Febriani, M. et al. 2026. The Difference in Hardness of Heat-Cured Acrylic Resin Before and After Immersion in Various Grape Fruit Extracts. Formosa Journal of Science and Technology. 5, 10 (Nov. 2026), 2685–2692. DOI:https://doi.org/10.55927/fjst.v5i10.4.