title: Influence of warm air-drying on enamel bond strength and surface free-energy of self-etch adhesives.
abstract: We examined the effect of warm air-drying on the enamel bond strengths and the surface free-energy of three single-step self-etch adhesives. Bovine mandibular incisors were mounted in self-curing resin and then wet ground with #600 silicon carbide (SiC) paper. The adhesives were applied according to the instructions of the respective manufacturers and then dried in a stream of normal (23°C) or warm (37°C) air for 5, 10, and 20 s. After visible-light irradiation of the adhesives, resin composites were condensed into a mold and polymerized. Ten samples per test group were stored in distilled water at 37°C for 24 h and then the bond strengths were measured. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The enamel bond strengths varied according to the air-drying time and ranged from 15.8 to 19.1 MPa. The trends for the bond strengths were different among the materials. The value of the γS⁺ component increased slightly when drying was performed with a stream of warm air, whereas that of the γS⁻ component decreased significantly. These data suggest that warm air-drying is essential to obtain adequate enamel bond strengths, although increasing the drying time did not significantly influence the bond strength.
authors.affiliation: Department of Operative Dentistry, Nihon University School of Dentistry, Tokyo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Shiratsuchi
authors.forename: Akimasa
authors.initials: A
authors.lastname: Tsujimoto
authors.forename: Toshiki
authors.initials: T
authors.lastname: Takamizawa
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Furuichi
authors.forename: Keishi
authors.initials: K
authors.lastname: Tsubota
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Kurokawa
authors.forename: Masashi
authors.initials: M
authors.lastname: Miyazaki
mesh_terms: D000269:Adhesives / Q000737:chemistry*; D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D058868:Compressed Air; D001840:Dental Bonding / Q000379:methods*; D003743:Dental Enamel / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D013499:Surface Properties
chemical_list: D000269:Adhesives; D017220:Dentin-Bonding Agents; D019279:Resin Cements
keywords: bond strength; enamel; one-step self-etch adhesive; surface free-energy; warm air-drying