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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Nutrice a kostní denzita u pacientů Osteocentra III. interní kliniky VFN / Nutrition and Bone Density of Patients of Osteocentre, 3rd Medical Department, General Faculty Hospital in Prague.

Staroveská, Natálie January 2021 (has links)
This thesis deals with the relationship between bone quality and lifestyle factors with a focus on nutrition, tobacco use, alcohol consumption and physical activity. The theoretical part of the thesis presents general knowledge about bones, their composition, structure, bone division, growth and development of bones. The next two chapters describe the process of bone remodeling and calcium- phosphate metabolism. The work describes in detail the factors influencing the quality of bone mass, especially those that can be affected, such as the use of tobacco products, alcohol, some drugs and sufficient physical activity. A separate chapter is devoted to the influence of diet on the quality of bone mass. The most common disorders of calcium-phosphate metabolism and their treatment are described as well. The last chapter of the practical part is devoted to the examination of bone metabolism. The aim of the practical part of the diploma thesis was to examine the eating habits and other components of the lifestyle (smoking, physical activity, etc.) of patients of Osteocentre, 3rd Medical Department, General Faculty Hospital in Prague and to find out how these components correlate with the results of densitometric examination of the patients. Data collection was ensured by means of a questionnaire survey,...
52

Vitamin D Status and Bone Health Among Young Adult Women

Stone, Caroline 21 March 2018 (has links) (PDF)
Background: Osteoporosis is estimated to affect 200 million women in the world, affecting 10% of women aged 60, 20% of women aged 70, 40% of women aged 80 and 67% of women aged 90. Osteoporosis is characterized by low bone density and increases the risk for fractured bones; however, it may be prevented with modifiable factors such as supplements, diet, and physical activity. Vitamin D deficiency leads to bone mineral density loss, as Vitamin D3 is responsible for calcium absorption into the bones. Bone consolidation is believed to occur between 20 and 30 years old; thus, attaining peak bone mass is critical during pre-menopause. Methods: The relationship between vitamin D and bone mineral density has predominately been studied in postmenopausal populations. Therefore, we examined this association among 18-30 year old participants (n=271) in the cross-sectional UMass Vitamin D Status Study. The modified version of the Harvard Food Frequency Questionnaire was used to assess the average intake of vitamin D foods and supplements. Serum 25(OH)D3 concentrations were assayed from blood samples. Bone mineral content and bone area were measured by dual-energy X-ray absorptiometry scan. Bone mineral content (BMC), as measured in grams, provides a measure of bone mass. Bone area (BA), as measured in cm2, reflects a two-dimensional area, which is characterized by the periphery of a bone region. We used multivariable linear regression to model the relationship between bone mineral density and bone area with sources of vitamin D after adjusting for dietary and lifestyle factors. Results: In the present study, the mean and standard deviation of vitamin D is 372.7 IU and 285.8 IU, respectively. For vitamin D from supplements, the mean is 140.9 IU with a standard deviation of 232.3 IU. Finally, for vitamin D from food, the mean is 231.8 IU with a standard deviation of 182.0 IU. Compared to reference values of 600 IU, these data are below the recommended daily allowance. We did not observe an association between total vitamin D or vitamin D from foods sources with either BMC or BA. We also did not observe an association between serum 25-hydroxyvitamin D levels and BMC or BA. Conclusion: Future studies with larger sample sizes are warranted to validate this association among young premenopausal women.
53

Anatomical and physiological bases of bone marrow oedema-like structures in magnetic resonance imaging : an in-vitro macro- and microscopic study

Heales, Christine Jane January 2009 (has links)
Bone marrow oedema is a term used to define the appearance of regions of low signal on T1 weighted and high signal on T2 weighted fat-suppressed magnetic resonance images. The potential association between bone marrow oedema and prognosis in pathologies such as osteoarthritis is becoming increasingly recognised through clinical studies. A limited number of clinical studies have linked bone marrow oedema to altered bone density or altered bone marrow perfusion. The principal aims of this study were to investigate these findings in vitro, using the equine forelimb. The presence of bone marrow oedema within the equine forelimb was initially confirmed by undertaking magnetic resonance imaging scans. Bone samples were selected from 10 animals, 5 exhibiting the presence of bone marrow oedema-type abnormalities (BMOA) at the distal metacarpal. Raman microspectroscopy was used to determine the chemical composition of bone and projection radiography to provide a measure of bone density. Micro computed x-ray tomography was undertaken on a subset of three bone samples exhibiting BMOA. A second component of the study utilised contrast enhanced magnetic resonance imaging to enable comparison of perfusion to bone marrow with and without evidence of oedema. A saline flushing agent containing Evan’s blue was used so that subsequent sectioning of the bone would enable visualisation of the distribution of contrast agent as part of a histological examination of the oedematous region. An initial observation was that the majority of bone marrow oedema that was observed in the distal metacarpal appeared in a consistent location, namely the postero-inferior aspect of the bone, corresponding to the point of greatest load thereby suggesting a potential relationship to forces upon the joint. The principal observations were that there appears to be increased bone volume densities in those bone samples with evidence of bone marrow oedema. The Raman microspectroscopy did not demonstrate any statistically significant differences in the chemical composition of bone. Hence the overall impression is that bone marrow oedema is associated with a greater volume of bone, although of similar maturity and composition. There was limited evidence of increased perfusion (suggestive of increased vascularity and / or hyperpermeability) in those samples with bone marrow oedema. This work suggests that these particular bone marrow oedema lesions are associated with bone changes and potentially vascular changes although the aetiology is currently unclear. Further work is needed to determine the clinical significance and prognosis associated with these particular lesions, and whether these findings can be replicated for bone marrow oedema demonstrated at other anatomical locations.
54

