In vivo influence of residual moisture on microtensile bond strengths of one-bottle adhesives.
OBJECTIVE
This study evaluated the microtensile bond strengths of three dentin adhesives applied on clinically moist dentin or on dentin that was dried with air for 5 seconds. The null hypothesis to test was that the level of residual moisture does not influence bond strengths when restorations are placed in vivo.


METHODS
Twenty-four premolars scheduled to be extracted for orthodontic reasons from patients between the ages of 15 and 23 years were restored with one of the following adhesive systems followed by a mini hybrid composite resin: Excite (Ivoclar/Vivadent), an ethanol-based dentin adhesive; Prime & Bond NT (Dentsply/Caulk), an acetone-based dentin adhesive; and Single Bond (3M ESPE), an ethanol and water-based dentin adhesive. After extraction, the specimens were sectioned with a slow-speed diamond saw in two perpendicular directions to obtain sticks with a cross-section of 0.7 +/- 0.2 mm2. The specimens were attached to a Geraldeli device and fractured using a universal testing machine at a crosshead speed of 1 mm per minute.


RESULTS
For each dentin adhesive, there were no statistical differences between means for dry dentin versus moist dentin. Single Bond and Prime & Bond NT ranked in the same statistical subset regardless of the moisture condition of the substrate. Both Excite, dry, and Excite, moist, resulted in statistically lower bond strengths than Single Bond, moist, but similar to those of Single Bond, dry, Prime & Bond NT, moist, and Prime & Bond NT, dry.


CONCLUSIONS
In this study, the level of residual moisture did not influence microtensile bond strengths. Clinically, the degree of moisture left on the dentin surface upon rinsing off the etching gel may not be as relevant as previously reported in laboratory studies.
Perdigão
Jorge
J
Division of Operative Dentistry, Department of Restorative Sciences, University of Minnesota, Minneapolis, Minnesota, USA. perdi001@umn.edu
Geraldeli
Saulo
S
Carmo
André R P
AR
Dutra
Hélio R
HR
D000096:Acetone / Q000737:chemistry; D000134:Acid Etching, Dental; D000293:Adolescent; D000328:Adult; D000388:Air; D000704:Analysis of Variance; D001641:Bicuspid; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D016001:Confidence Intervals; D001840:Dental Bonding; D003804:Dentin / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013223:Statistics as Topic; D013696:Temperature; D013718:Tensile Strength; D014867:Water / Q000737:chemistry*
D003188:Composite Resins; D017220:Dentin-Bonding Agents; C420130:Excite cement; D008689:Methacrylates; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D012997:Solvents; C115612:single bond; D014867:Water; D000096:Acetone; D000431:Ethanol; D017438:Bisphenol A-Glycidyl Methacrylate