PURPOSE

To determine the efficacy of an alloplastic graft material, consisting of a pure-phase beta-tricalcium phosphate (beta-TCP), in the preservation of ridge volume after tooth extraction and before dental implant placement. Histomorphometric analysis was completed on a few samples to determine the percentage of vital bone over a fixed healing period.

MATERIALS AND METHODS

Patients requiring tooth extraction and bone regeneration before implant placement were included in this study. Measurements of alveolar width were made at the time of extraction and the time of implant placement. The extraction sites were grafted with a pure-phase beta-TCP and covered with a barrier. Approximately 6 months after surgery, the sites were reentered for implant placement. Cores were taken of the regenerated material for histologic analysis, with a trephine used as the first bur in preparation for some of the osteotomies. Implants were placed according to the manufacturers' recommendations and loaded at the appropriate time.

RESULTS

The beta-TCP placed at the time of grafting extraction sockets was well tolerated in all sites with all of the barriers used. There were no incidences of postoperative infection or graft rejection. At the time of implant placement, much of the graft material had resorbed and been converted to vital alveolar bone. The implant recipient sites were dense and supported placement of endosseous dental implants that were fully stable. The width of the extraction sockets was preserved to 91% of the preoperative width.

CONCLUSIONS

Extraction socket grafting with the pure-phase beta-TCP tested in this study and covered with either a resorbable collagen or dense polytetrafluoroethylene barrier is a predictable method for preserving alveolar dimensions. The graft material resorbs to a high percentage in the timeframe desired between extraction and dental implant placement, as shown clinically, radiographically, and histologically. In addition, the regenerated material in the socket has enough density to support implant placement with subsequent loading in the 4- to 6-month period used in this study.