title: Polymerization shrinkage and contraction force of composite resin restorative inserted with "Megafiller".
abstract: This study quantified the contraction force and polymerization shrinkage of composite resins with/without beta-Quartz Glass Ceramic Inserts (BQCI) as "Megafiller". The materials used for the determination included a chemically cured composite and five light-cured composites. The system for measuring contraction force consisted of a transparent teflon tube for preparing the specimen, a small load cell, a dynamic strain gauge and a pen-recorder. After the composite was packed into the teflon mold, a BQCI (Type R3) was inserted through the opening and the specimen was cured. Linear polymerization shrinkage of the composites was measured every 10 seconds from the start of mixing or irradiation to 90 minutes by the mercury bath method. Three pieces each of BQCI (Type T3) were inserted in each specimen. The results suggested that BQCI was markedly effective in reducing polymerization shrinkage, but was not always effective in reducing the contraction force during polymerization.
authors.affiliation: Department of Biomaterials, Research Center for Biomedical Engineering, Kyoto University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tani
authors.forename: T
authors.initials: T
authors.lastname: Nambu
authors.forename: A
authors.initials: A
authors.lastname: Ishikawa
authors.forename: S
authors.initials: S
authors.lastname: Katsuyama
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate; D003188:Composite Resins / Q000737:chemistry*; D003793:Dental Restoration, Permanent / Q000379:methods*; D003799:Dental Stress Analysis; D005898:Glass; D008422:Materials Testing; D010316:Particle Size; D011140:Polyurethanes / Q000737:chemistry; D011791:Quartz; D019279:Resin Cements
chemical_list: D000180:Acrylic Resins; C029849:Clearfil Bonding Agent; C029012:Composite Dental Resin; D003188:Composite Resins; D011140:Polyurethanes; D019279:Resin Cements; C087764:Restolux SP 2; C074539:Palfique Light; C065771:P50 composite resin; C074669:Clearfil Photo Bond; D011791:Quartz; D017438:Bisphenol A-Glycidyl Methacrylate