BACKGROUND: surgery, radiotherapy and chemotherapy are therapeutic modalities used in the treatment of oral cancer. They can be used separately or in combination. Ionizing irradiation causes damage to normal tissues located at the radiation field. This becomes particularly evident in the head and neck region, a complex area composed of several dissimilar structures that respond differently to radiation. The resulting oral sequelae may cause substantial problems during and after radiation therapy and are major factors in determining the patient's quality of life. Xerostomia, osteoradionecrosis, mucositis and candidosis are some of radiotherapy's complications. PURPOSE: introduce health professionals to reflect on issues relevant to oral sequelae of head and neck radiotherapy. CONCLUSION: regular dental follow-up may reduce the effects of radiation in the tissues of the oral cavity.