Visual and instrumental shade matching using CIELAB and CIEDE2000 color difference formulas

Area of Science:

• Dental Materials Science
• Color Science in Dentistry
• Visual Perception Studies

Background:

• Accurate dental shade matching is crucial for aesthetic restorations.
• Visual shade matching is subjective and can be influenced by lighting conditions and observer fatigue.
• Instrumental methods offer objective color measurement but require validation against human perception.

Purpose of the Study:

• To compare the performance of visual and instrumental shade matching.
• To evaluate two shade guides (Vita Classical and Vita Toothguide 3D-Master) and three color difference formulas.
• To determine which combination best represents dental students' visual perception of tooth color.

Main Methods:

• Spectroradiometer (SP) and Easyshade Advance (EA) were used to measure tooth and shade tab colors.
• Dental students (DS) performed visual shade matching using Vita Classical (VC) and 3D guides.
• Color differences were calculated using CIELAB, CIEDE2000(1:1:1), and CIEDE2000(2:1:1) formulas.

Main Results:

• Spectroradiometer (SP) showed higher agreement (25-75%) with visual matching than Easyshade Advance (EA) (0-25%).
• Vita Classical (VC) shade guide yielded more consistent visual assessment results (23-55%) compared to 3D (19-34%).
• The CIEDE2000(2:1:1) formula, using SP and VC, best estimated visual perception.

Conclusions:

• The combination of spectroradiometer (SP), CIEDE2000(2:1:1) formula, and Vita Classical shade guide closely matched dental students' visual perception.
• Instrumental shade determination should complement, not replace, experienced human visual assessment for optimal results.