a major public health problem worldwide and in this context, nutritional prevention strategies may be considered as a good option to be associated with usual therapies. However, biological activities of some nutrients have been too poorly deciphered in regards to their bone health potential. This is notably true concerning fatty acids and both their direct and indirect relationships with the skeleton. Age-related bone complications are often associated with a gradual establishment of a systemic low-grade inflammatory condition. This leads to high levels of pro-inflammatory cytokines such as interleukin 6 or tumor necrosis factor α which are known to favour osteoclast-induced bone resorption. Then, these high pro-inflammatory cytokines levels may contribute to age associated bone loss. We hypothesize that in this context, poly-unsaturated fatty acids (PUFA) with known anti-inflammatory properties may counteract both the low-grade inflammation establishment and the associated bone loss. Thus, animals from the progeria mouse model SamP8 were used and were shown to exhibit osteoporosis at twelve months. Feeding these mice with a deletary (very high ω6/ω3 ratio) sunflower oil-based diet results in an exacerbated bone loss, associated with increased systemic and bone inflammation parameters as well as increased bone resorption markers. Either borage or fish oil supplementation of the sunflower oil-based diet result in high amounts of anti-inflammatory PUFAs in the diet (γ-linoleic acid with borage oil and ω3 with fish oil). Interestingly, mice fed with the two “supplemented” diets show reduced inflammatory parameters but also reduced levels of bone resorption markers and preserved bone mineral density. In this work, the bone health potential of some PUFAs was established and was linked to their systemic anti-inflammatory properties. Besides, fatty acids are increasingly studied as signalling molecules, able to modulate cell signalling by their interactions with specific receptors. A few years ago, long chain fatty acids were shown to be ligands of the membrane bound fatty acid receptor GPR40 (G Protein coupled Receptor 40). As we showed GPR40 expression in osteoclast precursors, we hypothesized that it may be involved in fatty acid-induced bone remodelling regulation. In this study, an osteoporotic phenotype was found in GPR40-deficient mice. This GPR40- mediated bone protection seems to involve an anti-osteoclastogenic effect. As a matter of fact, a GPR40 specific agonist led to blunted RANKL-induced osteoclastic differentiation in a GPR40-dependant way. In addition, this agonist was also able in vivo to counteract ovariectomy-induced bone loss in mice. Thus, involvement of GPR40 in bone remodelling was established for the first time in this work, bringing to light a new mechanism in the fatty acid-induced modulation of bone metabolism.
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Effect of low-magnitude high-frequency vibration on fracture healing in normal and osteoporotic bones. / CUHK electronic theses & dissertations collectionJanuary 2008 (has links)
Bone fracture, particularly that occurring in osteoporotic conditions, has become a major health issue. Fracture healing is a well-orchestrated regenerative process, the enhancement of which has been one of the major goals in fracture management. Low-magnitude high-frequency vibration (LMHFV) is osteogenic for intact bone and beneficial for limb blood circulation, which implies a potential of enhancement for fracture healing. Three parts of the experiments were conducted in this study to test the hypothesis that LMHFV would accelerate fracture healing by promoting chondrogenesis, endochondral ossification, and remodeling in both normal and osteoporotic bones. / Part I study. Three-month-old female SD rats underwent closed femoral fracture and were randomized into either vibration group (VG-I, 35Hz, 0.3g, 20min/day, 5days/week) or sham-treated control group (CG-I). Femora were harvested at 1, 2 and 4 weeks for micro-CT analysis, histomorphometry, and mechanical testing. Part II study. Osteoporotic model was established in nine-month-old SD rats after three months of inducement following ovariectomy. Similar grouping (VG-II and CG-II) and treatment regimes were performed after fracture, with the femora harvested at 2, 4 and 8 weeks for assessments like those in the Part I study. Part III study. After fracture, 3-month-old female SD rats were grouped (VG-III and CG-III) and treated