Impact of rhBMP-2 on regeneration of buccal alveolar defects during the osseointegration of transgingival inserted implants.
OBJECTIVE
New approaches to enhance vertical bone regeneration in clinically relevant implant models are needed. Therefore, we analyzed the impact of recombinant human bone morphogenic protein 2 (rhBMP-2) on the healing of large buccal alveolar defects during osseointegration of transgingivally inserted implants.


METHODS
Twenty-four dental implants were inserted transgingivally in the mandibles of 6 labrador/golden retriever cross-bred dogs. Before implantation, a standardized buccal bone defect was created and refilled with either calcium phosphate as a carrier containing rhBMP-2 or calcium phosphate alone. Either ceramic abutments that enabled immediate implant loading or healing distance collars to prevent loading were mounted. Sixteen weeks after intervention, bone implant units were analyzed by radiofrequency analysis and histomorphometry.


RESULTS
In total, 14 implants (58.3%) were available for further analysis. The mean depth of the bone defects, the gain of regenerated bone, the vertical osseointegration of the implants, and the bone-to-implant contact in the newly formed bone were slightly greater in the rhBMP-2-containing samples. In contrast, the osseointegration in the preexisting bone was even superior within the non-rhBMP-2-treated specimen. However no differences were statistically significant.


CONCLUSIONS
When rhBMP-2-conducted bone regeneration was compared with control samples, no significant differences of newly formed bone were found at the bone-implant interface. The amounts of rhBMP-2 applied do not seem suitable to enhance implant osseointegration in large buccal defects.
Smeets
Ralf
R
Department of Oral and Maxillofacial Surgery, University Hospital Aachen, Aachen, Germany. rasmeets@ukaachen.de
Maciejewski
Oliver
O
Gerressen
Markus
M
Spiekermann
Hubertus
H
Hanisch
Oliver
O
Riediger
Dieter
D
Blake
Felix
F
Stein
Jamal
J
Hölzle
Frank
F
Kolk
Andreas
A
D016301:Alveolar Bone Loss / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D000818:Animals; D001857:Bone Matrix / Q000473:pathology; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects*; D002130:Calcium Phosphates; D002516:Ceramics / Q000737:chemistry; D000044:Dental Abutments; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D004285:Dogs; D004337:Drug Carriers; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology / Q000601:surgery; D008336:Mandibular Diseases / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D016348:Osseointegration / Q000502:physiology*; D010006:Osteoblasts / Q000473:pathology; D010012:Osteogenesis / Q000502:physiology; D011994:Recombinant Proteins / Q000627:therapeutic use*; D013499:Surface Properties; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*
D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D002130:Calcium Phosphates; D015921:Dental Implants; D003764:Dental Materials; D004337:Drug Carriers; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; C020243:calcium phosphate