title: Complication and failure rates of fixed dental prostheses in patients treated for periodontal disease.
abstract: OBJECTIVE
  to evaluate the biological and technical complication rates of fixed dental prostheses (FDP) with end abutments or cantilever extensions on teeth (FDP-tt/cFDP-tt) on implants (FDP-ii/cFDP-ii) and tooth-implant-supported (FDP-ti/cFDP-ti) in patients treated for chronic periodontitis.
  
  
  METHODS
  from a cohort of 392 patients treated between 1978 and 2002 by graduate students, 199 were re-examined in 2005. Of these, 84 patients had received ceramo-metal FDPs (six groups).
  
  
  RESULTS
  at the re-evaluation, the mean age of the patients was 62 years (36.2-83.4). One hundred and seventy-five FDPs were seated (82 FDP-tt, 9 FDP-ii, 20 FDP-ti, 39 cFDP-tt, 15 cFDP-ii, 10 cFDP-ti). The mean observation time was 11.3 years; 21 FDPs were lost, and 46 technical and 50 biological complications occurred. Chances for the survival of the three groups of FDPs with end abutments were very high (risk for failure 2.8%, 0%, 5.6%). The probability to remain without complications and/or failure was 70.3%, 88.9% and 74.7% in FDPs with end abutments, but 49.8-25% only in FDPs with extensions at 10 years.
  
  
  CONCLUSIONS
  in patients treated for chronic periodontitis and provided with ceramo-metal FDPs, high survival rates, especially for FDPs with end abutments, can be expected. The incidence rates of any negative events were increased drastically in the three groups with extension cFDPs (tt, ii, ti). Strategic decisions in the choice of a particular FDP design and the choice of teeth/implants as abutments appear to influence the risks for complications to be expected with fixed reconstruction. If possible, extensions on tooth abutments should be avoided or used only after a cautious clinical evaluation of all options.
authors.affiliation: School of Dental Medicine, University of Bern, Bern, Switzerland. urs.braegger@zmk.unibe.ch
authors.forename: Urs
authors.initials: U
authors.lastname: Brägger
authors.forename: Stefanie
authors.initials: S
authors.lastname: Hirt-Steiner
authors.forename: Natascha
authors.initials: N
authors.lastname: Schnell
authors.forename: Kurt
authors.initials: K
authors.lastname: Schmidlin
authors.forename: Giovanni E
authors.initials: GE
authors.lastname: Salvi
authors.forename: Bjarni
authors.initials: B
authors.lastname: Pjetursson
authors.forename: Giedre
authors.initials: G
authors.lastname: Matuliene
authors.forename: Marcel
authors.initials: M
authors.lastname: Zwahlen
authors.forename: Niklaus P
authors.initials: NP
authors.lastname: Lang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055113:Chronic Periodontitis / Q000150:complications* / Q000628:therapy; D003442:Crowns; D000044:Dental Abutments; D003731:Dental Caries / Q000209:etiology; D017267:Dental Prosthesis Design / Q000009:adverse effects*; D019094:Dental Prosthesis, Implant-Supported / Q000009:adverse effects*; D019232:Dental Restoration Failure; D003830:Denture, Partial, Fixed / Q000009:adverse effects*; D006801:Humans; D053208:Kaplan-Meier Estimate; D016876:Metal Ceramic Alloys; D008875:Middle Aged; D057873:Peri-Implantitis / Q000209:etiology; D010485:Periapical Periodontitis / Q000209:etiology; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric
chemical_list: D016876:Metal Ceramic Alloys