Effect of Laser Conditioning on Shear Bond Strength and Durability of Universal Adhesive to Dentin: An In Vitro Study

Erbium, Chromium-doped Yttrium Scandium Gallium Garnet (Er, Cr:YSGG) lasers have garnered increasing attention. 6Several studies [7][8][9][10] have suggested that laser conditioning may enhance the quality of the dentin surface prior to bonding.These lasers can selectively ablate mineralized tissue, effectively remove the smear layer, and expose dentinal tubules, all without inducing thermal damage to the underlying substrate. 11,12rbium-family lasers are capable of selectively ablating the mineralized tissues by targeting water and hydroxyapatite IntroductIonComposite resin restorations remain a cornerstone in modern restorative dentistry, not only for their esthetic appeal but also for their minimally invasive approach.Nevertheless, their success hinges on establishing a long-lasting bond with the underlying tooth structure, particularly dentin. 1 Unlike enamel, dentin poses several bonding challenges due to its heterogeneous structural nature, intrinsic moisture, and the presence of dentinal tubules containing fluid, all of which can impede optimal adhesive penetration. 2dhesive systems are traditionally classified into etch-andrinse and self-etch adhesives.Universal adhesives have been developed to simplify bonding procedures by offering versatility in application-functioning in either self-etch or etch-and-rinse modes.Their simplified protocol reduces technique sensitivity, minimizes operator error, and improves clinical efficiency. 3,4lthough self-etch adhesives offer advantages such as decreased postoperative sensitivity and fewer procedural steps, concerns persist regarding their long-term bonding performance to dentin.These systems often struggle with effective smear layer penetration, and their bond durability can be compromised over time due to factors such as hydrolytic degradation, nanoleakage, and incomplete resin infiltration into the hybrid layer. 3,5o address these limitations, erbium-based laser technologiesspecifically Erbium-doped Yttrium Aluminum Garnet (Er:YAG) and