Effect of pretreatment on Er:YAG laser-irradiated dentin

Abstract

Erbium:yttrium-aluminum-garnet (Er:YAG) laser preparation of tooth cavities for restoration is an increasingly popular method, but its compatibility with existing composite material bonding protocols has not been fully defined. This study evaluated the effect of laser and etchant pretreatments on the performance of one-bottle self-etch adhesives in Er:YAG laser-prepared dentin. Eight groups of 20 extracted teeth were established to investigate bonding in tested dentin disks. Various combinations of laser preparation (with/without), pretreatment (none/acid-etch/low-fluence Er:YAG irradiation), and self-etching adhesive (G-Bond Plus or Xeno V) were tested. Samples were then restored with composite resin and subjected to a tensile bond strength (TBS) test. We also performed scanning electron microscopy (SEM) on dentin disks from some of these groups before and after adhesive application to evaluate their microscopic morphological appearance. Statistical analysis (Dunnett T3 test coupled with the general linear model at 5% significance level) revealed that the laser preparation of dentin did not impact on TBS (p = 0.914), whereas pretreatment with either phosphoric acid (p < 0.0001) or low-fluence Er:YAG laser irradiation (p < 0.0001) significantly increased TBS, although there was no difference between them in their respective elevation of TBS. SEM analysis demonstrated that both acid and laser pretreatments reduced irregularities and produced a more homogeneous surface. Er:YAG laser preparation does not compromise the efficacy of one-step self-etch dentin adhesives, and pretreatment with phosphoric acid or low-fluence Er:YAG laser can significantly increase the TBS of adhesion to this irradiated dentin.

Shear bond strength of pit and fissure sealants on permanent teeth after several etching protocols: In vitro study

“…9 Additionally, Chen et al reported that Er:YAG laser conditioning may not compromise self-etching adhesives efficacy when employed for dentin conditioning. 30 Based on the evaluation of all outcome parameters defined in this in vitro study, the etching protocols could be grouped into 4 categories according to SBS values and statistical analysis. Optimal adhesion includes phosphoric acid and phosphoric acid + Er:YAG laser groups, followed by appropriate adhesion for self-etching group, sufficient adhesion for Er:YAG laser and Er:YAG laser + phosphoric acid groups.…”

Laser Application for Restorative Dentistry

“…SEM and TBS analysis from Chen et al demonstrated that both low-level laser energy pretreatment and acid etching reduced irregularities and produced a more homogeneous surface, signifi cantly increasing the tensile bond strength of adhesion to the irradiated dentin [ 43 ].…”

Lasers in Restorative Dentistry

“…A study by showed that the Er, Cr:YSGG radiation at a low pulse energy of 3.13 mJ, delivered at an incidence angle of 5° to the dentin slice surface, resulted in signifi cant bacterial reduction up to a dentin thickness of 500 μm [ 101 ].…”