Acid erosion, surface topography, and fluoride release of glass ionomer cements subjected to erosive challenge.

To evaluate and compare the acid erosion resistance, surface topography, and fluoride release of restorative glass ionomer cements (GICs) subjected to erosive challenge. Specimens (n=6) of Vidrion R® (VD), Maxxion R® (MA), Vitro Molar® (VM), and GlasIonomer FX ULTRA® (GI) were prepared and stored in water at 5°C/24h. Baseline measurements of thickness, weight, and surface roughness (linear - Ra; volumetric - Sa) were obtained using a non-contact 3D profilometer. Specimens were immersed in 30 mL of a lactic acid buffer (pH 2.74) at 37°C/24h, after which final thickness (eroded depth), mass (eroded mass), and surface roughness were measured. Fluoride release was evaluated in duplicate using a calibrated fluoride-specific electrode. Data were analyzed using Jamovi 2.2.5 (p<0.05). All GICs showed a reduction in thickness; however, only VM exhibited an eroded depth below 0.17 mm (0.10 ± 0.03 mm, per ISO standards). Regarding mass loss, VD experienced the highest reduction and VM the lowest (p<0.05), with GI and MA showing similar losses (p>0.05). Regarding surface roughness, VD showed a reduction in Ra, whereas the other GICs showed increases (p>0.05). All specimens demonstrated a significant increase in Sa, with MA showing the greatest change (p<0.05). In fluoride release, MA and VD had the highest values (98.6 ± 11.8 and 91.4 ± 8.16), GI was intermediate (66.1 ± 4.12), and VM had the lowest (38.4 ± 9.97) (p<0.05). Although all products released fluoride and underwent significant changes in thickness, mass, and surface roughness under erosive challenge, only VM demonstrated adequate acid erosion resistance according to ISO standards.