Impact of radiation and chemotherapy on risk of dental abnormalities: A report from the childhood cancer survivor study

BACKGROUND: The current study was performed to describe frequencies and risk factors of altered oral health and odontogenesis in childhood cancer survivors. METHODS: In total, 9308 survivors who were diagnosed between 1970 and 1986 and 2951 siblings from the Childhood Cancer Survivor Study completed a survey that contained oral-dental health information. The authors analyzed treatment impact, socioeconomic data, and patient demographics on dental outcomes using univariate and multivariate logistic regression models to estimate odds ratios (ORs). RESULTS: In multivariate analysis, survivors were more likely to report microdontia (OR, 3.0; 95% confidence interval [95% CI], 2.4-3.8), hypodontia (OR, 1.7; 95% CI, 1.4-2.0), root abnormalities (OR, 3.0; 95% CI, 2.2-4.0), abnormal enamel (OR, 2.4; 95% CI, 2.0-2.9), teeth loss ≥6 (OR, 2.6; 95% CI, 1.9-3.6), severe gingivitis (OR, 1.2; 95% CI, 1.0-1.5), and xerostomia (OR, 9.7; 95% CI, 4.8-19.7). Controlling for chemotherapy and socioeconomic factors, radiation exposure of ≥20 Gray to dentition was associated significantly with an increased risk of ≥1 dental abnormality. Dose-dependent alkylating agent therapy significantly increased the risk of ≥1 anatomic/developmental dental abnormalities in survivors who were diagnosed at age <5 years (OR, 1.7, 2.7, and 3.3 for alkylating agent scores of 1, 2, and 3, respectively). CONCLUSIONS: Radiation and chemotherapy were independent risk factors for adverse oral-dental sequelae among childhood cancer survivors. The authors concluded that patients who received receiving alkylating agents at age <5 years should be closely monitored.