THE EFFECT OF DIFFERENT DIE MATERIAL, CEMENT AND STORAGE MEDIA ON FRACTURE STRENGTH OF ZIRCON SUBSTRUCTURAL CERAMIC

Aim: the aim of this study was to evaluate the effect of different elastic modulus die material, cement and storage on the fracture resistance of zirconia substructure. material and method: as a die infrastructure material, dentin( 40 non-carious upper 1st premolar), cr-co and composite resin was used. the teeth was prepared by the cervico-occlusal taper angle and shoulder step finish line. the measurement was taken of dentin die using a silicone-based impression material and dublicated dies was obtain from cr-co metal and light-curing composite material. 60 dies was prepared three different material. zirconia substructure was prepared on the dies. prepared dies was divided into two groups. zirconia substructure was cemented with conventional polycarboxylate cement on the first group and second group was non-cemented. before testing samples were incubated at 37 ° c in distilled water and coke for a week. fracture resistance test was performed by universal testing machine. compression load was applied with 0.5mm/dk head speed until the substructure was broken. the obtained values was recorded in newton (n). while the data were analyzed, two wat anova test and lsd test that one of post hoc multipl comparison tests were used. p<0.05 was considered statistically significant for results. results: highest fracture resistance value (5790.5 n) were found in zirconium substructure materials on the dental die. substructure on the composite metal die were followed (4563.3 n 3909.0 n) the dental die. the difference between fracture resistance of die material was statistically significant. (p<0,05) the differences between cemented and non-cemented group was statistically significant. (p<0.001) the difference between different solution groups was no statistically significant. (p>0.05) conclusion: acording to die material, the highest fracture resistance value was found in dentin and the lowest value was found in composite. the fracture resistances value of cemented group on the zirconia substructure materials were higher than non-cemented groups. there were no differences in fracture resistance of substructure put in different solution.