Mustafa K, Wennerberg A, Wroblewski J, Hultenby K, Lopez B S, Arvidson K
Department of Basic Oral Sciences, Faculty of Odontology, Karolinska Institute, Huddinge, Sweden.
Clin Oral Implants Res. 2001 Oct;12(5):515-25. doi: 10.1034/j.1600-0501.2001.120513.x.
In the complex process of bone formation at the implant-tissue interface, implant surface roughness is an important factor modulating osteoblastic function. In this study, primary cultures of osteoblast-like cells, derived from human mandibular bone, were used. The aim was to examine the effect of varying surface roughness of titanium implant material on cellular attachment, proliferation and differentiation. A recognized method of increasing surface roughness and enlarging the surface area of titanium implants is by blasting with titanium dioxide particles: the four specimen types in the study comprised surfaces which were machine-turned only, or blasted after turning, with 63-90 microm, 106-180 microm, or 180-300 microm TiO(2) particles, respectively. The specimens were analyzed by scanning electron microscopy and confocal laser scanning. The turned samples had the smoothest surfaces: average height deviation (S(a)) of 0.20 microm. The roughest were those blasted with 180-300 microm particles, S(a) value 1.38 microm. Blasting with intermediate particle sizes yielded S(a) values of 0.72 microm and 1.30 microm, respectively. Cell profile areas were measured using a semiautomatic interactive image analyzer. Figures were expressed as percentage of attachment. DNA synthesis was estimated by measuring the amount of [(3)H]-thymidine incorporation into trichloroacetic acid (TCA) insoluble cell precipitates. The specific activity of alkaline phosphatase was assayed using p-nitrophenylphosphate as a substrate. The ability of the cells to synthesize osteocalcin was investigated in serum-free culture medium using the ELSA-OST-NAT immunoradiometric kit. After 3 h of culture, the percentage of cellular attachment did not differ significantly between specimens blasted with 180-300 micromparticles and the turned specimens. All blasted surfaces showed significantly higher [(3)H]-thymidine incorporation than the turned surfaces (P<0.05), with the highest on the surfaces blasted with 180-300 microm particles. Osteocalcin synthesis by the cells in response to stimulation by 1,25(OH)2D3, was also significantly greater (P<0.05) on the surfaces blasted with TiO(2) particles. However, analysis of alkaline phosphatase activity disclosed no significant differences among the four surface modifications. It is concluded that in this cellular model, the proliferation and differentiation of cells derived from human mandibular bone is enhanced by surface roughness of the titanium implant. However, increasing the size of the blasting particles to 300 microm does not further increase the initial attachment of the cells compared to turned surfaces and those blasted with 63-90 microm particles.
在种植体与组织界面的复杂骨形成过程中，种植体表面粗糙度是调节成骨细胞功能的一个重要因素。在本研究中，使用了源自人类下颌骨的成骨样细胞原代培养物。目的是研究钛种植体材料不同表面粗糙度对细胞附着、增殖和分化的影响。一种公认的增加钛种植体表面粗糙度和扩大表面积的方法是用二氧化钛颗粒喷砂处理：本研究中的四种样本类型包括仅经过机械车削的表面，或车削后分别用63 - 90微米、106 - 180微米或180 - 300微米的TiO₂颗粒喷砂处理的表面。通过扫描电子显微镜和共聚焦激光扫描对样本进行分析。车削后的样本表面最光滑：平均高度偏差（S(a)）为0.20微米。最粗糙的是用180 - 300微米颗粒喷砂处理的样本，S(a)值为1.38微米。用中等粒径颗粒喷砂处理得到的S(a)值分别为0.72微米和1.30微米。使用半自动交互式图像分析仪测量细胞轮廓面积。数据以附着百分比表示。通过测量掺入三氯乙酸（TCA）不溶性细胞沉淀物中的[(³)H] - 胸腺嘧啶核苷的量来估计DNA合成。以对硝基苯磷酸为底物测定碱性磷酸酶的比活性。使用ELSA - OST - NAT免疫放射分析试剂盒在无血清培养基中研究细胞合成骨钙素的能力。培养3小时后，用180 - 300微米颗粒喷砂处理的样本与车削样本之间的细胞附着百分比没有显著差异。所有喷砂处理的表面显示出比车削表面显著更高的[(³)H] - 胸腺嘧啶核苷掺入量（P<0.05），其中用180 - 300微米颗粒喷砂处理的表面掺入量最高。在经TiO₂颗粒喷砂处理的表面上，细胞对1,25(OH)₂D₃刺激的反应所合成的骨钙素也显著更多（P<0.05）。然而，碱性磷酸酶活性分析显示四种表面处理之间没有显著差异。得出的结论是，在这个细胞模型中，钛种植体的表面粗糙度增强了源自人类下颌骨的细胞的增殖和分化。然而，与车削表面和用63 - 90微米颗粒喷砂处理的表面相比，将喷砂颗粒尺寸增加到300微米并没有进一步增加细胞的初始附着。