as in the Part I study. At 1, 2 and 4 weeks, femora were collected for gene quantification (Col-1, Col-2, BMP-2, VEGF, and TGF-beta1) using real-time PCR. Type I and II collagens were located immunochemically in histological sections. / Results of the Part I and II studies demonstrated that LMHFV promoted callus formation (together with chondrogenesis), mineralization (endochondral ossification), and remodeling, which led to faster healing and better mechanical outcomes in both normal and osteoporotic fractures. In molecular level, the effect of LMHFV was reflected by the stimulation of chondrogenesis and osteogenesis related matrix collagen formation and growth factor expression. The molecular data echo Part I and II findings well. This study proved that LMHFV accelerated fracture healing by promoting chondrogenesis, endochondral ossification, and remodeling in both normal and osteoporotic bones, and indicated great potential of its future clinical application on fracture healing. / Shi, Hongfei. / Adviser: Kwok-Sui Leung. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3422. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 180-201). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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Influência do consumo crônico de etanol 20% na doença periodontal induzida em ratas com deficiência estrogênicaAlonso, Juliana Madureira de Souza Lima [UNESP] 23 October 2009 (has links) (PDF)
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alonso_jmsl_dr_sjc.pdf: 1064371 bytes, checksum: 4b5574d1963cb808bb8dd39cc9e27047 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Condições sistêmicas do hospedeiro podem modular a resposta inflamatória periodontal, determinando variação em relação à susceptibilidade individual e velocidade de progressão da doença periodontal. Dentre os fatores sistêmicos adquiridos, a osteoporose e o alcoolismo são descritos na literatura, como indicadores de risco para a perda óssea associada à doença periodontal. Este estudo objetivou analisar, para ratas Wistar, a influência do consumo crônico do etanol 20% associado à deficiência estrogênica considerando aspectos histológicos e histomorfométricos. Foram utilizadas sessenta ratas, com aproximadamente noventa dias, divididas em dois grupos correlacionados à cirurgia (OVZ) ou simulação cirúrgica de ovariectomia (SHAM). Cada grupo foi dividido em três subgrupos: (C) dieta controle, (A) dieta alcoólica 20% e (I) solução isocalórica ao etanol 20%. Após trinta dias da castração, iniciou-se a dieta e indução de periodontite experimental no primeiro molar inferior esquerdo, as quais foram mantidas por 56 dias. As regiões interproximais entre primeiro e segundo molar inferior esquerdo e o sítio contralateral sem indução da doença periodontal foram avaliadas quanto ao nível ósseo, perda de inserção e características inflamatórias. Os resultados demonstraram que em relação à significância para SHAMC e OVZ-C, a deficiência hormonal não foi capaz de induzir ou agravar a perda óssea na doença periodontal, mas acarretou alterações inflamatórias importantes. Considerando os grupos SHAM e OVZ e a ausência de doença periodontal, o etanol acarretou perda óssea e alterações inflamatórias para ambos os grupos, sendo observada maior severidade quando combinado à ovariectomia. Nas ratas com periodontite induzida, OVZ ou SHAM... / The immune system has an important paper in pathogenesis of the periodontal disease, being the host can modulate periodontal inflammatory reaction, determining variance to individual susceptibility and speed of progression of the periodontal disease. Amongst systemic acquired factors, osteoporosis and alcoholism are described in the literature, as risk indicators for bone loss associated with periodontal disease. The purpose of this study was evaluate histological and histomorfometrics aspects on influence of the chronic alcohol consumption in the ligature-induced periodontitis in rats with estrogen deficiency for. Sixty rats were used, with approximately 90 days-old, divided into two groups correlated surgery (OVZ) or surgical simulation of ovariectomy (SHAM). Each group was divided into three subgroups groups (C) control diet, (A) ethanol 20% containing liquid diet and (I) par-fed control diet. After thirty days of castration, diet and experimental periodontitis induction, which were maintained by 56 days. Interproximal regions between first and second molar lower left and the respective contralateral site