The effect of TiO2 nanotubes layered on surfaces of titanium to be used in implantology on the proliferative and secretory activity of fibroblasts

Nowadays titanium and its alloys are the most widely used metallic materials in medicine. In comparison with other metals, titanium has several advantages including biocompatibility, good mechanic properties and corrosion resistance. This research was focused on the studies of proliferative and secretory characteristics of human fibroblasts, cultured on nanotube-layered titanium surfaces as well as the levels of collagen and non-collagenous proteins deposition. Experiments were performed with 2 fibroblast lines isolated from skin samples of 2 donors. Fibroblasts were grown on titanium disks with untreated and anodized surfaces and on the tissue culture treated plastic. Cells were fixed after 3, 5, 7 and 9 days of cultivation. At each time point six samples were analyzed for each surface type. Cell density was estimated by counting cell nuclei, stained with DAPI. IL-6, IL-8/CXCL8 and pro-collagen I concentrations were measured by ELISA, the quantity of collagen and non-collagenic proteins on surfaces was calculated by measuring the level of absorption of Sirius Red and Fast Green dyes, respectively. The results of experiments indicate that the modification of titanium surface with nanotubes does not trigger the formation of fibrous capsule during osseointegration. However, elevated levels of secreted chemokine IL-8/CXCL8, which attracts neutrophils, were observed on anodized samples thus implying possible increased inflammatory response. To get more insights on the role of nanotubes in osseointegration further research is needed.

titanium implants, anodized surface, nanotubes, fibroblasts, cell proliferation and secretion, collagen