Evaluation of the effectiveness of the platelet-rich plasma compared to the injectable platelet-rich fibrin on the rate of maxillary canine retraction: a three-arm randomized controlled trial.

Background: Blood-derived materials have been used recently to accelerate orthodontic tooth movement, but there are conflicting reports on their effectiveness.

Objective: To evaluate the potential effect of local injection of platelet-rich plasma (PRP) and injectable platelet-rich fibrin (i-PRF) on the rate of orthodontic tooth movement.

Trial design: A single-center, three-arm, parallel-group randomized controlled trial.

Materials and methods: The sample consisted of 60 patients aged between 18 and 25 years (mean age: 21.1 ± 2.2 years) with Class II division 1 malocclusion requiring anterior retraction. Using a computer-generated list of random numbers, patients were assigned to three groups of canine retraction: (i) assisted with PRP injection (PRP group), (ii) assisted with i-PRF group, and (iii) conventional treatment with no injections (Cont. group). In the interventional groups, injections were done immediately and at 8 weeks after the onset of canine. Transpalatal arches (TPAs) were used to reinforce anchorage. The upper canines were distalized on 0.019 × 0.025-inch stainless archwires using coil springs with a force of 150 g. The primary outcome was the amount of canine retraction, whereas the secondary outcomes were canine rotation and anchoring loss. Assessment was done at five-time points: the beginning of tooth movement (T0) and at 4, 8, 12, and 16 weeks following T0 on three-dimensional superimposed digital models.

Results: Sixty patients were randomized and included in this study (20 patients in each group), there were no dropouts. The rate of canine retraction was faster in the experimental groups. The PRP group showed a significantly slower movement in the second and fourth months than the i-PRF group while in the first and third months, there were nonsignificant differences between the two experimental groups.

Limitations: Blinding was not possible during the clinical stage of this trial.

Conclusions: PRP and i-PRF were found to be effective in accelerating orthodontic tooth movement during canine retraction. However, the effect of i-PRF was longer than that of PRP.

Trial registration: ClinicalTrials.gov (ID: NCT05335824).