Oral health and disturbances in dental development were studied in long-term survivors after antineoplastic therapy. Fifty-seven children treated with combination chemotherapy and 19 children treated with total body irradiation (TBI) prior to bone marrow transplantation (BMT) were examined. The variables studied were dental caries, salivary flow, salivary microbial counts, enamel disturbances, and disturbances in dental development. The results showed no increased caries experience in children treated with BMT or chemotherapy compared with controls. Children treated with BMT had a significantly lower salivary secretion rate of 0.7 +/- 0.4 ml/min, compared with 1.1 +/- 0.5 in the chemotherapy group, and 1.3 +/- 0.6 in the control group (P < 0.05). The clinical examination showed equal numbers of teeth affected by disturbances in enamel mineralization in the BMT and chemotherapy groups. A mean 15.9 +/- 8.2 teeth were affected by disturbances in root development in the BMT group compared with 1.2 +/- 1.6 in the chemotherapy group (P < 0.001). The results show that children who are long-term survivors of pediatric malignant diseases exhibit a wide range of disturbances in the oral cavity. In this study the most severe disturbances are found in children treated with total body irradiation prior to BMT.