The stability of Class II correction with functional appliance therapy and orthodontic camouflage: A retrospective...

The aim of this study was to compare the stability of overjet reduction in adolescents treated with either orthodontic camouflage involving extraction of premolar units or functional appliance therapy.

A retrospective cohort study was undertaken with data collected at pre-treatment (T0), debond (T1) and 12 months post-treatment (T2). The primary outcome measure was stability of overjet reduction, and secondary outcome measures included Angle's molar relationship, and Little's Irregularity Index score.

Forty-two Class II participants, 18 treated with a functional appliance and 24 with camouflage, were included with a mean pre-treatment age of 13.07 years (SD 1.72), with 23 (55%) being female. Mean overjet reduction during treatment in the functional appliance group was 6.99mm with relapse of just 0.62mm present at 12 months post-treatment. In the orthodontic camouflage group, there was a mean overjet reduction of 3.54mm with relapse of 0.27mm at 12 months post-treatment. Linear regression analysis confirmed no statistical difference (P=0.501) in overjet relapse between both treatment groups at 12 months post-treatment, adjusting for overjet at baseline. A further regression analysis revealed no significant association between overjet relapse and pre-treatment skeletal discrepancy, labial segment crowding, retention regime or compliance with the retention protocol.

Both functional appliance and orthodontic camouflage therapies appear to have good antero-posterior occlusal stability, with minor degrees of overjet relapse occurring over a 12-month follow-up period. There was no significant difference between the treatments in relation to overjet relapse, buccal segment interdigitation or anterior irregularity.