Keimyung Medical Journal, Vol.18(2) : 267-274, 1999
Lingual appliances have several clear-cut advantages over labial appliances: 1) "invisible" lingual appliances, 2) reduction of facial surfaces damage 3) no adverse effect on facial gingival tissues, 4) precise evaluation of the position of the teeth, 5) accuracy of evaluation of facial soft tissue contours. But the appliances have disadvantages also; tongue irritation, speech problem, bite opening, difficulty in controlling the torque of anterior teeth, more demand of anchorage value. Author have treated skeletal class H malocclusion with crowding and anterior crossbite. The result could be summarized as follows, Harmonious facial profile and functional occlusion are obtained. Tongue irritation and speech problem were not severe, and adapted easily by patient. There was a increase in mandibular plane angle, but no difficulty in controlling incisor torque.