Purpose: To evaluate the difference of treatment on growing patients with Class II division 1 using various anteroposterior and vertical skeletal dysplasias.
Methods: Twenty-eight moderate to severe Class II division 1 malocclusion patients with Class I molar and canineocclusion after treatment were selected. The subjects were divided into 3 groups based on the initial ANB and FMA angles. Pre-treatment and post-treatment cephalograms were evaluated for soft and hard tissues changes after treatment. The data was analyzed using SPSS 12.0 software package.
Results: ANB angle decreased in all three groups. Changes of ANB angle in group 2 and group 3 were greater than group 1(P<0.01). SNA angle decreased significantly in group 3(P<0.01). SNB angle increased significantly in group 1(P<0.01) and group 2(P<0.05). All groups had great maxillary incisors retraction and similar changes in mandibular incisor positions.Soft tissue index showed no significant difference among three groups before and after treatment(P>0.05). But nasolabial angle(P<0.05), soft tissue convexity(P<0.05) and Z angle(P<0.01) changed significantly in group 3.
Conclusions: Conventional orthodontic therapy successfully corrects Class II division 1 malocclusions in growing patients with the improvement of soft and hard tissues.The patients who initially have the most severe skeletal dysplasias can have the greatest changes in profile.