In addition to selecting an appropriate color, the problem o f ufficiently strong bonding of the polymer layer to a metal cast also arises in procesing crowns and bridges to be veneered. The aim o f this research was to determine the impact o f the mechanical retention and its spacing, the opaquer applied, the method of sandblasting and the enviroment and time, on the bond between two polymer materials, with an appropriate metal pattern.The study was carried out on 400 completely equal metal patterns divided into groups, exposed to water storage and stored in a dry enviroment. Values o f bond strenghts were tested in combinations o f mechanical type bond with two polymer materials and two alloys. The strength of the retention bond was computed on the basis o f load values at the instant when the bond break occured. Minimum diameter beads give better retention then those of bigger diameter. The opaquer did not increase the adhesion between the polymer and material framework, whilst sandblasting of the metal surface, damp storage and type o f polymer material, did not have a significant effect on retention strength.