title: Adhesion after erbium, chromium:yttrium-scandium-gallium-garnet laser application at three different irradiation conditions.
abstract: The aim of this study was to investigate whether distinct cooling of low fluence erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation would influence adhesion. Main factors tested were: substrates (two), irradiation conditions (three), and adhesives (three). A 750 microm diameter tip was used, for 50 s, 1 mm from the surface, with a 0.25 W power output, 20 Hz, energy density of 2.8 J/cm(2) with energy per pulse of 12.5 mJ. When applied, water delivery rate was 11 ml/min. The analysis of variance (ANOVA) showed that laser conditioning significantly decreased the bond strength of all adhesive systems applied on enamel. On dentin, laser conditioning significantly reduced bond strength of etch-and-rinse and one-step self-etch systems; however, laser irradiation under water cooling did not alter bonding of two-step self-etching. It may be concluded that the irradiation with Er,Cr:YSGG laser at 2.8 J/cm(2) with water coolant was responsible for a better adhesion to dentin, while enamel irradiation reduced bond strength, irrespective of cooling conditions.
authors.affiliation: Operative Dentistry Department, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes, 2227, Cidade Universitária, São Paulo, SP, Brazil.
authors.forename: Sérgio Brossi
authors.initials: SB
authors.lastname: Botta
authors.forename: Patricia Aparecida
authors.initials: PA
authors.lastname: da Ana
authors.forename: Denise Maria
authors.initials: DM
authors.lastname: Zezell
authors.forename: John M
authors.initials: JM
authors.lastname: Powers
authors.forename: Adriana Bona
authors.initials: AB
authors.lastname: Matos
mesh_terms: D000268:Adhesiveness / Q000528:radiation effects*; D000818:Animals; D002417:Cattle; D001840:Dental Bonding; D003743:Dental Enamel; D003804:Dentin; D066298:In Vitro Techniques; D053844:Lasers, Solid-State; D013718:Tensile Strength; D014867:Water
chemical_list: D014867:Water