Spectrophotometric examination of the optical effects of monolithic multilayered zirconia with different substrates

The goal of this study is to examine specific optical effects of multilayered and coloured monolithic zirconia considering thickness and substrates of different colours using one of the most advanced spectrophotometers of the world. Multilayered zirconia specimens were used for the study with the thickness range of 0.5–2.5 mm and six types of substrate materials and three types of metal substrates. Measurements were carried out at Budapest Technical University with a PerkinElmer®Lambda1050UV/Vis/NIR spectrophotometer. The substrate colour and the thickness of zirconia affects the optical results, with special regard to colour perceptibility and acceptability. Monochromatic and multilayer zirconia show both similarities and discrepancies in behaviour, i.e. spectral reflectance and ΔE. Owing to the multi-coloured characteristics of multilayered zirconia the optical effect of the substrate less predictable than in the case of monochromatic zirconia thus requiring more detailed planning and implementation.