title: Outcome of dental implants in patients with and without a history of periodontitis: a 5-year pragmatic multicentre retrospective cohort study of 1727 patients.
abstract: OBJECTIVE
  To evaluate the outcome of dental implants placed in patients with a history of periodontitis. Patients with no or mild history of periodontitis served as controls.
  
  
  METHODS
  A total of 1727 patients were consecutively treated in four private practices. Patients were divided into three groups according to their initial periodontal conditions assessed with a modified periodontal screening and recording (PSR) index: 630 patients were in the severe periodontitis (SP) group, 839 in the moderate periodontitis (MP) group, and 258 had no periodontitis (NP). Patients requiring periodontal treatment were treated prior to implantation. Various implant systems and procedures were used. In total, 3260 implants and 1707 implant-supported prostheses were placed in the SP group, 2813 implants and 1744 implant-supported prostheses in the MP group, and 647 implants and 424 implant-supported prostheses in the NP group. Mixed implant–tooth supported prostheses (98 prostheses in 89 patients) were not considered. Outcome measures were prosthesis and implant survival.
  
  
  RESULTS
  Two-hundred and fifty patients were lost to follow-up 5 years after loading. Regarding prosthesis failures, 13 prostheses could not be placed or failed in 13 patients of the SP group (0.8%), 11 prostheses could not be placed or failed in 9 patients of the MP group (0.7%), and 3 prostheses failed in 3 patients of the NP group (0.9%). For implant failures, 130 (4.5%) implants failed in the SP group, 74 (3.1%) implants failed in the MP group, and 15 (3.0%) implants failed in the NP group. Most of the implant failures (90%) occurred before implant loading. Fitting a logistic regression for early implant failures and total implant failures, taking into account the clustering of implants in patients, there were no statistically significant differences between the three PSR groups (P > 0.05).
  
  
  CONCLUSIONS
  Owing to the retrospective nature of this study, conclusions need to be interpreted with caution. A previous history of periodontal disease may not have a significant impact on implant failures up to 5 years after loading.
authors.affiliation: Department of Biomaterials, The Sahlgrenska Academy at Göteborg University, Sweden.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Gianserra
authors.forename: Raffaele
authors.initials: R
authors.lastname: Cavalcanti
authors.forename: Francesco
authors.initials: F
authors.lastname: Oreglia
authors.forename: Massimo Francesco
authors.initials: MF
authors.lastname: Manfredonia
authors.forename: Marco
authors.initials: M
authors.lastname: Esposito
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D000044:Dental Abutments / Q000706:statistics & numerical data; D003758:Dental Implantation, Endosseous / Q000706:statistics & numerical data; D015921:Dental Implants / Q000706:statistics & numerical data*; D019094:Dental Prosthesis, Implant-Supported / Q000706:statistics & numerical data; D019232:Dental Restoration Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D010518:Periodontitis / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015921:Dental Implants