In this study the influence of physically different titanium implant surfaces (smooth, rough-textured, porous-coated) on osseointegration was examined. Embryonic chick calvarial osteoblasts were cultured on the various titanium disks in vitro. Synthesis of extracellular matrix and mineralization were evaluated. Osteoblasts cultured on rough-textured and porous-coated titanium disks exhibited substantially higher rates of bone-specific extracellular matrix synthesis (collagen) and subsequent mineralization than the osteoblasts on smooth titanium disks or plastic tissue culture dishes as controls. From this it can be concluded that porous or rough titanium implant surfaces may act like "natural" substrates permiting microscopic tissue/cell ingrowth and thus improving clinical implant fixation.