Effect of nanoemulsion carbonated hydroxyapatite-statin administration on Acp 5 and Runx-2 expression during orthodontic relapse in rats

Abstract

Background

Retention is an essential element of orthodontic treatment. In the past two decades, numerous biological treatments have been developed to alleviate orthodontic relapse. Pharmacologic bone modulation is a viable approach to mitigate relapse. The aim of this investigation was to determine whether administering nanoemulsion carbonated hydroxyapatite-statin (CHA-statin) would increase Runx-2 expression and decrease Acp 5 expression in rats experiencing experimental orthodontic relapse.

Materials & methods

Forty-eight rats (n = 48) were assigned to four groups: control, CHA, statin, and CHA-statin, with 12 rats in each group. A 30 g mesial traction was applied for 7 days via a closed-coil spring that connected the first maxillary molar to the maxillary incisor. To maintain the moved teeth, CHA, statin hydrogel, and nanoemulsion CHA-statin were administered intrasulcularly every 3 days for a period of 7 days. The removal of the devices facilitated the occurrence of relapse. The expression of Acp 5 and Runx-2 was evaluated using the immunohistochemistry method. The collected data were evaluated using analysis of variance and post hoc tests, with p < 0.05.

Results

A significant reduction in Acp 5-positive cells in the CHA-statin group was observed on days 7 and 14 of relapse movement compared with the other groups (p < 0.05), whereas the average Runx-2 expressions in the CHA-statin groups were significantly higher than in the other groups on days 1, 7, and 14 during the relapse phase (p < 0.05).

Conclusion

The nanoemulsion CHA-statin increased Runx-2 expression and decreased Acp 5 expression, thereby potentially preventing orthodontic relapse in rats.