Much work is needed in the design of more effective bone tissue engineering materials to induce the growth of normal bone tissue. Nanotechnology offers exciting alternatives to traditional bone implants since bone itself is a nanostructured material composed of nanofibered hydroxyapatite well-dispersed in a mostly collagen matrix. For this purpose, poly-lactic-co-glycolic acid (PLGA) was dissolved in chloroform and nanometer grain size titania was dispersed by various sonication powers from 0 W to 166 W. Previous results demonstrated that the dispersion of titania in PLGA was enhanced by increasing the intensity of sonication and that greater osteoblast (bone-forming cells) adhesion correlated with improved nanophase titania dispersion in PLGA. However, adhesion of osteoblasts to material surfaces, alone, is not adequate to determine long-term functions of implant materials. For this reason, and as a next step to determine the efficacy of nanocomposites in bone applications, subsequent functions of osteoblasts on nanophase titania/PLGA composites were investigated in vitro in this study. For the first time, results correlated better osteoblast long-term functions, specifically the deposition of calcium-containing mineral, with improved nanophase titania dispersions in PLGA.In this manner, the present study demonstrated that PLGA composites with well-dispersed nanophase titania can improve osteoblast functions necessary for the further investigation of these materials in orthopedic applications.