Effect of Local Zoledronic Acid Application in Alveolar Bone Healing: An Experimental Study.

Background: This experimental study aimed to assess the three-dimensional and histological changes of the alveolar socket with local application of ZA.

Methods: Nine male New Zealand white rabbits were randomly allocated into 4-, 8-, and 12-week groups after the extraction of 4 incisor teeth. The upper and lower right sockets were filled with ZA + collagen sponge (ZA-CS group), while the left sockets were filled with collagen sponge alone (CS group) postoperatively. At 4, 8, and 12 weeks (T1, T2, and T3) after the extraction, radiographic and histomorphometric evaluations were conducted for both groups.

Results: The increase in alveolar bone density of the ZA-CS group at T2 and T3 was significantly higher than the CS group (P＜0.01). Three-dimensional evaluations demonstrated no statistically significant differences in ridge height and width between the 2 groups at T2 and T3. On histological evaluation, the ZA-CS group included significantly fewer TRAP-positive cells than the CS group at T1 (P＜0.05). In ALP staining, all cases in both groups were classified as positive at each time point. Masson trichrome staining showed significantly higher mean red collagen volume fraction in the ZA-CS group (76.09%, 79.64%) than in the CS group (66.17%, 69.22%) at T2 and T3, respectively (P＜0.05 and ＜0.01).

Conclusions: Although local ZA application with collagen sponge did not reduce alveolar ridge contraction, it improved the bone density and maturity of newly formed bone after tooth extraction.