IADR Abstract Archives
In Vitro Tooth Colour Measurement Using a Non-contact Imaging Method
Objectives: To evaluate the applicability of a non-contact imaging system (DigiEye system, Verivide) for tooth colour measurements in vitro.
Methods: A set of sound Bovine enamel blocks (n=8) were prepared (6mm x 6mm).The samples were placed in sterile saliva for 2 hours. After rinsing with water, baseline tooth colour was measured using a calibrated DigiEye system, which consists of a digital camera and diffuse D65 lighting. Baseline CIELAB and tooth whiteness index (WIO) values were obtained. The specimens were then treated with water for 1 hour, rinsed and their colour remeasured. The protocol was repeated with a 1 hour water treatment and colour measurement. The mean colour values were determined and the colour differences from baseline (ΔΕ*ab) were calculated for each time point.
Results: The mean (S.E.) of the colour and whiteness values and the colour differences ΔΕ*ab are shown in table below.
The mean colour differences (ΔΕ*ab) were much less than 1 at both time points. According to dental colour matching this difference would be considered not perceivable by eye. A variance components analysis (JMP 11) was used to determine how much of the variability in the data was due to measurement variation i.e. the repeatability of measurements made on the same day. The analysis showed that 1.1, 1.0, 0.1 and 0.2% of the variability was due to measurement variation for L, a, b and WIO respectively.
Conclusions: The results indicate that the DigiEye system is applicable for repeatable tooth colour and whiteness measurements in vitro.
Methods: A set of sound Bovine enamel blocks (n=8) were prepared (6mm x 6mm).The samples were placed in sterile saliva for 2 hours. After rinsing with water, baseline tooth colour was measured using a calibrated DigiEye system, which consists of a digital camera and diffuse D65 lighting. Baseline CIELAB and tooth whiteness index (WIO) values were obtained. The specimens were then treated with water for 1 hour, rinsed and their colour remeasured. The protocol was repeated with a 1 hour water treatment and colour measurement. The mean colour values were determined and the colour differences from baseline (ΔΕ*ab) were calculated for each time point.
Results: The mean (S.E.) of the colour and whiteness values and the colour differences ΔΕ*ab are shown in table below.
The mean colour differences (ΔΕ*ab) were much less than 1 at both time points. According to dental colour matching this difference would be considered not perceivable by eye. A variance components analysis (JMP 11) was used to determine how much of the variability in the data was due to measurement variation i.e. the repeatability of measurements made on the same day. The analysis showed that 1.1, 1.0, 0.1 and 0.2% of the variability was due to measurement variation for L, a, b and WIO respectively.
Conclusions: The results indicate that the DigiEye system is applicable for repeatable tooth colour and whiteness measurements in vitro.