title: Influence of Photoinitiator and Light-Curing Source on Bond Strength of Experimental Resin Cements to Dentin.
abstract: This study evaluated the bond strength (BS) of experimental resin cements formulated with different photoinitiators when activated by two kinds of light-curing units (LCUs) through a ceramic material. Seven resin blends with different camphorquinone (CQ) and/or phenylpropanedione (PPD) concentrations (weight) were prepared: C5: 0.5% CQ; C8: 0.8% CQ; P5: 0.5% PPD; P8: 0.8% PPD; C1P4: 0.1% CQ and 0.4% PPD; C4P1: 0.4% CQ and 0.1% PPD; C4P4: 0.4% CQ and 0.4% PPD. Two LCUs were used: one quartz-tungsten-halogen (QTH - 850 mW/cm²) and one light-emitting diode (LED - 1300 mW/cm²). The microtensile bond strength of each blend was assessed. Data were submitted to two-way ANOVA and Tukey's test (α=0.05). The BS values did not exhibit significant differences for LCUs, regardless of the photoinitiator type. Three cements showed significant differences: P5 and C5 had higher BS with QTH, and C4P1 with LED. For QTH, P5 showed the highest and C1P4 the lowest BS. For the LED, C4P1 showed the highest BS of all the cements. The results indicated that PPD was a viable alternative in the formulation of photocured resin cements, reducing or eliminating CQ that is yellowish without impairing the bond strength. Furthermore, both LED and QTH were effective in curing resin cements that contain PPD or CQ.
authors.affiliation: Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, Universidade Estadual de Campinas, Piracicaba, SP, Brazil.
authors.forename: Dario Raimundo
authors.initials: DR
authors.lastname: Segreto
authors.affiliation: Department of Restorative Dentistry, Dental Materials Division, Universidade Estadual do Oeste do Paraná, Cascavel, PR, Brazil.
authors.forename: Fabiana Scarparo
authors.initials: FS
authors.lastname: Naufel
authors.affiliation: Dental School, Universidade Santo Amaro, São Paulo, SP, Brazil.
authors.forename: William Cunha
authors.initials: WC
authors.lastname: Brandt
authors.affiliation: Dental School, Universidade Norte do Paraná, Londrina, PR, Brazil.
authors.forename: Ricardo Danil
authors.initials: RD
authors.lastname: Guiraldo
authors.affiliation: Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, Universidade Estadual de Campinas, Piracicaba, SP, Brazil.
authors.forename: Lourenço
authors.initials: L
authors.lastname: Correr-Sobrinho
authors.affiliation: Department of Restorative Dentistry, Dental Materials Division, Piracicaba Dental School, Universidade Estadual de Campinas, Piracicaba, SP, Brazil.
authors.forename: Mário Alexandre Coelho
authors.initials: MA
authors.lastname: Sinhoreti
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D055117:Curing Lights, Dental; D001840:Dental Bonding; D003804:Dentin / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning
chemical_list: D003188:Composite Resins