Long-term skeletal effects of high-pull headgear followed by fixed appliances for the treatment of Class II malocclusions

Abstract

Objectives: The long-term skeletal effects of Class II treatment in growing individuals using high-pull facebow headgear and fixed edgewise appliances have not been reported. The purpose of this study was to evaluate the long-term skeletal effects of treatment using high-pull headgear followed by fixed orthodontic appliances compared to an untreated control group. Materials and Methods: Changes in anteroposterior and vertical cephalometric measurements of 42 Class II subjects (n ¼ 21, mean age ¼ 10.7 years) before treatment, after headgear correction to Class I molar relationship, after treatment with fixed appliances, and after long-term retention (mean 4.1 years), were compared to similar changes in a matched control group (n ¼ 21, mean age ¼ 10.9 years) by multivariable linear regression models. Results: Compared to control, the study group displayed significant long-term horizontal restriction of A-point (SNA ¼1.9258, P, .0001; FH-NA ¼3.0428, P, .0001; linear measurement A-point to Vertical Reference ¼3.859 mm, P, .0001) and reduction of the ANB angle (1.7678, P, .0001), with no effect on mandibular horizontal growth or maxillary and mandibular vertical skeletal changes. A-point horizontal restriction and forward mandibular horizontal growth accompanied the study group correction to Class I molar, and these changes were stable long term. Conclusions: One phase treatment for Class II malocclusion with high-pull headgear followed by fixed orthodontic appliances resulted in correction to Class I molar through restriction of horizontal maxillary growth with continued horizontal mandibular growth and vertical skeletal changes unaffected. The anteroposterior molar correction and skeletal effects of this treatment were stable long term.