Diametral tensile strength of conventional glass ionomer cements with modified powder ratio for uses in atraumatic restorative treatment

Objective: To identify the diametral tensile strength of Brazilian brands of conventional glass ionomer cements (GIC) when modified powder ratio in their composition compared to each other, and with high viscosity glass ionomer cement for Atraumatic Restorative Treatment (ART). Methods: Experimental study with five groups (n=10 each) and specimens (2.5 mm in height and 5.0 mm in diameter), considering G1 (Maxxion R-MR), G2 (Vidrion R-VR) and G3 Vitro molar (VM-control) according to manufacturer recommending powder/liquid (1:1), G4 (MR) and G5 (VR) plus powder (2:1). The specimens were stored in an oven at 37 ± 1 ° C for 1 day. Diametral Tensile Test was performed by the Instron model 4444. Means differences were tested by Student´s T-Test (α = 5%). Results: There significant differences were in the means (standard deviation) of diametral tensile strength of MR (1:1) 4.24 (±1.47) and MR (2:1), 5.74 (±1.51) (p=0.039) and VR (1:1) 4.50 (±1.27) and VR (2:1) 6.20 (±1.89) (p=0.029). When comparing MR and VR (2:1) with MV (1:1) 4.82 (±1.17), VR 2: 1, 6.20 (±1.89) showed significant differences (p=0.0336). Conclusion: There was a significant increase in the means of diametral tensile strength of Brazilian brands conventional GICs when powder increment, approaching the performance observed by the high viscosity GIC.