title: Influence of oxygen inhibition on the surface free-energy and dentin bond strength of self-etch adhesives.
abstract: We compared the surface free-energies and dentin bond strengths of single-step self-etch adhesives with and without an oxygen-inhibited layer. The labial dentin surfaces of bovine mandibular incisors were wet ground with #600-grit silicon carbide paper. The adhesives were applied to the ground dentin, light-irradiated, and the oxygen-inhibited layer was either retained or removed with ethanol. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The dentin bond strengths of specimens with and without the oxygen-inhibited layer were measured. For all surfaces, the value of the estimated surface tension component was relatively constant at 35.5-39.8 mJ m(-2) . The value of the , Lewis acid component increased slightly when the oxygen-inhibited layer was removed, whereas that of the , Lewis base component decreased significantly. The bond strengths of the self-etch adhesives were significantly lower in specimens without an oxygen-inhibited layer (13.2-13.6 MPa) than in those with an oxygen-inhibited layer (17.5-18.4 MPa). These results indicate that the presence of an oxygen-inhibited layer in single-step self-etch adhesives with advanced photoinitiators promotes higher dentin bond strength.
authors: Department of Operative Dentistry, Nihon University School of Dentistry, Tokyo, Japan.
authors: Kensaku
authors: K
authors: Koga
authors: Akimasa
authors: A
authors: Tsujimoto
authors: Ryo
authors: R
authors: Ishii
authors: Masayoshi
authors: M
authors: Iino
authors: Mayumi
authors: M
authors: Kotaku
authors: Toshiki
authors: T
authors: Takamizawa
authors: Keishi
authors: K
authors: Tsubota
authors: Masashi
authors: M
authors: Miyazaki
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000465:Algorithms; D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D010100:Oxygen / Q000037:antagonists & inhibitors*; D058567:Photoinitiators, Dental / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D012997:Solvents / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D017155:Wettability
chemical_list: C515604:Clearfil Tri-S Bond; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C498353:G-Bond; D008689:Methacrylates; D058567:Photoinitiators, Dental; D011109:Polymethacrylic Acids; D019279:Resin Cements; D012997:Solvents; C020946:triethylene glycol dimethacrylate; D000431:Ethanol; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate; D010100:Oxygen