without induction of periodontal disease were assessed as to the level osseous insertion loss and inflammatory characteristics. The results showed that in relation to the significance to SHAM-C and OVZ-C, hormone deficiency was not able to induce or aggravate the bone loss, but periodontitis has resulted in important inflammatory changes. Whereas the groups SHAM and OVZ and the absence of periodontitis, ethanol has resulted in bone loss and inflammatory changes to both groups, and also greater severity when combined with ovariectomy. In rats periodontitis induction, OVZ or SHAM, the 20% ethanol consumption doesn’t affect exacerbate bone... (Complete abstract click electronic access below)
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Estabelecimento de um índice quantitativo e qualitativo para auxiliar no diagnóstico da osteoporose em radiografia panorâmica / Establishment of a quantitative and qualitative index for the diagnosis of osteoporosis in panoramic radiographyLituania Fialho de Miranda 12 August 2011 (has links)
Recentemente, a osteoporose tem sido apontada como fator associado a manifestações bucais representadas pela perda óssea, especialmente na mandíbula. Entretanto, as técnicas de avaliação direta da densidade mineral óssea mandibular ainda não demonstraram boa precisão e acurácia. O presente trabalho teve como objetivo avaliar, por meio de um estudo descritivo-analítico, a possibilidade da utilização das radiografias panorâmicas, como um método capaz de expressar as alterações morfológicas da mandíbula decorrentes da idade e estabelecer um único índice quantitativo e qualitativo, para identificar os casos de osteopenia e osteoporose. A pesquisa ocorreu em mulheres em período de menopausa e pós-menopausa em tratamento odontológico nas clínicas odontológicas da faculdade de Odontologia da Universidade de São Paulo, no município de São Paulo SP. A confirmação do diagnóstico da osteoporose foi estabelecida mediante verificação dos relatórios da densitometria de antebraço obtidos, e comparados aos diagnósticos obtidos nas radiografias panorâmicas para o estabelecimento de um único índice quantitativo e qualitativo que considere a reabsorção e a baixa espessura da cortical na avaliação. O novo Índice Panorâmico Quantitativo e Quantitativo (IPQQ) foi determinado. A concordância entre as duas avaliações, calculada como razoável, reflete sensibilidade (moderada) de 56%, especificidade (satisfatória) de 82% e VPN (Valor Preditivo Negativo) de 68%. O IPQQ apresentou associação e concordância significativa com a densitometria (padrão ouro) podendo ser utilizado como teste para o rastreamento, porém cuidados ou algumas restrições deverão ser tomados em sua utilização, pois a intensidade de concordância razoável foi devida a uma moderada sensibilidade deste teste em relação ao padrão ouro. / Recently, osteoporosis has been implicated as being associated with oral manifestations represented by bone loss, especially in the jaw. However, the techniques of direct assessment of mandibular bone mineral density has not demonstrated good accuracy and precision. This study aimed to evaluate, through a descriptive and analytical study, the possibility of the use of panoramic radiographs as a method to express the morphological changes of the jaw due to age and to establish a single index quantitatively and qualitatively, to identify cases of osteopenia and osteoporosis. The research period occurred in women in menopause and postmenopause in dental treatment in dental clinics of the Faculty of Dentistry, University of São Paulo, in São Paulo - SP. Confirmation of the diagnosis of osteoporosis was established by scanning densitometry reports obtained from the forearm, and compared the diagnoses obtained from panoramic radiographs for the establishment of a single index that considers both quantitative and qualitative resorption and lower cortical thickness in the assessment. The new Quantitative and Quantitative Panoramic Index (QQPI) was determined. The agreement between the two assessments, calculated as reasonable, reflects sensitivity (moderate) 56%, specificity (satisfactory) to 82% and NPV (Negative Predictive Value) of 68%. The QQPI showed significant association and agreement with densitometry (gold standard) can be used as a test for the screening, but some restrictions or care should be taken into use, because the intensity of reasonable agreement was due to a moderate sensitivity of this test in compared to the gold standard.
