Implant Site Under-Preparation to Compensate the Remodeling of an Autologous Bone Block Graft

Autologous bone block grafting is an efficient technique to thicken an atrophied residual alveolar ridge. A variable degree of resorption, however, occurs due to graft remodeling. In this study, we hypothesize that under-preparation of implant socket would permit the dental implant to act as a bone expansor and thus compensate for the contraction in the augmented ridge width. For that reason, 10 patients received an autologous bone block graft that was obtained from the ramus of the mandible. Residual alveolar ridge width was measured on CBCT scans obtained before surgery (T0), after 2 months of healing (T1), after 4 months of healing just before implant placement (T2), and after 4 months of implant placement (T3). The thickness of the alveolar ridge was initially increased from 2.5 +/- 1.4 to 6.1 +/- 2.0 mm. Before implant insertion, this width was decreased to 5.6 +/- 2.1 mm. The last measurement after implant insertion indicated an increase to 7.3 +/- 1.8 mm. In comparison to the measurements at T1, a loss of about 0.5mmof the augmented width occurred. But, this loss was compensated by an increment of 1.2 mm at T3 (after implant insertion) if related to the measurement at T1. Neither gingival dehiscence nor block exposure was observed. Within the limitations of this study, under-preparation of implant socket could make the ridge expansion possible during implant insertion and thus to compensate the remodeling of autologous bone block graft.