Influence of etched microgrooves of uniform dimension on in vitro responses of human gingival fibroblasts

Objective: The purpose of this study was to investigate the influence of titanium (Ti) substrata with etched surface microgrooves on in vitro responses of human gingival fibroblasts. Material and methods: Commercially pure Ti discs with surface microgrooves 15, 30, and 60 mm in width were fabricated using photolithography. Microgrooves 15 mm in widths were designed to be 3.5 mu m in depth, whereas microgrooves 30 and 60 mm in width varied between 5 and 10 mu m in depth. The entire surface of the microgrooved Ti substrata was further acid etched and used as the five experimental groups in this study (E15/3.5, E30/5, E30/10, E60/5, and E60/10), whereas the smooth and acid-etched Ti discs were both used as the control (NE0 and E0). Human gingival fibroblasts were cultured on all groups of substrata on successive timelines. Fibroblast adhesion and morphology was analyzed using confocal laser scanning microscopy (CLSM). Cell adhesion and proliferation were analyzed and compared using crystal violet staining and sulforhodamine B protein staining assays, respectively. Results: In CLSM, the cells in E30/10 and E60/10 were observed to be able to readily descend into and form focal adhesions inside the microgrooves, whereas the cells in E15/3.5 were mostly found on the ridge tops. Cell adhesion was significantly increased in E60/10 compared with that in NE0 or E0 at 4-h incubation. Cell proliferation was significantly increased in E60/10 and E15/3.5 compared with NE0 or E0 after 72 and 96 h of culture. Conclusion: This study indicates that Ti substrata with etched microgrooves 60 mm in width and 10 mm in depth significantly enhance human gingival fibroblast adhesion and proliferation.