2009 Volume 52 Issue 5 Pages 384-392
A caries detector dye, 1% acid red in propylene glycol, has been generally used for minimal removal of carious lesions. However, the evaluations of the degree of staining are subjective. Therefore, a new caries detector dye, 1% acid red in polypropylene glycol, Caries Check® (Nippon Shika Yakuhin) was developed for minimal and objective removal of carious lesions. In this study, the objectivity of removal of caries was evaluated using the new caries detector dye by the color evaluation method, a laser fluorescence device, DIAGNOdent® (KaVo, DIAGNOdent) and the bacterial method. Twenty-one cases of coronal dentin caries (eight human extracted molars) were divided into two groups. The carious lesions were removed by two examiners using the new caries detector dye until the color of the dentin surfaces was not stained. Then, the dentin surfaces were evaluated using the DIAGNOdent, images of the surfaces with a color-matching sticker were acquired using a CCD camera, and dentinal tissue samples were collected with a new round bur. Corrected L*, a* and b* values of the surfaces (CIE 1976 L* a* b* color system) were calculated from the color changes of the stickers in the images. On the other hand, bacterial DNA in dentinal carious tissues was detected by the polymerase chain reaction (PCR) using the universal primers based on the nucleotide sequences of a conserved region of the 16S rDNA. The intra-class correlation coefficients of the corrected L*, a*, b* and DIAGNOdent values were 0.16, 0.18, 0.86 and 0.51. There were significant differences between b* values of two examiners and between DIAGNOdent values of them (p<0.05). In eight of the 21 cases, bacterial DNA was found in the dentinal tissues after removal of carious tissues. The results suggest that the objectivity of caries removal using the new caries detector dye, Caries Check®, with visual inspection is not high.
