statement of the problem: increasing the thickness of the veneering porcelain may affect the polymerization of resin cements. incomplete polymerization of resin cements can lead to compromised quality of restoration and decrease the longevity of indirect restorations. purpose: this study sought to assess the effect of ips empress porcelain thickness on the degree of conversion of light-cure and...

despite the great potential of graphene as a nanofiller, achieving homogeneous dispersion remains the key challenge for effectively reinforcing polyolefin (such as polyethylene (pe) and polypropylene (pp)) nanocomposites. therefore, in this research, we report a facile combined in situ polymerization and masterbatch method for fabricating pp/reduced graphene oxide (rgo) nanocomposites. in the p...

The present research work describes an efficient method for facile synthesis of α-MnO2 nanorods by hydrothermal method and preparation of a series of polythiophene/manganese dioxide (PTh/MnO2) nanocomposites with various α-MnO2 ratios. These nanocomposites were fabricated by in-situ oxidative polymerization method using FeCl3 as oxidant, and characterized by Fourier transformed infrared (FT-IR)...

styrene nanocomposites were synthesized by in-situ atom transfer radical polymerization at 110oc. the variations of monomer conversion and the linearity of semilogarithmic kinetic plot, some signs of living polymerizationand constant radical concentration in the reaction medium, were revealed by gas chromatography technique (gc). according to the gel permeation chromatography (gpc) results, the...

This study evaluated the effects of the light curing methods and resin composite composition on composite polymerization contraction behavior and resin composite adaptation to the cavity wall using μCT-3D visualization analysis and dye penetration test. Cylindrical cavities were restored using Clearfil tri-S Bond ND Quick adhesive and filled with Clearfil AP-X or Clearfil Photo Bright composite...

Most of the composites and sealants used in dentistry are based on bisphenol A diglycidylether methacrylate (Bis-GMA). Reports revealed that in situ polymerization is not complete and that free monomers can be detected by different analytic methods. Concerns about the estrogenicity of bisphenol A (BPA) and other aromatic components leached from commercial products have been expressed. We studie...