Which Way Forward? Fixed or Removable Lower Retainers

Abstract

Abstract Objective: To determine whether lower lingual, canine to canine, bonded multistrand retainers prevent relapse of lower labial segment alignment following fixed appliance therapy and to compare this with lower Hawley-type removable retainers. Materials and Methods: Two groups of 29 patients were identified. Group 1 had bonded lower canine to canine multistrand retainers placed following debonding, whereas Group 2 had lower Hawley-type retainers (with acrylic labial to the incisors) fitted following debonding. Study models were taken of all patients at debonding (T1) and at least 1 year post debonding (T2). Changes in Little's index over the study period were recorded using a reflex microscope. Results: Statistically significant changes in Little's index occurred in the lower labial segment of both study groups (P = .001) over the observation period. There was no statistically significant difference in the amount of change in Little's index between the bonded and removable retainer groups (P = .13). Bonded retainers tended to be placed in older patients (P = .02). Conclusions: Relapse can occur in the lower labial segment with both fixed and removable retainers. The amount of relapse seen with both types of retainer is not statistically significantly different.