Method: Forty female Wistar rats (Rattus norvegicus, albinus) with normal oestrus cycles were randomly divided into two groups (N=20 per group); 1) ovariectomized (OVX) followed by immediate extraction of the maxillary central incisors and replantation with 30- or 60-day follow up; 2) sham surgery without OVX followed by immediate extraction of the maxillary central incisors and with tooth replantation with 30- or 60-day follow up. Atraumatic tooth extraction was performed with the extracted tooth immediately replanted. Following euthanasia, bloc specimens of the maxillary incisors and maxilla were removed, processed, embedded in paraffin. Longitudinal 6-µm-thick sections were cut and further analyzed.
Result: The gingival epithelial attachment occurred at the cementoenamel junction in sham control groups except in one specimen at 60 postoperative days. Sham group has shown that none of the specimens exhibited areas of root resorption at 60 postoperative days however, at 30 postoperative days one specimens exhibited areas of root resorption in the middle 1/3 of the root. The periodontal ligament (PDL) space was filled by fibrous connective tissue and bone tissue in the sham control group at 60 days. The OVX group showed diminished PDL space that was replaced by either disorganized connective tissue, and less frequently, with islands of bone tissue. Areas of cementum and dentin resorption occurred in the middle third of the root in some specimens.
Conclusion: Repair processes for immediate tooth replantation are compromised following surgically induced ovariectomy. Multiple areas of osteoclastogenesis in association with OVX and tooth replantation indicate that interventional strategies should be developed for post-menopausal tooth replantation patients.