Three point bending strength of in-ceram sinterized with colloidal alumina

Objectives: The aim of this study was to investigate the effect of use of a colloidal alumina/inorganic binder on the shear strength of sinterized In-Ceram core material. Methods: Two sample groups A. Conventional In-ceram material, B. In-Ceram powder combined with colloidal alumina binder with samples at 2x4x25 mm dimensions were prepared. The samples were subjected to three-point bending test and the fracture surfaces were examined with SEM at x600 and x2000 magnifications. The data were evaluated statistically with t-test. Results: The three-point bending test revealed mean values of A=642.5 N and B=776 N (P=0.001) and lower micro porosities were observed with B group samples. Conclusions: The high bending strength values and lower micro porosities obtained with this trial system are promising in fabrication of posterior all-ceramic restorations with lower fracture risk.