title: Influence of 30% hydrogen peroxide bleaching on compomers in their surface modifications and thermal expansion.
abstract: The surface modifications and the coefficient of thermal expansion of compomers after treatment with a 30% hydrogen peroxide bleaching agent were investigated. Three compomers (Compoglass F, Elan and F2000) were nonbleached and bleached for 1 and 3 days. The surface modification and the coefficient of thermal expansion of each bleached compomer were evaluated using a scanning electron microscope and a thermomechanical analyzer, respectively. As a result, Compoglass F and Elan showed slight surface degradation, whereas F2000 showed many cracks on its surface and these cracks were not observed in Compoglass F and Elan. Bleached Elan and F2000 has changed to the extent where their the coefficient of thermal expansion increased compared with those of nonbleached specimens. In addition, bleached compomers showed a strong inverse correlation between the coefficient of thermal expansion and the volume percent of filler.
authors.affiliation: Department of Dental Materials, College of Dentistry, Pusan National University, Pusan 602-739, Korea.
authors.forename: Choong-Bo
authors.initials: CB
authors.lastname: Jung
authors.forename: Hyung-Il
authors.initials: HI
authors.lastname: Kim
authors.forename: Kyo-Han
authors.initials: KH
authors.lastname: Kim
authors.forename: Yong Hoon
authors.initials: YH
authors.lastname: Kwon
mesh_terms: D000704:Analysis of Variance; D020770:Compomers / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry; D006358:Hot Temperature; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016877:Oxidants / Q000737:chemistry*; D013223:Statistics as Topic; D013314:Stress, Mechanical; D013499:Surface Properties; D013816:Thermodynamics; D013997:Time Factors; D014073:Tooth Bleaching
chemical_list: C105428:Compoglass; D020770:Compomers; D003188:Composite Resins; D003764:Dental Materials; C472110:Elan (compomer); C118368:F2000 cement; D005899:Glass Ionomer Cements; D016877:Oxidants; D006861:Hydrogen Peroxide