Evaluation of implants coated with recombinant human bone morphogenetic protein-2 and vacuum-dried using the critical-size supraalveolar peri-implant defect model in dogs.
BACKGROUND
Endosseous implants coated with recombinant human bone morphogenetic protein-2 (rhBMP-2) in a laboratory bench setting and air-dried induce relevant bone formation but also resident bone remodeling. Thus, the objective of this study is to evaluate the effect of implants fully or partially coated with rhBMP-2 and vacuum-dried using an industrial process on local bone formation and resident bone remodeling.


METHODS
Twelve male adult Hound Labrador mongrel dogs were used. Critical-size, supraalveolar, peri-implant defects received titanium porous oxide surface implants coated in their most coronal aspect with rhBMP-2 (coronal-load, six animals), or by immersion of the entire implant in a rhBMP-2 solution (soak-load, six animals) for a total of 30 μg rhBMP-2 per implant. All implants were vacuum-dried. The animals were sacrificed at 8 weeks for histometric evaluation.


RESULTS
Clinical healing was unremarkable. Bone formation was not significantly affected by the rhBMP-2 application protocol. New bone height and area averaged (± SE) 3.2 ± 0.5 versus 3.6 ± 0.3 mm, and 2.3 ± 0.5 versus 2.6 ± 0.8 mm(2) for coronal-load and soak-load implants, respectively (P >0.05). The corresponding bone density and bone-implant contact registrations averaged 46.7% ± 5.8% versus 31.6% ± 4.4%, and 28% ± 5.6% versus 36.9% ± 3.4% (P >0.05). In contrast, resident bone remodeling was significantly influenced by the rhBMP-2 application protocol. Peri-implant bone density averaged 72.2% ± 2.1% for coronal-load versus 60.6% ± 4.7% for soak-load implants (P <0.05); the corresponding bone-implant contact averaged 70.7% ± 6.1% versus 47.2% ± 6.0% (P <0.05).


CONCLUSIONS
Local application of rhBMP-2 and vacuum-drying using industrial process seems to be a viable technology to manufacture implants that support local bone formation and osseointegration. Coronal-load implants obviate resident bone remodeling without compromising local bone formation.
Decker
John F
JF
Department of Periodontics, School of Dentistry, Medical College of Georgia, Augusta, GA 30912, USA.
Lee
Jaebum
J
Cortella
Carlo Alberto
CA
Polimeni
Giuseppe
G
Rohrer
Michael D
MD
Wozney
John M
JM
Hall
Jan
J
Susin
Cristiano
C
Wikesjö
Ulf M E
UM
D016301:Alveolar Bone Loss / Q000601:surgery*; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000473:pathology; D000818:Animals; D015519:Bone Density / Q000187:drug effects; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D016723:Bone Remodeling / Q000187:drug effects*; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000627:therapeutic use*; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D017267:Dental Prosthesis Design; D003890:Desiccation; D004285:Dogs; D006801:Humans; D007101:Immersion; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology; D008336:Mandibular Diseases / Q000601:surgery; D016348:Osseointegration / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects*; D011859:Radiography; D011994:Recombinant Proteins / Q000627:therapeutic use*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D020390:Tooth Socket / Q000601:surgery; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*; D014618:Vacuum
D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; C009495:titanium dioxide; D014025:Titanium