Adherence of human oral keratinocytes and gingival fibroblasts to nano-structured titanium surfaces

Abstract

BackgroundA key element for long-term success of dental implants is integration of the implant surface with the surrounding host tissues. Modification of titanium implant surfaces can enhance osteoblast activity but their effects on soft-tissue cells are unclear. Adherence of human keratinocytes and gingival fibroblasts to control commercially pure titanium (CpTi) and two surfaces prepared by anodic oxidation was therefore investigated. Since implant abutments are exposed to a bacteria-rich environment in vivo, the effect of oral bacteria on keratinocyte adhesion was also evaluated.MethodsThe surfaces were characterized using scanning electron microscopy (SEM). The number of adhered cells and binding strength, as well as vitality of fibroblasts and keratinocytes were evaluated using confocal scanning laser microscopy after staining with Live/Dead Baclight. To evaluate the effect of bacteria on adherence and vitality, keratinocytes were co-cultured with a four-species streptococcal consortium.ResultsSEM analysis showed the two anodically oxidized surfaces to be nano-structured with differing degrees of pore-density. Over 24 hours, both fibroblasts and keratinocytes adhered well to the nano-structured surfaces, although to a somewhat lesser degree than to CpTi (range 42-89% of the levels on CpTi). The strength of keratinocyte adhesion was greater than that of the fibroblasts but no differences in adhesion strength could be observed between the two nano-structured surfaces and the CpTi. The consortium of commensal streptococci markedly reduced keratinocyte adherence on all the surfaces as well as compromising membrane integrity of the adhered cells.ConclusionBoth the vitality and level of adherence of soft-tissue cells to the nano-structured surfaces was similar to that on CpTi. Co-culture with streptococci reduced the number of keratinocytes on all the surfaces to approximately the same level and caused cell damage, suggesting that commensal bacteria could affect adherence of soft-tissue cells to abutment surfaces in vivo.

The response of human osteoblasts, epithelial cells, fibroblasts, macrophages and oral bacteria to nanostructured titanium surfaces: a systematic study

“…5,34 Nanoscale topography is currently regarded as a promising approach to surface design; however, the effects of nanotopography have rarely been systematically evaluated. In this study, a Nano surface with homogeneous nanofiber texture was prepared by alkali-hydrothermal treatment, and its effects on tissue healing and antimicrobial property were evaluated in vitro and compared to Smooth surface by polishing and Micro surface by SLA.…”

“…3,4 Moreover, implant surfaces are exposed to a bacteria-rich environment and rapidly become colonized by oral bacteria that can compete with epithelial and connective tissues and cells for binding to the implant surface. 5 Bacterial accumulation may result in infection, destruction of the tissueimplant integration or even implant failure; accordingly, inhibiting bacterial adhesion would be conducive to the success and survival of implants.…”

The Effect of Titanium Surface Modifications on Dental Implant Osseointegration

“…10 ). Furthermore, although beyond the scope of the present chapter, nanometre features of implant surfaces have shown to play a central role not only for osseointegration, but also in terms of peri-implant soft tissue attachment [42,43] , thus enhancing and strengthening the mucosal barrier against oral pathogens.…”

Immunohistochemical Evaluation of Peri-Implant Soft Tissues around Machined and Direct Metal Laser Sintered (DMLS) Healing Abutments in Humans

“…A rough surface can positively influence the attachment of cells [15,16,17]. The cell binding on the surface is mediated by the formation of hemidesmosomes, as in tooth [12,13,15,16,17,18].…”