Measuring color change of tooth enamel by in vitro remineralization of white spot lesion.

Abstract

Objective colour determination is based on calculating the colorimetric distance (ΔE) within a colour space. So far, the most used colour space in dentistry is CIE L*a*b (Comission Internationale de l´Éclairage). CIE L*C*h* has been recently developed, showing a better correlation with the perception of the human eye. Objective: To determine the ability of an in vitro remineralisation substance to blend the colour of white spot lesions (WSL) with sound enamel, determining ΔE by using the CIE L*C*h* colour space. Methods: In vitro WSL was generated by immersing 10 samples obtained from human third molars in a demineralization solution for 72h. Amorphous calcium phosphate stabilized by casein phosphopeptide (CPP-ACP) was then applied for 60 days while maintaining the samples in artificial saliva at 37ºC. To evaluate the colour of enamel, images were taken from the samples placed in specifically designed silicone moulds after generating the WSL (pre-stage) and after remineralisation by scanning, applying the colorimetric distance equation (ΔE*CMC) according to the Colour Measurement Committee. Results: Treatment with CPP-ACP caused a significant ΔE decrease with respect to the pre-stage (p<0.001), while the analysis of parameters that make up the colour showed a reduction in the difference of hue (ΔH) (p<0.001) and brightness (ΔL) (p<0.01) after applying CPP-ACP. Discussion: CPP-ACP penetrated to the depth of the white spot lesion, making its appearance similar to that of the sound enamel, probably because of the formation of different mineral phases than that of the original structure, although pores were not completely filled.

Color Stability of Artificial White Spot Lesions treated with Resin Infiltration

“…37 Therefore, higher color change values and increased darkness upon staining. 31 Samples immersed in artificial saliva showed color change values higher than both CPP-ACP and resin infiltration. One possible explanation is that artificial saliva resulted only in deposition of minerals on the surface layer leaving the body of the lesion demineralized.…”

“…White spot lesions (WSLs) are early signs of demineralization process resulting in chalky white appearance of the enamel surface. 31 Several ways have been proposed for treatment of WSLs. However, some socially consumed beverages, such as coffee, Coca-Cola and tea may result in discoloration of the WSLs even after treatment.…”

“…One possible explanation is that artificial saliva resulted only in deposition of minerals on the surface layer leaving the body of the lesion demineralized. 3,31,38 This incomplete penetration of calcium and phosphate ions into the enamel pores as shown in Figure (1,e) allowed the yellow stains present in coffee to permeate the lesions.…”

An In Vitro Study on the Effect of Amorphous Calcium Phosphate and Fluoride Solutions on Color Improvement of White Spot Lesions

“…Our results showed statistically significant differences in ∆E3 between the ACP groups and the saliva group. Tolcachir et al [ 17 ] found that CPP-ACP penetrated to the depth of the WSL and turned its appearance similar to that of the sound enamel. In their study, CPP-ACP caused a noticeable change in color of WSLs.…”

Effectiveness of Organic Versus Inorganic Analogues for Treating White Spot Lesions: An in Vitro Study

“…After detecting the opaque white area, an acid etchant of 35% phosphoric acid solution (Ultradent Products Inc., South Jordan, Utah, USA) was applied to the chalky area of the tooth for 30 seconds, which was followed by rinsing with distilled water, and then air-dried. This treatment effectively removed the white opaque layer, exposing the WSLs (8) .…”