The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, 10833 Le Conte Avenue, Los Angeles, CA 90095-1668, USA.
Dent Mater. 2010 Apr;26(4):275-87. doi: 10.1016/j.dental.2009.11.077. Epub 2009 Dec 16.
There is a great demand for dental implant surfaces to accelerate the process of peri-implant bone generation to reduce its healing time and enable early loading. To this end, an inverse correlation between the proliferation and functional maturation (differentiation) in osteoblasts presents a challenge for the rapid generation of greater amounts of bone. For instance, osteoblasts exhibit faster differentiation but slower proliferation on micro-roughened titanium surfaces. Using a unique micro-nano-hierarchical topography of TiO(2) that mimics biomineralized matrices, this study demonstrates that this challenge can be overcome without the use of biological agents.
Titanium disks of grade 2 commercially pure titanium were prepared by machining (smooth surface). To create a microtexture with peaks and valleys (micropit surface), titanium disks were acid-etched. To create 200-nm TiO(2) nanonodules within the micropits (nanonodule-in-micropit surface), TiO(2) was sputter-deposited onto the acid-etched surface. Rat bone marrow-derived osteoblasts and NIH3T3 fibroblasts were cultured on machined smooth, micropit, and nanonodule-in-micropit surfaces.
Despite the substantially increased surface roughness, the addition of 200-nm nanonodules to micropits increased osteoblast proliferation while enhancing their functional differentiation. In contrast, this nanonodule-in-micropit surface decreased proliferation and function in fibroblasts.
The data suggest the establishment of cell-selectively functionalized nano-in-micro smart titanium surfaces that involve a regulatory effect on osteoblast proliferation, abrogating the inhibitory mechanism on the micropitted surface, while enhancing their functional differentiation. Biomimetic and controllable nature of this nanonodules-in-micropits surface may offer a novel micro-to-nanoscale hierarchical platform to biologically optimize nanofeatures of biomaterials. Particularly, this micro-nano-hybrid surface may be an effective approach to improve current dental implant surfaces for accelerated bone integration.
人们对牙科种植体表面有很大的需求，以加速种植体周围骨的生成过程，从而缩短其愈合时间并实现早期负载。为此，成骨细胞的增殖与功能成熟（分化）之间呈负相关，这给大量快速生成骨带来了挑战。例如，在微粗糙钛表面，成骨细胞分化更快，但增殖更慢。本研究利用模仿生物矿化基质的 TiO2 独特的微纳分级形貌，证明了在不使用生物制剂的情况下，可以克服这一挑战。
通过机械加工（光滑表面）制备商用纯钛 2 级钛合金圆盘。为了在钛盘上制造峰谷（微坑表面）微纹理，对钛盘进行酸蚀。为了在微坑内制造 200nm TiO2 纳米结节（微坑内纳米结节表面），将 TiO2 溅射沉积到酸蚀表面。将大鼠骨髓源性成骨细胞和 NIH3T3 成纤维细胞培养在机械加工的光滑表面、微坑表面和纳米结节微坑表面上。
尽管表面粗糙度显著增加，但在微坑中添加 200nm 纳米结节会增加成骨细胞的增殖，同时增强其功能分化。相比之下，纳米结节微坑表面会降低成纤维细胞的增殖和功能。
数据表明，建立了细胞选择性功能化纳米微智能钛表面，该表面对成骨细胞增殖具有调节作用，消除了微坑表面的抑制机制，同时增强了其功能分化。这种纳米结节微坑表面的仿生和可控特性为生物优化生物材料的纳米结构提供了一个新的微纳分级平台。特别是，这种微纳混合表面可能是一种有效的方法，可以改善当前的牙科种植体表面，以加速骨整合。
