[Soft tissue changes following the treatment of Class II division 1 malocclusion using Headgear-activator appliance].

Purpose: To investigate the soft tissue changes following the treatment of Class II division 1 malocclusion using Headgear-activator appliance.

Methods: Fifty Class II division 1 malocclusion subjects who were at peak high velocity on the growth curve were divided into two groups. Standardized lateral cephalogram was taken for each patient in the two groups before and after treatment. SPSS11.0 software package was used to calculate the mean and standard deviation, matched t-test was used to evaluate the changes of the soft tissues.

Results: The angle of CmSnLs,LiB'Pg' and Z increased, the angle of H, LsNsLi and LsNsPg' decreased, there was statistically significant difference between the two groups.

Conclusions: Using Headgear-activator appliances, soft tissue profile is effectively improved. Soft tissue chin is moved forward obviously. Lip protrusion is decreased.