title: Survival of dental implants in native and grafted bone in irradiated head and neck cancer patients: a retrospective analysis.
abstract: OBJECTIVE
  To study the long-term survival of dental implants placed in native or grafted bone in irradiated bone in subjects who had received radiation for head and neck cancer.
  
  
  METHODS
  A retrospective chart review was conducted for all patients who received dental implants following radiation treatment for head and neck cancer between May 1, 1987 and July 1, 2008. Only patients irradiated with a radiation dose of 50 Gy or greater and those who received dental implants in the irradiated field after head and neck radiation were included in the study. The associations between implant survival and patient/implant characteristics were estimated by fitting univariate marginal Cox proportional hazards models.
  
  
  RESULTS
  A total of 48 patients who had prior head and neck radiation had 271 dental implants placed during May 1987-July 2008. There was no statistically significant difference between implant failure in native and grafted bone (P=0.76). Survival of implants in grafted bone was 82.3% and 98.1% in maxilla and mandible, respectively, after 3 years. Survival of implants in native bone in maxilla and mandible was 79.8% and 100%, respectively, after 3 years. For implants placed in the native bone, there was a higher likelihood of failure in the maxilla compared to the mandible and there was also a tendency for implants placed in the posterior region to fail compared to those placed in the anterior region.
  
  
  CONCLUSIONS
  There was no significant difference in survival when implants were placed in native or grafted bone in irradiated head and neck cancer patients. For implants placed in native bone, survival was significantly influenced by the location of the implant (maxilla or mandible, anterior or posterior).
authors.affiliation: Private Practitioner, Seattle WA, USA. arvimayo@yahoo.com
authors.forename: Aravind
authors.initials: A
authors.lastname: Buddula
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Assad
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Salinas
authors.forename: Yolanda I
authors.initials: YI
authors.lastname: Garces
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016025:Bone Transplantation / Q000379:methods*; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy; D003724:Dental Arch / Q000528:radiation effects / Q000601:surgery; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007568:Jaw / Q000528:radiation effects*; D008297:Male; D008334:Mandible / Q000528:radiation effects / Q000601:surgery; D008437:Maxilla / Q000528:radiation effects / Q000601:surgery; D008875:Middle Aged; D056948:Orthognathic Surgical Procedures; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis
chemical_list: D015921:Dental Implants