Povezanost između različitih faktora rizika za pojavu osteoporoze i koštane mase u postmenopauznih žena / Correlation between different risk factors for the occurrence of osteoporosis in bone structure in postmenopausal women

Ilić Jana 21 September 2016 (has links)
<p>Uvod: Osteoporoza je sistemsko oboljenje skeleta koje se karakteri&scaron;e smanjenjem mase kosti i promenama u ko&scaron;tanoj strukturi, &scaron;to sve ima za posledicu povećanu sklonost ko&scaron;tanog tkiva ka prelomima. Prema preporuci Svetske zdravstvene organizacije, dijagnoza osteoporoze postavlja se ukoliko je T-score -2,5 SD i ispod te vrednosti, a normalan nalaz ako je vrednost T-score -1,0 SD i iznad te vrednosti. Danas se smatra da je zlatni standard u dijagnostici osteoporoze primena dvostruke X apsorpcione denzitometrije lumbalne kičme i kuka putem koje se dobiju vrednosti ko&scaron;tane mase Bone mineral density i T-score. Međutim, poznato je da postoje faktori rizika koji utiču na redukciju mase kosti na taj način &scaron;to smanjuju maksimum mase kosti koji se stiče do 35. godine života i / ili ubrzavaju inače normalan proces postepenog i blagog smanjenja mase kosti koji počinje posle 35. godine života i na taj način povećavaju rizik za frakture. Takođe, poznato je da neki od faktora rizika i njihova udruženost može dovesti do povećanog rizika za frakture i nezavisno od ko&scaron;tane mase i T-score. Ciljevi istraživanja : 1. Utvrditi ko&scaron;tanu masu u postmenopauznih žena primenom dvostruke X apsorpcione denzitometrije. 2. Analizirati distribuciju faktora rizika u pacijentkinja sa T-score ispod -2.5 SD u poređenju sa pacijentkinjama sa T-score iznad -1.0 SD. 3. Utvrditi odnos između statističkog prostora koji čine pojedinačni i udruženi faktori rizika (sa karakteristikama svakih od njih) i mase kosti određene denzitometrijski. Materijal i metode rada: Istraživanje je koncipirano delom kao prospektivna, a delom kao retrospektivna studija koja je sprovedena kod pacijentkinja u postmenopauznom periodu života, životne dobi od 50 do 80 godina. Nakon urađene dvostruke X apsorpcione denzitometrije lumbalne kičme i kuka ispitivane pacijentkinje su same popunjavale upitnik uz pomoć medicinske sestre ili lekara. Nakon dobijenih podataka pacijentkinje su podeljene u dve grupe: sa osteoporozom i bez osteoporoze. U grupi sa osteoporozom je bilo 270 pacijentkinja, a u grupi bez osteoporoze 250 pacijentkinja. Potom je sprovedena statistička obrada podataka. Nakon sveobuhvatne analize dobijenih rezultata istraživanja izvedeni su sledeći zaključci: 1.Ustanovljeno je da 60% postmenopauznih žena prosečne životne dobi od 67.0 &plusmn; 7.0 godina ima osteoporozu odnosno vrednost T-score &le; -2.5 SD. 2. Postoji statistička značajna povezanost između ko&scaron;tane mase i sledećih faktora rizika: pozitivna porodična anamneza na osteoporozu i frakture, telesna težina, telesna visina, ranije frakture, česti padovi i smanjenje u visini vi&scaron;e od 3 cm. 3. Analizom faktora rizika se dobijaju karakteristike osoba sa osteoporozom: pozitivna porodična anamneza na osteoporozu i frakture, manja telesna težina i telesna visina, smanjenje u visini vi&scaron;e od 3 cm, česti padovi i ranije frakture. 4. Hipertireoidizam i hiperparatireoidizam, reumatoidni artritis, primena kortikosteroidne terapije su faktori rizika koji su vi&scaron;e zastupljeni kod ispitivanih pacijentkinja sa osteoporozom. 5. Pu&scaron;enje, rana menopauza, alergija na mleko bez adekvatne supstitucije sa kalcijumom i nedovoljan boravak na suncu bez adekvatne supstitucije sa vitaminom D su faktori rizika koji su vi&scaron;e zastupljeni kod ispitivanih pacijentkinja sa osteoporozom. 6. Najveći doprinos celini daje pozitivna porodična anamneza na osteoporozu i frakture (20.99%), zatim slede telesna težina, telesna visina, Index telesne mase (19.03%), ranije frakture, česti padovi, smanjenje u visini vi&scaron;e od 3 cm (18.41%), pu&scaron;enje i nedovoljna fizička aktivnost (12.75%), alergija na mleko i nedovoljan boravak na suncu (12.14%), rana menopauza (8.72%), hipertireoidizam, hiperparatireoidizam, reumatoidni artritis (7.93%). 7. Analizom tri grupe obeležja koja daju najveći doprinos celini ustanovljeno je da pozitivna porodična anamneza na frakture (37.7%) i telesna težina (31.3%) predstavljaju major faktore rizika za osteoporozu. 8. Matematičkom obradom dolazi se do formule pomoću koje bi sa verovatnoćom od 64.0 % mogla predvideti osteoporoza, a sa verovatnoćom 73.2 % odsustvo osteoporoze, čime se između ostalog u na&scaron;em istraživanju donekle relativizuje neophodnost određivanja ko&scaron;tane mase u proceni rizika za prelome i u proceni potrebe za uvođenje antiosteoporotične terapije. Formula je +.214 O +.562 F +.202 R +.223 P +.335 S +.493 T +.057 V +.020 9. Potrebno je testirati dobijenu formulu na ispitivanim pacijentkinjama i nastaviti istraživanje na većem uzorku na faktore rizika koji nisu pokazali statističku značajnost.