A Study of the Changes of Dentofacial Soft and Hard Tissue of Skeletal Class II~1 Malocclusion Induced by Headgear Activator

Objective:This study analyzed the changes of dentofacial soft and hard tissue of skeletal Class Ⅱ 1 malocclusion induced by Activator with Headgear.Methods:10 mixed or early permanent dentition class Ⅱ 1 cases were selected:4 males and 6 females.The design of appliance was referred to Graber and Van Beek's.Average treatment time was 10.2 months.33 measurements were selected for cephalometric analysis before and after treatment,and statistical analysis was performed by SAS statistic software.Results:SNA,ANB,and overjet were decreased by 1.17°,2.3°,and 6.07°,respectively.While SNB increased by 1.16°.Upper incisors were inclined backward and lower incisors were inclined forward.The total facial height,anterior facial height,and posterior facial height were all increased.It indicated that there were significant changes of dentofacial of soft and hard tissue.