Surface treatment comparison by application of diamond bur and Er,Cr:YSGG at different powers: morphological and mechanical evaluation

Abstract

This study evaluated the micro-tensile bond strength of new and previous composite resin restorations after surface treatment with diamond bur and Er,Cr:YSGG laser at different power settings (2,3 and 4 W). Micro-hybride composite resin was inserted in metallic mold 5 ×5 ×15 mm and cured for 40 sec according to manufacturer's instruction.12 blocks were made. The bonded surfaces of the 12 blocks so obtained were subsequently ground using Silicon Carbide papers 1200 grit, for 15 seconds under running water. Then the samples randomly were divided into 4 groups: (G1) Bur-treated, (G2) Er,Cr:YSGG laser with power of 2 W and energy of 100 mJ, (G3) Er,Cr:YSGG laser with power of 3 W and energy of 150 mJ, (G4) Er,Cr:YSGG laser with power of 4 W and energy of 200 mJ. One sample of each group was analyzed by SEM while, after cutting the blocks to 1 mm of area samples, the others samples were mechanically tested by Universal testing machine with the speed of 0.5 mm per minute till fracture point. Data were analysed using One-Way ANOVA and Tukey Test. T-test showed no significantly differences between G2 and G4(P=0.064) while G3 demonstrated significant differences than G2 (P=0.001) and G4(P=0.000) and also between samples treated with bur (G1) and G2 (P=0.242) ,G3 (P=0.000) ,G4 (P=0.829); G1 didn't significantly differ to G2 and G4(P>0.05), while G1 and G3(P<0.05). On surface treatment of repaired composite, samples treated by laser at 3W power showed better condition of micro-tensile bond strength.

Effect of Surface Treatment of Two Ceramic Materials by Er,Cr:YSGG Laser Irradiation on The Shear Bond Strength to Resin Cement “A Comparative in-Vitro Study”

“…The Er,Cr:YSGG laser have been introduced into restorative dentistry owing to its capabilities in surface roughness of different dental materials to enhance the bond strength [26,27,[33][34][35], the SEM images of the hybrid resin ceramic showed that acid etching exposed filler particles to form irregular surface with retentive micropores that may improve the mechanical interlocking with resin cement [50] as shown in Figure 6 (A) and in Figure 6 For the failure mode analysis, group RC-C was mainly cohesive failure in the substrate and for groups RC-L1 and RC-L2 showed cohesive, mixed and adhesive failures, denoting stronger micromechanical bond between Vita Enamic and resin cement.…”

“…Regarding CAD/CAM hybrid resin ceramics, studies were published on the impact of different surface treatments of indirect restorations on its bond strength to resin cement [29][30]. Recently, Erbium lasers have been established efficacious on composite resin restorations such as composite inlays, onlays, etc… as surface treatment for enhancing bond strength [31][32][33][34]. On the contrary, the efficacy of Er,Cr:YSGG laser irradiation on hybrid resin ceramics is yet to be proven due to the shortage of related studies [35].…”