Bone reconstruction following implantation of rhBMP-2 and guided bone regeneration in canine alveolar ridge defects.
BACKGROUND
Alveolar ridge aberrations commonly require bone augmentation procedures for optimal placement of endosseous dental implants. The objective of this study was to evaluate local bone formation following implantation of recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier with or without provisions for guided bone regeneration (GBR) as potential treatment modalities for alveolar augmentation.


METHODS
Surgically induced, large, mandibular alveolar ridge saddle-type defects (2 defects/jaw quadrant) in seven young adult Hound dogs were assigned to receive rhBMP-2/ACS, rhBMP-2/ACS combined with GBR (rhBMP-2/GBR), GBR, and surgery controls. The animals were euthanized at 12 weeks post-surgery when block sections of the defect sites were collected for histologic analysis.


RESULTS
Clinical complications included swelling for sites receiving rhBMP-2 and wound failure with exposure of the barrier device for sites receiving GBR (4/6) or rhBMP-2/GBR (3/7). The radiographic evaluation showed substantial bone fill for sites receiving rhBMP-2/ACS, rhBMP-2/GBR, and GBR. In particular, sites receiving rhBMP-2/GBR presented with seroma-like radiolucencies. The surgery control exhibited moderate bone fill. To evaluate the biologic potential of the specific protocols, sites exhibiting wound failure were excluded from the histometric analysis. Sites receiving rhBMP-2/ACS or rhBMP-2/GBR exhibited bone fill averaging 101%. Bone fill averaged 92% and 60%, respectively, for sites receiving GBR and surgery controls. Bone density ranged from 50% to 57% for sites receiving rhBMP-2/ACS, GBR, or surgery controls. Bone density for sites receiving rhBMP-2/GBR averaged 34% largely due to seroma formation encompassing 13% to 97% of the sites.


CONCLUSIONS
rhBMP-2/ACS appears to be an effective alternative to GBR in the reconstruction of advanced alveolar ridge defects. Combining rhBMP-2/ACS with GBR appears to be of limited value due to the potential for wound failure or persistent seromas.
Jovanovic
Sascha A
SA
Division of Oral Biology & Medicine, UCLA School of Dentistry, Los Angeles, CA, USA. sascha@jovanoviconline.com
Hunt
Dennis R
DR
Bernard
George W
GW
Spiekermann
Hubertus
H
Wozney
John M
JM
Wikesjö
Ulf M E
UM
D016301:Alveolar Bone Loss / Q000601:surgery*; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000473:pathology; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D015519:Bone Density / Q000502:physiology; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000502:physiology; D004285:Dogs; D004337:Drug Carriers; D005781:Gelatin Sponge, Absorbable; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008567:Membranes, Artificial; D010012:Osteogenesis / Q000502:physiology; D011183:Postoperative Complications; D011859:Radiography; D011994:Recombinant Proteins / Q000627:therapeutic use*; D049291:Seroma / Q000000981:diagnostic imaging / Q000209:etiology; D013529:Surgical Wound Dehiscence / Q000209:etiology; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*
D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D004337:Drug Carriers; D008567:Membranes, Artificial; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2