Facial profile changes in early class II correction with cervical headgear

Objective: To characterize the effects of early cervical headgear treatment on the facial profile of children in Class II division 1 malocclusion. Materials and Methods: Forty children aged 9.1 (7.2-11.5) years with Class II division 1 malocclusion were treated using a cervical headgear appliance. The headgear consisted of a long outer bow bent upward 15 degrees and a large expanded inner bow. Lateral cephalograms were taken before and after treatment, and the facial profile was estimated from the cephalograms. The results were compared to an age- and sex-matched normal cohort of 644 Finnish children. Results: Class I molar relationship was achieved in all treated children. The treatment time was 1.6 (0.3-3.1) years on average. Compared to the controls, the treatment restricted the forward growth of maxillary A-point, and the SNA angle decreased 1.4 degrees +/- 1.2 degrees per year (P < .00001). Decreased maxillary prognathism was associated with decreased facial convexity, g-sn-pg (P = .02), and the ANB (P < .00001) angles decreased compared to the controls. Upper lip protrusion (distance ls to sn-pg; P < .00001) was decreased, and the nasolabial angle (cm-sn-ls) widened despite the increased facial inclination of the upper incisors (P = .0005). The treatment significantly decreased the gap between the lips (P = .0009) in their relaxed position. Conclusion: Cervical headgear treatment in Class II correction is associated with a decreased facial convexity caused by the restriction of forward growth of the maxillary A-point, while the rest of the facial profile, including the mandible, continue to grow forward at a normal rate.