title: Risk indicators related to peri-implant disease: an observational retrospective cohort study.
abstract: OBJECTIVE
  The aim of the present study was to retrospectively investigate the influence of potential risk indicators on the development of peri-implant disease.
  
  
  METHODS
  Overall, 103 patients referred for implant treatment from 2000 to 2012 were randomly enrolled. The study sample consisted of 421 conventional-length (>6 mm) non-turned titanium implants that were evaluated clinically and radiographically according to pre-established clinical and patient-related parameters by a single investigator. A non-parametric Mann-Whitney U test or Kruskal-Wallis rank test and a logistic regression model were used for the statistical analysis of the recorded data at the implant level.
  
  
  RESULTS
  The diagnosis of peri-implant mucositis and peri-implantitis was made for 173 (41.1%) and 19 (4.5%) implants, respectively. Age (≥65 years), patient adherence (professional hygiene recalls <2/year) and the presence of plaque were associated with higher peri-implant probing-depth values and bleeding-on-probing scores. The logistic regression analysis indicated that age (P=0.001), patient adherence (P=0.03), the absence of keratinized tissue (P=0.03), implants placed in pristine bone (P=0.04), and the presence of peri-implant soft-tissue recession (P=0.000) were strongly associated with the event of peri-implantitis.
  
  
  CONCLUSIONS
  Within the limitations of this study, patients aged ≥65 years and non-adherent subjects were more prone to develop peri-implant disease. Therefore, early diagnosis and a systematic maintenance-care program are essential for maintaining peri-implant tissue health, especially in older patients.
authors: Implant Center for Edentulism and Jawbone Atrophies, Maxillofacial Surgery and Odontostomatology Unit, IRCCS Cà Granda Foundation Maggiore Policlinico Hospital, University of Milan, Milan, Italy .
authors: Pier Paolo
authors: 0000-0003-3739-1490
authors: PP
authors: Poli
authors: Implant Center for Edentulism and Jawbone Atrophies, Maxillofacial Surgery and Odontostomatology Unit, IRCCS Cà Granda Foundation Maggiore Policlinico Hospital, University of Milan, Milan, Italy .
authors: Mario
authors: 0000-0002-2223-2553
authors: M
authors: Beretta
authors: Implant Center for Edentulism and Jawbone Atrophies, Maxillofacial Surgery and Odontostomatology Unit, IRCCS Cà Granda Foundation Maggiore Policlinico Hospital, University of Milan, Milan, Italy .
authors: Giovanni Battista
authors: 0000-0003-3367-0679
authors: GB
authors: Grossi
authors: Implant Center for Edentulism and Jawbone Atrophies, Maxillofacial Surgery and Odontostomatology Unit, IRCCS Cà Granda Foundation Maggiore Policlinico Hospital, University of Milan, Milan, Italy .
authors: Carlo
authors: 0000-0001-8748-9483
authors: C
authors: Maiorana
keywords: Dental implants; Implant-supported dental prosthesis; Peri-implantitis; Periodontal diseases; Retrospective study; Risk factors