Dentin treatment effects on the bonding performance of self-adhesive resin cements.
The effects of dentin surface treatments on the microtensile bond strengths and on the interfacial characteristics of self-adhesive resin cements were investigated. Flat dentin surfaces were obtained from human molars and were treated as follows: (i) no treatment of dentin; (ii) 0.1 M EDTA scrubbed for 60 s; or (iii) 10% polyacrylic acid applied for 30 s. Three self-adhesive cements were used to lute composite overlays on deep-coronal dentin surfaces in the presence of simulated pulpal pressure (15 cm of H(2)O). Bonded specimens were cut into beams 1 mm thick and stressed in tension until failure. Fractured sticks were examined under a scanning electron microscope. Additional specimens were stained with Masson's trichrome and observed under light microscopy for interfacial evaluations. The bond strength to dentin of the hydrophobic and solvent-free cement (RelyX Unicem) was unaffected by the tested dentin treatments. The bond strength of the 2-hydroxyethyl methacrylate (HEMA)-based cement (Bis-Cem) decreased after treatment of dentin with EDTA and/or polyacrylic acid. The hydrophilic and water-containing cement (G-Cem) attained a higher bond strength when luted on polyacrylic acid-conditioned dentin. In conclusion, smear layer removal, opening of dentinal tubules, and the water content of dentin differently influence the bond strengths and the interfacial characteristics of self-adhesive cement-dentin interfaces.
Department of Fixed Prosthodontics and Dental Materials, University of Siena, Policlinico Le Scotte, viale Bracci, Siena, Italy. claudiamazzitelli@yahoo.it
Claudia
C
Mazzitelli
Francesca
F
Monticelli
Manuel
M
Toledano
Marco
M
Ferrari
Raquel
R
Osorio
D000180:Acrylic Resins / Q000494:pharmacology; D003188:Composite Resins; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D003799:Dental Stress Analysis; D003804:Dentin / Q000187:drug effects* / Q000648:ultrastructure; D003806:Dentin Permeability / Q000187:drug effects; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D008422:Materials Testing; D019279:Resin Cements / Q000737:chemistry; D013718:Tensile Strength; D017155:Wettability
D000180:Acrylic Resins; C542562:BisCem cement; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C528107:G-Cem resin cement; C483701:Rely X Unicem; D019279:Resin Cements; C006903:carbopol 940; D004492:Edetic Acid