Effect of injectable platelet-rich fibrin (i-PRF) in accelerating orthodontic tooth movement A randomized split-mouth-controlled trial

Background The role of platelet-rich fibrin (PRF) in accelerating orthodontic tooth movement has been controversially discussed in available clinical studies. Objective To investigate the effectiveness of i-PRF in accelerating maxillary canine retraction. Materials and methods A split-mouth design was applied in 21 participants (6 men, 15 women; mean age: 20.85 +/- 3.85 years) whose class II division I malocclusion required the extraction of both maxillary first premolars. The right and left canines were randomized into intervention and control sides. After the initial leveling and alignment phase and immediately before canine retraction, i-PRF obtained from the brachial vein was injected into the mucosa on the buccal and palatal aspects of the intervention sides. The injection was repeated one month later. Study casts were taken at the initiation of canine retraction (T0) and at monthly visits up to 5 months (T1 through T5). The paired t-test was used to compare the total and monthly rates of canine retraction, canine rotation, and anchorage loss. Results The average rates of canine retraction were greater on the experimental side at T2, T3, and T4, but this difference with the control side was statistically significantly different only at T2 (P < 0.05). Differences in canine rotation and anchorage loss were not statistically significant. Conclusion The rates of canine retraction following the injection of platelet-rich fibrin were not statistically significantly greater on the experimental than the control sides except at the second month (T2). This apparently transient rate of tooth movement indicates that repeated injections might be needed for sustained effects, a premise meriting more focused research.