Human gingival fibroblast functions are stimulated by oxidized nano-structured titanium surfaces

Objectives: The aim of this study was to analyze the features of an oxidized titanium implant surface and to evaluate its effects on the response of human gingival fibroblasts. Methods: 10 mm x 10 mm x 1 mm turned (control) and oxidized (test) titanium samples (P.H.I. s.r.l., Italy) were examined by scanning electron microscopy and atomic force microscopy and characterized by height, spatial and hybrid roughness parameters. Primary cultures of human gingival fibroblasts were seeded on titanium samples, and cell morphology, adhesion, proliferation and extracellular matrix deposition, in terms of type I collagen synthesis, were evaluated. Results: Control and test surfaces appeared considerably different at the microscopic analyses: 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 rate, as well as collagen synthesis, were greater on oxidized vs turned surfaces. Conclusions: 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 and, mostly, hybrid parameters. Furthermore, oxidized surfaces enhanced human gingival fibroblast adhesion, proliferation and extracellular matrix deposition, and this could be due to the different structure at micro-and nano-scale levels. (C) 2013 Elsevier Ltd. All rights reserved.