To appraise the effect of bisphosphonate therapy on tissue healing following oral surgeries, an animal experiment was conducted including tooth extraction, bone grafting, and implant placement. The current paper reports clinical and histologic observations of extraction socket healing.
Methods:
Twelve healthy adult female mongrel dogs were assigned to two experimental and one control groups (n=4 each). The experimental groups received oral alendronate (ALN, 3.5mg/kg/week) or IV pamidronate (PAM, 4.5mg/kg/week), for twelve months. Subsequently, concentrations of serum C-terminal cross-linking telopeptide of type I collagen (CTx) were measured. The bilateral first and second premolars were extracted in each animal. After 8 weeks, in case of bone necrosis in extraction areas, sequestra were collected for histologic appraisal.
Results:
CTx levels were lower in the experimental groups. After 8 weeks, wound healing was suppressed in both experimental groups (more severe in the PAM group). Bone necrosis involved the entire alveolar bone in the PAM group and the upper rim of the alveoli in the ALN group. Histological appraisal demonstrated empty osteocyte lacunae in samples from PAM-treated animals. In specimens from ALN group, areas of necrotic bone were distinguished along with evidence of active bone remodeling.
Conclusions:
One- year treatment with high doses of ALN/ PAM was associated with alveolar bone necrosis in dogs. The impairing effects of IV PAM on extraction socket healing were more severe in comparison to oral ALN. Within the limitations of this study, CTx test demonstrated the decreased bone turnover related to BP therapy; the readings however did not signify the severity of bone turnover reduction.