Influence of application method on surface free‐energy and bond strength of universal adhesive systems to enamel

Abstract

The aim of the present study was to determine the influence of different adhesive application methods and etching modes on enamel bond effectiveness of universal adhesives using shear bond strength (SBS) testing and surface free-energy (SFE) measurements. The adhesives Scotchbond Universal, All-Bond Universal, Adhese Universal, and G-Premio Bond were used. Prepared bovine enamel specimens were divided into four groups, based on type of adhesive, and subjected to the following surface treatments: (i) total-etch mode with active application; (ii) total-etch mode with inactive application; (iii) self-etch mode with active application; and (iv) self-etch mode with inactive application. Bonded specimens were subjected to SBS testing. The SFE of the enamel surfaces with adhesive was measured after rinsing with acetone and water. The SBS values in total-etch mode were significantly higher than those in self-etch mode. In total-etch mode, significantly lower SBS values were observed with active application compared with inactive application; in contrast, in self-etch mode there were no significant differences in SBS between active and inactive applications. A reduction in total SFE was observed for active application compared with inactive application. The interaction between etching mode and application method was statistically significant, and the application method significantly affected enamel bond strength in total-etch mode.

Comparison of different universal adhesives’ bond strength to laser-assisted bleached enamel

“…17 However in the present study, etch&rinse mode regardless of the used adhesive systems showed better results than self-etch mode in accordance with previous studies. 18,22,30,38,39 Hence the second hypothesis of the present study is accepted. Prior etching ensures a deeper penetration of the selfetch adhesives into the enamel.…”

“…Universal adhesives represent the last generation of adhesives, which can be used with different modes 21,27,28 . Various studies have investigated universal adhesives' enamel bond strength 18,20 . To the best of our knowledge, no study had been performed evaluating the bond strength values to laser-assisted bleached enamel using universal adhesive systems.…”

“…On contrary, in another study no differences in shear bond strength values were obtained between these two adhesive systems. 31 Imai et al 18 determined the effect of different application and etching methods of different universal adhesives on enamel bond strength. Using the same universal adhesives that had been investigated in the present study, they found no difference between the adhesives' bonding values.…”

“…With a single bottle performing two different strategy of bonding, these adhesives are very cost effective. 16 Although many in vitro studies had been conducted to assess the bond strength of universal adhesives [17][18][19][20][21] , to the extent of authors' knowledge no study has examined the effects of pre-restorative Diode Laserassisted bleaching on enamel bond strength of universal adhesives. As bleaching has become a routine treatment in clinics, it is important to find out which application mode would enhance the bonding ability of different universal adhesives to laser-bleached enamel.…”

Surface free energy of enamel treated with sodium hexametaphosphate, calcium and phosphate

“…Among the different methods to determine these parameters, the approach described by Van Oss, Fowkes and Good, and Chaudhury (Neumann et al, 1974;Owens & Wendt, 1969) allows the calculation of the dispersion values, acid-base Lewis parts, polar force and hydrogen bond force, which determine the Lifshitz-van der Waals acid-base equation (Chaudhury, 1996;Good, 1992). Although the acid-base components of surface free energy of some polymeric surfaces, such as polyvinyl chloride (PVC), can exhibit some anomalies when calculated by this method, (Della Volpe & Siboni, 1997), several researchers employed it to estimate the SFE on the surface of enamel (Imai et al, 2017). This method has the same foundation of hydrophobicity angle measurement, despite hydrophobicity is measured only by angles made with water.…”