Comparison of efficacy between modified forsus appliance and activator appliance in the treatment of class II patients with madibular retrusion

Abstract

Objective To evaluate and analyze the effects between with modified Forsus appliance and activator in the treatment of class Ⅱ madibular retrusion.Methods 70 children with class Ⅱ malocclusion and mandibular retrusion were selected and divided into two groups:35 patients treated with this modified Forsus appliance (group A) and other 35 treated with activator (group B).Cephalometric radiographs were taken and analyzed at the pre-treatment time (T0) and the post-treatment time (T1) with the Pancherz analysis.Results The course of treatment was obviously different:the course of group A was (21.4±2.0) months,and group B was (27.3±2.5) months; the treatment course of group A was shorter than that of group B.After treatment,profiles of the two groups were obviously improved.The trends were similar in overjet and the molar relationship,SNB and ANB,with significant differences.But there was no significant difference between the results of the two groups.The change of occlusal plane was notably in group B.Conclusions Both the modified Forsus appliance and activator appliance combined with straight wire appliance can effectively stimulate the mandibular growth,balance the jaw relationship,and correct the class Ⅱ mandibular retrusion.But the modified Forsus appliance can effectively treat the class Ⅱ patients with the shorter course.And the same time,it can take effect continually without depending on the coordination of the patients. Key words: Forsus appliance; Activator; Pancherz analysis; Mandibular retrusion