Bone wound healing after maxillary molar extraction in ovariectomized aged rats: Quantitative backscattered electron image analysis

Abstract

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.

Acute effects of ovariectomy on wound healing of alveolar bone after maxillary molar extraction in aged rats

“…In our previous BSE observations, newly-formed bone at this site was significantly decreased by ovariectomy (Shimizu et al, 2000). The mean area of newly-formed bone mass on the buccal side of extracted alveolar sockets at 60 days after molar extraction, however, was only 85.4 m 2 /1,000 m at 7 days post-ovariectomy [present data], whereas that at 60 days post-ovariectomy was 358.3 m 2 / 1,000 m (Shimizu et al, 2000).…”

“…In OVX rats, the newly-formed bone area (m 2 /1,000 m) was significantly (*P Ͻ 0.01) reduced as compared with that in sham-operated controls at 60 days after molar extraction. the buccal alveolar bone surfaces after molar extraction continues until the late phase post-ovariectomy (Shimizu et al, 1998(Shimizu et al, , 2000, post-menopausal estrogen deficiency is suggested to be a strong risk factor for poor bone wound healing and bone strength after tooth extraction. …”

“…Recently, Shimizu et al (1998Shimizu et al ( , 2000 reported that, at 60 days post-ovariectomy, bone wound healing after maxillary molar extraction was significantly reduced by increased bone resorption. The acute effects of estrogen depletion by ovariectomy on the bone wound healing processes, however, remain to be clarified.…”

Bone Regeneration of Hydroxyapatite with Granular Form or Porous Scaffold in Canine Alveolar Sockets

“…From these points, the bone-specific surface may be affected depending on structural changes. Therefore, if the bone parameters by micro-CT are associated with bone loss in osteoporosis, values of BMD, bone volume/tissue volume, trabecular thickness, and trabecular number will decrease, and trabecular separation and bone surface/bone volume will increase (21,22). In this study, trabecular thickness and low trabecular number were higher in the gHA group than in the pHA group.…”

Evaluation of osteoporosis in jaw bones using cone beam CT and dual-energy X-ray absorptiometry

“…Previous reports have indicated that as with other osteoporotic bones, there are negative effects on implant treatment in the socket of an extracted tooth, including a decrease in the rate of bone formation, alveolar bone interdental bone thickness, and in the density and thickness of the mandibular inferior cortex (18)(19)(20).…”