A new method for matching tooth colors with color standards

Area of Science:

• Dental materials science
• Colorimetry
• Optical physics

Background:

• Accurate tooth color determination is crucial in restorative and cosmetic dentistry.
• Current visual shade matching methods are subjective and lack reproducibility.
• Objective color measurement systems are needed to standardize clinical assessments.

Purpose of the Study:

• To introduce and evaluate a new quantitative method for intra-oral tooth color determination.
• To compare the reproducibility and clinical relevance of two distinct measurement configurations (Method 1 and Method 2).
• To assess the suitability of the developed method for clinical applications in dentistry.

Main Methods:

• Developed a quantitative intra-oral tooth color determination system using opaque color standards.
• Analyzed color standards spectrophotometrically to compute C.I.E. color coordinates.
• Investigated two illumination/observation setups: Method 1 (large window illumination, small window collection) and Method 2 (small window for both).

Main Results:

• Both methods quantified tooth color into three dimensions.
• Method 1 exhibited high inter-examiner consistency (n=25) for ten teeth.
• Method 2 showed low inter-examiner agreement and selected standards often disagreed with clinical expectations.
• Differences were attributed to the optical properties of dental enamel, such as volume reflection.

Conclusions:

• Method 1 provides reproducible quantification of clinical tooth discoloration based on C.I.E. color specifications.
• Method 1's results align better with clinical expectations compared to Method 2.
• The developed Method 1 shows potential for application in prosthetic dentistry for accurate shade selection.