Effects of light curing modes and ethanol-wet bonding on dentin bonding properties

Abstract

Abstract:Objective: This study explored the effects of different light curing modes and ethanol-wet bonding on dentin bonding strength and durability. Methods: A total of 54 molars were randomly divided into three groups: Single Bond 2, Gluma Comfort Bond, and N-Bond. Based on the three light-curing modes and presence or absence of ethanol pretreatment, the samples were assigned to six subgroups: high-light mode, ethanol pretreatment+high-light mode, soft-start mode, ethanol pretreatment+soft-start mode, standard mode, and ethanol pretreatment+standard mode. All samples were bonded with resin based on the experimental groups. After 24 h and 6 months of water storage, a universal testing machine was used to measure microtensile bond strength. Scanning electron microscopy (SEM) was applied to observe mixed layer morphology. Results: The 24-h and 6-month microtensile bond strengths of the ethanol pretreatment groups were significantly higher than those of the non-ethanol pretreatment groups at the same light modes (P<0.05). With or without ethanol pretreatment, the microtensile bond strengths of the high-light modes were significantly lower than those of the soft-start modes and standard modes (P<0.05). The microtensile bond strengths of samples from the 6-month water storage group significantly decreased compared with those of samples from the 24-h water storage group (P<0.05). The soft-start groups and standard groups formed better mixed layers than the high-light mode groups, whereas the ethanol pretreatment groups formed more uniform mixed layers than those without ethanol pretreatment. Conclusions: Ethanol-wet bonding technique, soft-start, and standard modes could improve dentin bonding properties.

Bond strength to microtraction and nanofiltration using ethanol wet bonding technique in fresh extracted teeth: An ex vivo study

“…Meanwhile, Li et al . [ 5 ] evaluated contemporary adhesive systems (mixture of monomers, hydrophobic, and hydrophilic) under the protocol of wet adhesion with ethanol with simplified dehydration (1 min, waste water from the wash) protocol in vitro . Compared to wet adhesion with water, the ethanol wash groups produced similar or higher values of μ-tensile bond strength (μTBS) at 24h, because contemporary adhesive systems with monomer mixtures are more tolerant to the residual presence of water when used within an ethanol wash protocol with simplified dehydration.…”

“…Due to the better compatibility of hydrophilic monomers with ethanol, it is sought to determine whether the adhesive stability of contemporary systems can be improved if used with an ethanol wash protocol. [ 21 22 23 24 ] However, this study is important because the results can further optimize the performance of dental restorations with the adhesive systems currently used by dental professionals.…”

“…Consequently, manufacturers have developed dentin adhesives that are compatible with humid environments. [ 5 ]…”

“…On the other hand, it has been determined that the hydrophobic components of the adhesives have good miscibility with ethanol, and the so-called hydrophilic monomers also show better solubility in ethanol than in water. [ 5 ] This is because ethanol is an ideal solvent for most hydrophobic monomers; the wet ethanol adhesive technique has been proposed to be applied with hydrophobic adhesives to improve its infiltration and reduce the degradation of the adhesive interface. [ 1 ] The reasoning behind this adhesion technique is that dehydration with ethanol converts etched hydrophilic dentin, allowing the use of relatively hydrophobic monomers to infiltrate the collagen matrix.…”

EVALUATION OF THERMOCYCLING EFFECT ON SHEAR BOND STERNGTH OF ORTHODONTIC MOLAR TUBE BONDED WITH TWO DIFFERENT ADHESIVE SYSTEMS (Electron microscopic study)

“…Orthodontic accessories are subjected to high masticatory forces in the molar region which being up to 53kg (5) . The bonding resistance of orthodontic tubes depend on multiple factors, such as, type of manufacturing material (6) , the design (7) , method of polymerization of the adhesive (8) , applied adhesive system (9) and contamination of saliva or blood during the process of bonding (10) . Although the acid etching composite technique has been frequently used in orthodontics, it still has a number of drawbacks such as enamel loss after acid etching (11) , possible fractures of enamel during the debonding process and enamel damage after debonding due to cleanup procedures (12) .…”