Long-term (≥ 15years) outcome quality after ClassII:1 bionator or Herbst multibracket appliance treatment : Acomparison.

Abstract

To compare the long-term outcome quality (≥ 15years) of ClassII:1 treatment using either abionator (BIO) or aHerbst-multibracket appliance (HMB). Patients who underwent functional treatment during the ideal treatment period for the respective approach (prepuberty vs. peak/postpeak) were assessed. Inclusion criteria were overjet ≥ 4 mm, skeletal ClassII and availability of study casts from before, after and ≥ 15years after treatment. The study casts were assessed using the Peer Assessment Rating (PAR) index and standard orthodontic cast measurements. During treatment, PAR score, overjet and sagittal occlusal relationship improved significantly in all groups. Long-term, there was asignificant increase of incisor irregularity in the upper (HMB) and lower (BIO) arch and asignificant decrease of lower arch width 3 - 3 (BIO). PAR score, overjet, and sagittal occlusal relationship remained stable long-term. Intergroup comparisons revealed significant differences between the BIO and HMB groups in terms of lower arch width (6 - 6), upper and lower arch width (3 + 3/3 - 3) as well as sagittal molar relationship. The achieved improvement in PAR score, overjet, and sagittal occlusion remained comparably stable long-term in all groups. The long-term changes are probably aconsequence of natural aging.