Color Changes in Artificially Induced Incipient Caries after Photodynamic Therapy with Different Concentrations of Methylene Blue and Toluidine Blue and Irrigation with Water and Hypochlorite.

AIM

The aim of this study was to assess the color changes in artificially induced incipient caries after photodynamic therapy (PDT) using different concentrations of methylene blue and toluidine blue, along with irrigation using water and hypochlorite.

MATERIALS AND METHODS

Forty-two sound human premolar teeth were used to create two artificial incipient carious lesions. One lesion was placed on the buccal surface and the other on the lingual surface. The color of these artificial incipient carious surfaces was determined using the CIE       color system. The teeth were then randomly assigned to 12 groups ( = 7) based on the PDT method. These methods included methylene blue with concentrations of 50, 100, and 150 g/mL, followed by water irrigation, methylene blue with concentrations of 50, 100, and 150 g/mL, followed by hypochlorite solution irrigation, toluidine blue with concentrations of 50, 100, and 150 g/mL, followed by water irrigation, and toluidine blue with concentrations of 50, 100, and 150 g/mL, followed by hypochlorite solution irrigation. The teeth underwent a colorimetry procedure again, and the resulting color changes were calculated. A three-way ANOVA was performed to analyze the effects of laser wavelength, concentration of the light-absorbing material, and irrigation solution on .

RESULTS

The results showed that the color changes caused by toluidine blue photosensitizer at a concentration of 100 g/mL, with both water and hypochlorite irrigation, were not noticeable to the naked eye (water = 3.04, hypochlorite = 2.00). However, in the other study groups, the color changes were perceptible ( > 3.3). There were no significant differences in between different concentrations of methylene blue and toluidine blue when using either water or hypochlorite irrigation (  > 0.05). A significant difference was observed between methylene blue and toluidine blue at a concentration of 100 g/mL with water irrigation (=0.006). Additionally, a significant difference was found between methylene blue and toluidine blue at a concentration of 100 g/mL with hypochlorite irrigation (=0.049). However, no significant differences were observed between methylene blue and toluidine blue at other concentrations with either water or hypochlorite irrigation (  > 0.05).

CONCLUSION

In conclusion, tooth color in teeth with incipient caries did not change significantly after PDT using toluidine blue (the photosensitizer) at a concentration of 100 g/mL with either water or 1% hypochlorite solution irrigation for 5 s.