Mechanisms involved in osteoblast response to implant surface morphology

Osteoblasts respond to surface topography with altered morphology, prolifer ation, and differentiation. The effects observed vary with cell culture mod el and the topographical features of the surface. In general, increased sur face roughness is associated with decreased proliferation and increased dif ferentiation. Cell responses to hormones, growth factors, and cytokines are altered as well, as is autocrine production of these factors. The cells in teract with the surface via integrin receptors, and their expression is als o surface roughness-dependent. Integrin binding to cell attachment proteins activates signal transduction cascades, including those mediated by protei n kinase C and phospholipase A,. These signaling pathways are also used by regulatory factors, which results in synergistic responses. Prostaglandins are important mediators of the surface effects, and both constitutive and i nducible cyclooxygenase are involved.