Prospectively-collected, tooth-specific dosimetry correlated with adverse dental outcomes.

OBJECTIVES: To correlate radiation dose to specific tooth-bearing portions of bone with adverse dental outcomes. STUDY DESIGN: Eighty-nine patients treated with intensity-modulated radiation therapy with or without chemotherapy had radiation dose to specific tooth-bearing portions of the mandible and the maxilla. Data were collected prospectively during treatment planning, which resulted in 2490 data points. These patients underwent a comprehensive dental intake evaluation that included measurement of pocket depths and were then followed up with serial dental evaluations for a median of 2.5 years (range 0.2-6.9 years). RESULTS: At the patient level, the 3-year risks of osteoradionecrosis (ORN) and periodontal disease were 2.5% and 36.6%, respectively. For any individual tooth, the risks of ORN and periodontal disease were 0.1% and 5.1%, respectively, at 3 years. Radiation dose to individual tooth-bearing portions of bone was correlated with ORN development (P = .0165). Periodontal disease also demonstrated a significant, but more gradual, dose response (P = .0395). CONCLUSIONS: Adverse dental outcomes directly correlate with increased tooth-specific doses.