A Review of Biomimetic Topographies and Their Role in Promoting Bone Formation and Osseointegration: Implications for Clinical Use

Abstract

The use of metallic and polymeric materials for implants has been increasing over the past decade. This trend can be attributed to a variety of factors including a significant increase in basic science research focused on implant material characteristics and how various surface modifications may stimulate osseointegration and, ultimately, fusion. There are many interbody fusion devices and dental implants commercially available; however, detailed information about their surface properties, and the effects that various materials and surface modifications may have on osteogenesis, is lacking in the literature. While the concept of bone-implant osseointegration is a relatively recent addition to the spine fusion literature, there is a comparatively large body of literature related to dental implants. The purpose of this article is to summarize the science of surface modified bone-facing implants, focusing on biomimetic material chemistry and topography of titanium implants, to promote a better understanding of how these characteristics may impact bone formation and osseointegration. This manuscript has the following aspects: highlights the role of titanium and its alloys as potent osteoconductive bioactive materials; explores the importance of biomimetic surface topography at the macro-, micro- and nano-scale; summarizes how material surface design can influence osteogenesis and immune responses in vitro; focuses on the kinds of surface modifications that play a role in the process. Biomimetic surface modifications can be varied across many clinically available biomaterials, and the literature supports the hypothesis that those biomaterial surfaces that exhibit physical properties of bone resorption pits, such as roughness and complex hierarchical structures at the submicron and nanoscale, are more effective in supporting osteoblast differentiation in vitro and osteogenesis in vivo.

In Vitro and In Vivo Studies of Hydrogenated Titanium Dioxide Nanotubes with Superhydrophilic Surfaces during Early Osseointegration

“…New bone formation proceeds in a structural osteoclast resorption pit preconditioned by osteoclast-mediated bone resorption, leading to features in micro-, meso-, and nanoscale dimensions [ 39 ]. Therefore, biomimetic topography has been investigated to improve osseointegration [ 2 ]. Among these, nanotopography is a critical factor in surface modification.…”

“…However, unsatisfactory osseointegration after implantation has become a major issue due to the biological inertness of titanium [ 1 ]. Extensive investigation revealed that surface modification of titanium implants may induce rapid and reliable osseointegration [ 2 , 3 ]. Xu et al [ 4 ] used electrochemical etching and anodic oxidation to prepare surfaces with ordered microholes (20 µm in diameter) and titanium dioxide nanotubes (TNTs, 70 nm in diameter), and the bio-inspired micro/nanotextured surface improved osseointegration.…”

Evaluation of the Biocompatibility and Osteogenic Properties of Metal Oxide Coatings Applied by Magnetron Sputtering as Potential Biofunctional Surface Modifications for Orthopedic Implants

“…Surface roughness in the micro range (1–100 µm; substrate roughness) modifies cell proliferation and viability, and osseointegration [ 58 , 72 , 73 , 74 ]. Nevertheless, surface nano roughness also modifies the cell response by controlling the protein layer adsorbed on the material surface and, consequently, the extracellular matrix composition [ 58 , 75 , 76 , 77 ].…”

Analysis of disordered abrasive scratches on titanium surfaces and their impact on nuclear translocation of yes-associated protein

“…The bone-titanium contact rate is approximately 30-70% 5-7 , posing risks of implant loosening and bacterial infections 8 . To improve the implant-to-cell contact, the behavior of cells on implant devices should be analyzed to increase the success rate of implantations and treatments that use Ti-based medical devices.Surface morphology is a critical parameter affecting cell behavior, such as adhesion, proliferation, and differentiation 8,9 . Therefore, optimization of implant surface morphology can improve the implant-to-cell contact 10 .…”

“…Surface morphology is a critical parameter affecting cell behavior, such as adhesion, proliferation, and differentiation 8,9 . Therefore, optimization of implant surface morphology can improve the implant-to-cell contact 10 .…”