Evaluating the effect of ER,CR.YSGG LASER and conventional acid etching on shear bond strength of composite on enamel of primary teeth (in vitro study)

Abstract Objective: The aim of this study is to compare the shear bond strength of composite resin bonded to enamel of primary teeth after etching using Erbium chromium –YSGG laser and conventional phosphoric acid. Study design:Experimental in vitro study. Materials and Methods: A total of thirty extracted or exfoliated primary teeth were divided into three groups according to the type of etching techniques. Group I Er,Cr:YSGG Laser etching with power set at 1W, Group II Er,Cr:YSGG laser with power set at 1.5W and group III acid etching using phosphoric acid. Evaluation: The 30 specimens were assigned for shear bond strength (SBS) evaluation test using a universal testing machine. Mode of failure was evaluated using stereomicroscope and only six specimens were evaluated qualitatively to asses enamel surface topography using scanning electron microscopy. Results: Shear bond strength of acid etching group showed the highest followed by 1.5W laser-etching group, while 1W laser etching group demonstrated the least mean shear bond strength. The acid etched enamel was statistically significantly higher (P < <0.0001) than that other groups. Conclusions: The mean SBS of composite with acid etching is significantly higher in comparison to Er, Cr: YSGG (operated at 1W & 1.5W for 10 s) laser‑etched enamel.