Influence on mechanical properties and fluoride ion release when powdery cellulose nanofibers are added to a conventional glass-ionomer restorative

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. Moreover, although cellulose nanofiber (CNF) is also 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 5 wt% and ageing it 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 at CNF approximately 4–5% is a promising reinforcement agent for conventional high-viscosity GIC.

2020年度

収集根拠 : 博士論文（自動収集）
資料形態 : テキストデータ
コレクション : 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
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. Moreover, although cellulose nanofiber (CNF) is also 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 5 wt% and ageing it 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 at CNF approximately 4–5% is a promising reinforcement agent for conventional high-viscosity GIC.
2020年度