</p> / <p>Introduction: Osteoporosis is a systematic disease of skeleton characterized by the reduction of bone mass and changes in bone structure which result in the increased aptitude of bone tissue to fractures. According to the suggestion of the World Health Organization, the diagnosis for osteoporosis is set if the T-score is -2.5 SD and below it and the normal report if the value of T-score is -1.0 SD and above it. Nowadays, it is considered that the golden standard in osteoporosis diagnostic is the use of double X absorption densitometry of lumbal spine and hipe which provides the values of bone mass Bone mineral density as well as T-score. However, it has been known that there are risk factors whish influence the reduction of bone mass by reducing maximum bone mass gained by the age of 35 and/or by quckening, the normal process of gradual and mild reduction of bone mass starting after 35 and in that way increase the risk toward fractures. It mas also been known that some of the risk factors and their correlation may cause the increasement of the risk factor toward fractures not having the connection with the bone mass and T-score. Researchment aims: 1. Determine bone mass in postmenopausal women using double X absorption densitometry. 2. Analyse distribution of risk factors in patients whith the T-score below -2.5 SD comparing to the patients with T-score above -1.0SD. 3. Determine the relation between statistical space made by individual and associated risk factors (with the characteristics of each of them) and the bone mass specified by densitometry. Material and methods of working: Researchment is outlined partly as prospective and partly as retrospective study which was carried out in patients in postmenopausal life period, aged 50-80. After applying double X absorption densitometry of lumbal spine and hip the examined patients did the questionnaire by themselves whith the help of nurses and doctors. After obtaining the data, patients were divided into two groups: with and without osteoporosis. There were 270 patients in the group with osteoporosis and 250 of them without it. Thereafter, the statistic data processing was carried out. After the overall analysis of obtained results of researchment, following conclusions were conducted: 1. It has been determined that 60 % of postmenopausal women of average age 67.0&plusmn;7.0 have osteoporosis, in other words, their T-score is &le; -2.5 SD. 2. There is statistically important relationship between the bone mass and following risk factors: positive family anamnesis to osteoporosis and fractures, body weight, height, previos fractures, frequent falls and reduction of height for more than 3 cm. 3. Analysing the risk factors, characteristics of persons with osteoporosis have been obtained: positive family anamnesis to osteoporosis and fractures, smaller body weight and height, the reduction in height for more than 3 cm, frequent falls and previous fractures. 4. Hyperthyroidism and hyperparathyroidism, rheumatoid arthritis and the usage of corticosteroid therapy are the risk factors more incident in the examined patients with osteoporosis. 5. Smoking, early menopause, allergy to milk with no adequate substitution of calcium and insufficient exposition to sun rays with no adequate substitution of vitamine D are the risk factors more incident in patients with osteoporosis. 6. The largest contribution to the total makes positive family anamnesis to osteoporosis and fractures (20.99%), followed by body weight, height, Body mass index (19.03%), previos fractures, frequent falls and reduction in height for more than 3 cm (18.41%), smoking and insufficient physical activity (12.75%), allergy to milk and insufficient exposition to the sun (12.14%), early menopause (8.72%), hyperthyroidism and hyperparathyroidism, rheumatoid arthritis (7.93%). 7. By the analysis of all three goups of features giving the largest cintribution to the total, it has been determined that positive family anamnesis to fractures (37.7%), and body weight (31.3%), present the major risk factors for osteoporosis. 8. By mathematical processing we obtain the formula which can with the probability of 64.0% predict osteoporosis, and with the probability of 73.2% the absence of osteoporosis, which can, among other things in our research to some extent, require relative necessity for introduction of antiosteoporotic therapy. The formula is +.214 O +.562 F +.202 R +.223 P +.335 S +.493 T +.057 V +.020. 9. It is necessary to test the formula obtained in examined patients and continue the reseachment, on larger sample, of risk factors which have not shown statistic importance.</p>
55

