A study on treatment effects of different activator types in Angle's Class II div.1 malocclusion patients

Kim, Duk Snag; Lee, Jin Woo; Cha, Kyung Suk

Abstract

This research was carried out to compares the treatment effects of Horizontal and Vertical type activators in Angle's Class II div. 1 maloccusion patients with mandibular retrusion dand to find out whether different treatment effects or growth pattern were observed between sexes in each study groups. The results were as follows: 1. In Horizontal activator group, forward positioning of mandible and vertical increase in anteror face as examplified by increase of LAFH and AFH were observed when pre and post-treatment datas were evaluated. 2. Males samples in Horizontal activator group showed increase in mandiular length accmpanied by posterior positioning of maxilla, wheras female samples in Horizontal activator group showed increase in mandibular body length,labial inclination of mandibular incisors and increase in lower anterior facial height . 3. In vertical activator group, increase in AFH, LAFH, PFH and LPFH were observed when pre and post treatment datas were a aluated. 4. Male samples in Vertical activator group showed increase in mandibular body length and anterior and posterior facial heights, whereas females samples of Vertical activator group showed mainly increase in anterior facial height 5. When pre and post treatment datas of Horizontal and Vertical activator groups were compared, skeletal difference were mainly observed in eatrnnt datas but dental difference were observed in post treatment datas ,indicating that two actiators differ only in their effects to dental variables. 6. Difference between sexes were noted after treatment although no difference were observed between sexs in each groups before treatment This indicates that inherent growth effects in each sex exerts more influence than appliances used for treatment.