Clinical and molecular-level comparison between conventional and corticotomy-assisted canine retraction techniques

Abstract

BackgroundOrthodontic tooth movement resulting from coordinated biochemical reactions occurring in and around cells leads to protein synthesis, mitosis, and cell differentiation. This study was aimed at comparing the rate of canine retraction as well as the levels of tumor necrosis factor-α and alkaline phosphatase at specified time intervals during individual canine retraction using corticotomy-assisted and conventional techniques. MethodsTwenty patients (10 boys and 10 girls) with a mean age of 14.5 years and requiring first premolar extractions for orthodontic treatment were included. This split mouth study was carried out where maxillary canine retraction was done by active tie-backs, with corticotomy on the experimental side and without corticotomy on the control side. Rate of retraction was assessed with digital Vernier calipers. Gingival crevicular fluid samples were collected before starting treatment and at 3 days, 7 days, and 1 month from the distal sides of the canine of both sides after the force was applied. ResultsMinimally invasive corticotomy produced an acceleration in the rate of canine retraction by approximately 40%. Tumor necrosis factor-α peaked at the third day in both conventional and corticotomy-assisted canine retraction sides. A gradual increase in the levels of alkaline phosphatase was observed from baseline to 7 days after corticotomy, which remained elevated at day 30. ConclusionsIt was concluded that alveolar corticotomy increased rate of canine retraction by approximately 40%, increased catabolic activities approximately 250%, and increased anabolic activities approximately 42%.