title: Retrospective analysis of 56 edentulous dental arches restored with 344 single-stage implants using an immediate loading fixed provisional protocol: statistical predictors of implant failure.
abstract: OBJECTIVE
  The purpose of this retrospective study was to evaluate the effects of implant dimensions, surface treatment, location in the dental arch, numbers of supporting implant abutments, surgical technique, and generally recognized risk factors on the survival of a series of single-stage Straumann dental implants placed into edentulous arches using an immediate loading protocol.
  
  
  METHODS
  Each patient received between 4 and 18 implants in one or both dental arches. Periapical radiographs were obtained over a 2- to 10-year follow-up period to evaluate crestal bone loss following insertion of the definitive metal-ceramic fixed prostheses. Univariate tests for failure rates as a function of age (< or = 59 years versus > or = 60 years), gender, smoking, bone grafting, dental arch, surface type, anterior versus posterior, number of implants per arch, and surgical technique were made using Fisher exact tests. The Cochran-Armitage test for trend was used to evaluate the presence of a linear trend in failure rates regarding implant length and implant diameter. Logistic regression modeling was used to determine which, if any, of the aforementioned factors would predict patient and implant failure. A significance criterion of P = .05 was utilized.
  
  
  RESULTS
  Data were collected for 344 single-stage implants placed into 56 edentulous arches (39 maxillae and 17 mandibles) of 43 patients and immediately loaded with a 1-piece provisional fixed prosthesis. A total of 16 implants failed to successfully integrate, for a survival rate of 95.3%. Increased rates of failure were associated with reduced implant length, placement in the posterior region of the jaw, increased implant diameter, and surface treatment. Implant length emerged as the sole significant predictor of implant failure.
  
  
  CONCLUSIONS
  In this retrospective analysis of 56 consecutively treated edentulous arches with multiple single-stage dental implants loaded immediately, reduced implant length was the sole significant predictor of failure.
authors.affiliation: Department of Restorative Dentistry, Division of Prosthodontics and Director, Implant Dentistry Program, Buchanan Dental Center, University of California, San Francisco 94404, USA. drcycle@aol.com
authors.forename: Richard P
authors.initials: RP
authors.lastname: Kinsel
authors.forename: Mindy
authors.initials: M
authors.lastname: Liss
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D016025:Bone Transplantation; D000044:Dental Abutments; D003724:Dental Arch / Q000000981:diagnostic imaging / Q000601:surgery*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003779:Denture Design; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging / Q000534:rehabilitation / Q000601:surgery*; D008297:Male; D016876:Metal Ceramic Alloys; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking
chemical_list: D015921:Dental Implants; D016876:Metal Ceramic Alloys