Osteoblast response to alumina and titania nanometer wear debris

Osteoblast (bone-forming cells) response to different sizes of alumina and titania wear debris particles were investigated in the present in vitro study. Such wear debris may result from friction between articulating components of orthopedic implants composed of nanophase ceramics. Results provided the first evidence of increased osteoblast proliferation in the presence of nanometer compared to conventional-dimension (i.e., micrometer) ceramic particles. The present study also indicated a different early response (through altered mRNA expression and protein synthesis) of osteoblasts exposed to nanometer as apposed to micrometer particle size ceramics. Evidence of a less detrimental effect of nanometer compared to conventional-dimension wear debris on osteoblast function offers additional evidence that nanophase ceramics may become the next generation of bone prosthetic materials with improved osseointegrative (that is, ability to bond to juxtaposed bone in situ) properties.