@misc{oai:repo.qst.go.jp:00071115,
 author = {Ikawa, Hiroaki and Sasahara, Go and Takagi, Ryo and Koto, Masashi and Hasegawa, Azusa and Tsuji, Hiroshi and Kamada, Tadashi and 伊川 裕明 and 佐々原 剛 and 高木 亮 and 小藤 昌志 and 長谷川 安都佐 and 辻 比呂志 and 鎌田 正},
 month = {May},
 note = {Purpose: The aim of this study is to evaluate the incident of maxillary osteoradionecrosis (ORN) in patients who underwent carbon ion radiotherapy (CIRT) for head and neck cancer.
Materials and Methods: From April 1997 to April 2006, 239 patients with the head and neck cancers were treated with CIRT with a dose of 57.6 GyE per 16 fractions. Patients whose alveolar process and palatine process of maxilla had been irradiated more than 10 percent of the prescribed dose were selected. We retrospectively investigated the incidence and treatment of ORN. 
Results: Sixty seven patients were enrolled in this study. Of the 67 patients, 33 patients (49.3%) developed ORN. Sixteen patients (23.9%) received no treatment, 13 patients (19.4%) with exposed sequestrum received conservative therapy. Four patients (6.0%) with failure of conservative therapy were undergone sequestrectomy.
After sequestrectomy, all of 4 patients showed no signs of sequestrum re-exposure or symptom exacerbation during the average follow up period of 36.7 months (range, 4-58 months). In addition, masticatory function was maintained using dento-maxillary prosthesis in all cases.
Conclusions: Although 33 patients developed ORN, only 4 patients needed the surgical treatment. However we could control the clinical symptoms and improved the QOL for the 4 patients after surgical intervention., Heavy Ion in Therapy and Space Radiation Symposium 2013(HITSRS2013)},
 title = {Experience of long-term management for osteoradionecrosis of the maxilla after carbon ion radiotherapy},
 year = {2013}
}