This study examined the efficacy of
YM175 [disodium dihydrogen (cycloheptylamino) methylene-1, 1-
bisphosphonate] in reducing
alveolar bone loss caused by experimental
periodontitis in beagle dogs. Thirty-six dogs were used and divided into 6 groups.
Periodontitis was induced in 30 dogs (groups 2-6) by ligating the bilateral mandibular third and fourth premolar teeth with
silk ligatures and by feeding a soft diet. Six dogs were
sham-operated (group 1). Saline (placebo),
flurbiprofen (0.02 mg/kg) and
YM175 (0.01, 0.1 and 1.0 mg/kg) were administered to the dogs (groups 2-6) 5 d/wk for 25 wk. Radiographic and morphometric analyses were performed. In placebo-treated animals (group 2), the
ligation caused a significant decrease in the alveolar bone height by 0.57 and 1.91 mm at 2 and 25 wk, respectively.
YM175 (1.0 mg/kg) prevented the decrease in bone height by 47 and 31% at 2 and 25 wk.
YM175 (0.1 mg/kg) and
flurbiprofen tended to prevent bone loss after 15 wk. Although the
ligation elicited no significant change in bone mineral density, it significantly decreased bone volume.
YM175 (1.0 mg/kg) and
flurbiprofen tended to increase the bone volume. The number of formative or resorptive Haversian canals and the bone turnover through the periosteal bone surface were increased by the
ligation, indicating the increased turnover of the cortical bone.
YM175 (1.0 mg/kg) reduced the increased bone turnover. The gingival index was maximally increased at 2 wk and was suppressed by
YM175. These results suggest that
YM175 prevents
alveolar bone loss by reducing the increased alveolar bone turnover in dogs with
periodontitis.