Thickness effect on optical behavior of monolithic zirconia

TL;DR

This study shows how the thickness of zirconia affects its color and translucency, with 1.0 mm being the most esthetically suitable for dental restorations.

Contribution

The study introduces a comparative analysis of optical properties between monolithic and veneered zirconia at different thicknesses.

Findings

Veneered zirconia showed the highest lightness, while 0.5 mm monolithic zirconia was the darkest.

A 1.0 mm thickness of monolithic zirconia matched veneered zirconia with acceptable color differences.

Increasing thickness reduced translucency, with 1.0 mm being the most esthetically favorable.

Abstract

Achieving optimal esthetics in all-ceramic restorations remains a challenge due to variations in translucency and color influenced by
material thickness. Therefore, this study aimed to evaluate the effect of thickness on the optical properties of monolithic zirconia
compared to veneered zirconia. Fifty zirconia discs were fabricated in varying thicknesses (0.5, 1.0, 1.5, and 2.0 mm) and analyzed for
color and translucency using a spectrophotometer. Veneered zirconia exhibited the highest lightness, while 0.5 mm monolithic zirconia
appeared darkest with clinically unacceptable ΔE values. The 1.0 mm monolithic zirconia showed the closest match to veneered zirconia
with acceptable color differences. Overall, increasing thickness reduced translucency, and a 1.0 mm thickness offered the most
esthetically favorable balance for clinical applications.