Abnormal forces cause malocclusion . There are a number of patients whose malocclusions entail more than just the malposition of teeth alone . Often there are orthopedic discrepancies and muscular dysfunctions as well. The goal of functional orthopedics is to control and direct these forces to prevent or correct malocclusion . Functional appliances are considered to be orthopedic in nature , influencing the facial skeleton of the growing child in the condylar and suture areas . Functional appliances also exert an orthodontic effect on the dentoalveolar structures.