الفهرس 
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Abstract
This study aimed to evaluate the laboratory performance of 2 laminate veneers ceramic materials.
The study was comprised of two laboratory tests: (a) shear bond testing and (b) biaxial flexural strength. Both tests were made to evaluate the effect of different surface treatments on the ceramic materials used in the study.
For shear bond testing, 40ceramic discs (4.0 mm x 2.0 mm) of both materials (IPS-E.max press, VM7) were randomly divided into 4 subgroups according to the surface treatments used forming subgroups. The specimens of subgroup 1 were surface treated with phosphoric acid and silane coupling agent, while those of subgroup 2 were surface treated with phosphoric acid and silane coupling agent and heat. The specimens of subgroup 3 were surface treated with Hydrofluoric acid and silane coupling agent, while those of subgroup 4 were surface treated with Hydrofluoric acid and silane coupling agent and heat. The fabricated discs were bonded to the enamel of cut upper incisor teeth forming the shear bond test specimens, which were then thermocycled and finally subjected to shear force on the universal testing machine till disc separation occurred. The value at which failure occurred was recorded for each specimen.
As for biaxial flexural strength test, 40 ceramic discs (10.0 mm x 1.2 mm) were fabricated from both ceramic materials used in the study and then divided into 4 subgroups as in shear test according to the surface treatments used. Each disc was subjected to biaxial force using a ball indenter by the universal testing machine till failure. The value at which each disc failed was recorded individually.