Abstract:

Objective This study is to evaluate the soft tissue change of Angle′s Class Ⅱ division 1 malocclusion patients with vertical growth pattern after tooth extraction orthodontic treatment, and to provide experimental results to help to make orthodontic treatment plan and treatments. Methods 38 Angle′s Class Ⅱ division 1 malocclusion patients with vertical growth pattern and with tooth extraction orthodontic treatment were included in this study. The pre- and post-treatment cephalometric X-rays were made and 26 measurement items were measured. The change value of pre- and post-treatment, youngsters and adults were compared. Results TUL-EP, TLL-EP, upper and lower lip position, Stoms-Stomi, U1-Ptm were reduced after treatment. Upper lip sulcus and flange thickness, upper and lower lip length, upper and lower lip inclination angle, nasolabial angle, Z angle, mentolabial sulcus inclination angle were enlarged after treatment. The upper lip sulcus thickness, lower lip length and A′-Ptm of adolescent were enlarged, but adult were on the contrary. The change of upper lip length, mentolabial sulcus inclination angle and U1- Ptm between adolescent and adult was statistically different. Conclusion The best treatment period of patients with Angle′s Class Ⅱ division 1 malocculsion with vertical growth pattern was in the rapid growth and development period of adolescent.

Key words: vertical growth pattern, Angle′s Class Ⅱ division 1 malocclusion, orthodontic treatment, tooth extraction, soft tissue change