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The present work reveals the effect of the addition of commercial MoS 2 (10 wt%) particles on mechanical and two-body abrasive wear behavior of epoxy with/without glass fiber mat reinforcement. The composites were fabricated using casting and simple hand lay-up techniques followed by compression molding. The mechanical properties such as density, hardness, tensile, and flexural properties were determined as per ASTM standards. The abrasive wear testing was carried out using pin-on-disc wear tester for different loads and abrading distances at constant speed of 1 m/s. A significant reduction in wear loss and specific wear rate was noticed after the incorporation of MoS 2 filler allowing less wear of matrix during abrasion which in turn facilitated lower fiber damage. However the incorporation of MoS 2 particles had a detrimental effect on most of the mechanical properties of the composites. The worn surface features were investigated through scanning electron microscopy (SEM) in order to investigate the wear mechanisms.

Aim and Objectives: In dentistry, base metal casting alloys are extensively used for the fabrication of inlays, onlays, crowns, bridges, partial dentures, etc. During the casting of these alloys, excess amount of material used than needed will be collected as sprue buttons at the end, which is either added to the fresh alloy during casting and reused or disposed of. Materials and Methods: The aim of the present in vitro experimental study was to investigate the effect of the complete recasting of four commercially available cobalt-chromium (Co-Cr) and nickel-chromium (Ni-Cr) base metal casting alloys on their cytotoxicity. During the study, four groups of alloys were subjected to complete recasting up to twenty times without the addition of new alloy. The cytotoxicity assessment of the selected alloys after recasting (Co-Cr and Ni-Cr alloys) was carried out using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Results: The results indicated that Co-Cr alloys exhibit superior cell viability compared to Ni-Cr alloys, and cytotoxic potential of the alloys increased with repeated casting and led to increased cell death. The recasting of alloys in the present study did not show high cytotoxicity even after the 20 th recasting. Conclusion: From the results of the present study, it can be concluded that the alloys generated as a waste in the dental laboratory can be safely reused up to five times or at least once before they can be disposed, which reduces the cost of the treatment and also helps in conserving the natural resources.

Aim:The aim of this study was to quantitatively estimate the concentration of ion release from recasted base metal alloys in various pH conditions using atomic absorption spectroscopy (AAS).Materials and Methods:Specimens of commercially available dental casting alloys (cobalt [Co]-chromium [Cr] and nickel [Ni]- chromium [Cr]) were prepared using lost-wax casting techniques and were stored in the test solution for 1 week and 4 weeks, and ions released during chemical corrosion were detected using AAS.Results:An increase in the quantity of ion release was observed with recasting. These changes were higher after twice recasting in Ni-Cr alloy.