Macrophages play an important role at the implant-tissue interface. Their activity is extremely complex but above all they are phagocytic cells. Phagocytosis is accompanied by a sequence of biochemical reactions known as "the oxidative burst" (BO). The fundamental physiological significance of this phenomenon is to provide the phagocytes with an efficient microbicidal mechanism. Our aim was to prepare an objective method for screening biomaterials that could influence macrophagic defence mechanisms against a possible implant contamination.