Influence of antineoplastic therapy on function of the masticatory system, tooth development, and cariogenic status: a case report.

Antineoplastic therapy causes developmental disturbances in the dental enamel and root if children are treated during tooth development. Increased caries activity has also been reported. The effect of anticancer therapy on the function of the masticatory system (i.e. jaws, dentition, masticatory muscles) is not well known. A case report of a 9-year-old girl with right auricular rhabdomyosarcoma is presented. She received irradiation of 50 Gy to the right auricular area and chemotherapy. A year and a half after cessation of cancer therapy, she was disease free and the clinical stomatognathic examination combined with electromyogram (EMG) registration of the masseter and temporal muscles and magnetic resonance imaging (MRI) examination of the temporomandibular joints (TMJ) revealed a strongly restricted mouth opening capacity, painful right TMJ, and flattened head of the right mandibular condyle. Muscle atrophy in the right masseter muscle was clearly visible but EMG activities of the masseter and temporal muscles, however, were higher on the right than on the left. More severe developmental defects, and worse gingival and cariological health were observed on the right side than on the left side. She developed 12 carious lesions and all the lesions were on the right maxilla or mandible or on anterior teeth. The left side was not affected. Intensive prophylactic dental care after cancer treatment is important in order to prevent caries and gingival inflammation. Stomatognathic treatment (i.e. management of occlusal and dysfunctional problems) may improve the mouth opening capacity and relieve pain.