title: Implant-supported single-tooth restorations. A 12-year prospective study.
abstract: OBJECTIVE
  The aim of this study was to evaluate prospectively the 12-year outcome of implant-supported single-tooth restorations.
  
  
  METHODS
  Originally 45 self-tapping Astra Tech TiOblast®ST-implants were installed by a two-stage protocol in 40 subjects requiring single-tooth prosthetic replacement for a missing tooth. Clinical and radiologic examinations were performed at completion of the prosthetic treatment 4-7 months after implant installation surgery and after 5 and 12 years in function.
  
  
  RESULTS
  At 12 years 31 patients and 35 implants were available for evaluation. The overall failure rate after 12 years was 10.3% on the subject level and 9.1% on the implant level. The mean bone loss amounted to 0.67 mm (SD 2.20) on a subject level and 0.47 mm (1.72) on an implant level. Three subjects (10%) and three implants (8.6%) were diagnosed with peri-implantitis. Five subjects had experienced technical complications; three incidences of loosening of the abutment retention screw during the first 5 years and two minor porcelain fracture of the crown (two patients) between 5- and 12-years of follow-up.
  
  
  CONCLUSIONS
  The findings reported in this 12-year prospective case series suggest that the use of the Astra Tech dental implants may be a valid treatment alternative for single-tooth replacement prostheses.
authors.affiliation: Department of Periodontology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. mauro.donati@odontologi.gu.se.
authors.forename: Mauro
authors.initials: M
authors.lastname: Donati
authors.affiliation: Department of Oral & Maxillofacial Radiology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Annika
authors.initials: A
authors.lastname: Ekestubbe
authors.affiliation: Department of Periodontology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Jan
authors.initials: J
authors.lastname: Lindhe
authors.affiliation: Department of Periodontology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Jan L
authors.initials: JL
authors.lastname: Wennström
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology; D003758:Dental Implantation, Endosseous; D019250:Dental Implants, Single-Tooth / Q000009:adverse effects; D019232:Dental Restoration Failure; D005260:Female; D006801:Humans; D008297:Male; D008336:Mandibular Diseases / Q000000981:diagnostic imaging; D008439:Maxillary Diseases / Q000000981:diagnostic imaging; D008875:Middle Aged; D057873:Peri-Implantitis; D011446:Prospective Studies; D011859:Radiography; D055815:Young Adult
keywords: bone loss; clinical; dental implants; long-term follow up; radiology