title: Voids formation along the bonding interface between a smeared dentin surface and all-in-one adhesives.
abstract: It has been reported that the adhesive resin layer of all-in-one adhesives is permeable and allows the formation of a water channel or water tree. The effects of a smear layer on the ultra-structure of bonding interface created with three all-in-one adhesives and a resin composite were evaluated in this study. Dentin surface was ground with of 180-, 600-, or 2000-grit SiC paper to produce different smear layer thickness. The bonding interfaces were observed under a transmission electron microscope without demineralization. Voids of various sizes and water channels were found at the bottom of the adhesive resin layer along the bonding interface of SiC 180-grit dentin, while SiC 2000-grit dentin did not produce any voids. The results showed that the voids were possibly related to water that had penetrated from the underlying dentin. A smear layer may have an adverse influence on the bonding performance of all-in-one adhesives to dentin.
authors.affiliation: Department of Dentistry for Children and Disable Person, Division of Oral Functional Science, Hokkaido University Graduate School of Dental Medicine, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan. eyoshida@den.hokudai.ac.jp
authors.forename: Eiji
authors.initials: E
authors.lastname: Yoshida
authors.forename: Shigeru
authors.initials: S
authors.lastname: Uno
mesh_terms: D000269:Adhesives; D000704:Analysis of Variance; D003188:Composite Resins; D001840:Dental Bonding; D003804:Dentin; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents; D006801:Humans; D008689:Methacrylates; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D016062:Porosity; D019279:Resin Cements; D016369:Smear Layer; D018709:Statistics, Nonparametric; D014867:Water
chemical_list: C453842:AQ bond; D000269:Adhesives; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C498353:G-Bond; D008689:Methacrylates; D019279:Resin Cements; C477386:iBond; D014867:Water