Long-term soft-tissue response to orthodontic treatment with early cervical headgear--a randomized study.

INTRODUCTION The purpose of this longitudinal randomized investigation was to determine the long-term changes in the soft-tissue profile during orthodontic treatment when treatment is started with headgear (HG) in the early mixed dentition. METHODS The subjects were 68 children (28 girls, 40 boys; mean age, 7.6 years; SD, 0.3 years) with a Class II tendency in occlusion and moderate crowding. They were randomly divided into 2 groups. In the HG group, treatment began immediately. No other appliances were used during the first 2 years. In the control group, only minor interceptive procedures were performed during the first follow-up period of 2 years. During the 8-year follow-up, orthodontic treatment, if needed, comprised fixed appliances and possible extractions in both groups. Twenty linear and 5 angular soft-tissue measurements were registered from lateral cephalograms taken before treatment and after follow-up-periods of 2, 4, and 8 years. RESULTS The major findings were that, at the 8-year follow-up, the soft-tissue chin and the lower lip were significantly thicker, and the mentolabial sulcus was significantly deeper in the HG group than in the control group. In the control group, a larger variation in the upper lip position was found because of more extractions in this group. CONCLUSIONS Early HG treatment has only a minor effect on the soft-tissue profile. The main effects are on the thickness of the soft-tissue chin and the contour of the lower lip. The differences were not otherwise significant during the long-term follow-up.