Dentoskeletal effects and facial profile changes in young adults treated with the Herbst appliance

This prospective Herbst study analyzed the sagittal dental and skeletal cha nges contributing to Class II correction in young adults. Additionally, the alteration in skeletal and soft tissue convexity occurring during treatmen t was assessed. Early adolescent subjects in the permanent dentition who ha d been treated with the Herbst appliance were used for comparison. Lateral headfilms from before and after an average treatment period of 8.5 months f or the young adults and 7.1 months for the adolescents were evaluated. All adult and adolescent subjects were treated to either Class I or overcorrect ed Class I occlusal relationships. In both groups the improvement in sagitt al incisor and molar relationships was achieved more by dental changes than by skeletal ones. The amount of skeletal change contributing to overjet an d molar correction was smaller in the young adult group (22% and 25%, respe ctively) than in the early adolescent group (39% and 41%, respectively). Sk eletal and soft tissue facial profile convexity was reduced in adults and a dolescents. Facial profile improvement did not differ between the two group s. The results of this study revealed that the Herbst appliance is most eff ective in the treatment of Class II malocclusion in young adults. It is sug gested that this treatment method could be an alternative to orthognathic s urgery in borderline Class II cases.