The effect of ceramic thickness on opalescence

Abstract

ObjectivesCreating a tooth‐like appearance by use of dental ceramics is still a challenge. Opalescence is a unique property of dental enamel, attempted to be mimicked by dental restorative materials. This study aimed to assess the effect of ceramic thickness on opalescence.Materials and methodsTwenty‐four discs were fabricated of feldspathic ceramic, IPS e.max, zirconia and Enamic ceramics with 10 mm diameter and 0.5 and 1 mm thicknesses (n = 12). The opalescence of ceramic specimens was calculated by measuring the difference in yellow‐blue axis (CIE ∆b*) and red‐green axis (CIE ∆a*) between the transmitted and reflected spectra. One‐way ANOVA was applied to compare the opalescence of different ceramic specimens with variable thicknesses at .05 level of significance.ResultsThe opalescence of feldspathic, IPS e.max, zirconia and Enamic ceramic specimens with 0.5 mm thickness was 1.06 ± 0.15, 3.39 ± 0.15, 1.98 ± 0.15 and 1.44 ± 0.15, respectively. By increasing the thickness to 1 mm, the opalescence of feldspathic, IPS e.max, zirconia and Enamic ceramics changed to 1.12 ± 0.15, 1.47 ± 0.15, 3.85 ± 0.15 and 2.00 ± 0.15, respectively. In all groups except for IPS e.max, the mean opalescence of 1‐mm‐thick specimens was higher than that of 0.5‐mm‐thick specimens.ConclusionType and thickness of ceramic affect its opalescence. The opalescence of all ceramic specimens tested in this study with 0.5 and 1 mm thicknesses was lower than that of the enamel.

Effect of various post-curing light intensities, times, and energy levels on the color of 3D-printed resin crowns

“… 30 In contrast, the thicker enamel on the cusp and marginal surfaces may cause light to be reflected differently, resulting in more-consistent green and yellow colors. 31 The threshold criteria adopted in this study for evaluating color differences were ΔE ≥ 2.6 and ≤ 5.5. These criteria were primarily utilized to assess the magnitude of color variations.…”

Effect of sintering procedures on optical properties, chemical composition, and grain size of monolithic zirconia ceramic at different thicknesses after hydrothermal aging: An in vitro study

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An engineering perspective of ceramics applied in dental reconstructions

“…To report the relationship between layer size and optical properties, Valizadeh, et al . 72 (2020) investigated the effect of ceramic thickness on opalescence parameters. The feldspathic ceramic was compared to lithium disilicate and zirconia 3 rd generation.…”