Aligned keratin submicrometric-fibers for fibroblasts guidance onto nanogrooved titanium surfaces for transmucosal implants

Biomaterials surface modification represents a very attractive tool to modulate host tissue response. Surface modifications of titanium for bone contact applications have been widely investigated, while only few papers can be found regarding modifications aimed at soft tissue contact. However, soft tissue healing represents a crucial step for percutaneous/transmucosal titanium implants success. Fibroblasts, the soft tissues most representative cells, are known to be sensitive to surface topography. Anyhow, fibroblasts adhesion and spread can be more influenced by the presence of attractive macromolecules; so, within a grooved and keratin-coated Ti surface, cells will align following the strongest biochemical guide provided by keratin submicrometric-fibers. In order to obtain the most effective cell stimulation/guidance keratin submicrometric-fibers should be aligned to substrate nanogrooves. Despite the very promising cells guidance provided by keratin submicrometric-fibers, the strong limitation to their synthesis is related to the macromolecules high sensitivity to environmental parameters (temperature/humidity/pH) which can seriously compromise the feasibility and reproducibility of the final submicrometric-fibers layer. Accordingly, this work has the aim to obtain, for the first time, a coating of submicrometric keratin fibers aligned to the nanogrooves of a Ti substrate, in order to validate the attitude of the coated surface to impart additive topographical plus biochemical signals in the same direction for the stimulation of fibroblasts repopulation.