Temporomandibular joint ankylosis (TMJA) may be fibrous or bony (resulting from the fusion of articular surfaces, glenoid fossa, and mandibular condyle). A multidisciplinary approach is necessary to successfully rehabilitate patients with this condition since it can cause problems related to psychosocial, nutritional, facial, and occlusal factors. Depending on the patient’s age, orthotic intervention may be necessary in order to correct the malocclusion caused by TMJA. This article presents the case of a pediatric patient with idiopathic left TMJA who underwent multidisciplinary treatment at a reference center for craniofacial anomalies in western Parana. Balters Bionator orthopedic appliances were initially used, followed by rapid maxillary expansion using a Hyrax expander. This resulted in improved masticatory, esthetic, and speech functions, particularly mouth opening, as well as partial correction of mandibular asymmetry and the occlusal plane within the limits of the case. The use of functional and mechanical orthopedic appliances contributed to improved facial function and esthetics, and the multidisciplinary team’s care was essential to improving the patient’s quality of life during the rehabilitation process.