title: The effect of keratinized mucosa width on peri-implant outcome under supportive postimplant therapy.
abstract: BACKGROUND
  Long-ranging data on the influence of keratinized mucosa (KM) on peri-implant tissue status have been scarce.
  
  
  OBJECTIVE
  Retrospective evaluation of peri-implant diseases and KM width in patients with versus without mucogingival surgery.
  
  
  METHODS
  Under supportive postimplant therapy (SIT) in a private practice, 68 patients with peri-implant KM widths <1 mm were identified between 1992 and 2011 (eight dropouts). Thirty patients rejected surgery (control [C] group), and 30 patients agreed (intervention [I] group). After at least 1 year, KM width, mucositis, and peri-implant conditions were assessed.
  
  
  RESULTS
  Sixty nonsmoking patients (n = 105 implants) were available for assessment after 12.10 ± 4.93 years. No implants were lost (survival rate: 100%). An average of 10.69 years after surgery, the I group implants showed a mean KM gain of 3.10 ± 1.43 mm (C group: 0 mm). The mucositis rates were as follows: I group: 38.98%; C group: 31.91%. Peri-implantitis was detected in two implants (1.87%) and two individuals (6.67%) in the I group. No significant differences between groups were found, except that the KM width values were significantly greater in the I group (p < 0.001).
  
  
  CONCLUSIONS
  Low incidences of peri-implant diseases over long periods can be expected in patients attending SIT programs, independent of the absence or presence of KM.
authors.forename: Eberhard
authors.initials: E
authors.lastname: Frisch
authors.forename: Dirk
authors.initials: D
authors.lastname: Ziebolz
authors.forename: Kirstin
authors.initials: K
authors.lastname: Vach
authors.forename: Petra
authors.initials: P
authors.lastname: Ratka-Krüger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015921:Dental Implants / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000473:pathology; D052016:Mucositis / Q000209:etiology / Q000473:pathology / Q000628:therapy*; D057873:Peri-Implantitis / Q000209:etiology / Q000473:pathology / Q000628:therapy*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D015921:Dental Implants
keywords: connective tissue graft; dental implant; free gingival graft; keratinized mucosa; long-term results; maintenance; peri-implant mucositis; peri-implantitis