Comparison of the efficacy of two-time versus one-time micro-osteoperforation on maxillary canine retraction in orthodontic patients: A split-mouth randomized controlled clinical trial.

Background: Micro-osteoperforation (MOP), a minimally invasive technique for accelerating the rate of orthodontic tooth movement has been research extensively, but with varied clinical results.

Objective: To compare the efficacy of one-time versus two-time micro-osteoperforation on the rate of maxillary canine retraction, its influence on anchorage loss, canine angulation and the levels of interleukin (IL-1β) in gingival crevicular fluid (GCF).

Materials And Methods: The split-mouth study included 16 patients in which the left and right sides were randomly allocated to the control side (one-time MOP) and experimental side (two-time MOP). MOP was performed on both sides distal to the maxillary canines and canine retraction was carried out using NiTi closed coil springs (150gm) and direct anchorage with miniscrew implants. The second MOP was performed on experimental side one month after the first MOP. The rate of canine movement was assessed using 3D model superimposition over a period of six months. The type of tooth movement, anchorage loss and levels of IL-1β were also evaluated.

Results: Sixteen patients (mean age, 17.87±3.34 years) were analysed for a rate of canine retraction, anchorage loss, and type of tooth movement, while 15 patients were analysed for IL-1β. The rate was significantly higher on two-time MOP side after two months (P<0.001). No statistical difference was found in anchorage loss and controlled tipping of canines was observed. The IL-1β levels immediately after 2 MOP were significantly higher than 1 MOP (P<0.001).

Conclusion: The two-time intervention of MOP is more efficacious than one-time MOP in accelerating tooth movement.