Histological Comparison of New Bone Formation Using Amnion Membrane Graft Versus Resorbable Collagen Membrane: An Animal Study

The purpose of this article was to evaluate the bone induction effects of an amnion membrane–protected graft compared with a collagen membrane–protected graft in the repair of tibial bony defects in dogs. This study was performed using the tibial bone of dogs. After the removal of periosteum, similar holes were made with a 16-mm trephine drill (38 holes in total). For the study group, 10 holes were covered by absorbable collagen and 16 holes by amniotic membrane. In the control group, 12 holes were made and covered by the overlying soft tissue. Tibial bones were exposed after 6 and 12 weeks, and the samples were harvested and histologically processed. New bone formation was evaluated by histomorphometric study. Four Iranian mixed dogs older than 1.5 years were included in this study. The new bone formation was less in the control group when compared with the collagen group (P = .863). The collagen group showed less bone formation than the amnion group (P = .194), but this difference was not significant. However, bone formation in the amnion group was significantly more than in the control group (P = .050). Using the amniotic membrane appears to accelerate bone formation in guided bone regeneration. However, further studies should investigate its clinical impact on bone healing.