title: Fluoride release and mechanical properties after 1-year water storage of recent restorative glass ionomer cements.
abstract: OBJECTIVE
  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).
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors: Advanced Biomaterials, Department of Restorative Sciences, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, Japan.
authors: Maho
authors: M
authors: Shiozawa
authors: Oral Biomaterials Engineering, Course of Oral Health Engineering, School of Oral Health Care Sciences, Faculty of Dentistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan. takahashi.bmoe@tmd.ac.jp.
authors: Hidekazu
authors: H
authors: Takahashi
authors: Oral Biomaterials Engineering, Course of Oral Health Engineering, School of Oral Health Care Sciences, Faculty of Dentistry, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
authors: Naohiko
authors: N
authors: Iwasaki
mesh_terms: D001696:Biomechanical Phenomena; D005459:Fluorides / Q000737:chemistry*; D005899:Glass Ionomer Cements; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D014867:Water
chemical_list: D005899:Glass Ionomer Cements; D014867:Water; D005459:Fluorides
references: J Dent Res. 1993 Aug;72(8):1257-62
references: 8360372
references: J Dent. 2011 Dec;39(12):834-40
references: 21945449
references: Biomaterials. 1998 Mar;19(6):485-94
references: 9645554
references: J Dent Res. 1984 Feb;63(2):158-60
references: 6582098
references: J Mater Sci Mater Med. 2003 Oct;14(10):869-73
references: 15348524
references: Aust Dent J. 2011 Jun;56 Suppl 1:23-30
references: 21564113
references: Dent Mater. 2001 Jan;17(1):34-9
references: 11124411
references: Dent Mater. 2010 Jan;26(1):1-6
references: 19804903
references: Dent Mater. 2003 Jun;19(4):286-90
references: 12686292
references: Biomaterials. 1998 Dec;19(24):2269-75
references: 9884039
references: Eur J Oral Sci. 2002 Apr;110(2):175-8
references: 12013563
references: Quintessence Int. 1997 Nov;28(11):705-14
references: 9573860
references: Adv Dent Res. 1992 Sep;6:44-9
references: 1292462
references: Biomaterials. 1998 Mar;19(6):479-83
references: 9645553
references: Dent Mater. 1998 Nov;14(6):441-7
references: 10483407
references: Biomaterials. 1998 Mar;19(6):521-7
references: 9645558
references: Dent Mater. 2007 Mar;23(3):343-62
references: 16616773
references: Biomaterials. 2003 Oct;24(22):4063-9
references: 12834602