بررسی استحکام باند برشی گلاس آینومرهای Conventional و Modified Resin بر سطوح مینا، عاج و سمان

Introduction: According to appropriate characteristics of glass ionomer cementum and constant increase of its usage in restorative field, so comparison of conventional and resin- modified glass ionomers seems to be useful. This study was designed to determine the shear bond strength of conventional and resin- modified glass Ionomers on enamel, dentin and cementum. Methods: This was an experimental study. Totally 60 molar intact teeth were divided into six groups. In groups A and D the surface of enamel was prepared 1mm, in groups B and E, the preparation was continued until the surface of dentin was exposed and in groups F and C the surface of cementum was only refreshed. In groups A, B, and C conventional glass ionomer and in groups F, E, and D resin-modified glass ionomer was used. For each specimen a plastic cylinder with 2mm diameter and 3mm height was bonded on treated surface and the teeth were filled by the relevant glass ionomer. In groups F, E, and D glass ionomer was light cured for 40 seconds. specimens were loaded to failure in a universal testing machine Then statistical analysis was performed using one- way ANOVA and LSD test (P=0.05). Results: The mean shear bond strength of groups A, B, C, D, E and F were 17.25, 14.77, 15.37, 27.30, 57.80, 23.50 Mpa, respectively. The difference between shear bond strength of groups F, E, and D with groups A, B, and C was statistically significant (P=0/001). Conclusion: The shear bond strength of the resin-modified glass Ionomers was significantly higher than that of conventional glass ionomer in all three surfaces.