Effects of adhesive temperature on the early and 6-month dentin bonding.
OBJECTIVE
The aim of this study was to test the effect of adhesive temperature on the bond strength to dentin (muTBS) and silver nitrate uptake (SNU) of an ethanol/water (Adper Single Bond 2 [SB]) and an acetone-based (Prime&Bond 2.1 [PB]) etch-and-rinse adhesive system.


METHODS
The bottles of each adhesive were kept in various temperatures (5 degrees C, 20 degrees C, 37 degrees C and 50 degrees C) for 1h previously to its application in the occlusal demineralized dentin of 40 molars. Bonded sticks (0.8 mm(2)) were tested in tension (0.5 mm/min) immediately (IM) or after 6 months (6 M) of water storage. Two bonded sticks from each hemi-tooth were immersed in silver nitrate and analyzed by SEM. Data were analyzed by two-way repeated measures ANOVA and Tukey's test (alpha=0.05).


RESULTS
No significant difference in muTBS was detected for both adhesives at 5 degrees C and 20 degrees C. The highest bond strength for PB was observed in the 37 degrees C group while for SB it was in the 50 degrees C. Significant reductions of bond strengths were observed for PB at 37 degrees C and SB at 50 degrees C after 6 M of water storage. Silver nitrate deposition was seen in all hybrid layers, irrespective of the group. Lower silver nitrate deposition (water trees) in the adhesive layer was seen for PB and SB at higher temperatures.


CONCLUSIONS
The heating or refrigeration of the adhesives did not improve their resin-dentin bond resistance to water degradation over time.
Reis
Alessandra
A
School of Dentistry, Department of Restorative Dentistry, University Estadual de Ponta Grossa, Ponta Grossa, PR, Brazil. reis_ale@hotmail.com
Klein-Júnior
Celso Afonso
CA
Accorinte
Maria de Lourdes Rodrigues
Mde L
Grande
Rosa Helena Miranda
RH
dos Santos
Celso Bilynkievycz
CB
Loguercio
Alessandro D
AD
D000096:Acetone / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D001840:Dental Bonding; D003799:Dental Stress Analysis; D003804:Dentin; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents / Q000737:chemistry; D000431:Ethanol; D006801:Humans; D006868:Hydrolysis; D008422:Materials Testing; D008964:Molar, Third; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012835:Silver Nitrate / Q000032:analysis; D012997:Solvents; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors
D017220:Dentin-Bonding Agents; D011109:Polymethacrylic Acids; D019279:Resin Cements; D012997:Solvents; C444444:prime and bond 2.1; C115612:single bond; D000096:Acetone; D000431:Ethanol; D017438:Bisphenol A-Glycidyl Methacrylate; D012835:Silver Nitrate