Shielding Effect of Experimentally Produced Opaque Resin

Abstract

The aim of this study was to develop an opeque resin that has a color shielding ability against colored dentin and does not influence the color of titanium dioxide was considered to increase the color shielding ability, and three types of materials -rutile, anatase, and apatite coating- were examined. The apatite coating was chosen as the opaquer to be mixed with low viscosity resin composite, because this type of material has the least influence on composite polymerization. Samples of opaque resin disks with mixing ratios of 0.50, 1.00, 2.00, 3.00 and 4.00%, and thicknesses of 0.25 and 0.50 mm were prepared. The color shielding ability and color differences were calculated from each color of coronal composite and the color that appeared from the composite which was laid on the experimental opaque resin to shield the colored dentin based on L*a*b* values with a colorimeter. As a result, a 0.50-mm-thick opaque resin disk mixed with apatite coating with a mixing ratio of 2.00% exhibited a good shielding effect and a lower influence on the color of the coronal composite.