Purpose: This article reviews the topographic and chemical properties of different oral implant surfaces and in vivo responses to them. Materials and Methods: The article considers detailed mechanical, topographic, and physical characteristics of implant surfaces. Anchorage mechanisms such as biomechanical and biochemical bonding are examined. Osteoattraction and doped surfaces are discussed. Results: Surface quality of an oral implant may be subdivided into mechanical, topographic, and physicochemical properties. Topographic properties are evaluated at the micrometer level of resolution. Moderately rough surfaces (S_a between 1.0 and 2.0 µm) show stronger bone responses than smoother or rougher surfaces. The majority of currently marketed implants are moderately rough. Oral implants permit bone ingrowth into minor surface irregularities-biomechanical bonding or osseointegration. Additional biochemical bonding seems possible with certain surfaces. Osteoattraction is a commercial term without precise biologic correspondence. Surfaces doped with biochemical agents such as bone growth factors have been developed. Conclusion: Moderately roughened surfaces seem to have some clinical advantages over smoother or rougher surfaces, but the differences are small and often not statistically significant. Bioactive implants may offer some promise.