title: Effects of storage, thermal and load cycling on a new reinforced glass-ionomer cement.
abstract: The objective of this in-vitro study was to determine the influences of storage, thermal and load cycling as well as combinations of these treatment procedures on the microleakage patterns of a new 'condensable' silver reinforced restorative glass-ionomer cement (Shofu Hi-Dense). Class II preparations with gingival margins in dentine were made on 50 freshly extracted, non-carious molar teeth and restored with Shofu Hi-Dense according to the manufacturer's instructions. The restorations were subsequently stored for 1 week, finished and randomly assigned into five groups of 10 and treated as follows: Group 1 - control (uncycled); Group 2 - thermocycled; Group 3 - mechanically load cycled; Group 4 - three months storage, uncycled; Group 5 - three months storage, thermal and load cycled. The storage medium throughout the experiment was artificial saliva at 37 degrees C. All treatment procedures had no significant influence on microleakage at the enamel-cement interface. These treatment modalities, however, resulted in a significant increase in leakage at the dentine-cement interface. With the exception of the 1 week storage, uncycled group, the dentine-cement interface had significantly greater leakage than the enamel-cement interface.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, National University of Singapore.
authors.forename: A U
authors.initials: AU
authors.lastname: Yap
mesh_terms: D016722:Cermet Cements / Q000737:chemistry*; D003743:Dental Enamel; D003763:Dental Leakage; D003804:Dentin; D004356:Drug Storage; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D012464:Saliva, Artificial; D012834:Silver; D016474:Weight-Bearing
chemical_list: D016722:Cermet Cements; D012464:Saliva, Artificial; C101939:Shofu High Dense; D012834:Silver