Er,Cr:YSGG Laser assisted Removal of Ceramic Veneers Cemented with G-Cem Resin Cement:(An in vitro study)

Aims: To evaluate the efficiency of Er,Cr: YSGG laser in debonding of veneers made of lithium disilicate (E-max®) as measured with the shear bond strength(SBS), determine the impact of two laser powers on the SBS required to debond veneers, and finally determining the mode of failure for each group. Materials and methods: Thirty ceramic discs (1mm in thickness and 5mm in diameter) were prepared according to the manufacturer’s instructions. The facial surfaces of enamel for thirty bovine teeth were prepared smooth and the discs cemented onto these prepared surfaces by using GCem™ veneer light cure adhesive cement. Specimens were stored in distilled water for 48hours, after which they were divided randomly into three equal groups (n=10) according to the laser power used as follows: Cont.: Control group that wasn't subjected to laser irradiation; L3: Group irradiated at 3 watt (60 sec.); L5: Group irradiated at 5 watt (60 sec.). SBS was measured by “Instron universal testing machine” and the mode of failure was assessed using stereomicroscope. Results: Both laser irradiated groups showed significant difference in reducing the SBS (p=.000), some of discs debonded during laser irradiation. However, there was no significant difference between the two laser powers used (p=.418). Conclusions: Er, Cr: YSGG could be a safe, effective, fast, and harmless method for reducing SBS of bonded E-max® laminate veneers, without affecting the tooth and the veneer itself. Since there was no significant difference between the two laser powers used, it is advocated to use 3 watts

Resveratrol-Mediated Attenuation of Staphylococcus aureus Enterotoxin B-Induced Acute Liver Injury Is Associated With Regulation of microRNA and Induction of Myeloid-Derived Suppressor Cells

Resveratrol (RES) is a polyphenolic compound found abundantly in plant products including red grapes, peanuts, and mulberries. Because of potent anti-inflammatory properties of RES, we investigated whether RES can protect from Staphylococcal enterotoxin B (SEB)-induced acute liver injury in mice. SEB is a potent super antigen that induces robust inflammation and releases inflammatory cytokines that can be fatal. We observed that SEB caused acute liver injury in mice with increases in enzyme aspartate transaminase (AST) levels, and massive infiltration of immune cells into the liver. Treatment with RES (100 mg/kg body weight) attenuated SEB-induced acute liver injury, as indicated by decreased AST levels and cellular infiltration in the liver. Interestingly, RES treatment increased the number of myeloid derived suppressor cells (MDSCs) in the liver. RES treatment led to alterations in the microRNA (miR) profile in liver mononuclear cells (MNCs) of mice exposed to SEB, and pathway analysis indicated these miRs targeted many inflammatory pathways. Of these, we identified miR-185, which was down-regulated by RES, to specifically target Colony Stimulating Factor (CSF1) using transfection studies. Moreover, the levels of CSF1 were significantly increased in RES-treated SEB mice. Because CSF1 is critical in MDSC induction, our studies suggest that RES may induce MDSCs by down-regulating miR-185 leading to increase the expression of CSF1. The data presented demonstrate for the first time that RES can effectively attenuates SEB-induced acute liver injury and that this may result from its action on miRs and induction of MDSCs