IN VITRO BEHAVIOR WITH DIFFERENT THICKNESSES ON STRUCTURES CERAMIC ZIRCONIUM DIOXIDE (Y-TZP) BEFORE SHEARING FORCES
DOI:
https://doi.org/10.15332/us.v11i1.1132Keywords:
Delamination, Zirconium, CeramicAbstract
Objective: To assess the performance of zirconium oxide (Y-TZP) ceramic coated with different thicknesses shear forces.
Methods: an In vitro experimental study was done with thirty zirconium dioxide cylinders coated with VITA VM 9 at different thicknesses (1.0 mm, 1.5 mm and 2.0 mm), they were subjected to shear forces. The control group consisted in metal-ceramic rods coated with VITA VM13. We evaluated the interface, the severity of delamination of the ceramic, the shape of the fracture, the type of material, the thickness of the ceramic and pottery effort measured in MPa. The variables were analyzed according to their nature and distribution; the tests used were Chi2, U. Mann Whitney and a logistic regression.
Results: 93.22% of the samples suffered delamination of the adhesive type. The 49.15% were zirconium dioxide samples. Minor faults were obtained on a sample of 47.46% and 18.64% in severe. The material could increase the severity of delamination (3.24 times more) but the difference was not statistically significant (OR 3.24 95% CI 0.91 – 1.16).
Conclusions: delamination of the ceramic is not directly proportional to the thickness. Furthermore, the zirconium dioxide presented low shear strength.
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