title: Clinical study of a spacer to help prevent osteoradionecrosis resulting from brachytherapy for tongue cancer.
abstract: OBJECTIVE
  We sought to describe a simple method to construct a spacer and to evaluate with the use of computed tomography the spacer's effectiveness in preventing osteoradionecrosis of the mandible.
  
  
  METHODS
  Fifty-three patients with oral tongue cancers who were treated by means of interstitial brachytherapy were included in this study. Patients underwent a computed tomography examination immediately after the implantation of radioactive sources, with the spacers in place. Distances between the radioactive sources and the lingual surfaces of the mandible were measured on transverse computed tomographs and were evaluated in terms of the development of osteoradionecrosis in the mandible.
  
  
  RESULTS
  Statistically significant differences in the frequency of osteoradionecrosis were observed between patients who had received spacers equal to or thicker than 5 mm and those who had received spacers less than 5 mm thick.
  
  
  CONCLUSIONS
  A spacer should have a minimum thickness of 5 mm on its lingual flange to prevent the development of osteoradionecrosis of the mandible.
authors.affiliation: Division of Oral and Maxillofacial Disorders, Hokkaido University Dental Hospital, Sapporo, Japan. obinata@den.hokudai.ac.jp
authors.forename: Kenichi
authors.initials: K
authors.lastname: Obinata
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ohmori
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Tuchiya
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishioka
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shirato
authors.forename: Motoyasu
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging; D008336:Mandibular Diseases / Q000209:etiology / Q000517:prevention & control*; D008875:Middle Aged; D010025:Osteoradionecrosis / Q000209:etiology / Q000517:prevention & control*; D011482:Protective Devices; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014062:Tongue Neoplasms / Q000532:radiotherapy*