Fluoride release and mechanical properties after 1-year water storage of recent restorative glass ionomer cements

• Published in: Clinical oral investigations Vol. 18; no. 4; pp. 1053 - 1060
• Main Authors: Shiozawa, Maho, Takahashi, Hidekazu, Iwasaki, Naohiko
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2014; Springer Nature B.V
• Subjects: Biomechanical Phenomena; Dentistry; Fluorides - chemistry; Glass Ionomer Cements; Materials Testing; Medicine; Microscopy, Electron, Scanning; Original Article; Water; Surface hardness; Compressive strength; Glass ionomer cement; Long-term stability; Elemental analysis; Fluoride release
• ISSN: 1432-6981; 1436-3771
• DOI: 10.1007/s00784-013-1074-4

Objectives The objective of this study was to evaluate the relationships between fluoride release and mechanical properties after 1-year water storage of five recent restorative glass ionomer cements (GICs). Materials and methods Five GICs, FujiIX GP EXTRA (FEX), FujiIX GP (FIX), GlasIonomer FX-II (GFX), Ketac Molar Easymix (KME), and Riva Self Cure (RSC), were examined. Cumulative fluoride release, compressive strength, and surface hardness were measured up to 1-year storage ( n  = 5), and analyzed with one-way or two-way ANOVA and Tukey HSD test ( α  = 0.05). Elemental compositions before and after 1-year storage were also examined ( n  = 3). Results The amounts of fluoride release were significantly different among the products. The highest amount of fluoride release occurred during the first day. Then, the amount of fluoride release rapidly decreased and still continued until 1-year storage. Compressive strengths indicated that two main factors were significant (GFX < FEX = RSC < FIX < KME; 1 day < 1 week = 1 month = 3 months = 6 months = 1 year), but surface hardness showed a slightly different tendency (GFX = RSC < FEX = FIX = KME; 1 year < 1 day < 1 week = 1 month = 3 months = 6 months). Significant correlation was found between decrease of silicon and decrease rate of the surface hardness. Conclusions Fluoride releases were detected up to 1-year storage, but the mechanical properties slightly decreased due to decrease of Si after 1-year storage. Elution of Si instead of fluoride release was considered more critical to deteriorate the mechanical properties of GICs. Clinical relevance Fluoride released for 1-year water storage will contribute to secondary caries prevention. The amount of fluoride release did not affect these mechanical properties. These results indicate the usefulness of these GICs.