Adhesive Temperature: Effects on Adhesive Properties and Resin-Dentin Bond Strength

Abstract

AD Loguercio D Salvalaggio AE Piva CA Klein-Jú nior M de LR Accorinte MM Meier RHM Grande A Reis Clinical RelevancePreheating ethanol/water-based adhesive systems could be useful to improve the hybrid layer quality. SUMMARYObjectives: To evaluate the effect of adhesive temperature on the resin-dentin bond strength (lTBS), nanoleakage (NL), adhesive layer thickness (AL), and degree of conversion (DC) of ethanol/water-(SB) and acetone-based (PB) etch-and-rinse adhesive systems.Methods: The bottles of the two adhesives were kept at each temperature (58C, 208C, 378C, and 508C) for 2 hours before application to demineralized dentin surfaces of 40 molars. Specimens were prepared for lTBS testing. Bonded sticks (0.8 mm 2 ) were tested under tension (0.5 mm/min). Three bonded sticks from each tooth were immersed in silver nitrate and analyzed by scanning electron microscopy. The DC of the adhesives was evaluated by Fourier transformed infrared spectroscopy.Results: Lower lTBS was observed for PB at 508C. For SB, the lTBS values were similar for all temperatures. DC was higher at 508C for PB. Higher NL and thicker AL were observed for both adhesives in the 58C and 208C groups

Adhesives Doped with Bioactive Niobophosphate Micro-Filler: Degree of Conversion and Microtensile Bond Strength

“…In this study, the DC values found for the two control groups (PB and OS) were in agreement with values in the literature (21,23). Leitune et al (2) found no difference in the DC when incorporating Nb 2 O micro-filler into an experimental adhesive system.…”

“…The dentin surface was etched with 37% H 3 PO 4 (15 s), rinsed for 15 s, and kept the dentin slightly moist, so that all adhesives were applied on the moist substrate (21); two layers of the adhesive system were applied, and soft air jets were blown on the samples for 10 s, followed by polymerization (Optilux 501, Kerr, Orange, CA, USA) at 600 mW/cm² for 20 s. Table 1 shows the application mode, composition, manufacturer and lot number of the used materials. After the adhesive procedure, a 6.0 mm high composite resin restoration (Lis, FGM, Joinville, SC, Brazil) was performed in three 2-mm increments of and light polymerized for 40 s.…”

In Vitro Effect of Temperature on Dentin Bond Strength of Universal Adhesive Systems

“…Some studies have shown that temperature has an effect on the properties and bond strength of the adhesives, (13)(14)(15) whereas other studies have reported that the temperature of the adhesive before it is used does not significantly affect the bond strength (16) In the former studies, the lowest SBS values were reported in restorations made with adhesives used immediately they were removed from a refrigerator (at 4°C). The viscosity of an adhesive is high at low temperatures, and its increase prevents proper wetting of the substrate due to a low spreading velocity of the adhesive (17) Another reported consequence of refrigerating polymer-based materials is that it may reduce the vapor pressure of the solvents present, thus inhibiting their evaporation from the adhesive layer (18).…”

Dentin pretreatment and adhesive temperature as affecting factors on bond strength of a universal adhesive system

“…Thus, the solvents and the water present in the adhesive should ideally be removed to a sufficient degree because residual solvents can inhibit the polymerization and negatively affect the mechanical properties of the adhesive 16 , 26 . Hence, a clinical approach to improve the adhesive properties indicates the use of warm air 9 , 13 , 16 , 19 , 20 , 26 to facilitate the evaporation of the solvent as well as the use of preheated adhesive systems 11 , 18 , 25 , 28 in order to increase the speed of permeation of the monomers and the evaporation of the residual monomeric content. The quality and the stability of the hybrid layer can be influenced by the heating of adhesive through the stimulation of their chemical reactions and, thus, some properties of the monomeric solutions, such as degree of monomer conversion and viscosity, can be changed by temperature 1 , 11 , 18 , 23 , 28 .…”

“…Hence, a clinical approach to improve the adhesive properties indicates the use of warm air 9 , 13 , 16 , 19 , 20 , 26 to facilitate the evaporation of the solvent as well as the use of preheated adhesive systems 11 , 18 , 25 , 28 in order to increase the speed of permeation of the monomers and the evaporation of the residual monomeric content. The quality and the stability of the hybrid layer can be influenced by the heating of adhesive through the stimulation of their chemical reactions and, thus, some properties of the monomeric solutions, such as degree of monomer conversion and viscosity, can be changed by temperature 1 , 11 , 18 , 23 , 28 . Temperature can increase the mobility of free radicals, benefiting the polymerization of the adhesive by increasing the degree of conversion 1 , besides decreasing the viscosity and improving the speed of spreading of the adhesive and deeper penetration into dentin 11 , 18 , 25 , 28 .…”