Titanium particles enhanced osteoclast differentiation and osteoclast bone resorption activity in vitro

The aim of this study was to evaluate the effect of titanium particles that detached from dental implants on osteoclast differentiation and their bone resorption activity. Osteoclasts were generated by titanium particles medium and conditioned medium with or without anti-receptor activator of nuclear factor kappa-B ligand (RANKL). The number of osteoclast was counted and the resorption areas on dentin slices were measured. Moreover, the expression of RANKL and the phagocytosis of titanium particles by cells were evaluated by western blot and transmission electron microscopy (TEM), respectively. Osteoclast differentiation and osteoclast bone resorption activity were enhanced both in titanium particles medium and conditioned medium. In addition, titanium particles promote the expression of RANKL in osteoblasts and the phagocytosis of titanium particles by osteoblasts was demonstrated by TEM. In conclusion, titanium particles enhanced osteoclast generation and their activity and could induce bone resorption around dental implants.