Commercially pure Ti and Ti-6Al-4V have been widely used as dental implant materials. Several reports have demonstrated that there are subtle differences in the nature of the oxide between these two materials which may have important biological consequences. An earlier report by our group demonstrated differences in oxide chemistry between cpTi and Ti alloy does not affect short term in vitro responses of osteoblast cultures. In this work, long term phenotypic expression of typical bone cell markers such as osteocalcin and alkaline phosphatase were not different between metal or control surfaces. There was a slight difference in total Ca+2 per culture for alloy compared to cpTi, however, these differences were not statistically different. Based on this work, both cpTi and Ti alloy surfaces support in vitro biological mineralization and are in general agreement with in vivo findings.