Microshear Bond Strength of Glass Ionomer to Primary Dentin following Surface Treatment by Bur and Er,Cr:YSGG Laser

Background and Aim: Er,Cr:YSGG laser irradiation has been suggested as an effective method of cavity preparation and surface treatment to enhance the bond strength. The aim of this study was to assess the microshear bond strength of Fuji II LC glass ionomer (GI) cement to primary dentin following bur preparation and Er,Cr:YSGG irradiation. Materials and Methods: This in vitro, experimental study was conducted on 20 extracted primary canine teeth. After debris removal, the teeth were sectioned buccolingually and divided into two groups. In group 1, the exposed dentin surface was prepared by fissure bur; while in group 2, the dentin surface was subjected to Er,Cr:YSGG laser irradiation with 2 W power and 80% air and 50% water. Fuji II LC GI cement was applied. After 24 h of storage, the samples were subjected to microshear bond strength test in a microtensile tester. The bond strength values in the two groups were compared using Student t-test. Results: The mean (± standard deviation) microshear bond strength of GI to dentin was 15.36±2.98 MPa in the laser and 4.86±1.36 MPa in the bur group. The mean mi-croshear bond strength in the laser group was significantly higher than that in the bur group (P<0.0001). Conclusion: Irradiation of Er,Cr:YSGG laser with 2 W power increases the microshear bond strength of Fuji II LC GI to primary dentin, and is superior to bur preparation for this purpose.