Laboratory of Bone and Implant Sciences, The Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA.
Biomaterials. 2011 Oct;32(30):7297-308. doi: 10.1016/j.biomaterials.2011.06.033. Epub 2011 Jul 13.
This study introduces nanopolymorphic features of alkali- and heat-treated titanium surfaces, comprising of tuft-like, plate-like, and nodular structures that are smaller than 100 nm and determines whether and how the addition of these nanofeatures to a microroughened titanium surface affects bone-implant integration. A comprehensive assessment of biomechanical, interfacial, and histological analyses in a rat model was performed for machined surfaces without microroughness, sandblasted-microroughened surfaces, and micro-nano hybrid surfaces created by sandblasting and alkali and heat treatment. The microroughened surface accelerated the establishment of implant biomechanical fixation at the early healing stage compared with the non-microroughened surface but did not increase the implant fixation at the late healing stage. The addition of the nanopolymorphic features to the microroughened surface further increased implant fixation throughout the healing time. The area of the new bone within 50 μm proximity of the implant surfaces, which was increased 2-3-fold using microroughened surfaces, was further increased 2-fold using nanopolymorphic surfaces. In contrast, the bone area in a 50-200 μm zone was not influenced by either microroughened or nanopolymorphic surfaces. The percentage of bone-implant contact, which was increased 4-5-fold, using microroughened surfaces, was further increased substantially by over 2-fold throughout the healing period. The percentage of soft tissue intervention between bone and implant surfaces, which was reduced to half by microroughened surfaces, was additionally reduced by the nanopolymorphic surfaces to between one-third and one-fourth, resulting in only 5-7% soft tissue intervention compared with 60-75% for the non-microroughened surface. Thus, using an exemplary alkali- and heat-treated nanopolymorphic surface, this study identified critical parameters necessary to describe the process and consequences of bone-implant integration, for which nanofeatures have specific and substantial roles beyond those of microfeatures. Nanofeature-enhanced osteoconductivity, which resulted in both the acceleration and elevation of bone-implant integration, has clearly been demonstrated.
本研究介绍了经碱热处理后的钛表面的纳米多晶特征，包括小于 100nm 的绒状、板状和结节状结构，并确定了这些纳米特征是否以及如何影响微粗糙钛表面上的骨-植入物整合。通过对无微粗糙表面、喷砂微粗糙表面和通过喷砂和碱热处理制成的微-纳混合表面的大鼠模型进行生物力学、界面和组织学分析的综合评估，研究了机械加工表面、喷砂微粗糙表面和微-纳混合表面。与非微粗糙表面相比，微粗糙表面在早期愈合阶段加速了植入物生物力学固定的建立，但在晚期愈合阶段并未增加植入物固定。在微粗糙表面的基础上添加纳米多晶特征进一步增加了整个愈合时间内的植入物固定。在距植入物表面 50μm 范围内的新骨面积增加了 2-3 倍，使用微粗糙表面进一步增加了 2 倍。相比之下，50-200μm 范围内的骨面积不受微粗糙或纳米多晶表面的影响。骨-植入物接触百分比增加了 4-5 倍，使用微粗糙表面进一步增加了 2 倍以上，整个愈合期间增加了 2 倍以上。骨与植入物表面之间的软组织干预百分比降低了一半，微粗糙表面进一步降低了一半以上，纳米多晶表面将其降低至三分之一到四分之一之间，与非微粗糙表面的 60-75%相比，软组织干预仅为 5-7%。因此，使用示例性的碱和热处理纳米多晶表面，本研究确定了描述骨-植入物整合过程和结果所需的关键参数，其中纳米特征除了微特征之外，还具有特定且重要的作用。已经清楚地证明了纳米特征增强的骨传导性，这导致了骨-植入物整合的加速和提高。
