Micro-/nano-topography of selective laser melting titanium enhances adhesion and proliferation and regulates adhesion-related gene expressions of human gingival fibroblasts and human gingival epithelial cells

Abstract

BackgroundSelective laser melting (SLM) titanium is an ideal option to manufacture customized implants with suitable surface modification to improve its bioactivity. The peri-implant soft tissues form a protective tissue barrier for the underlying osseointegration. Therefore, original microrough SLM surfaces should be treated for favorable attachment of surrounding soft tissues.Material and methodsIn this study, anodic oxidation (AO) was applied on the microrough SLM titanium substrate to form TiO2 nanotube arrays. After that, calcium phosphate (CaP) nanoparticles were embedded into the nanotubes or the interval of nanotubes by electrochemical deposition (AOC). These two samples were compared to untreated (SLM) samples and accepted mechanically polished (MP) SLM titanium samples. Scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction, surface roughness, and water contact angle measurements were used for surface characterization. The primary human gingival epithelial cells (HGECs) and human gingival fibroblasts (HGFs) were cultured for cell assays to determine adhesion, proliferation, and adhesion-related gene expressions.ResultsFor HGECs, AOC samples showed significantly higher adhesion, proliferation, and adhesion-related gene expressions than AO and SLM samples (P<0.05) and similar exceptional ability in above aspects to MP samples. At the same time, AOC samples showed the highest adhesion, proliferation, and adhesion-related gene expressions for HGFs (P<0.05).ConclusionBy comparison between each sample, we could confirm that both anodic oxidation and CaP nanoparticles had improved bioactivity, and their combined utilization may likely be superior to mechanical polishing, which is most commonly used and widely accepted. Our results indicated that creating appropriate micro-/nano-topographies can be an effective method to affect cell behavior and increase the stability of the peri-implant mucosal barrier on SLM titanium surfaces, which contributes to its application in dental and other biomedical implants.

Enhanced Biocompatibility and Antibacterial Activity of Selective Laser Melting Titanium with Zinc-Doped Micro-Nano Topography

“…Specimen Preparation and Treatment. The SLM specimens were manufactured as described previously [12,15]. Briefly, round-disk samples (diameter, 10 mm; thickness, 1 mm) were designed by SolidWorks® 12.0 (SolidWorks Corp, USA).…”

“…After SLM modifications both in vivo and in vitro (i.e., anodic oxidation, alkali-heat treatment, etc. ), remarkable antibacterial properties, bone regeneration, and soft tissue adhesion were demonstrated with an SLM surface [12,14,15]. However, few of them possess both biocompatibility and antibacterial activity at the same time.…”

Structural and biological evaluation of new chitosan membrane for dural closure

“…Chitin particle uniform distributed over the membrane surface and did not make any is flat with minimal roughness. Some researchers have shown that rough surface has greater potential for cell adhesion that is principal for biocompatibility [22]. Just after material interacts with body fluids, protein absorbs onto the surface and plays a role of vesical substrate for cell adhesion.…”

Implant Soft-Tissue Attachment Using 3D Oral Mucosal Models—A Pilot Study

“…The authors demonstrated that cell adhesion was significantly higher on machined and Ti-Unite surfaces than on the SLA implant surfaces. In another study using monolayer primary gingival fibroblasts and keratinocytes, Xu et al [ 47 ] reported that applying anodic oxidation on a micro-roughened, selective laser melted titanium surfaces, and subsequent calcium phosphate nanoparticle embedding resulted in enhanced bioactivity when compared to mechanical polishing. Perez-Diaz et al [ 48 ] demonstrated that the surface morphology of titanium can influence fibroblast cell adhesion and viability differentially and independently of the roughness parameters.…”