Effects on bone formation in ovariectomized rats after implantation of tooth ash and plaster of Paris mixture.

PURPOSE: Our goal was to report on tooth ash and plaster of Paris mixture in bone defects in an ovariectomized rat osteoporosis model.
MATERIALS AND METHODS: Sixty rats were randomly assigned to 4 groups and each group was further divided into 3 subgroups: 4, 8, and 16 weeks after implantation. The defect was filled with different grafting conditions as follows: group 1, ovariectomy and nongraft group; group 2, ovariectomy and tooth ash-plaster graft group; group 3, nonovariectomy and nongraft group; and group 4, nonovariectomy and tooth ash-plaster graft group. Histologic sections and histomorphometric analysis of defects were obtained 4, 8, and 16 weeks after surgery.
RESULTS: For the 4-week ovariectomy group, there was significantly greater bone formation in tooth ash-plaster group compared with the nongraft group. In the nonovariectomy group, the tooth ash-plaster group also showed better bone formation than the nongraft group. However, there was no statistical significance. In both the ovariectomy and nonovariectomy groups, a significant increase in bone formation was observed according to the elapse of time. The nonovariectomy group showed increased new bone formation compared with the ovariectomy group, with the tooth ash-plaster group showing statistical significance in each subgroup (P =.048).
CONCLUSIONS: Ovariectomy acts as a negative factor in new bone formation. For a critical size bony defect, the tooth ash-plaster treatment of the osseous defect produces more stable, effective, and rapid new bone formation.