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Avaliação da densidade mineral óssea por meio da radiografia panorâmica: modificadores e determinantes no resultado / Evaluation of bone mineral density by means of panoramic radiography : modifiers and determining the resultLituania Fialho de Miranda 11 December 2014 (has links)
A osteoporose tem sido apontada como grave problema de saúde pública, que compromete a qualidade de vida dos seus portadores. Um dos principais fatores que influencia na prevenção à fraturas provenientes dessa enfermidade é o diagnóstico precoce. O diagnóstico das alterações morfológicas da mandíbula por meio de radiografias panorâmicas (RP) é um método barato, simples e indicado para o rastreamento da desmineralização óssea que mostrou estar associado às alterações sistêmicas. O presente estudo descritivo-analítico objetivou avaliar se existem e quais são as variáveis que podem interferir na determinação do diagnóstico por meio das RPs. Foram analisados dados sócio-biológicos, radiografias panorâmicas e densitometrias ósseas (DO) de um total de 435 pacientes. A análise das RPs foi realizada por meio do Índice Panorâmico Quantitativo e Qualitativo (IPQQ), estabelecido em outra parte desta pesquisa. Essas observações foram então relacionadas aos resultados da DO e às variáveis coletadas no questionário de dados sócio-biológicos. A análise das RPs mostrou estar correlacionada com a DO (kappa = 0,7) e mostrou ainda que pode ser influenciada pelo uso de bisfosfonatos ( p = 0,0137), renda ( p = 0,0264), e perda dentária representada pelas variáveis uso de prótese parcial removível ( p = 0,0249) e prótese parcial fixa ( p = 0,0320). O presente estudo propõe ainda outras investigações conduzidas com desenhos mais rigorosos, para compreensão do problema que ainda guarda muitas lacunas. / Osteoporosis has been identified as a serious public health problem affecting patients\' life quality. One of the major factors that influences fractures prevention from this disease is early diagnosis. The diagnosis of mandible morphological changes using panoramic radiographs (PR) is an inexpensive, simple method suitable for screening bone demineralization associated with systemic changes. This descriptive- analytical study aimed to evaluate whether there are and what are the variables that can interfere in the determination of PRs\' diagnosis. Socio-biological data, PR and bone densitometry (BO) of 435 patients were analyzed. The analysis was performed by RPs\' Quantitative and Qualitative Panoramic Index (QQPI) previously established in another part of this research. These observations were then related to BO results and variables collected from socio-biological data questionnaire. The PR analysis were correlated with BO (kappa = 0.7) and could be influenced by the use of bisphosphonates (p = 0.0137), income (p = 0.0264), and tooth loss, represented by the variables: use of removable partial dentures (p = 0.0249) and use of fixed partial denture (p = 0.0320). This study also suggests the conduction of more rigorous designs researches to understand this problem that still has many gaps.
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Effect of Short-Term Estrogen Depletion on Compact Bone Microdensitometry in the EweBugbee, Cailyn 01 December 2012 (has links)
Osteoporosis affects the human skeleton through the direct effects of the disease on the function and structure of bone. Individuals who are affected by osteoporosis may be subject to serious fractures and it is estimated that annually approximately 1.5 million fractures can be attributed to this disease [1]. The disease is categorized as the direct side effect of increased bone porosity and bone loss and is directly linked to estrogen deprivation [2]. Animal models are often used to make initial conclusions about the effects of the disease or pharmacological treatments. In this study, sheep were chosen as a representative animal model due to their similar metabolic characteristics to that of a human. Like most animals, the ovine does not undergo a natural menopause and an ovariectomy was necessary to replicate the condition. The study objective was to quantify compact bone density present in ovine at three months post ovariectomy.
The study included 112 ovine separated into different treatment groups. The treatment groups were separated into 4 groups of 28 based on season of surgery: autumn, winter, spring, and summer. Each seasonal group was further divided into 2 groups of 14; the first group underwent an ovariectomy; and the second group underwent a sham surgery, in which the ovaries were visualized and handled but left in the abdomen. One group was sacrificed 3 months post operatively and the other group was sacrificed at 12 months post operatively. This study specifically looks at ewe sacrificed at 3 months. The radius from each sheep was cut into the anatomical sectors: cranial, caudal, craniolateral, craniomedial, caudomedial, and caudolateral. Each anatomical sector was turned into a microradiograph for analysis. Densitometry was performed to determine the density of each specimen using the estimated thickness of aluminum (ETA) as the key. Statistical analysis assessed the resulting data to understand the effects of treatment, season of sacrifice, season of surgery, and anatomical sector by comparing both mean ETA and standard deviation ETA to understand changes in bone density.
The results revealed significant differences between the ovariectomy and sham groups as well as variation within season of surgery and season of sacrifice in both groups. Anatomical sector showed no significant variation. The differences in the thickness of aluminum seen in the sheep that underwent a sham operation can be attributed to the presence of estrogen. The sheep that underwent an ovariectomy showed differences in the estimated thickness of aluminum that can be attributed to other seasonal characteristics including the influence of Vitamin D. The results and conclusions within this study can be used to influence bone material characteristics and bone loss test protocols in future osteoporosis and estrogen depletion studies.
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