Abstract: Objective: To evaluate the influence of TiO2 nanotubes with different diameters on periodontal ligament stem cells (PDLSCs) biological changes. Methods: TiO2 nanotubes with different diameters were prepared by means of anodic oxidation at 5, 10 and 20?V voltage on the smooth titanium surface. The samples were divided into smooth titanium group (Ti), 5 V nanotube group (NT5), 10 V nanotube group (NT10) and 20 V nanotube group (NT20). The PDLSCs were obtained using the limiting-dilution technique, and then cultured on different diameters TiO2 nanotubes. The morphology of PDLSCs was observed by using FE-SEM. The cells adhesion was observed by Hoechst staining. The cells’ ALP activity was detected by ALP kit. Sirius red staining and Alizarin red staining were used to observe the collagen secretion and the sample surface extracellular matrix mineralization, respectively. Real time quantitative PCR was employed to detect the cells’ osteogenic and periodontal related genetic level. Results: The ALP staining experiment showed stronger activity in NT5 and NT20 groups than that in Ti group. A large number of mineralized nodules were formed on the surfaces of NT10 groups. TiO2 nanotubes morphology promoted the up-regulation of ALP, FN (NT5 and NT5 at 14 d) and RUNX2 (at 7 d) expression. Conclusions: Different diameters TiO2 nanotube morphology induced the PDLSCs to form different cell cytoskeletons and promoted the early adhesion, collagen secretion and related genes expression of PDLSCs.

Key words: nanotube morphology, TiO2, periodontal ligament stem cell, cell adhesion, osteogenesis mineralization