ABSTRACT
El objetivo de este estudio fue evaluar el efecto de la deficiencia de estrógenos asociada con dieta hiperlipídica sobre la integridad de la mandíbula de ratas. Para este experimento se selecionaron Ratas Wistar fueron divididas en 4 grupos: Control (C4%), Control hiperlipídica19% (C19%), ovariectomizadas 4% (OVX4%) y Ovariectomizada 19% (OVX19%). El experimento empezó con la castración (90 días), seguida de dieta hiperlipídica durante 30 días. Al fin, la sangre fue recogida para el análisis de los niveles séricos de calcio, fósforo, fosfatasa alcalina y estradiol. El fósforo disminuyó cuando hay aumento de la fosfatasa alcalina en todos los grupos en comparación con el C4%. En las vértebras L4, los pesos inmersos y húmedos aumentarán con la castración y la dieta hiperlipídica, mientras que el porcentaje de materia orgánica y minerales disminuyeron. En las mandíbulas, los pesos inmersos, húmedos y la densidad ósea aumentaran con la castración, pero disminuyeron con la combinación de castración / dieta. En las cenizas de las mandíbulas, el porcentaje de magnesio aumentó significativamente en todos los grupos. En las pruebas biomecánicas de las vértebras L4 y fémur no se encontraron diferencias significativas entre los grupos. Sin embargo, los grupos alimentados con dieta hiperlipídica tuvieron una menor resistencia a la tensión aplicada en la mandíbula. Dentro de las limitaciones del estudio, se puede notar que en estas ratas, la deficiencia de esteroides sexuales asociada con la dieta hiperlipídica influye negativamente sobre la integridad del hueso mandibular...
The aim of this study was to evaluate the effect of estrogen deficiency associated with a high fat diet on bone integrity of the jaw of rats. The pregnant rats were evaluated by vaginal cytology were 90 days old, divided into four groups: Control (C4%), Control hiperlipídica19% (C19%), ovariectomized 4% (OVX4%) and Ovariectomized19% (OVX19%). The experiment began with castration (90 days), followed by feeding with a high fat diet for 30 days. At the end, blood was collected. Jaws, vertebrae L4 and femur were removed and prepared for analysis. There were no differences in food intake, the body length or in bone measurements. Serum calcium decreased in the castrated groups. The level of phosphorus decreased and alkaline phosphatase increased in all groups. Some differences were observed among physical parameters. L4 vertebrae, immersed and wet weights increased with castration and the high fat diet, while the percentage of organic material and mineral decreased. In the jaws, immersed and wet weights and bone density increased with castration, but decreased with the combination spaying/fat diet. Bone volume and percentage of water decreased with intake of high fat diet. In the ashes of the jaws percentages of magnesium were increased in all groups, without changes in calcium and phosphorus. Groups fed with high-fat diets had lower resistance to the applied voltage in the jaw. It was demonstrated in these rats that, the deficiency of sex steroids associated with a high fat diet negatively influences mandibular bone integrity...
Subject(s)
Animals , Mice , Estrogen Antagonists/chemistry , Diet, High-Fat , Hyperlipidemias/chemically induced , Alkaline Phosphatase , Bone Density , Mandible , PhosphorusABSTRACT
BACKGROUND:The traditional surgical method have large trauma in the treatment of tibiofibular syndesmosis injury, and cannot wel complete the repair of ligament. But the suture anchor has clear effect for ligament repair, ligament reconstruction and bone connection. OBJECTIVE:To investigate the biomechanical properties of the suture anchor in the treatment of tibiofibular syndesmotic injury, and to compare with lag screw internal fixation. METHODS:Eight ankle joint specimens were col ected, and the biomechanical experiment was performed for stress analysis. The suture anchor technology and lag screw internal fixation were used respectively to treat the tibiofibular syndesmotic injury. The biomechanical properties of the stress strength, stiffness and stability were compared. RESULTS AND CONCLUSION:The biomechanical properties of the stress strength, stiffness and stability of suture anchor technology for the treatment of tibiofibular syndesmotic injury were better than those of lag screw internal fixation, and there were significant differences in the strength and stiffness between two methods (P<0.05);the stress shielding rate of suture anchor technology was lower than that of lag screw internal fixation, and the difference was significant (P<0.05);the tibiofibular syndesmosis separated displacement of suture anchor technology was lower than that of lag screw internal fixation, and the difference was significant (P<0.05). The results indicate that the suture anchor technology is a minimal invasion and good method to realize physiological reconstruction and elastic fixation with stable fixation strength and less trauma, and without secondary operation.
ABSTRACT
Objetivos: Analisar a resistência mecânica de 13 tipos de cimentos ósseos acrílicos comercializados em nosso país, testando suas propriedades físicas de resistência às forças de tração e de flexão e comparar a resistência dos cimentos ósseos sem antibiótico com seus similares com antibiótico. Método: Foram confeccionados corpos de prova de acordo com a norma regulamentadora vigente (ISO 5833 e ISO 527), utilizando os parâmetros Weibull, onde, para se obter resultados dentro do limite mínimo de erro aceitável de 5%, o número de espécimes testados deve ser de 7 a 11 corpos de provas. Foram selecionamos nove corpos de prova para cada marca. Os testes de tração e de flexão foram realizados no Departamento de Materiais da Faculdade de Odontologia da Universidade de São Paulo - SP com a máquina de ensaio universal Riehle modelo Fs-5, com capacidade de 2.400 kg e com velocidade de 0,02 a 2 polegadas/segundo. Foram anotadas a força (MPa) no momento de fratura dos nove corpos de prova para cada cimento, assim como a média e desvio padrão para o teste de tração e flexão. O estudo estatístico foi realizado pelo teste de contraste de Tukey e pelo teste da análise de variância comparando-se as médias das amostras de cada cimento utilizado. Resultados: Observamos diferença significante entre as amostras selecionadas neste trabalho e diminuição significante na resistência mecânica das amostras que continham antibiótico na sua fórmula original em comparação com seus similares sem antibiótico. Conclusões: Os cimentos ósseos apresentaram diferenças significantes quanto à resistência mecânica à tração e à flexão. A presença de antibiótico na composição original dos cimentos ósseos diminuiu significantemente a resistência mecânica nos testes de tração e flexão.