Efeito do extrato hidrossolúvel de soja ou castanha-do-Brasil em ratos idosos /

Cabral, Bruna Raniel Vieira Pinto January 2019 (has links)
Orientador: Guilherme de Paula Nogueira / Resumo: O objetivo foi analisar os efeitos da suplementação do extrato hidrossolúvel de soja (EHS) ou castanha-do-Brasil nos fêmures de ratos Wistar idosos. Foram utilizados 27 ratos, com 570 dias, distribuídos em 3 grupos: grupo controle (C) (n=8) recebeu dieta padrão; grupo suplementado com extrato hidrossolúvel de soja (S) (n=9) (300 mL/dia); grupo (B) (n=10), oferecida 1 unidade de castanha-do-Brasil (±3,7g) por animal/dia. O experimento teve duração de 30 dias e ao final os ratos foram eutanasiados com 600 dias de idade. Foram analisadas: a massa corporal semanalmente (g), a ingestão de ração (g) e de água (mL) diariamente, foram feitas análises biofísicas, bioquímicas e hormonais das amostras (sangue, fêmur, gordura visceral, testículos e glândulas sexuais acessórias) colhidas no pós-morte. Os animais do grupo S e B consumiram menos ração quando comparados com o C. O grupo S consumiu menos água em relação ao controle. Em relação as concentrações dos hormônios (insulina, leptina, LH, testosterona) entre os grupos, estes não apresentaram diferença estatística significativa. Não houve diferença na densitometria e microtomografia óssea, mas a região da cabeça do fêmur dos ratos do grupo B apresentaram maior resistência (p=0,04) (B 151±15N, C 112±37N, S 137±37N). Os fêmures do grupo controle possuíram menor concentração de fosforo (p=0,03; 15±1%) comparados com os do S 16±1% e B 16±1%. Conclui-se que a ingestão de EHS não interferiu no metabolismo ósseo, mas o consumo da castanha-do... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective was to analyze the effects of soybean or Brazil nut supplementation on the femurs of elderly Wistar rats. Twenty-seven rats with 570 days of age were used, distributed in 3 groups: control group (n=8, C) with standard diet; group S (n=9) supplemented with soy milk (300 mL/day); group B (n=10), added 1 unit of Brazil nut (± 3.7g) per animal/day. The experiment lasted for 30 days, and at the end, the rats were euthanized with 600 days of age. Were measured: body mass weekly (g); feed intake (g) and water intake (mL) daily, as well as biophysical, biochemical and hormonal analysis of postmortem samples (blood, femur, visceral fat, testicles and sexual accessories glands) were analyzed. The animals of group S and B consumed less ration when compared to group C. The group S ingested less water compared to the control. Regarding the applications of hormone concentrations (insulin, leptin, LH, testosterone) between groups, these are not relevant. There were no differences on bone densitometry and microtomography but femoral head from the group B rats presented greater shear resistance (p = 0.04; B 151 ± 15N, C 112 ± 37N, S 137 ± 37N) than the other groups. Bones from control rats had lower phosphorus concentration (p=0.03; 15±1%) compared to S 16±1% and B 16±1%. It was possible to concluded that soy milk intake did not interfere on the bone metabolism, but the Brasil nut consumption resulted in greater bone strength and phosphorus concentration on the femoral head and ... (Complete abstract click electronic access below) / Mestre
56

Avaliação da neoformação óssea após instalação de malhas de titânio e enxerto ósseo - análise histológica e microtomográfica in vivo em ratos / Evaluation of bone neoformation after installation of titanium mesh and bone graft - histological and microtomographic analysis in vivo

