title: Effects of bleaching agent on physical and aesthetic properties of restorative materials.
abstract: To investigate the effects of bleaching agent on microhardness, color and light transmission of different restorative materials. Specimens (n=20) of Tetric EvoCeram (TEC), Tetric EvoCeram Bulk Fill (TECBF) and Equia Fill (EQUIA) were treated with either 40% hydrogen peroxide Opalesence Boost or destilled water for 45 min. Specimens were stained in tea solution or stored in deionized water for one and two weeks. Color, microhardness and light transmission were monitored at the baseline, after the bleaching and after the tea immersion or storage in deionized water. After the bleaching a significant reduction in surface microhardness (p<0.001) was recorded for all materials. Clinically visible color change (ΔE>3) was observed after the bleaching and after treatment in tea solution, but only in EQUIA samples. The absorption coefficient was the largest for the samples stained in tea solution. Bleaching can affect the microhardness and color of fillings; therefore, they should be sometimes replaced.
authors.affiliation: Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb.
authors.forename: Eva
authors.initials: E
authors.lastname: Klaric Sever
authors.forename: Nika
authors.initials: N
authors.lastname: Simenc
authors.forename: Mario
authors.initials: M
authors.lastname: Rakic
authors.forename: Hrvoje
authors.initials: H
authors.lastname: Skenderovic
authors.forename: Ivan
authors.initials: I
authors.lastname: Sever
authors.forename: Zrinka
authors.initials: Z
authors.lastname: Tarle
mesh_terms: D057886:Bleaching Agents; D003116:Color; D004954:Esthetics; D006861:Hydrogen Peroxide; D008422:Materials Testing; D010545:Peroxides; D014073:Tooth Bleaching; D014508:Urea
chemical_list: D057886:Bleaching Agents; D010545:Peroxides; D014508:Urea; D006861:Hydrogen Peroxide