title: Comparison of tooth loss between intensity-modulated and conventional radiotherapy in head and neck cancer patients.
abstract: OBJECTIVE
  Advanced radiotherapy (RT) such as intensity-modulated radiotherapy (IMRT) has become more common in the management of head and neck cancer (HNC). IMRT includes focused target volume coverage while sparing salivary tissues to protect function. However, the long-term effects on dentition after IMRT are not well established. This investigation sought to understand dental status by comparing tooth loss after IMRT and conventional RT in HNC patients.
  
  
  METHODS
  A retrospective chart review was conducted on individuals who received IMRT or conventional RT (± surgery, ± chemotherapy) for oropharyngeal, oral cavity, and nasopharyngeal cancer between 2000 and 2010 at the Institute for Reconstructive Sciences in Medicine. Tooth loss, the primary outcome measure, was assessed using intraoral photographs, radiographs, and clinical records. The influence of patient demographics on tooth loss was assessed as well.
  
  
  RESULTS
  Eighty-six patients were eligible for review at baseline; 44 received IMRT and 42 received conventional RT. Twenty-four had data collected up to 2 years after RT. After adjusting for baseline number of teeth, no significant differences were found between groups 2 years after RT using repeated measures analysis of covariance (p  =  .079). The site of disease was significantly different between groups.
  
  
  CONCLUSIONS
  No statistically significant differences in tooth loss between RT groups were found 2 years after RT; however, trends in the data suggest that tooth loss increased each year after RT. The early findings need to be viewed with caution as data beyond 3 to 5 years and a larger sample size are needed to understand the dental effects after advanced RT.
authors.affiliation: Institute for Reconstructive Sciences in Medicine, Covenant Health, University of Alberta, Alberta Health Services. richelle.beesley@albertahealthservices.ca
authors.forename: Richelle
authors.initials: R
authors.lastname: Beesley
authors.forename: Jana
authors.initials: J
authors.lastname: Rieger
authors.forename: Sharon
authors.initials: S
authors.lastname: Compton
authors.forename: Matthew
authors.initials: M
authors.lastname: Parliament
authors.forename: Hadi
authors.initials: H
authors.lastname: Seikaly
authors.forename: Johan
authors.initials: J
authors.lastname: Wolfaardt
mesh_terms: D005260:Female; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D012307:Risk Factors; D016388:Tooth Loss / Q000209:etiology*