Borges, Cristine D\'Almeida 22 August 2018 (has links)
Técnicas para reconstruções ósseas são descritas em artigos científicos e dentre as barreiras mecânicas utilizadas, a malha de titânio vem demonstrando possibilidades de tratamento para ganho ósseo. Estudos pré-clínicos são escassos na literatura relatando a melhor morfologia de malha de titânio a ser utilizada, além da necessidade de uso de membrana oclusiva adicional. Dessa forma, o objetivo do estudo é avaliar se há diferença na qualidade e volume ósseo formado ao utilizar malhas de titânio com diferentes diâmetros de poro, e avaliar a necessidade de utilização de uma membrana adicional, sobre a malha de titânio. Para este estudo foram utilizados 28 ratos adultos machos do tipo Wistar, com peso médio de 410,8 gramas. Os animais foram divididos aleatoriamente em quatro grupos experimentais principais: Grupo P300: uso de malhas de titânio Painel Grade 15 Neodent®, com espessura de 0,3 mm e perfuração medindo 3 mm entre os vértices (n = 7); Grupo P175: uso de malhas de titânio Painel Grade 20 Neodent®, com espessura de 0,3 mm e perfuração com 1,75 mm diâmetro (n = 7); Grupo P85: uso de malhas de titânio Bionnovation® Surgitime Titânio, com espessura de 0,04 mm e perfuração com 0,85 mm de diâmetro (n = 7); Grupo P15: uso de malhas de titânio Bionnovation® Surgitime Titânio de espessura de 0,04 mm e perfuração com 0,15 mm de diâmetro (n = 7). Em todos os grupos, cada fêmur foi subdividido em teste (fêmur em que foi utilizado Bio-Oss Collagen® e membrana de colágeno BioGide®) e controle (apenas Bio-Oss Collagen®). Após 24 horas do procedimento cirúrgico, o qual foi realizado com anestesia geral, os animais foram submetidos a análise de microtomografia computadorizada in vivo, também sob anestesia. Após 30 dias, foram novamente submetidos a microtomografia computadorizada in vivo e, em seguida, eutanasiados para processamento histológico. Após análise estatística, foi observado que não houveram diferenças estatísticas em relação aos parâmetros volumétricos, nas comparações intra e entre grupos. Em relação a densidade mineral óssea, nas comparações intra grupos, relacionando fêmur teste e controle, não foram observadas significâncias estatísticas. Nas comparações entre grupos, foram observadas maior densidade nos grupos com maior diâmetro de perfuração (p<0,05). Nas análises histológicas, foi possível observar neoformação óssea do tipo esponjosa, demonstrando o mesmo padrão em todos os grupos, com presença de osteócitos em lacuna, início de um processo de amadurecimento ósseo com formação de lamelas concêntricas e íntima relação do novo osso formado pelo enxerto e o fêmur. De acordo com os resultados pode-se concluir que, o diâmetro do poro da malha de diâmetro pode interferir na qualidade óssea, porém, irá depender do enxerto ósseo utilizado, e o uso adicional de membrana de colágeno, quando associada a enxerto ósseo, não determinou a formação de novo osso de qualidade superior / Techniques for bone reconstruction are described in scientific articles and, among mechanical barriers used, titanium mesh has been showing possibilities of treatment for bone gain. Preclinical studies are scarce in the literature reporting the best morphology of titanium mesh to be used, in addition to the need for additional occlusive membrane. Thus, the objective of this study is to evaluate if there is a difference in bone quality and volume formed when using titanium meshes with different pore diameters, and to evaluate the need to use an additional membrane on the titanium mesh. For this study, 28 male Wistar male rats with an average weight of 410.8 grams were used. The animals were randomly divided into four main experimental groups: Group P300: use of titanium meshes Grid Panel 15 Neodent®, with thickness of 0.3 mm and perforation measuring 3 mm between vertices (n = 7); Group P175: use of titanium meshes Grid Panel 20 Neodent®, with thickness of 0.3 mm and perforation with 1.75 mm diameter (n = 7); Group P85: use of titanium meshes Bionnovation® Surgitime Titanium, 0.04 mm thick and 0.85 mm diameter (n = 7); Group P15: use of titanium meshes Bionnovation® Surgitime Titanium thickness 0.04 mm and perforation with 0.15 mm diameter (n = 7). In all groups, each femur was subdivided into test (femur in which Bio-Oss Collagen® and BioGide® collagen membrane was used) and control (Bio-Oss Collagen® only). After 24 hours of the surgical procedure, which was performed under general anesthesia, the animals were submitted to in vivo microtomography, also under anesthesia. After 30 days, they were again submitted to computerized in vivo microtomography and then euthanized for histological processing. After statistical analysis, it was observed that there were no statistical differences in relation to the volumetric parameters, in intra and inter group comparisons. Regarding bone mineral density, in intragroup comparisons, relating femur test and control, no statistical significance was observed. In the comparisons between groups, higher densities were observed in the groups with greater drilling diameter (p <0.05). In the histological analyzes, it was possible to observe new bone formation of the spongy type, showing the same pattern in all groups, with presence of osteocytes in the gap, beginning of a bone ripening process with concentric lamella formation and an intimate relation of the new bone formed by the graft and the femur. According to the results, it can be concluded that the pore diameter of the diameter mesh may interfere with bone quality, however, it will depend on the bone graft used, and the additional use of collagen membrane, when associated with a bone graft, does not determined the formation of new bone of superior quality
57

Uso de alendronato de sódio em ratas submetidas à imobilização gessada. Análise de propriedades mecânicas do fêmur e da densidade óssea radiográfica do colo femoral / Use of the sodium alendronate in rats submitted to plaster cast immobilization. Analysis of the mechanical properties of the femur and of the femoral neck radiographic density.

