Formation and resolution of ankylosis under application of recombinant human bone morphogenetic protein-2 (rhBMP-2) to class III furcation defects in cats.
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.
Takahashi
D
D
Department of Oral Functional Science, Hokkaido University Graduate School of Dental Medicine, Hokkaido, Japan. bmp2@den.hokudai.ac.jp
Odajima
T
T
Morita
M
M
Kawanami
M
M
Kato
H
H
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*
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