Effect of relative humidity on bond strength of self-etching adhesives to dentin.
OBJECTIVE
The aim of the study was to investigate the effect of the relative humidity of the ambient air on the dentin bonding efficiency of four self-etching primer adhesives.


METHODS
Three commercially available self-etching primer adhesives, AQ Bond, Fluorobond, One-Up Bond F, and one experimental all-in-one adhesive, AC-Bond, were selected. Peripheral plane dentin surfaces of human molars were prepared with wet SiC paper. Eight specimens were prepared for each of the adhesives and each of the following six conditions prior to application of the bonding agents and a hybrid-type resin composite material: air dried, wet, or stored for 1 h at 33%, 50%, 75%, and 100% relative humidity (RH). Shear bond strength (SBS) was determined after 24 h of storage in water at 37 degrees C.


RESULTS
None of the adhesives showed statistically significant differences in SBS between the experimental conditions. AC Bond, AQ Bond, and Fluorobond were equally effective with an average SBS of 19.0 MPa, whereas One-Up Bond F showed a significantly lower mean SBS of 11.5 MPa.


CONCLUSIONS
The self-etching primer adhesives tested are unaffected by the degree of dentin wetness or ambient air humidity exposure prior to application. Unless considered necessary for other clinical reasons, use of rubber-dam is not compulsory.
Werner
J Finger
JF
Department of Preclinical Dentistry, School of Dental Medicine, University of Cologne, Germany. wjfinger@aol.com
Tani
Chihiro
C
D000269:Adhesives / Q000737:chemistry; D000704:Analysis of Variance; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003804:Dentin; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D005460:Fluorides, Topical / Q000737:chemistry; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D018709:Statistics, Nonparametric; D014867:Water
C453842:AQ bond; D000269:Adhesives; D003738:Dental Cements; D017220:Dentin-Bonding Agents; D005460:Fluorides, Topical; C072652:FluoroBond; D008689:Methacrylates; C446260:One-Up-Bond F; D019279:Resin Cements; D014867:Water