Cecim, Paulo Eugenio Santos 03 October 2007 (has links)
A imobilização prolongada do aparelho locomotor, embora usada com finalidades terapêuticas, leva à osteopenia, o que causa enfraquecimento ósseo. Foi investigado se o uso concomitante do alendronato de sódio (um inibidor da atividade osteoclástica) é capaz de diminuir ou prevenir o enfraquecimento ósseo causado pela imobilização. Ratas fêmeas Wistar, adulta-jovens foram distribuídas em seis grupos: não imobilizado e sem tratamento (controle); não imobilizado + alendronato diário (0,1 mg/kg); não imobilizado + alendronato semanal (0,7 mg/kg); imobilizado e sem tratamento; imobilizado + alendronato diário (0,1 mg/kg); imobilizado + alendronato semanal (0,7 mg/kg). A imobilização foi obtida com aparelho gessado na região lombar, pélvica e de todo o membro pélvico direito (exceto a pata). O período de observação, imobilização e tratamento foi de 28 dias. Os métodos de avaliação foram a determinação da massa corporal, da massa e comprimento do fêmur direito, o ensaio mecânico em flexo-compressão no terço proximal do fêmur e a densidade óssea radiográfica do colo do fêmur direito. A comparação foi intergrupos. A imobilização, com alendronato ou não, causou diminuição significativa na massa corporal, enquanto que para a massa do fêmur ela diminuiu significativamente para os animais apenas imobilizados e não tratados. Com respeito à análise mecânica, houve sensível diminuição da força máxima e da rigidez nos animais apenas imobilizados. Os animais não imobilizados e que receberam alendronato de sódio (diário ou semanal) apresentaram maior resistência óssea, mesmo em relação ao controle não imobilizado e não tratado. Para os animais imobilizados e tratados (com alendronato de sódio diário ou semanal) houve aumento da força máxima e da rigidez que se igualaram ou mesmo ultrapassaram os valores do controle não imobilizado e não tratado. A determinação da densidade óssea correspondeu aos achados nos ensaios mecânicos de tal forma que a correlação dela com a força máxima e com a rigidez foi positiva e linear. Foi concluído que a imobilização gessada causou acentuado enfraquecimento ósseo que foi prevenido eficientemente pelo uso do alendronato de sódio, tanto de aplicação diária ou semanal, caracterizados pelo aumento da força máxima e rigidez no ensaio de flexo-compressão, bem como aumento da densidade óssea radiográfica. / Prolonged immobilization of the skeletal system has been used as an invaluable tool in the treatment of several orthopaedic conditions. However, as a side effect, it causes osteopenia and bone weakening. In this research it was investigated if the concomitant administration of sodium alendronate (a potent inhibitor of the osteoclastic activity) can prevent the bone weakening caused by immobilization. Young-adult female Wistar rats were distributed into six groups: non-immobilized and non-treated (control); non-immobilized + daily alendronate (0.1 mg/kg); non-immobilized + weekly alendronate (0.7 mg/kg); immobilized (no treatment); immobilized + daily alendronate (0.1 mg/kg); immobilized + weekly alendronate (0.7 mg/kg). Immobilization was achieved with a spica cast with inclusion of the right hindlimb. The period of pharmacological treatment and immobilization was 28 days. The evaluation consisted in the determination of the body mass, femoral mass, femur length, bending compression test of the proximal third of the femur and radiographic densitometry of the femoral neck. Inter-group evaluation was made. Immobilization with or without alendronate caused a significant decrease in the body mass. Conversely, the femur body mass significantly decreased in the immobilized in non-treated animals only. The mechanical tests showed that there was a significant reduction of the ultimate strength and stiffness for the immobilized and non-treated rats. When the animals were immobilized and received sodium alendronate (either daily or weekly) the femurs were stronger even in comparison in with the non-treated and non-immobilized animals (control). The immobilized and alendronate treated animals (both schedules) displayed an increased stiffness and ultimate strength that were equal or even surpassed the non-treated controls. Bone density followed the mechanical results and relationship of such parameters showed a positive linear correlation. We concluded that the plaster cast immobilization caused a significant bone weakening that was efficiently prevented either by the daily or by the weekly subcutaneous administration of sodium alendronate. This was characterized by the increase of the ultimate strength and stiffness from bending compression tests as well as by the enhancement of the radiographic bone density.
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Biologia da movimentação dentária induzida e das reabsorções radiculares associadas: influência do gênero e dos bisfosfonatos / Biology of induced tooth movement and associated root resorption: the influence of the gender and bisphosphonates

