IADR Abstract Archives
Effects of dimethyl sulfoxide (DMSO) on the durability of resin- dentin bond strength and hybrid layer quality.
Objectives: The objective of this study was to evaluate the microtensile bond strength (µTBS) and nanoleakage (NL) of bonded resin-dentin interfaces pretreated with various concentrations of dimethyl sulfoxide (DMSO).
Methods: Extracted sound human third molars were used in this study. Occlusal enamel was removed under water cooling and teeth were ground with 600-grit SiC to expose superficial dentin. Dentin surfaces were acid-etched with 37% phosphoric acid and pretreated with various concentrations of DMSO (0.001, 0.01, 0.1, 1, 5, 10, 20%) for 30 s before adhesive application. A single-bottle etch-and-rinse adhesive (SingleBond, 3M ESPE) was applied and restored with resin composite (FILTEK Supreme XTE, 3M ESPE) incrementally to a height of 5mm. Twenty four hours after bonding, restored teeth were sectioned to obtain 0.9x0.9 mm beams and were stored in artificial saliva at 37°C for either 24 h or 6 months before µTBS evaluation (n=6 teeth/group). The microtensile bond strength testing (µTBS) was carried out at a crosshead speed of 0.5mm/min. Six beams per tooth were submitted to qualitative nanoleakage evaluation using SEM. The data were analyzed using ANOVA and Tukey’s test (α=0.05).
Results: The pretreatment with DMSO had no significant effect on 24 hrs bond strength or nanoleakage. After 6 months storage, μTBS of control group decreased significantly, and also low DMSOconcentrations used (0.001, 0.01%). Whereas 5% and 0.1% DMSO treated groups showed an increase in bond strength. Also DMSO treated groups showed lower nanoleakage compared to control and 0.001% DMSO.
Conclusions: The use of higher concentrations of DMSO as dentin pretreatment improves the durability of dentin bonding. The use of DMSO as a primer is promising to prolong integrity of resin-dentin interface.
Methods: Extracted sound human third molars were used in this study. Occlusal enamel was removed under water cooling and teeth were ground with 600-grit SiC to expose superficial dentin. Dentin surfaces were acid-etched with 37% phosphoric acid and pretreated with various concentrations of DMSO (0.001, 0.01, 0.1, 1, 5, 10, 20%) for 30 s before adhesive application. A single-bottle etch-and-rinse adhesive (SingleBond, 3M ESPE) was applied and restored with resin composite (FILTEK Supreme XTE, 3M ESPE) incrementally to a height of 5mm. Twenty four hours after bonding, restored teeth were sectioned to obtain 0.9x0.9 mm beams and were stored in artificial saliva at 37°C for either 24 h or 6 months before µTBS evaluation (n=6 teeth/group). The microtensile bond strength testing (µTBS) was carried out at a crosshead speed of 0.5mm/min. Six beams per tooth were submitted to qualitative nanoleakage evaluation using SEM. The data were analyzed using ANOVA and Tukey’s test (α=0.05).
Results: The pretreatment with DMSO had no significant effect on 24 hrs bond strength or nanoleakage. After 6 months storage, μTBS of control group decreased significantly, and also low DMSOconcentrations used (0.001, 0.01%). Whereas 5% and 0.1% DMSO treated groups showed an increase in bond strength. Also DMSO treated groups showed lower nanoleakage compared to control and 0.001% DMSO.
Conclusions: The use of higher concentrations of DMSO as dentin pretreatment improves the durability of dentin bonding. The use of DMSO as a primer is promising to prolong integrity of resin-dentin interface.