Flexural Strength Comparison of EQUIA Forte versus Fuji II LC

Objectives: Test commercial claim that EQUIA Forte exhibits "increased flexure strength" using a standardized 3-point bending test. Determine if introduction of ultrafine, highly reactive glass particles dispersed within conventional Glass Ionomer (GI) Structure makes it less moisture sensitive.
Methods: 160 specimens were equally divided, and given four different treatments: 1) 500 thermocycles with resin coating, 2) 500 thermocycles without resin coating, 3) ddH₂O at 37°C for 24-hours without resin coating, 4) air dried for 24-hours without resin coating. Each treatment contained equal groups (n=20) for both materials. We conducted a standardized 3-point bending test on all specimens with an Instron machine.
Results: Fuji II LC has a superior flexural strength compared to EQUIA Forte with (p<0.05) and without (p<0.05) a resin coating after 500 cycles in microClimate humidity chamber. Fuji II LC has a superior flexural strength compared to EQUIA Forte when stored in a 37°C ddH₂O bath without resin coating for 24-hours (p<0.05). Fuji II LC has a superior flexural strength compared to EQUIA Forte when air cured without resin coating for 24-hours (p<0.05). Resin coatings used with both RMGI materials exhibited higher flexural strength (p<0.05).
Conclusions: EQUIA Forte is more susceptible to moisture and temperature cycling. Fuji II LC exhibits a smoother surface with reduced cracks, voids, and clumps compared to EQUIA Forte with and without a resin coating.