Santamaria Junior, Milton 21 May 2009 (has links)
O presente trabalho discutiu os mecanismos biológicos envolvidos na movimentação dentária induzida e as possíveis consequências deste procedimento, essencial para o tratamento ortodôntico. O estudo do movimento dentário induzido em animais tem como objetivo compreender as reações dos tecidos envolvidos e analisar as variáveis que podem interferir na mecânica ortodôntica aplicada. Assim, pode-se prevenir o efeito mais indesejado de um tratamento ortodôntico: a reabsorção dentária associada. Histomorfometricamente analisou-se a influência do gênero na movimentação dentária em ratos da linhagem Wistar, nos períodos de 3, 5, 7 e 9 dias de movimentação, quando se concluiu que não houve diferença estatisticamente significante na frequência e nas dimensões das reabsorções radiculares entre os gêneros nos diferentes períodos experimentais analisados (p&#8804;0,05). Fatores externos também podem influenciar nas reações teciduais frente à movimentação dentária induzida e na ocorrência das reabsorções radiculares. Desta forma, o estudo também analisou o efeito dos bisfosfonatos, o alendronato, na densidade óssea, já que os bisfosfonatos são reconhecidamente potentes inibidores da reabsorção óssea. Também em ratos Wistar e utilizando histomorfometria determinou-se a densidade óssea alveolar maxilar em cortes transversais na região entre as raízes do primeiro molar murino. Os resultados revelaram que não houve diferença estatisticamente significante na densidade óssea alveolar entre os animais que receberam alendronato e o grupo controle (p=0,3754). De acordo com a metodologia utilizada, pôde-se concluir que o bisfosfonato do tipo alendronato não altera morfologicamente a qualidade óssea alveolar, mantendo as características estruturais e mecânicas do tecido em animais saudáveis. Fatores como o gênero e o uso de bisfosfonatos do tipo alendronato não influenciam de forma decisiva os fenômenos biológicos da movimentação dentária. Este fato pôde ser exemplificado em um relato de caso clínico de um paciente do gênero feminino e que fez uso de alendronato. Os tratamentos ortodôntico e reabilitador foram executados sem qualquer complicação, após minucioso procedimento de anamnese, diagnóstico e plano de tratamento, podendo ser assim restabelecida a condição estética e funcional ideal para o paciente. / The work talked over the biologic mechanisms involved on induced tooth movement and the possible consequences, essential in orthodontic treatment. The tooth movement research in animals has the objective to understand the reactions of the involved tissues and analyze the variables that can interfere in the orthodontic treatment. Thus, we can avoid undesirable effects of the orthodontic treatment such as the external root resorption. The influence of the gender on tooth movement in Wistar rats was quantified by histomorphometry, at the periods of 3, 5, 7 and 9 days of tooth movement. There was no statiscally significant difference in the frequency and in the dimensions of root resorptions between the genders in the analyzed periods (p&#8804;0.05). External factors such as the use of biphosphonate, also may have some influence on the tissue reactions when induced tooth movement is applied and also on the occurrence of root resorption. Therefore, the study also aimed to evaluate the influence of the bisphosphonates (alendronate) on bone density, since the bisphosphonates are recognized as a potent inhibitor of bone resorption. Wistar rats were used to determine histomorphometricly the maxillary bone density. For this, transverse sections in the region between the roots of the first rat up molar were taken. The results showed no statistically significant difference when alveolar bone density was evaluated between the alendronate and the control group (p=0.3754). It can be concluded that the alendronate may not change alveolar bone density, probably keeping the structural and mechanic properties of the tissue in healthy rats. Within the limits of the present study, it can be concluded that gender and the use of alendronate may not influence the tissue reactions when induced tooth movement is applied. This fact could be exemplified in a clinical case of a female patient who used alendronate. The orthodontic and rehabilitation treatments have been carried out without any complication. A careful medical history, diagnosis, and treatment plan were essential and thus, the aesthetic and functional condition could be reestablished for the patient.
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Avaliação da força de inserção, remoção e resistência à fratura de mini-implantes utilizados nos tratamentos ortodônticos em diferentes regiões da maxila e mandíbula / Evaluation of insertion and removal forces and fracture strength of mini-implants used in orthodontic treatments in different regions of maxilla and jaw

