Mechanical stability of adhesives under water storage.
OBJECTIVE
To evaluate the effects of storage condition (wet or dry) and storage time (24h and 3 months) on the ultimate tensile strength (UTS) of Single Bond (SB), 3M-ESPE; Opti Bond Solo Plus (OB), Kerr; One Step (OS), Bisco, and Prime & Bond NT (PB), Dentsply adhesive resins.


METHODS
Hourglass-shaped specimens were obtained from a metallic matrix. Each adhesive was dispensed to fill the molds completely and left undisturbed in a dark chamber for 4 min at 37 degrees C for solvent evaporation. They were individually light-cured for 80s at 500 mW/cm(2) and randomly divided into three groups: 24h of water storage; 3 months of water storage; 3 months of dry storage. The specimens were tested in tension at 0.5 mm/min using the microtensile method and data were analyzed by two-way ANOVA and SNK tests for each material.


RESULTS
Water storage for 3 months did not cause significant changes in the UTS of any of the adhesives (p-value). Values for water storage ranged from 25.9 MPa for Single Bond at 24h to 32.7 MPa for Prime & Bond NT after 3 months. Dry storage for 3 months yielded significantly higher UTS for most adhesives, which ranged from approximately 20% for Opti Bond to 160% higher values for Single Bond compared to their 3 months wet storage values.


CONCLUSIONS
The effects of storage condition and time on the UTS of adhesives were material-dependent.
Manso
Adriana P
AP
Department of Operative Dentistry, College of Dentistry, University of Florida, Gainesville, FL 32610-0415, USA. amanso@dental.ufl.edu
Bedran-Russo
Ana K
AK
Suh
Byoung
B
Pashley
David H
DH
Carvalho
Ricardo M
RM
D000096:Acetone; D000388:Air; D001840:Dental Bonding; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004356:Drug Storage; D000431:Ethanol; D008422:Materials Testing; D011897:Random Allocation; D019279:Resin Cements / Q000737:chemistry; D012997:Solvents; D013314:Stress, Mechanical; D013718:Tensile Strength; D013997:Time Factors; D014867:Water
D017220:Dentin-Bonding Agents; D019279:Resin Cements; D012997:Solvents; D014867:Water; D000096:Acetone; D000431:Ethanol