Porcelain adherence to dental cast CP titanium: effects of surface modifications

Improvement in Ti-porcelain bonding by SiO2 modification of titanium surface through cast method

“…In group C, SEM shows that Ti-porcelain had a compacted interface, Ti-Si compounds and SiO 2 on the surface of titanium might play an importtant role. While subsurface oxidation occurred in control groups, that mean titanium was strongly oxidized during sintering, these findings were in good agreement with previous investigations 10,32,33) , especially in group S. EDS analysis revealed the intensity profiles of major elements of the substrate and bonding agent at the Ti-porcelain interface. Based on these intensity profiles, it can be inferred that there is diffusion of bonding agent's elements into titanium, wherein the diffusion happens at the interface.…”

“…Oxidation of Ti leads to a thick, loosened oxide layer [4][5][6] . Various surface treatments have been used to avoid the oxidation and to improve Ti-porcelain bonding strength, such as sandblasting 7,8) , chemical agent bath 9,10) , and the application of intermediate coating [11][12][13][14][15] . Sandblasting is ordinarily used for preparing metal substrates with surface irregularities.…”

Evaluation of interface characterization and adhesion of glass ceramics to commercially pure titanium and gold alloy after thermal- and mechanical-loading

“…Several authors considered the shear test as the most adequate method to measure bond between the metal and ceramics [2,8,11,26,31,32]. However other authors [10,12,17,20,33,34] suggest the threepoint-flexure test, four-point-flexure test [28] or biaxial flexure test [1]. The shear test used was highly reliable, because it is based on minimal experimental variables and creates less residual stress at metal-ceramic interface, where the oblique forces are also minimized.…”

Effect of sandblasting conditions on alumina retention in representative dental alloys

“…Each grit acts on the surface as a tiny plowshare creating a long shallow fissure, which creates tensile stresses at the adjacent surface layers of the material. Attempts by the underlying material layers to regain their original form then creates residual compressive stresses 7) , a phenomenon that has been verified experimentally (at least for Ti castings) by XRD analysis 8) . Theoretically, these residual stresses should relax during porcelain firing and transform into tensile stresses due to mismatch in thermal expansion coefficients between dental alloys and ceramics 9,10) .…”