Repeatability in Color Measurements of a Spectrophotometer using Different Positioning Devices

Area of Science:

• Dental Materials Science
• Colorimetry
• Optical Measurement

Background:

• Accurate dental shade matching is crucial for aesthetic restorations.
• Intraoral spectrophotometers offer objective color measurement but their repeatability can be influenced by methodology.
• Evaluating different measurement techniques is essential to optimize clinical use.

Purpose of the Study:

• To assess the repeatability of color measurements using an intraoral spectrophotometer.
• To compare three different measurement methods: custom tray (CT), custom jig (CJ), and free hand (FH).
• To evaluate the influence of two operators on measurement repeatability.

Main Methods:

• Sixty human and artificial teeth were measured twice by two operators using the Vita EasyShade spectrophotometer.
• Measurements were performed using the CT, CJ, and FH methods.
• Statistical analysis included Friedman and Wilcoxon signed-rank tests, and paired-sample t-tests.

Main Results:

• Repeatability varied among the three methods and between operators.
• Operator A showed no significant difference between FH and CT, but FH differed from CJ.
• Operator B showed a significant difference between FH and CT, but not between FH and CJ or CT and CJ.

Conclusions:

• The repeatability of intraoral spectrophotometer color measurements differs based on the method used.
• The custom tray (CT) method generally performed well for both operators, suggesting improved reliability.
• Utilizing a custom tray with apertures can enhance the consistency of spectrophotometric color assessments in dentistry.