Abstract
Treatment using the MUH Shield (YC 3 Shield) appliance and that using the chin cap were evaluated. Based on lateral cephalalometric radiographical analysis, changes in craniofacial morphology and tongue position after treatment of deciduous anterior cross bite were compared among the 12 patients in the MUH Shield (YC 3 Shield) group and the 9 patients in the chin cap group, for whom the over jet relationship had inrproved. The following results were obtained.
1. The MUH Shield (YC 3 Shield) group showed labial inclination of the maxillary anterior teeth, flattened occlusal plane, and posteriorly changed, and elevated tongue position.
2. The chin cap group showed a retruded position of the mandibular bone, decreases in mandibular angle, and a posteriorly changed tongue position.
3. It was speculated that functional changes when using the MUH Shield (YC 3 Shield) appliance influenced the skeletal pattern in terms of function during the period of active skeletal growth.
