Effects of anti-neoplastic therapy on tooth and bone formation : clinical and experimental studies

Long-term dental sequelae after treatment of childhood malignancies were studied in patients treated with chemotherapy and with bone marrow transplantation (BMT) before 12 years of age. Compared to healthy controls, there was no statistically significant difference between the chronological and dental age in children treated with chemotherapy. Dental maturity, measured as dental age, in children with hematological malignancies does not seem to be affected by chemotherapy. There was no increase in caries experience in children treated with chemotherapy or BMT compared to controls. Children treated with BMT had a significantly lower salivary secretion rate. Equal numbers of teeth affected by disturbances in enamel mineralization were recorded in the BMT and chemotherapy groups. Children treated with BMT had significantly more teeth affected by disturbances in root development. Children who are long-term survivors of pediatric malignant diseases exhibit a wide range of disturbances in the oral cavity, and the most severe disturbances occur in children treated with TBI prior to BMT. Evaluation of disturbances in dental development and tooth size was performed in children conditioned with TBI and cyclophosphamide (Cy) prior to BMT, and in children treated with combination chemotherapy. Planimetric measurements of tooth size were made on panoramic radiographs. Children treated with TBI/Cy exhibited a pronounced reduction in tooth size compared to the controls. It was concluded that all developing teeth are affected by combination chemotherapy and radiation therapy and the most severe disturbances occur in children treated with TBI/Cy at an early age. Histological and SEM studies showed that the chemotherapeutic agent cyclophosphamide given to young rats interferes in the process of tooth formation. To some extent these findings could explain the mechanism behind the abnormalities in tooth development seen in children after treatment for malignant disease. The intermaxillary suture in young rats treated with cyclophosphamide exhibited abnormal histology. The growth processes seemed to be impeded, the bony part of the suture was lacking the osteoid layer, and the width of the suture was reduced.