Influence of preoxidation cycle on the bond strength of CoCrMoSi-porcelain dental composites

► The influence of preoxidation heat treatment (PHT) on CoCrMoSi-porcelain bond strength was accessed. ► A mechanical and chemical evaluation of the interface was performed. ► PHT can account for the decreasing of CoCrMoSi alloys-porcelain bond strength. ► Alumina-blasting produces both a mechanical and a chemical effect on metal's surface. ► They converge in two complementary effects for metal-ceramic bond strength enhancement.