title: Long-term treatment outcomes in edentulous patients with implant-fixed prostheses: the Toronto study.
abstract: OBJECTIVE
  The aim of this prospective study was to report long-term treatment outcomes (prosthetic and implant related) of edentulous patients treated with implant-supported fixed prostheses who participated in the first clinical implant study in North America.
  
  
  METHODS
  Forty-five patients were treated with Brånemark implants supporting a total of 47 fixed prostheses (42 mandibular and 5 maxillary) between 1979 and 1984. All patients were recalled regularly for comprehensive prospective clinical and radiographic assessments.
  
  
  RESULTS
  Thirty-one patients (33 prostheses) attended a final recall visit in 2002; 71% of patients had been followed for 20 years (range 18 to 23 years), with overall prosthetic plan and implant outcome success rates of 84% and 87%, respectively. Mean marginal bone loss around the implants after the first year of loading was small (0.05 mm/year), with high individual variations. Poor oral hygiene, smoking history, and implant position appeared to be predictors of marginal bone loss. Prosthetic maintenance was ongoing and included fractured components and replacement of prostheses; the longevity of a fixed prosthesis for this group of patients was 8.39+/-5.30 years.
  
  
  CONCLUSIONS
  This study confirmed the overall long-term treatment outcome success of patients treated with fixed prostheses supported by Brånemark implants. Successful osseointegration with a small mean bone loss was maintained as study patients aged, although prosthetic maintenance was required. The latter consideration should be discussed with all patients seeking such treatment.
authors.affiliation: Faculty of Dentistry, University of Toronto, Ontario, Canada. nik.attard@utoronto.ca
authors.forename: Nikolai J
authors.initials: NJ
authors.lastname: Attard
authors.forename: George A
authors.initials: GA
authors.lastname: Zarb
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000209:etiology; D000704:Analysis of Variance; D003758:Dental Implantation, Endosseous / Q000379:methods; D019094:Dental Prosthesis, Implant-Supported / Q000009:adverse effects; D019232:Dental Restoration Failure; D019554:Dental Restoration Wear; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009066:Mouth, Edentulous / Q000534:rehabilitation*; D009864:Ontario; D016348:Osseointegration; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D016896:Treatment Outcome