Using x-ray spectroscopy the inorganic contents of the interface tooth restoration of conventional and gamma-2-reduced amalgam fillings were analysed after short and long clinical application. Qualitative difference did not exist between interface layer of both amalgam types. The amalgam elements mercury, silver and copper were not detected, but tin occurred everywhere. Zinc and oxygen were frequently analysed in the interface layer. Calcium, phosphorus, sodium and magnesium were detected, too.