백서 두개골결손모델에서 실크단백과 골형성단백 이식체가 골재생에 미치는 영향

• Published in: Journal of the Korean Association of Oral and Maxillofacial Surgeons Vol. 36; no. 5; pp. 366 - 374
• Main Authors: 남정훈(Jeong-Hun Nam), 노경록(Kyung-Lok Noh), 방은오(Eun-O Pang), 유우근(Woo-Geun Yu), 강응선(Eung-Sun Kang), 권해용(Hae-Yong Kweon), 김성곤(Seong-Gon Kim), 박영주(Young-Ju Park)
• Format: Journal Article
• Language: Korean
• Published: 대한구강악안면외과학회 30.10.2010; Korean Association Of Oral And Maxillofacial Surgeons
• Subjects: 치의학; Recombinant human bone morphogenetic protein-2; Silk; Tissue scaffolds; Fibroins; Bone regeneration
• ISSN: 2234-7550; 2234-5930

Introduction: This study evaluated the capability of silk fibroin (SF) and recombinant human bone morphogenetic protein-2 loaded SF (SF-BMP) as a bone defect replacement matrix when grafted in a calvarial bone defect of rats in vivo. Materials and Methods: A total 70 calvarial critical size defects (5.0 mm in diameter) made on 35 adult female Sprague-Dawley rats were used in this study. The defects were transplanted with (1) rhBMP-2 loaded silk fibroin graft (SF-BMP: 0.8+10 μg), (2) Silk fibroin (SF: 10 μg), and (3) no graft material (Raw). The samples were evaluated with soft x-rays, alkaline phosphatase activity, calcium/phosphate quantification, histological and histomorphometric analysis at postoperative 4 and 8 weeks. Results: The SF-BMP group (48.86±14.92%) had a significantly higher mean percentage bone area than the SF group (24.96±11.01%) at postoperative 4 weeks.(P<0.05) In addition, the SF-BMP group (40.01±12.43%) had a higher % bone area at postoperative 8 weeks than the SF group (33.26±5.15%). The mean ratio of gray scale levels to the host bone showed that the SF-BMP group (0.67±0.08) had a higher mean ratio level than the SF group (0.61±0.09) at postoperative 8 weeks. These differences were not statistically significant.(P=0.168 and P=0.243, respectively)The ratio of the calcium and phosphate contents of the SF-BMP (0.93±0.22) group was lower than that of the SF (1.90±1.42) group at postoperative 4 weeks. However, the SF-BMP group (0.75±0.31) had a higher Ca/PO4 ratio than the SF (0.68±0.04) at postoperative 8 weeks. These differences were not statistically significant.(P=0.126 and P=0.627, respectively) For the bone-specific alkaline phosphatase (ALP) activity, which is recognized as a reliable indicator of the osteoblast function, the SF-BMP (23.71±8.60 U/L) groups had a significantly higher value than the SF group (12.65±6.47 U/L) at postoperative 4 weeks.(P<0.05) At postoperative 8 weeks, the SF-BMP (21.65±10.02 U/L) group had a lower bone-specific ALP activity than the SF group (16.72±7.35 U/L). This difference was not statistically significant.(P=0.263) For the histological evaluation, the SF-BMP group revealed less inflammation, lower foreign body reactions and higher bone healing than the SF group at postoperative 4 and 8 weeks. The SF group revealed more foreign body reactions at postoperative 4 weeks. However, this immunogenic reaction decreased and the remnant of grafted material was observed at postoperative 8 weeks. For histomorphometric analysis, the SF-BMP group had a significantly longer bone length to total length ratio than those of the SF group at postoperative 4 and 8 weeks.(P<0.05)Conclusion: The rhBMP-2 loaded silk fibroin graft revealed fewer immunoreactions and inflammation as well as more new bone formation than the pure silk fibroin graft. Therefore, silk fibroin may be a candidate scaffold for tissue engineered bone regeneration. KCI Citation Count: 0