title: Two-year clinical results following treatment of peri-implantitis lesions using a nanocrystalline hydroxyapatite or a natural bone mineral in combination with a collagen membrane.
abstract: OBJECTIVE
  The aim of the present case series was to evaluate the 2-year results obtained following treatment of peri-implantitis lesions using either a nanocrystalline hydroxyapatite (NHA) or a natural bone mineral in combination with a collagen membrane (NBM+CM).
  
  
  METHODS
  Twenty-two patients suffering from moderate peri-implantitis (n=22 intra-bony defects) were randomly treated with (i) access flap surgery (AFS) and the application of NHA, or with AFS and the application of NBM+CM. Clinical parameters were recorded at baseline and after 12, 18, and 24 months of non-submerged healing.
  
  
  RESULTS
  Two patients from the NHA group were excluded from the study due to severe pus formation at 12 months. At 24 months, both groups revealed clinically important probing depth (PD) reductions (NHA: 1.5+/-0.6 mm; NBM+CM: 2.4+/-0.8 mm) and clinical attachment level (CAL) gains (NHA: 1.0+/-0.4 mm; NBM+CM: 2.0+/-0.8 mm). However, these clinical improvements seemed to be better in the NBM+CM group (difference between groups: PD reduction: 0.9+/-0.2 mm; CAL gain: 1.0+/-0.3 mm).
  
  
  CONCLUSIONS
  Both treatment procedures have shown efficacy over a period of 24 months, however, the application of NBM+CM may result in an improved outcome of healing.
authors.affiliation: Department of Oral Surgery, Westdeutsche Kieferklinik, Heinrich Heine University, Düsseldorf, Germany. Frank.Schwarz@med.uni-duesseldorf.de
authors.forename: Frank
authors.initials: F
authors.lastname: Schwarz
authors.forename: Anton
authors.initials: A
authors.lastname: Sculean
authors.forename: Katrin
authors.initials: K
authors.lastname: Bieling
authors.forename: Daniel
authors.initials: D
authors.lastname: Ferrari
authors.forename: Daniel
authors.initials: D
authors.lastname: Rothamel
authors.forename: Jürgen
authors.initials: J
authors.lastname: Becker
mesh_terms: D018786:Bone Substitutes / Q000627:therapeutic use*; D003758:Dental Implantation, Endosseous / Q000009:adverse effects; D015921:Dental Implants / Q000009:adverse effects*; D017886:Durapatite / Q000627:therapeutic use*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008903:Minerals / Q000627:therapeutic use*; D053758:Nanoparticles / Q000627:therapeutic use; D010518:Periodontitis / Q000000981:diagnostic imaging / Q000209:etiology / Q000628:therapy*; D011859:Radiography; D012907:Smoking / Q000009:adverse effects; D016896:Treatment Outcome
chemical_list: C077540:Bio-Oss; D018786:Bone Substitutes; D015921:Dental Implants; D008903:Minerals; D017886:Durapatite