Fonseca, Renata Garcia [UNESP]Cruz, Carlos Alberto dos Santos [UNESP]Adabo, Gelson Luis [UNESP]2014-05-272014-05-272004-07-01Pesquisa odontologica brasileira = Brazilian oral research, v. 18, n. 3, p. 228-232, 2004.1806-8324http://hdl.handle.net/11449/67791During the cementation of metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. This study evaluated the influence of chemical activation compared with dual-curing (chemical and light activation), on the hardness of four dual-curing resin cements. In a darkened environment, equal weight proportions of base and catalyst pastes of the cements Scotchbond Resin Cement, Variolink II, Enforce and Panavia F were mixed and inserted into moulds with cavities of 4 mm in diameter and 2 mm in height. Subsequently, the cements were: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated (dual-curing = dual-cured groups). The Vickers hardness number was measured at 1 hour, 24 hours and 7 days after the start time of cements' spatulation. For all the cements, the hardness values of self-cured groups were lower than those of the respective dual-cured groups at 1 hour and 24 hours. At 7 days, this behavior continued for Variolink II and Panavia F, whilst for Scotchbond Resin Cement and Enforce there was no statistical difference between the two activation modes. All cements showed a significant increase in their hardness values from 1 hour to 7 days for both activation modes. Of the self-cured groups, Scotchbond Resin Cement and Variolink II presented the highest and the lowest hardness values, respectively, for all three times tested. Within the limitations of this study, up to the time of 24 h, chemical activation alone was unable to promote similar hardness as to that obtained with dual-curing.228-232engbisphenol A bis(2 hydroxypropyl) ether dimethacrylateDuo Cementresin cementanalysis of variancechemistrycomparative studydental bondinghardnesshumanmaterials testingtimeAnalysis of VarianceBisphenol A-Glycidyl MethacrylateDental BondingHardnessHumansMaterials TestingResin CementsTime FactorsArtigo10.1590/S1806-83242004000300009S1806-83242004000300009Acesso aberto2-s2.0-287444364942-s2.0-28744436494.pdf304156134061589090564745448450382851339311179809