Avaliação de diferentes modelos experimentais para análise da regeneração óssea.

Abstract

This study was carried out to compare two preclinical models in rats (Critical sized calvaria defects and guided bone regeneration in mandibles) used to assess bone repair in grafted areas by means of histomorphometric analysis. Ten rats were used to evaluate the repair of areas grafted with deproteinized bovine bone, 5 rats were submitted to critical defects calvaria defects (5 mmØ) and 5 rats were submitted to access to the mandibular branch where a teflon-dome shaped membrane was filled with the bone substitute and place on the bone tissue. After 60 days, the animals were euthanized and the samples obtained were submitted to histomorphometric analysis, where the relative amount of bone, bone substitute and soft tissue within the grafted areas were evaluated. It was verified that there were no differences between the preclinical models tested in relation to the amount of bone tissue formation (19.93 ± 4.55% in calvaria vs. 21.00 ± 8.20% in mandible). However, it was verified a smaller amount of soft tissue (43.20 ± 10.97% vs. 57.79 ± 7.61 % - p<0.01) and a greater amount of bone substitute remnant (35.80 ± 5.52% vs. 22.28 ± 4.36% - p<0.05 ) in areas grafted on the mandible than in critical defects in calvaria. Preclinical models for analyzing bone repair in areas grafted on the mandible and critical defects in calvaria present different responses regarding the amount of soft tissue and bone substitute remnants. Keywords: Bone graft, histology, tomography