title: 120 infrabony defects treated with regenerative therapy: long-term results.
abstract: BACKGROUND
  The aim of this study is to evaluate the long-term benefits of regenerative therapy and which factors (i.e., smoking, oral hygiene, radiographic angle, tooth, clinical center, and biomaterial) influence results.
  
  
  METHODS
  A total of 120 infrabony defects were treated with guided tissue regeneration using bioabsorbable and non-resorbable membranes with grafts or enamel matrix derivative (EMD) proteins. At baseline, smoking, x-ray angle, probing depth (PD), recession, and clinical attachment level (CAL) were recorded. CAL was measured 1 year post-surgery and every 2 years for ≤16 years. The participation of patients in oral hygiene protocols was recorded.
  
  
  RESULTS
  The mean ± SD baseline CAL was 8.5 ± 2.3 mm, baseline PD was 7.8 ± 2.1 mm, and baseline x-ray angle was 31.8° ± 8.9°. One year post-surgery, CAL gain was 4.1 ± 2.1 mm. EMD was used in 47 defects, bioabsorbable membranes with deproteinized bovine bone were used in 41 cases, non-resorbable membranes were used in seven defects, bioabsorbable membranes and autogenous bone were used in five defects, and a combination was used in 20 defects. A total of 10% of subjects were smokers, and 20% of subjects did not participate in an oral hygiene program. The average follow-up was 9 years. A total of 90% teeth survival was achieved at 13 years, and CAL gain was maintained at 82% for 11 years. Statistical analyses demonstrated that smoking and oral hygiene maintenance influenced long-term outcomes. The x-ray angle, tooth, clinical center, and biomaterials did not influence results.
  
  
  CONCLUSIONS
  Regenerative therapy provided a high percentage of long-term success. Smoking and non-participation in oral hygiene maintenance negatively influenced the prognosis, whereas other factors did not affect long-term results.
authors.affiliation: Unit of Periodontology, Department of Surgical, Reconstructive, and Diagnostic Sciences, University of Milan, Foundation IRCCS Cà Granda, Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Silvestri
authors.forename: Giulio
authors.initials: G
authors.lastname: Rasperini
authors.forename: Stefano
authors.initials: S
authors.lastname: Milani
mesh_terms: D020341:Absorbable Implants; D000328:Adult; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000601:surgery*; D001672:Biocompatible Materials / Q000627:therapeutic use; D018786:Bone Substitutes / Q000627:therapeutic use; D016025:Bone Transplantation; D003746:Dental Enamel Proteins / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D005889:Gingival Recession / Q000601:surgery; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D009910:Oral Hygiene; D017622:Periodontal Attachment Loss / Q000601:surgery; D010514:Periodontal Pocket / Q000601:surgery; D011379:Prognosis; D011859:Radiography; D012907:Smoking; D016388:Tooth Loss / Q000209:etiology; D016896:Treatment Outcome
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D003746:Dental Enamel Proteins; D008567:Membranes, Artificial; C109069:enamel matrix proteins