According to the classification of the World Health Organization (WHO), the most common childhood malignant neoplasms include leukemia, lymphomas, and neoplasms of the central nervous system (CNS) and the sympathetic nervous system. Cancer diseases themselves as well as their treatment carry a high risk of both early and distant effects. The most common dentition disorders resulting from the radiotherapy of the head area and chemotherapy in patients up to the age of 6 years include root agenesis, V-shaped roots, microdontia, hypoplasia of the maxilla and the jawbone, hypodontia, and enamel hypoplasia and hypomineralization. Patients undergoing oncological treatment at the age of <6 years should receive adequate and long-term monitoring due to the possible distant effects of the underlying disease and its treatment. The radiotherapy of the head and neck region performed on a growing patient significantly worsens the patient's prognosis and results in a number of irreversible complications. Planning appropriate orthodontic treatment in such patients contributes to increased comfort later in the patients' lives. Oncology patients do not require special orthodontic procedures; however, the high risk of complications does encourage the planning of orthodontic treatment with the least burden. Dental care for a young patient with a history of oncological disease requires the interdisciplinary cooperation of a pedodontist, orthodontist, prosthetist, and dental surgeon.
Keywords: chemotherapy; dental abnormalities; pediatric oncology; radiotherapy.