Vehof Johan W M, Haus Marcus T U, de Ruijter Anja E, Spauwen Paul H M, Jansen John A
Department of Biomaterials, College of Dental Science, University Medical Center Nijmegen, The Netherlands.
Clin Oral Implants Res. 2002 Feb;13(1):94-102. doi: 10.1034/j.1600-0501.2002.130112.x.
The osteoconductive properties of porous titanium (Ti) fiber mesh with or without a calcium phosphate (Ca-P) coating and osteoinductive properties of noncoated Ti fiber mesh loaded with recombinant human Transforming Growth Factor beta-1 (rhTGF-beta1) were investigated in a rabbit non-critical size cranial defect model. Nine Ca-P-coated and 18 non-coated porous titanium implants, half of them loaded with rhTGF-beta1, were bilaterally placed in the cranium of 18 New Zealand White rabbits. At 8 weeks postoperative, the rabbits were sacrificed and the skulls with the implants were retrieved. Histological analysis demonstrated that in the TGF-beta1-loaded implants, bone had been formed throughout the implant, up to its center, whereas in the non-loaded implants only partial ingrowth of bone was observed. Bone formation had a trabecular appearance together with bone marrow-like tissue. No difference in ingrowth could be observed between the non-TGF-beta1-loaded non-coated implants and the Ca-P-coated ones. All histological findings were confirmed by image analysis: 97% ingrowth was seen in the rhTGF-beta1-loaded implants, while only 57% and 54% ingrowth was observed in the non-loaded Ca-P-coated and non-coated implants, respectively. Bone surface area and bone fill were significantly higher in the rhTGF-beta1-loaded implants (1.37 mm2 and 36%, respectively) than in the non-loaded implants (0.57 mm2 and 26%). No statistical difference was found for any parameter between the Ca-P-coated and noncoated implants. Quadruple fluorochrome labeling showed that in the Ti and Ti-CaP implants mainly bone guidance had occurred from the former defect edge, while in the Ti-TGF-beta1 implants bone formation had mainly started in the center of a pore and proceeded in a centrifugal manner. Our results show that: (1) the combination of Timesh with TGF-beta1 can induce orthotopic bone formation; (2) Ti-fiber mesh has good osteoconductive properties; (3) a thin Ca-P coating, as applied in this study, does not seem to further enhance the bone-conducting properties of a titanium scaffold material.
在兔非临界尺寸颅骨缺损模型中，研究了有或无磷酸钙（Ca-P）涂层的多孔钛（Ti）纤维网的骨传导特性，以及负载重组人转化生长因子β-1（rhTGF-β1）的未涂层Ti纤维网的骨诱导特性。将9个Ca-P涂层和18个未涂层的多孔钛植入物（其中一半负载rhTGF-β1）双侧植入18只新西兰白兔的颅骨中。术后8周，处死兔子并取出带有植入物的颅骨。组织学分析表明，在负载TGF-β1的植入物中，整个植入物直至其中心都形成了骨，而在未负载的植入物中仅观察到部分骨向内生长。骨形成具有小梁外观并伴有骨髓样组织。在未负载TGF-β1的未涂层植入物和Ca-P涂层植入物之间未观察到向内生长的差异。所有组织学结果均通过图像分析得到证实：在负载rhTGF-β1的植入物中观察到97%的向内生长，而在未负载的Ca-P涂层和未涂层植入物中分别仅观察到57%和54%的向内生长。负载rhTGF-β1的植入物的骨表面积和骨填充率（分别为1.37平方毫米和36%）显著高于未负载的植入物（0.57平方毫米和26%）。在Ca-P涂层和未涂层植入物之间的任何参数均未发现统计学差异。四重荧光染料标记显示，在Ti和Ti-CaP植入物中，主要是从先前的缺损边缘发生骨引导，而在Ti-TGF-β1植入物中，骨形成主要始于孔隙中心并以离心方式进行。我们的结果表明：（1）Ti与TGF-β1的组合可诱导原位骨形成；（2）Ti纤维网具有良好的骨传导特性；（3）本研究中应用的薄Ca-P涂层似乎并未进一步增强钛支架材料的骨传导特性。
