Fig. 1.

Mandible bone Dose–volume histograms (mean values, cc) of the following subgroups, all with the mandible exposed to > 60 Gy (n total = 458): -Postoperative IMRT in oral cavity cancer (OCC) patients with/without osteoradionecrosis (±ORN) who underwent mandibular surgery (+MS) or not (−MS) -Definitive IMRT in OCC patients (no MS, all in the cohort without ORN) -Definitive and postoperative IMRT in mesopharynx cancer (MC) patients ± ORN (none of them underwent mandibular surgery). Red curves represent the two cohorts with ORN (+ORN), dotted lines postoperative IMRT groups, and continuous lines definitive IMRT groups