title: Formation and resolution of ankylosis under application of recombinant human bone morphogenetic protein-2 (rhBMP-2) to class III furcation defects in cats.
abstract: OBJECTIVE
  Periodontal regeneration under application of bone morphogenetic protein (BMP) is compromised by ankylosis. Ankylosis disappearance following application of BMP has been observed in the case of a small defect, which might be beneficial change for periodontal regeneration. However, the histological observation of ankylosis disappearance has not been demonstrated in a large defect. The purpose of this present study was to confirm resolution of ankylosis during periodontal regeneration by recombinant human BMP-2 (rhBMP-2) applied to class III furcation defects.
  
  
  METHODS
  Class III furcation defects were created in the premolars of six adult cats. The rhBMP-2 material, prepared by applying rhBMP-2 to a combination of polylactic acid-polygricolic copolymer and gelatin sponge (PGS; 0.33 microg rhBMP-2/mm(3) PGS) or control material containing only PGS, was implanted into each defect. The cats were killed at 3, 6 or 12 weeks after surgery and serial sections were prepared for histological and histometrical observation.
  
  
  RESULTS
  Ankylosis was observed in some of the rhBMP-2/PGS group at 3 and 6 weeks, but not at 12 weeks. At 6 weeks, osteoclast-like cells were visible in the rhBMP-2/PGS group with ankylosis. Residual PGS was evident between the bone and root surface in the rhBMP-2/PGS group without ankylosis at 3 weeks.
  
  
  CONCLUSIONS
  Resolution of ankylosis by osteoclast-like cells possibly occurred under application of rhBMP-2. Residual PGS might play an important role in preventing ankylosis formation.
authors.affiliation: Department of Oral Functional Science, Hokkaido University Graduate School of Dental Medicine, Hokkaido, Japan. bmp2@den.hokudai.ac.jp
authors.forename: D
authors.initials: D
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Odajima
authors.forename: M
authors.initials: M
authors.lastname: Morita
authors.forename: M
authors.initials: M
authors.lastname: Kawanami
authors.forename: H
authors.initials: H
authors.lastname: Kato
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D001861:Bone Regeneration / Q000187:drug effects*; D002415:Cats; D003739:Dental Cementum / Q000502:physiology; D004337:Drug Carriers; D017823:Furcation Defects / Q000150:complications / Q000601:surgery*; D005780:Gelatin; D006801:Humans; D020007:Implants, Experimental; D019344:Lactic Acid; D008297:Male; D010010:Osteoclasts / Q000187:drug effects* / Q000502:physiology; D010513:Periodontal Ligament / Q000502:physiology; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D011994:Recombinant Proteins / Q000008:administration & dosage; D012038:Regeneration / Q000187:drug effects; D020254:Tooth Ankylosis / Q000188:drug therapy* / Q000209:etiology; D016212:Transforming Growth Factor beta / Q000008:administration & dosage*
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D004337:Drug Carriers; D011108:Polymers; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D005780:Gelatin