title: Peri-implantitis - onset and pattern of progression.
abstract: BACKGROUND
  While information on the prevalence of peri-implantitis is available, data describing onset and progression of the disease are limited.
  
  
  METHODS
  A 9-year follow-up examination of 596 randomly selected implant-carrying individuals identified 62 patients with moderate/severe peri-implantitis. Longitudinal assessments of peri-implant marginal bone levels were used to construct a statistical model with bone loss as the dependent variable. A multilevel growth model estimated the pattern of bone loss for each implant/patient. Onset of peri-implantitis was determined by evaluating the cumulative percentage of implants/patients presenting with estimated bone loss at each year following prosthesis delivery.
  
  
  RESULTS
  The analysis showed a non-linear, accelerating pattern of bone loss at the 105 affected implants. The onset of peri-implantitis occurred early, and 52% and 66% of implants presented with bone loss of >0.5 mm at years 2 and 3 respectively. A total of 70% and 81% of subjects presented with ≥1 implants with bone loss of >0.5 mm at years 2 and 3 respectively.
  
  
  CONCLUSIONS
  It is suggested that peri-implantitis progresses in a non-linear, accelerating pattern and that, for the majority of cases, the onset occurs within 3 years of function.
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: Derks
authors.affiliation: Department of Periodontology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Dennis
authors.initials: D
authors.lastname: Schaller
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: Håkansson
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
authors.affiliation: Department of Periodontology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Cristiano
authors.identifier: http://orcid.org/0000-0002-3610-6574
authors.initials: C
authors.lastname: Tomasi
authors.affiliation: Department of Periodontology, Institute of Odontology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
authors.forename: Tord
authors.initials: T
authors.lastname: Berglundh
mesh_terms: D000368:Aged; D016301:Alveolar Bone Loss; D015921:Dental Implants; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D057873:Peri-Implantitis / Q000453:epidemiology
chemical_list: D015921:Dental Implants
keywords: bone loss; complications; disease progression; onset; peri-implantitis