Combination of allograft blocks and putty in the inlay technique: clinical and histological observations

Aim: In case of atrophic posterior mandibles, the inlay bone graft technique showed remarkable results in terms of vertical bone augmentation and the use of allografts seems to be able to accelerate graft integration and therefore implant rehabilitation. Material and Methods: This case reports clinical and histological evaluations of an the inlay augmentation procedure performed with two different forms of allograft. Two cancellous blocks were used at the sides of the grafted area in order to support the crononally-positioned bony segment, whereas putty was placed between the blocks. Three months later, a CT scan demonstrated good graft integration with sufficient bone vertical increase and density. At implants placement, bone core biopsies were taken and histologically processed. During implant placement, the block was stable with good clinical osteointegration. Histological analysis showed presence of compact bone revealing areas of demarcation between grafted bone, newly formed bone and bone regeneration areas. Results: The simultaneous use of both blocks and putty cancellous grafts increased clinical and histological outcomes. The presence of the blocks gave stability to the osteotomized bony segment assuring an adequate bony vertical increase, whereas the putty increased and accelerated the graft integration. Moreover, the bony segment was clinically stable and no bone plates were used to fix it to the basal bone. Conclusion: In this case, after only 3 months from grafting, allografts showed to be effective materials for the reconstruction of the posterior mandible with inlay technique. According to the preliminary results, this material represent a good clinical alternative to autologous and inorganic bovine bone.