Micro-shear bond strength of resin cements to Er,Cr:YSGG laser and/or acid etched enamel

Abstract

The purpose of this study was to evaluate the effect of Er,Cr:YSGG laser irradiation and/ or acid etching on the micro-shear bond strength (µSBS) of two different dual-cured resin cements to human enamel. 24 intact, extracted molars were sectioned longitudinally and randomly divided into three subgroups according to three surface pretreatment methods:(1) Er,Cr:YSGG laser (Waterlase MD, Biolase) irradiation was used with a power setting of 2 W (55% water and 65% air), and a repetition rate of 20 Hz for 10 s; (2) 37% phosphoric acid application for 20 s;(3) Re-etching with phosphoric acid for 20 s after the Er,Cr:YSGG laser irradiation as in group1.12 enamel discs for each of the resin cements (Panavia F2.0 and Variolink N) were prepared and three cylinders of resin cements were bonded to each enamel surface (n = 12). A microshear bond test (EZ-test-500 N) was used at a cross-head speed of 1 mm min −1 to determine the µSBS. One-way analysis of the variance and Tukey post-hoc tests at the 95% confidence level were used to analyze the µSBS values. Panavia F2.0 verified significantly higher µSBS values than Variolink N (p < 0.05) for all the tested surface pretreatment methods. The combination of laser and acid etching on enamel produced higher µSBS values for bonding both resin cements than the use of acid or laser irradiation alone. The combination of the Er,Cr:YSGG laser and phosphoric acid etching of the enamel for the cementation of indirect restorations with Variolink N and Panavia F2.0 produced better µSBS values to enamel than the use of phosphoric acid or Er,Cr:YSGG laser etching alone, holding the potential to become a highly attractive method for routine use.

Evaluation of Chlorhexidine Application on Shear Bond Strength in Different Brackets and Different Etching Techniques in Vitro Study

“…So, the SBSvalues for LM and LC groups in present study are still acceptable clinically strengths for bracket bonding. These results agree with the fi ndings to (8,10,16) . But is different from Findings ( 17,9) .…”

“…In present study, the laser parameters determine based on a previous studies and pilot study (8)(9) (10) The results of present study revealed that SBS values of brackets bonded with laser etching were signifi cantly lesser than that of acid etching in both(LM,LC brackets ). Reynolds 29 recommended the SBS ranged from 6 to 8 MPa clinically acceptable bonding.…”

“…The power of laser output can be various from 0-6W determined the tissue to be cut. The power settings for laser groups had been selected on the basis dentinal studies and pilot study, the using 2 W power, the rate repetition pulse 20 pulses / second (20 Hz), a duration of the pulse 140microseconds, (8,9,10) . The Er,Cr:YSGG laser (Waterlase, I plus from Biolase USA ), is produces accurate cuts for hard tissue via interaction with water at the enamel surface.…”

Micro Shear Bond Strength of Resin Composite Restorations to Er,Cr: YSGG Laser Treated Enamel Versus Conventional Acid Etching ( An In Vitro Study)

“…The combination of both acid and laser etchingin factwas found to increase the etching depth and causing an eventual greater penetration of acid. 16,25,26 This study's findings; however, were in contradiction with various studies that do not recommend the use of Er,Cr: YSGG laser etching such as the studies conducted by Ustunkul et al (2016) 27 , Shafiei et al (2018) 28 and Al Habdan et al (2021). 17 The results obtained by Ustunkul et al (2013) can be interpreted by the fact that the study utilized a silorane system adhesive which relies on a cationic polymerization reaction that is completely different from the adhesive system used in this study which relies on free radical polymerization.…”

“…This causes their rapid evaporation and creates micro-explosions of the tooth particles during tissue ablation resulting in microscopic and macroscopic roughness. 25 This in combination with the effect of conventional acid etching is responsible for yielding the statistically significant increase in SBS values. This could also be further interpreted by the occurrence of a melting and recrystallization process that creates a porous surface similar to the type III pattern produced by phosphoric acid etching.…”