The nanoleakage phenomenon: influence of moist vs dry bonding.
OBJECTIVE
To assess the degree of nanoleakage of Class V preparations restored with three bonding agents using wet and dry bonding.


METHODS
Standardized Class V cavities were prepared in 66 human molars with cervical margins located in dentin. The composite was placed using one of three different dentin bonding agents with a moist or dry bonding technique (n = 11 per group). The teeth were stored in a 1% rhodamin-B solution for 24 h at 20 degrees C, then rinsed with water, embedded in methacrylate, and sectioned parallel to the long axis of the tooth, separating the restorations into two parts. A confocal laser scanning microscope (CLSM) was used to visualize the layer 10 microm under the prepared surface of the section. The lengths of the dye-penetrated pathways were measured, representing the amount of nanoleakage.


RESULTS
Differences in nanoleakage between the tested materials were proven to be statistically significant. The effect of drying had a significant influence on both the acetone-based and the ethanol-based material, but not on the water-based bonding resin.


CONCLUSIONS
Dentin drying may have an influence on nanoleakage, depending upon the nature of the individual bonding agent.
Pioch
Thomas
T
Department of Restorative Dentistry, University of Heidelberg, Germany. thomas_pioch@med.uni-heidelberg.de
Staehle
Hans Jörg
HJ
Wurst
Marcus
M
Duschner
Heinz
H
Dörfer
Christof
C
D000096:Acetone / Q000737:chemistry; D000134:Acid Etching, Dental; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D003737:Dental Cavity Preparation / Q000145:classification; D003743:Dental Enamel / Q000648:ultrastructure; D003763:Dental Leakage / Q000145:classification* / Q000473:pathology; D003804:Dentin / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D005456:Fluorescent Dyes; D005976:Glutaral / Q000737:chemistry; D006801:Humans; D018613:Microscopy, Confocal; D008963:Molar; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012235:Rhodamines; D012822:Silicon Dioxide; D012997:Solvents / Q000737:chemistry; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry; D015040:Zirconium
D003188:Composite Resins; D017220:Dentin-Bonding Agents; D005456:Fluorescent Dyes; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; D019279:Resin Cements; D012235:Rhodamines; D012997:Solvents; C420128:Spectrum composite resin; C083568:Z100 composite resin; D014867:Water; D000096:Acetone; D000431:Ethanol; D012822:Silicon Dioxide; C039734:Durafill; C041330:Scotchbond; C044372:Gluma; D015040:Zirconium; D005976:Glutaral