Niedhart Christopher, Maus Uwe, Redmann Eva, Schmidt-Rohlfing Bernhard, Niethard Fritz U, Siebert Christian H
Department of Orthopedic Surgery, University of Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
J Biomed Mater Res A. 2003 Apr 1;65(1):17-23. doi: 10.1002/jbm.a.10362.
The aim of the study was to determine bone-regenerative effects of an in situ setting tricalcium phosphate (TCP) cement combined with rhBMP-2 and to compare it with autologous bone graft. A trepanation defect of 1.5 mm in the femur diaphysis of Sprague-Dawley rats was filled with an in situ setting TCP cement combined with 0, 0.25, 2.5, or 25 microg of rhBMP-2, an autologous bone graft, or left empty. The rats were euthanized after 1 and 3 weeks and examined by radiography, histology, histomorphometry, and bending tests. All TCP groups with or without BMP-2 showed a good bony ingrowth with a close bone-cement contact. Histomorphometric analysis showed no increase of new bone formation in the defect, but a dose-dependent increase in callus formation with a maximum at 25 microg of rhBMP-2. As shown with intravital fluorochrome staining, new bone formation started earlier using rhBMP-2. Bone strength, measured in a three-point bending test and expressed in percentage of the contralateral healthy femur, was 75% for TCP + 25 microg rhBMP-2, 44% for TCP + 2.5 microg rhBMP-2, and 34% for autologous bone graft. TCP particles were detectable in all groups after 3 weeks. Callus formation and bending strength of the TCP + 25 microg rhBMP-2 group was superior to autologous bone graft. So TCP/rhBMP-2 composites may prove to be an effective substitute for autologous bone grafts.
本研究的目的是确定原位固化磷酸三钙（TCP）骨水泥联合重组人骨形态发生蛋白-2（rhBMP-2）的骨再生效果，并将其与自体骨移植进行比较。用含有0、0.25、2.5或25微克rhBMP-2的原位固化TCP骨水泥、自体骨移植或不做处理填充Sprague-Dawley大鼠股骨干1.5毫米的环锯缺损。1周和3周后对大鼠实施安乐死，并通过X线摄影、组织学、组织形态计量学和弯曲试验进行检查。所有含或不含BMP-2的TCP组均显示出良好的骨长入，骨与骨水泥紧密接触。组织形态计量学分析显示缺损处新骨形成没有增加，但骨痂形成呈剂量依赖性增加，在25微克rhBMP-2时达到最大值。如活体荧光染料染色所示，使用rhBMP-2时新骨形成开始得更早。在三点弯曲试验中测量并以对侧健康股骨百分比表示的骨强度，TCP + 25微克rhBMP-2组为75%，TCP + 2.5微克rhBMP-2组为44%，自体骨移植组为34%。3周后在所有组中均检测到TCP颗粒。TCP + 25微克rhBMP-2组的骨痂形成和弯曲强度优于自体骨移植。因此，TCP/rhBMP-2复合材料可能被证明是自体骨移植的有效替代品。
