Human gingival fibroblast functions are stimulated by oxidized titanium surfaces

Titanium implant surface topography may exert significant effects on peri-implant soft tissue integration. The aim of this study was to analyze the features of a novel oxidized titanium implant surface and to evaluate its effect on the response of human gingival fibroblasts (HGF).10x10x1 mm turned (control) and oxidized (test) titanium samples (P.H.I. s.r.l., San Vittore Olona, Milano, Italy) were examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM) and characterized by height, spatial and hybrid roughness parameters. Primary cultures of HGF were seeded on titanium samples and cell morphology, adhesion, proliferation and extracellular matrix deposition, in terms of type I gollagen synthesis, were evaluated. At SEM and AFM analyses, control and test surfaces appeared considerably different: turned samples were grooved, whereas oxidized surfaces showed a more complex micro- and nano-scaled texture, as evidenced by roughness parameters. Cell adhesion and proliferation parameters, as well as collagen synthesis were greater on oxidized (p<0.05 at least) vs turned surfaces.Although both control and test samples were in the range of average roughness proper of smooth surfaces, they exhibited significantly different topographic properties in terms of height, spatial and, mostly, of hybrid parameters. Furthermore, oxidized surfaces enhanced HGF adhesion, proliferation and extracellular matrix deposition, and this could be due to the different structure at micro and nano-scale levels.