The last step of inlay and onlay fabrication, the cementation may cause occlusal changes which were not identified at try in phase. The aim was to compare the material film thickness of phosphate, carboxyl, glass ionomer (GIC) and composit cements in an in vitro study. 100 prefabricated inox pins were cemented in heavy bodied silicon (pin-)holes, 20 for each luting cement. During cementation a 751 gr force was applied to the cap of each pin. The results have shown the highest film thickness for phosphate cement, and the lowest for the composit cement. It has to be mentioned, that phosphate cement under constant pressure has had the best thickness in order avoid occlusal changes.