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Updated: Jun 17, 2026

Distinctive Capillary Action by Micro-channels in Bone-like Templates can Enhance Recruitment of Cells for Restoration of Large Bony Defect
Published on: September 11, 2015
Selective cell affinity of biomimetic micro-nano-hybrid structured TiO2 overcomes the biological dilemma of
Norio Hori1, Fuminori Iwasa, Takeshi Ueno
1The 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.
Objective:
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.
Methods:
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.
Results:
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.
Significance:
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.

