title: Color stability of composites subjected to accelerated aging after curing using either a halogen or a light emitting diode source.
abstract: The purpose of this study was to evaluate, in vitro, the color stability of three composite resins of two different shades (A3 and C3) cured with either a quartz tungsten halogen (QTH) or a light emitting diode (LED) source. Forty specimens (20 x 2 mm) were prepared for each composite (Tetric Ceram, Heliomolar and Esthet-X), being 20 for each shade. In each group, 10 specimens were light-cured using the QTH unit and 10 with the LED source. The shade of the materials was evaluated before and after submitting the specimens to artificial accelerated aging (4 h UV-B/4 h condensing vapor), using a reflection spectrophotometer. deltaE means were calculated and analyzed statistically by 2-way ANOVA and Tukey's test at 5% significance level. Both A3 and C3 shades of Esthet-X composite resin showed the lowest color change when cured with the QTH light, while Tetric C3 cured with the QTH light showed the highest color change.
authors.affiliation: School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil. ferpanzeri@forp.usp.br
authors.forename: Fernanda de Carvalho Panzeri
authors.initials: Fde C
authors.lastname: Pires-de-Souza
authors.forename: Lucas da Fonseca Roberti
authors.initials: Lda F
authors.lastname: Garcia
authors.forename: Hisham Mohamad
authors.initials: HM
authors.lastname: Hamida
authors.forename: Luciana Assirati
authors.initials: LA
authors.lastname: Casemiro
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry / Q000528:radiation effects; D003116:Color; D003188:Composite Resins / Q000737:chemistry / Q000528:radiation effects*; D055117:Curing Lights, Dental / Q000145:classification*; D003764:Dental Materials / Q000737:chemistry / Q000528:radiation effects*; D003775:Dental Polishing; D006801:Humans; D055115:Light-Curing of Dental Adhesives / Q000295:instrumentation / Q000379:methods*; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry / Q000528:radiation effects; D011140:Polyurethanes / Q000737:chemistry / Q000528:radiation effects; D013053:Spectrophotometry; D013499:Surface Properties; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; D003188:Composite Resins; D003764:Dental Materials; C466112:Esthet-X; C513708:Heliomolar; D011108:Polymers; D011140:Polyurethanes; C121818:Tetric ceram