[A comparative study on clinical effectiveness of activator and Headgear-Activator].

OBJECTIVES: Compare the effects of Activator and Headgear-Activator on growing patients with Class II malocclusion. METHODS: The material consisted of 36 pairs of cephalograms, among which 12 cases were treated with Activator, 17 cases with Headgear-Activator and 9 cases without treatment for control. A reference grid was created to evaluate the skeletal and dental changes quantitatively. RESULTS: Activator and Headgear-Activator were effective on the correction of Class II malocclusion, but the mechanisms were different. CONCLUSION: Both appliances were effective on the correction of skeletal Class II malocclusion of growing patients. By using the headgear, the inhabitation of forward and downward growth of the maxilla was enhanced, and the dental-alveolar changes different from Activator treatment benefit for the improvement of the dental facial appearance of the patient.