IADR Abstract Archives
Experimental tests for mechanical properties of glass ionomer cements.
Objectives: The aim of this study is to measure mechanical properties of the newer glass ionomers with three new experimental tests and to compare with compressive strength and flexural strength. The aim was to develop appropriate experimental methods for material testing in a new way that tries to imitate real clinical situation.
Methods: Six conventional newer glass ionomers were used in the study (Ketac Molar AC(3M Espe), Ketac Universal AC (3M Espe), Fuji IX GP (GC), Equia Forte (GC), IonoStar Plus (VOCO), Riva s.c.(SDI)) . Five different tests were performed to evaluate mechanical properties of GICs. Three new tests (edge stability (ES), ball on compressive (BC) and fracture resistant (FR)) were compared with compressive strength (CS) and flexural strength (FS). Ten specimens were fabricated with each material and for each size, in a total of 300 specimens. For CS, ES and BC samples were cylinders (d=4mm, h=6mm) and for FS samples were bars (2x2x25mm). Fracture resistance were measured on GIC class II fillings made on ceramic teeth with standardized cavities. All samples were stored in distilled water for 24 hours and then subjected to a diferent tests in a universal testing machine at a crosshead speed of 1 mm/min. The data were statistically analyzed using the ANOVA and post hoc Tukey test.
Results: Mean compressive strength values (MPa) were: 284.00 (24.90) and 264.46 (3.43) for the sample using Ketac Universal and Fuji IX. The higher values of flexural strength were obtained for Fuji IX 46.03 (8.15) and Ketac Universal 45.29(7.87) but it was not statistically significant difference. Ketac Universal showed higher value in ES tests 250.54 (22.88);p<0.05 and Fuji IX showed higher value in ball on compressive test 369.60(3.94) p<0.05. A higher variability in results was observed when the fracure resistant of GIC fillings were measured.
Conclusions: A higher variability in results were observed in FS measurements. All three new experimental test tried to mimic real clinical situations. ES test was the most reliable with the smallest variations and correlated with the compressive strength. Fracture resistant test need to be improved in order to decrease variability in results.
Methods: Six conventional newer glass ionomers were used in the study (Ketac Molar AC(3M Espe), Ketac Universal AC (3M Espe), Fuji IX GP (GC), Equia Forte (GC), IonoStar Plus (VOCO), Riva s.c.(SDI)) . Five different tests were performed to evaluate mechanical properties of GICs. Three new tests (edge stability (ES), ball on compressive (BC) and fracture resistant (FR)) were compared with compressive strength (CS) and flexural strength (FS). Ten specimens were fabricated with each material and for each size, in a total of 300 specimens. For CS, ES and BC samples were cylinders (d=4mm, h=6mm) and for FS samples were bars (2x2x25mm). Fracture resistance were measured on GIC class II fillings made on ceramic teeth with standardized cavities. All samples were stored in distilled water for 24 hours and then subjected to a diferent tests in a universal testing machine at a crosshead speed of 1 mm/min. The data were statistically analyzed using the ANOVA and post hoc Tukey test.
Results: Mean compressive strength values (MPa) were: 284.00 (24.90) and 264.46 (3.43) for the sample using Ketac Universal and Fuji IX. The higher values of flexural strength were obtained for Fuji IX 46.03 (8.15) and Ketac Universal 45.29(7.87) but it was not statistically significant difference. Ketac Universal showed higher value in ES tests 250.54 (22.88);p<0.05 and Fuji IX showed higher value in ball on compressive test 369.60(3.94) p<0.05. A higher variability in results was observed when the fracure resistant of GIC fillings were measured.
Conclusions: A higher variability in results were observed in FS measurements. All three new experimental test tried to mimic real clinical situations. ES test was the most reliable with the smallest variations and correlated with the compressive strength. Fracture resistant test need to be improved in order to decrease variability in results.