Aims: Rough-surfaced dental implants are considered optimum surfaces for osseointegration, but have a high incidence of peri-implantitis. In contrast, machined surface dental implants do not cause peri-implantitis, but enable less osteoblast proliferation and differentiation, which is important in bone forming around the implant. We previously found that synthetic bone mineral(SBM)developed for osteoporosis, accelerates bone forming around rough-surfaced implants in rats. However, the effect of SBM has not been investigated in normal rats without implants. Thus, this study investigated whether SBM is influence in eliciting bone forming in normal rats without implants.

Methods: twenty-four female Wistar normal rats (7 weeks of age) were randomly assigned to receive a control group fed a diet without SBM (n = 12, control) or an experimental group fed a diet with SBM(n=12, experimental). The rats were sacrificed at

11 and 13 weeks. Bone mineral density(BMD)and fluorescent staining were assessed at the distal end of the femur. Between-group differences in BMD at 11 and 13 weeks of age were analyzed.

Results: BMD in cortical bone and cancellous bone was significantly higher in rats who received SBM than those who did not at both 11 and 13 weeks of age. Fluorescence microscopy image of rats who received SBM demonstrated more green fluorescence,compared with rats who did not receive SBM, at both 11 and 13 weeks of age.

Conclusions: Rats who received SBM exhibited increased BMD relative to rats who did not receive SBM, which indicated that the intake of SBM was effective in bone forming.