Cell populations derived from human embryonic bone were isolated according to the ability of osteoblasts to migrate from bone onto glass fragments. Morphologic and biochemical assays showed (1) osteoblast-like appearance; (2) elevated alkaline phosphatase 1,25(OH)2D3 responsive activity associated with plasma membranes and matrix vesicles; (3) production of a thick extracellular matrix, mainly composed of Type I collagen, which mineralized in the presence of 10 mM beta-glycerophosphate; and (4) higher growth rate and viability when compared with their mature counterpart. Cultures of embryonic cells were challenged with particles of several biomaterials, and their effects on morphology, vitality, and osteogenic capacity of the cultured cells were tested. Stainless steel, titanium alloy, Co-Cr-Mo alloy (vitallium), carbon fiber-reinforced polybutylene terephtalate, ultra-high molecular weight polyethylene, ceramic, calcium phosphate, and hydroxyapatite did not exert any significant deleterious effects on the cultured human osteoblasts.