Treatment essentials for Improvement of Jaw-Base Relationship in Class II subjects

Abstract

AIM: The amount any individual can be expected to grow may or may not depend on the particular form of treatment (Johnston, 1999). The aim of this study was to investigate the apical-base change with various treatments of a Class II malocclusion SUBJECTS AND METHOD: Three patient groups were compared: (1) the ‘gold standard’ group: Edgewise therapy (Johnston, 1999), (2) Class II elastic group: 18 consecutive subjects, non-extraction with Begg, and (3) Headgear-functional appliance group: 18 consecutive subjects, headgear-Herbst and step-wise advancement of the mandible followed by a headgear-activator. Lateral cephalograms were obtained for all groups at the start of treatment (T0), and after 6 (T6), 12 (T12) and 18 (T18) months (groups 2 and 3), and after 24 months (group 1). RESULTS: The antero-posterior (A-P) distance had improved 2.3 mm*** in group 1 after 24 months. In group 2 it worsened 0.5 mm at T6, improved 0.4 mm at T12 and 1.1 mm** at T18. In group 3 it had improved 3.1 mm*** at T6, 5.6 mm*** at T12 and 6.3 mm*** at T18. At T24 the groups had 74, 41 and 36 per cent of A-P change versus the groups at T6, T12 and T18. Group 1 had 20 per cent of the A-P change of group 3 at T18. CONCLUSION: The choice of orthodontic device used for improvement of the apical base relationship in the treatment of Class II malocclusions seemingly matters to a clinically significant level. However for some orthodontic devices the treatment change of A-P distance might not differ significantly from that of growth only.