Treatment of Class II, div. 1 malocclusion with the activator and with the Begg technique.

The effect of treatment of Angle Class II, division 1 malocclusion with an Andresen activator or with the Begg technique with or without premolar extraction was studied retrospectively with X-ray cephalometry. The treatment with the Begg technique was followed by a phase of retention with an activator. Three groups of 25 children who had been treated with one of the methods were compared regarding facial morphology and soft tissue profile before and after the treatment and changes during the period of treatment. The treatment effect (correction of the distal occlusion and normalisation of the overjet and overbite) was similar with the three methods. The overjet was mainly corrected through skeletal changes, which accounted for 70%, 77% and 62% of the overjet correction produced by the activator, Begg extraction and Begg non-extraction treatment, respectively. Thus, all three methods of treatment had a skeletal (orthopedic) effect. The dental component of the overjet correction was with all three methods of treatment a retroclination of the upper incisors. This was to some extent offset by a retrusion of the lower incisors, which also occurred in all groups. The facial morphology and the soft tissue profile after the treatment were similar in the three groups. There were no differences in the soft tissue profile and only marginal differences in facial morphology as a result of the three methods of treatment.