Rapid bone regeneration by Escherichia coli-derived recombinant human bone morphogenetic protein-2 loaded on a hydroxyapatite carrier in the rabbit calvarial defect model.
BACKGROUND
The aim of this study was to determine the osteoconductivity of hydroxyapatite particles (HAP) as a carrier for Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2). Two 8-mm diameter bicortical calvarial defects were created in each of 20 rabbits. One of each pair of defects was randomly assigned to be filled with HAP only (HAP group) or ErhBMP-2 loaded HAP (ErhBMP-2/HAP group), while the other defect was left untreated (control group). The animals were killed after either 2 weeks (n = 10) or 8 weeks (n = 10) of healing, and histological, histomorphometric, and tomographic analyses were performed.


RESULTS
All experimental sites showed uneventful healing during the postoperative healing period. In both histomorphometric and tomographic analyses, the new bone area or volume of the ErhBMP-2/HAP group was significantly greater than that of the HAP and control groups at 2 weeks (p < 0.05). However, at 8 weeks, no significant difference in new bone area or volume was observed between the ErhBMP-2/HAP and HAP groups. The total augmented area or volume was not significantly different between the ErhBMP-2/HAP and HAP groups at 2 and 8 weeks.


CONCLUSIONS
Combining ErhBMP-2 with HAP could significantly promote rapid initial new bone formation. Moreover, HAP graft could increase new bone formation and space maintenance, therefore it might be one of the effective carriers of ErhBMP-2.
Department of Periodontology, College of Dentistry, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul, 120-752 Republic of Korea.
Chung-Hoon
CH
Chung
Department of Periodontology, College of Dentistry, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul, 120-752 Republic of Korea.
You-Kyoung
YK
Kim
Department of Periodontology, College of Dentistry, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul, 120-752 Republic of Korea.
Jung-Seok
JS
Lee
Department of Periodontology, College of Dentistry, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul, 120-752 Republic of Korea.
Ui-Won
UW
Jung
Department of Periodontology, School of Medicine, Ewha Womans University, Seoul, Republic of Korea.
Eun-Kyoung
EK
Pang
Department of Periodontology, College of Dentistry, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul, 120-752 Republic of Korea.
Seong-Ho
SH
Choi
Bone regeneration; Calvarial intraosseous defect model; Escherichia coli-derived recombinant human bone; Hydroxyapatite; Morphogenetic protein-2; Tissue engineering