抄録
Although glass ionomer cement (GIC) has several favorable properties that may facilitate the management of deep carious lesions, some deficiencies still need to be overcome. Although cellulose nanofiber (CNF) is a plant-derived fiber material that has exhibited positive effects on the properties of GIC, there is lack of research on the addition of CNF to high-viscosity GIC. The objective of this study was to modify a conventional high-viscosity GIC restorative, Fuji IX GP-ExⓇ, with powdery CNF, and to evaluate its effect on the compressive strength (CS), flexural strength (FS), fracture toughness (FT), and fluoride release dose of the modified material during long-term aging. Samples were prepared by adding CNF (CellulostarⓇ) to the high-viscosity GIC at 0, 3, 4 and 5wt% and ageing it after mixing for up to 90 days in artificial saliva. The FS, FT and fluoride-ion release dose were significantly improved in the CNF modified GIC groups over time. However, no significant difference was observed in the CS. SEM observations showed that CNF has a high affinity for the GIC matrix, and that it aggregated and dispersed in the cured cement. Powdery CNF at approximately 4-5% is a promising reinforcement agent for conventional high-viscosity GIC. (J Osaka Dent Univ 2021; 55: 137-147)
