Effect of glycerin on the optical proprieties of PEEK

Abstract

The aim of this study is to evaluate the optical proprieties of PEEK and the influence of a coupling medium (G-glycerin), by testing the hypothesis that glycerin can influence translucency. Eight standardized specimens were fabricated from CopraPeek (WhitePeaks Dental Solution, Germany) Medium A2 dentine 10 mm x 15 mm polished to 1.0 in thickness and Nexco Paste Dentine veneer material shade A3, with thicknesses of 0.5, 1.0 and 1.5 mm. Color and CIELAB coordinates were evaluated using Vita 0.5, 1.0 and 1.5 mm. Color and CIELAB coordinates were evaluated using Vita Easyshade. All evaluations were repeated using glycerin and the values were recorded. Translucency is the relative amount of light that passes through a unit thickness of a material. Translucency parameter (TP) and contrast ratio (CR) were calculated. Also the value of color change (∆E*) was calculated and statistical analysis was performed [1]. Expected results: The mean TP values of the studied samples were in the range of 1.22-3.81, which is lower than those reported for natural teeth [2][3][4]. The OP values of PEEK were recorded in the range of 0.78–3.11, also lower than those of natural teeth. Although mean translucency values were significantly different for each method (TP and CR), they were highly correlated (r2=0.70), even when G was used (r2=0.56). Conclusion: The coupling medium significantly influenced the mean values of ∆E and translucency. Clinical assessment of perceptibility and acceptability thresholds of translucency is needed