Pesqueira, Eliana Ionara de Oliveira 24 June 2014 (has links)
O objetivo deste estudo foi identificar o melhor torque de inserção e remoção de mini-implantes inseridos em ossos artificiais com densidades similares às regiões anterior, mediana e posterior dos maxilares. Cento e vinte mini-implantes com desenho de dupla rosca (compactas e autoperfurantes) foram inseridos. Análises com microscopia eletrônica de varredura foram feitas antes e depois dos ensaios. Os valores de torque obtidos durante a inserção e remoção dos mini-implantes foram mensurados por um torquímetro digital. Os resultados analisados levaram a concluir que os torques de inserção e remoção eram maiores conforme aumentava a densidade óssea e a espessura da cortical. O desenho das roscas dos mini-implantes influenciou no torque de inserção. As roscas com menores passos aumentaram o valor do torque de inserção. A perfuração óssea anterior à instalação diminui o torque de inserção independente da densidade óssea. Ocorreu um aumento de torque principalmente com o aumento da densidade óssea e não necessariamente com o aumento da espessura da cortical sugerindo que a densidade óssea do osso trabecular deve ser considerada no planejamento de instalação dos mini-implantes. / The objective of this study was to identify the best insertion torque and removal of mini-implants inserted in artificial bone with densities similar to anterior, middle and posterior regions of the jaws. One hundred and twenty mini-implants with a twin crew design (compact and self-drilling) were inserted into artificial bones with densities and thickness similar to cortical and trabecular bones of the maxilla and mandible. Analysis with electron microscopy was performed before and after the tests. The torque values obtained during the insertion and removal were measured using a digital torque wrench. The analyzed results led to the conclusion that the insertion and removal torques were larger with increase in bone density and cortical thickness. The design of the threads of the mini-implants influenced the insertion torques. Threads with smaller steps increased the value of insertion torques. The anterior bone drilling installation reduces the insertion torque independent of bone density. Torque increased mainly by increasing the bone density and not necessarily with increased cortical thickness suggesting that the bone density of the trabecular bone must be taken into account con in designing and installation of mini-implants.
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Densidade mineral óssea de mulheres na pós-menopausa em diferentes sítios e avaliação do risco de fratura / Bone mineral density in postmenopausal women in different sites and fracture risk assessment

Érika Miti Yasui 23 April 2012 (has links)
O rápido envelhecimento da população brasileira cria um contexto de assistência prolongada e específica a morbidades que tendem a ampliar a duração do tratamento, as incapacidades dos indivíduos, os gastos com exames complementares, internações hospitalares e medicação. Dentro desse contexto, a osteoporose, doença intimamente relacionada com o envelhecimento, pode ter um aumento considerável nos próximos anos. Conhecer quem são os indivíduos em risco de desenvolver a doença é fundamental, uma vez que a fratura, sua mais importante conseqüência clínica, representa gastos elevados com serviços de saúde e está associada à alta taxa de morbidade e mortalidade. O exame indicado pela Organização Mundial da Saúde (OMS) como padrão-ouro para o diagnóstico da osteoporose é o exame de densitometria óssea (DXA), Devidos aos custos e acesso restrito e assim, selecionar candidatos ao exame é uma questão com importantes implicações clínicas e sócioeconômicas. O objetivo deste estudo foi avaliar a validade diagnóstica da radiografia panorâmica para identificação de mulheres na pós-menopausa com baixa massa óssea. Foram utilizados: questionário baseado nos fatores clínicos de risco para osteoporose, exame de densitometria óssea (fêmur, coluna e antebraço), radiografia panorâmica digital e o São Paulo Osteoporosis Risk Index (SAPORI). O estudo é do tipo observacional transversal. Os valores de sensibilidade e especificidade, valor preditivo positivo e negativo foram calculados. A amostra foi constituída por 88 mulheres na pós-menopausa com média de idade de 61 anos. A baixa massa óssea no quadril foi observada em 62 mulheres (70,5%), na coluna em 61(69,3%), no antebraço em 78 (88,6%) e 52 (59,1%) na mandíbula. Fratura após os 50 anos de idade foi observada em 17 mulheres (19,3%) e 37 (42%) relataram ocorrência de queda nos últimos 12 meses. A radiografia panorâmica é um instrumento válido para a identificação de mulheres na pósmenopausa com baixa densidade mineral óssea / The rapid aging of the Brazilian population creates a context of prolonged and specific assistance to morbidities that tend to increase the time of treatment, disabilities and costs related to clinical tests, hospital admissions and medication. Within this context, the osteoporosis, disease closely related to aging, can have a significant burden in the next years. Identifying people at risk to present the disease is essential, once fracture, its main clinical consequence, represents high costs related to health services and is associated to the high rate of morbidity and mortality. The bone densitometry (DXA) is recommended by the World Health Organization as the gold standard test to the osteoporosis diagnosis. Due to the costs associated and restricted access, to select candidates to the exam is an important issue, with clinical and socioeconomic implications. The objective of this study was to evaluate the diagnostic validity of the panoramic radiography to identify women with low bone density. The following were performed: questionnaire based on clinical risk factors for osteoporosis and fragility fracture, bone densitometry (hip, spine and forearm), digital panoramic radiography and the São Paulo Osteoporosis Risk Index (SAPORI). This is a cross-sectional study. The values sensitivity, specificity, positive and negative predictive values were calculated. The sample was constituted of 88 post-menopausal women with an average age of 61 years. Low bone density in the hip was observed in 62 women (70.5%), in the spine in 61 (69.3%), in the forearm in 78 (88.6%) and 52 (59.1%) in the mandible. Fracture after 50 years old was observed in 17 women (19.3%) and 37 (42%) of the sample reported fall in the last 12 months. The panoramic radiography is a valid instrument to identify postmenopausal women with low bone density

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