title: Attributable fractions, modifiable risk factors and risk stratification using a risk score for peri-implant pathology.
abstract: OBJECTIVE
  This study aimed to estimate the impact of risk factors for peri-implant pathology, to identify potentially modifiable factors, and to evaluate the accuracy of the risk algorithm, risk scores and risk stratification.
  
  
  METHODS
  This retrospective case-control study with 1275 patients (255 cases; 1020 controls) retrieved a model according to the predictors: history of Periodontitis, bacterial plaque, bleeding, bone level, lack of passive fit or non-optimal screw joint, metal-ceramic restoration, proximity to other implants/teeth, and smoking habits. Outcome measures were the attributable fraction; the positive and negative likelihood ratios at different disease cut-off points illustrated by the area under the curve statistic.
  
  
  RESULTS
  Six predictors may be modified or controlled directly by either the patient or the clinician, accounting for a reduction in up to 95% of the peri-implant pathology cases. The positive and negative likelihood ratios were 9.69 and 0.13, respectively; the area under the curve was 0.96; a risk score was developed, making the complex statistical model useful to clinicians.
  
  
  CONCLUSIONS
  Based on the results, six predictors for the incidence of peri-implant pathology can be modified to significantly improve the outcome. It was possible to stratify patients per risk category according to the risk score, providing a tool for clinicians to support their decision-making process.
authors.affiliation: Faculty of Medicine, University of Lisbon, Portugal; Malo Clinic Lisbon, Portugal. Electronic address: mignobre@gmail.com.
authors.forename: Miguel
authors.initials: M
authors.lastname: de Araújo Nobre
authors.affiliation: Integrated Clinic or Oral Medicine, Lisbon, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Mano Azul
authors.affiliation: Faculty of Medicine, University of Lisbon, Portugal.
authors.forename: Evangelista
authors.initials: E
authors.lastname: Rocha
authors.affiliation: Malo Clinic Lisbon, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Maló
authors.affiliation: Faculty of Medicine, University of Lisbon, Portugal.
authors.forename: Francisco
authors.initials: F
authors.lastname: Salvado
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D003757:Dental Implantation / Q000009:adverse effects*; D015921:Dental Implants / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D057873:Peri-Implantitis / Q000209:etiology; D012189:Retrospective Studies; D012306:Risk; D012307:Risk Factors
chemical_list: D015921:Dental Implants
keywords: Dental implants; Pathology; Peri-implant pathology; Peri-implantitis; Risk factors; Risk prediction; Risk scores