Enhancement of post-orthodontic tooth stability by carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin in rabbits

Abstract

Objective: To evaluate the effect of carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin on relapse and bone remodelling in rabbits.

Materials and methods: Forty-five rabbits were divided into 3 groups (n = 15): a control group, carbonated hydroxyapatite (CHA) and carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin (CHA-aPRF) group. The lower incisors were subjected to an orthodontic force of 50 cN. During the retention period, CHA and CHA-aPRF hydrogel were gently injected in the mesial gingival sulcus every 7 days. Next, the appliances were debonded to allow relapse. At 5 subsequent time points (0, 3, 7, 14 and 21 days after debonding), the distance between the mesial tips of rabbits incisors was measured using a digital calliper, osteoblast quantity was evaluated using haematoxylin-eosin staining and osteoclast activity was examined using tartrate-resistant acid phosphatase (TRAP) staining.

Results: The relapse rate of CHA-aPRF group was lower than that of the other groups, and the relapse distances were significantly lower on days 14 and 21 (P < .05). Histological analysis revealed that the number of osteoblasts was significantly higher and that the osteoclast activity was significantly lower in the CHA-aPRF group compared with the other groups (P < .05).

Conclusions: Intrasulcular injection of hydrogel CHA incorporated aPRF can locally reduce orthodontic relapse in rabbits.

Keywords: CHA; aPRF; orthodontic tooth movement; osteoblast; osteoclast; relapse.