Locally inhibition of orthodontic relapse by injection of carbonate apatite-advanced platelet rich fibrin in a rabbit model
Ananto Ali Alhasyimi1, 2, Pinandi Sri Pudyani2, Widya Asmara3, Ika Dewi Ana4
1Graduate School of Dental Sciences, Universitas Gadjah Mada, Indonesia (email: email@example.com )
2Department of Orthodontics, Faculty of Dentistry, Universitas Gadjah Mada, Indonesia
3Department of Microbiology, Faculty of Veterinary Medicine, Universitas Gadjah Mada, Indonesia
4Department of Dental Biomedical Sciences, Faculty of Dentistry, Universitas Gadjah Mada, Indonesia
Introduction. Relapse is considered a significant failure in orthodontic treatment. Stimulation of alveolar bone formation and inhibition of bone resorption is believed could effectively prevent the relapse . In response to relapse, receptor activator of nuclear factor-κB ligand (RANKL) expressions will increase, while osteoprotegerin (OPG) expressions will decrease . Carbonated hydroxyapatite (CHA) is thought to be one of an ideal candidate for enhancing bone formation since it is potential to raise the local concentration of calcium and phosphate ions . Advanced platelet-rich fibrin (a-PRF) is a new generation of PRF which contains high levels of growth factors that play a central role in the bone remodelling . This research was intended to investigate the effect of hydrogel CHA incorporated a-PRF intrasulcular injection in preventing orthodontics relapse.
Experimental. Forty-five New Zealand male rabbits lower incisors were moved distally with an orthodontic force of 50 cN. The subjects were grouped into Group A (control), Group B (CHA), and Group C (CHA-aPRF) with 15 Rabbits in each group. After 1 weeks, the distance was maintained during 2 weeks of retention period, the intrasulcular injection of CHA and CHA-aPRF (0.5 ml) was then given every 7 days. The brackets were then debonded, gingival crevicular fluid was taken on day 0, 3, 7, 14 and 21, and the RANKL and OPG expressions were measured by Enzyme Linked Immunosorbent Assay (ELISA) kits. The relapse distance was recorded using a digital calliper. Data were analyzed by a two-way ANOVA and Tukey’s test with a significance level of 95%.
Results and Discussion. It has been found that expressions of RANKL were significantly lowest (p<0.05) in groups C on day 0, 3, and 7, while OPG expressions showed significantly highest (p<0.05) in groups C on day 14 and 21 after debonding (Fig.1). RANKL promotes osteoclastic differentiation and activation, while OPG inhibits RANKL, hence blocking osteoclastogenesis leading to decreased bone resorption . They also showed a trend toward an increase in relapse distance, while group C showed lowest percentage of relapse distance (29.95±3.91%) compared to other group.
Conclusions. Intrasulcular injection of CHA incorporated a-PRF potential to reduce orthodontic relapse by stimulating OPG expression and suppressing RANKL expression.
 Hassan AH, Al-Hubail A, Al-Fraidi AA. Angle Orthod 2010;80:1051-60.
 Yamaguchi M. Orthod Craniofac Res 2009;12(2):113-9.
 Ana ID, Matsuya S, Ishikawa K. Engineering 2010;2: 344-52.
 Kobayashi E, Flückiger L, Fujioka M, Sawada K, Sculean A, Schaller B. Clin Oral Invest 2016;25: 1-8.
 Alhashimi N, Frithiof L, Brudvik P, Bakhiet M. Am J Orthod Dentofacial Orthop 2001;119:307–12.