Behavior of four dental cements in strength of mechanical properties

The dental cements are used, routinely, to fixation of restorative dental and responsible for filling the interface between the tooth and a restoration, therefore they must present satisfactory mechanical properties, in order to support the masticatory forces and occlusal loads in the oral cavity. Objectives: Being thus, the purpose of this work was to evaluate four dental cements (a phosphate zinc, a red copper phosphate zinc, a glass-ionomer and a resin cement), in relation to the punch shear strength, axial and diametral compression strength. Methods: For the punch shear assay, had been made specimens in a matrix in ring form with dimensions of 14mm of internal diameter and 1,5 mm of height that allowed to get a disc or currency of the materials with these dimensions which was connected in a proper device for the test. For the axial compressive assay had been followed the specifications of "ADA n˚96” and “ISO 9917:1(E)” whose specimen is of cylindrical format with dimensions of 6 mm of height for 4 mm of diameter. The tensile diametral assay, not exactly presenting specific norms for dental cements, followed the dimensions of the specimen for the axial compressive assay. Ten specimens of each material were evaluated in the periods of 1 and 24 hours. Results: Had been made statistic analysis with the two-way ANOVA, followed of the comparative tukey test with p< 0,05. Conclusions: The resin cement obtained the highest values of strength for the three tests and the glass-ionomer cement obtained the lowest values of strength among all the materials and different periods.