Risk-adapted dental care prior to intensity-modulated radiotherapy (IMRT).

Background: At the Clinic for Radiation Oncology at the Zurich University Hospital (UniversitätsSpital Zürich [USZ]), head-and-neck tumor (HNT) patients have been treated with intensity-modulated radiotherapy (IMRT) since 01/2002 (n 〉 800). This method causes less damage to normal tissues adjacent to the tumor, and thus it was possible in the head/neck region to markedly reduce the rate of osteoradionecrosis (ORN), in addition to reducing the rate of severe xerostomia. Based on these results, risk-adapted dental care (RaDC) was adopted by our clinic as the standard mode of pre-IMRT dental treatment. The guidelines as formulated by Grötz et al. were respected. ORN prophylaxis is one of the most important goals of pre-radiotherapy dental care, and the ORN rate is a measurable parameter for the efficacy of dental care, given a certain radiation technique. The aim of the present study was therefore to evaluate the efficacy of RaDC as reflected by the ORN rate of our IMRT patients.

Materials and methods: IN August 2006, RaDC was clinically implemented and has been used for all HNT patients prior to IMRT since then. Before that (01/2002-07/2006), dental restorations were performed according to the usual procedure.

Results: The rate of grade-2 ORN was similar in the conventionally treated and RaDC groups (2% and 1%, resp.); grade-3 ORN had not occurred by the time the analysis was conducted. As expected, fewer extractions were performed in the RaDC cohort (no extractions in 47% of the RaDC/IMRT cohort vs. 27% in the IMRT cohort receiving conventional dental care).

Conclusion: After considerably less invasive dental treatment, no higher-grade ORN occurred and no ORN-related jaw resections were required. Based on the present data, risk-adapted minimally invasive dental care is recommended before IMRT.