Clinical effect of bone-anchored pendulum in treatment for class II malocclusion

Abstract

Objective To study the clinical effect of bone-anchored pendulum in treatment for class Ⅱ malocclusion. Methods Twelve patients treated by bone-anchored pendulum were chosen. In each patient, two microscrews were inserted in the anterior paramedian region of the median palatal suture, 6-9 mm posterior to the incisive foramen and 3–6 mm lateral to the median line. Pendulum that based on the microscrews was used to distalize maxillary first molar, and the force applied was 250 g. Skeletal and dental changes were measured on cephalograms before (T1) and after (T2) distalization. Results Class Ⅰ molar relationship had been obtained 7 month after distalization. The average distal movement of the maxillary first molars was 7.07 mm, and the inclination was 9.93°. The second premolars were distalized an average of 5.44 mm with inclinations of 5.22°. The first premolars were distalized an average of 4.09 mm with inclinations of 3.95°. The maxillary anterior teeth were retruded 0.93 mm and palatally inclined 1.66°. There was statistical difference in that change. Conclusions By the use of microscrew, pendulum can distalize maxillary molar effectively without mesial movement of premolar and labial movement of incisor, and no loss of dental anchorage is observed during the distal movement. Key words: Malocclusion, Angle Class Ⅱ; Orthotic Devices; Dental implantation; Bone-anchored pendulum