Mandibular reconstruction using induced membranes with autologous cancellous bone graft and HA-betaTCP: animal model study and preliminary results in patients.

Providing an acceptable quality of life for patients after reconstruction of mandibular segmental defects is challenging because the surgical techniques available have limitations. The authors evaluated two-stage mandibular reconstruction in rabbits and provide preliminary results in humans. 21 rabbits underwent bilateral segmental mandibulectomy and the defect was filled with methylmethacrylate. The methylmethacrylate was removed after 4 weeks and an iliac autograft performed on the right-hand side and an autogenous graft with hydroxyapatite and triphasic calcium phosphate (HA-betaTCP) on the left-hand side. Four patients with severe mandibular osteoradionecrosis underwent a two-stage reconstruction. No clinical or paraclinical complications were noted. Hematoxylin-eosin-saffron staining revealed an induced membrane lining the cavity of all samples with dense vascularity. Decalcified, undecalcified and histomorphometric analysis showed new bone formation in the biomaterial and the autograft. Calcium uptake was higher inside the new cortical bone, notably at sites with HA-betaTCP. CT scans at 6 months showed that two patients had a favorable outcome with cortico-cancellous bone. Microscopic and immunochemical analysis confirmed the experimental data. This study demonstrates the feasibility of mandibular reconstruction using the induced membranes technique. This technique is efficient, and the results would be better in non-irradiated patients with good general health.