RESUMEN
Nasopharyngeal carcinoma (NPC) is a rare and distinct malignancy that arises from the epithelium of the nasopharynx. It accounts almost 1% of all pediatric malignancies. Oral complications of radiotherapy in the head and neck region are the result of the deleterious effects of radiation on salivary glands, oral mucosa, bone, dentition, masticatory musculature, and temporomandibular joints. Here we present 3 male NPC patients 13, 14 and 15 years old. One of them had stage III and the others stage IV diseases. Administered dose of radiation was 66 Gy for case I, 70 Gy for case II and 68 Gy for case III. The follow-up period was more than 12 months except for case III and all of them were disease free in their last visit. All attended dental clinics for dental and TMJ problems. Dentitions were severely affected, trismus and severe xerostomia. Long-term effects of radiotherapy which has a great impact on patients' quality of life and the role of supportive care and minimizing the late effects of ionizing radiation are discussed.