Bone wound healing after maxillary molar extraction in ovariectomized aged rats: quantitative backscattered electron...

The processes of bone wound healing after maxillary molar extraction in ovariectomized aged rats were examined by means of quantitative backscattered electron image analysis and energy-dispersive X-ray microanalysis. Six-month-old female rats were either sham-operated or underwent bilateral ovariectomy (OVX), and 60 days postoperatively, the maxillary first molars were extracted. On post-extraction days 7, 30, and 60, the dissected and resin-embedded maxillae were micromilled in the transverse direction through the extracted alveolar sockets, and new bone formation on the buccal maxillary bone surface and within the extracted alveolar sockets was examined. In both sham-operated control and OVX rats, new bone formation was recognized on the buccal bone surface, as well as within the extracted sockets, and increased daily through to day 60. In comparison to sham-operated controls, new bone formation in OVX rats was significantly decreased both on the buccal bone surface and within the extracted sockets. Our results suggest that bone wound healing by new bone formation after maxillary molar extraction is significantly decreased in OVX-induced osteoporosis.