M Nasu1, Y Amano, A Kurita, T Yosue. 1. Dental Research Institute, Nippon Dental University, School of Dentistry, Tokyo, Japan.
Abstract
OBJECTIVE: The purpose of the present study was to investigate osseointegration using radiographs of titanium (Ti) implants into the osteoporotic mandible of rats. MATERIALS AND METHODS: Rats were divided into three groups: first group, which were fed a standard diet throughout (control group), second group which were fed a Ca-deficient diet for only 1 week before implantation (group A), and those which were fed the Ca-deficient diet before and after implantation (group B). On the 7th and 42nd days after implantation, bone changes in those rats were examined by microradiographs and autoradiographs. RESULTS: On the 7th day after implantation, calcification of newly formed bones was lower in groups A and B than in the control group, 45Ca uptake was seen in surrounding bones adjacent to the implant, as well as throughout the mandible. On the 42nd day after implantation, trabecular bone in group A showed radiopacity as seen in the control group. In the alveolar crest and peri-implanted bones in group B, thin bone formation with active 45Ca incorporation was found. CONCLUSIONS: It is suggested that irrespective of the calcium deficiency status in rats, trabecular bones around the implant are restored to a healthy state to some extent by resuming an intake of a necessary amount of dietary calcium. In continued calcium deficiency, osseointegration with the implant and alveolar bone was still observed as in the healthy rats suggesting calcium deficiency is not always a factor to regulate osseointegration of mandibular endosseous implants.
OBJECTIVE: The purpose of the present study was to investigate osseointegration using radiographs of titanium (Ti) implants into the osteoporotic mandible of rats. MATERIALS AND METHODS:Rats were divided into three groups: first group, which were fed a standard diet throughout (control group), second group which were fed a Ca-deficient diet for only 1 week before implantation (group A), and those which were fed the Ca-deficient diet before and after implantation (group B). On the 7th and 42nd days after implantation, bone changes in those rats were examined by microradiographs and autoradiographs. RESULTS: On the 7th day after implantation, calcification of newly formed bones was lower in groups A and B than in the control group, 45Ca uptake was seen in surrounding bones adjacent to the implant, as well as throughout the mandible. On the 42nd day after implantation, trabecular bone in group A showed radiopacity as seen in the control group. In the alveolar crest and peri-implanted bones in group B, thin bone formation with active 45Ca incorporation was found. CONCLUSIONS: It is suggested that irrespective of the calcium deficiency status in rats, trabecular bones around the implant are restored to a healthy state to some extent by resuming an intake of a necessary amount of dietary calcium. In continued calcium deficiency, osseointegration with the implant and alveolar bone was still observed as in the healthy rats suggesting calcium deficiency is not always a factor to regulate osseointegration of mandibular endosseous implants.