title: Bone formation around zirconia implants combined with rhBMP-2 gel in the canine mandible.
abstract: OBJECTIVE
  The aim of this study was to estimate the effects of zirconia implants and recombinant human bone morphogenetic protein-2 (rhBMP-2) gel on the acceleration of local bone formation and osseointegration in the canine mandible.
  
  
  METHODS
  Four groups of 48 implants with identical geometry were installed in the mandibles of beagle dogs: alumina-blasted zirconia implants applied with rhBMP-2, alumina-blasted zirconia implants applied with demineralized bone matrix (DBM), alumina-blasted zirconia implants, and resorbable blast media-treated titanium (Ti) implants. For the first two groups, zirconia implants were inserted after the surgical sites were filled with rhBMP-2 or DBM gel. For the other two groups, zirconia or Ti implants were installed with no adjunctive treatment. Fluorescent bone markers were administered to monitor bone remodeling at weeks 2, 4, and 5 postimplantation. After healing periods of 3 weeks and 6 weeks, the animals were sacrificed, and fluorescent microscopy, histology, and histomorphometric analyses were performed.
  
  
  RESULTS
  Fluorescent microscopy showed that bone formation around the zirconia implants installed with rhBMP-2 gel was the most prominent at 2 weeks postimplantation, while the Ti implants acquired bone apposition mainly at week 5. No significant differences were found in bone area among the groups (P > 0.05). The zirconia implants showed similar bone-to-implant contact to the Ti implants. There were no significant differences in bone-to-implant contact between the zirconia implants with rhBMP-2 gel and those with DBM (P > 0.05).
  
  
  CONCLUSIONS
  The zirconia implants with alumina-blasted surfaces may achieve osseointegration in much the same manner as the well-established Ti implants. The area influenced by rhBMP-2 gel, including the alveolar crest, may cause active remodeling and early bone formation.
authors.affiliation: Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Korea.
authors.forename: Byung-Chul
authors.initials: BC
authors.lastname: Lee
authors.forename: In-Sung
authors.initials: IS
authors.lastname: Yeo
authors.forename: Dae-Joon
authors.initials: DJ
authors.lastname: Kim
authors.forename: Jai-Bong
authors.initials: JB
authors.lastname: Lee
authors.forename: Sung-Hun
authors.initials: SH
authors.lastname: Kim
authors.forename: Jung-Suk
authors.initials: JS
authors.lastname: Han
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology*; D015921:Dental Implants; D004285:Dogs; D005782:Gels / Q000494:pharmacology; D020007:Implants, Experimental; D008334:Mandible / Q000601:surgery*; D008856:Microscopy, Fluorescence; D016348:Osseointegration / Q000187:drug effects*; D010012:Osteogenesis / Q000187:drug effects*; D011994:Recombinant Proteins / Q000494:pharmacology; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D015040:Zirconium / Q000737:chemistry
chemical_list: D055396:Bone Morphogenetic Protein 2; D015921:Dental Implants; D005782:Gels; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide