Intermittent administration of parathyroid hormone improves the repairing process of rat calvaria defects: A histomorphometric and radiodensitometric study.

BACKGROUND: The aim of this study was to evaluate the effects of intermittent treatment of parathyroid hormone (PTH (1-34)) on the bone regeneration of critically-sized rat calvarial bone defects. MATERIAL AND METHODS: Thirty-two male rats were trephined (4mm full-thickness diameter), in the central part of the parietal bones and divided into 2 groups of 16. The PTH group received subcutaneous injections of PTH (1-34) at 40µg/kg, 3 times a week and the control (CTL) group received the vehicle in the same regimen. The rats were sacrificed at 4 weeks post-treatment regimen, the parietal bones were extracted and samples were evaluated through histomorphometry and radiodensitometry. RESULTS: The histological observations showed that the PTH group presented more "island-like" new bone between the defect margins with fibrous tissues than did the CTL group. The PTH group significantly exhibited greater histologic bone formation than did the CTL group (1.5mm ±0.7; 1.9 mm ± 0.6, p<0.05/ for residual bone defect). The radiodensitometry analysis revealed significant differences among the PTH and CTL groups (2.1 Al eq. ±0.04; 1.8Al eq. ±0.06, p<0.05), demonstrating an increase in bone mineral density. The PTH treatment contributed to the bone formation with a higher amount of mineral and/or fibrous tissue when compared with the CTL group. CONCLUSIONS: The results suggest that it was possible to increase the process of bone regeneration by accelerating the healing process in rat calvarial defects through intermittent administration of the PTH treatment.

Estudo comparativo entre os drenos de borracha e tubular na drenagem de abscessos dentários / Comparative study between rubber and pipe drains used in dental abscesses

Os abscessos de origem dentária apresentam relaçäo com a microbiota que se altera com o grau de saúde bucal. Reconhecendo a necessidade de se estabelecer condutas conservadoras, a eliminaçäo destes focos de infecçäo deve ser a mais precoce. A manipulaçäo do sítio da infecçäo através das manobras de drenagem e eliminaçäo da causa permite o controle das infecçöes odontogênicas. No presente estudo foram analisadas as alteraçöes relacionadas a sintomatologia dolorosa e temperatura nos períodos de 0, 24 e 48 horas, quando da utilizaçäo do dreno de polietileno modificado e dique de borracha nos processos de drenagem de abscessos dentais localizados intra-bucais em 29 pacientes adultos. Os resultados permitiram concluir que näo houve diferenças estatísticas entre as drenagens com dreno de dique de borracha (Grupo I) e do tubo de polietileno (Grupo II); as médias de dor no período 48 horas em ambos os grupos foram menores, significando uma grande reduçäo na sintomatologia dolorosa, o que caracterizou eficácia de drenagem em ambas as técnicas