title: Survival and complication rates of fixed restorations supported by locking-taper implants: a prospective study with 1 to 10 years of follow-up.
abstract: OBJECTIVE
  The aim of this 10-year follow-up study was to evaluate the implant survival and complication rates of fixed restorations supported by locking-taper implants.
  
  
  METHODS
  Over a 10-year period (January 2002 to December 2011) all patients referred to a single private practice for treatment with fixed restorations (single crowns, SCs; fixed partial prostheses, FPPs; fixed full arches, FFAs) supported by dental implants were considered for inclusion in the study. At each annual follow-up session, clinical, radiographic, and prosthetic parameters were assessed. The surviving implant-supported restorations were defined as "complication free" in the absence of any biological or prosthetic (mechanical or technical) complication. The cumulative implant survival and the "complication-free" survival of fixed implant-supported restorations were identified using the Kaplan-Meier method. The Log-rank test was used to identify correlations between the study variables.
  
  
  RESULTS
  In total, 1494 locking-taper implants (727 maxilla, 767 mandible) were placed in 642 patients (356 males, 286 females). Nineteen implants (12 maxilla, 7 mandible) failed. Implant failures were attributed to lack of osseointegration (14 implants), peri-implantitis (4 implants), and mechanical overloading (1 implant). An overall 10-year cumulative implant survival rate of 98.7% (98.3% maxilla, 99.1% mandible) was found. The implant survival rates did not significantly differ with respect to implant location, position, bone type, implant length and diameter, and type of restorations. Among the surviving implant-supported restorations (478 SC, 242 FPP, 19 FFA), a few biological (11/739: 1.4%) and prosthetic (27/739: 3.6%) complications were reported. The incidence of mechanical complications was low (3/739: 0.4%), with three loosened abutments in three SCs (3/478: 0.6%), and no abutment fractures; technical complications were more frequent (24/739: 3.2%), with an incidence of decementation of 2.0% (SC 2.0%, FPP 1.6%, FFA 5.2%) and ceramic/veneer chipping/fracture of 1.2% (SC 0.0%, FPP 2.8%, FFA 10.5%). A 10-year cumulative "complication-free" survival of restorations of 88.6% (SC 91.7%, FPP 83.1%, FFA 73.8%) was reported. The complication rates differ significantly with respect to the type of restoration (p < 0.05).
  
  
  CONCLUSIONS
  Fixed restorations on locking-taper implants seem to be a successful procedure for the rehabilitation of partially and completely edentulous arches.
authors.affiliation: Private Practice, Gravedona, Como, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Mangano
authors.forename: Aldo
authors.initials: A
authors.lastname: Macchi
authors.forename: Alberto
authors.initials: A
authors.lastname: Caprioglio
authors.forename: Rachel Lilian
authors.initials: RL
authors.lastname: Sammons
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
authors.forename: Carlo
authors.initials: C
authors.lastname: Mangano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002484:Cementation; D003442:Crowns; D000044:Dental Abutments; D015921:Dental Implants; D019250:Dental Implants, Single-Tooth; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003801:Dental Veneers; D003781:Denture Retention; D003824:Denture, Complete; D003830:Denture, Partial, Fixed; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016348:Osseointegration / Q000502:physiology; D057873:Peri-Implantitis / Q000209:etiology; D011446:Prospective Studies; D013314:Stress, Mechanical; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D015921:Dental Implants
keywords: Implant survival; Morse taper connection implants; mechanical complications; technical complications