OBJECTIVE: Distinguishing between cariogenic and noncariogenic discoloration is crucial to avoid unnecessary removal of dental tissue. This study aimed to investigate the efficacy of biofluorescence bleaching (BF-bleaching) for identifying cariogenic discoloration in human teeth with naturally discolored pits and fissures. METHODS: Sixty-nine extracted human permanent teeth with discolored pits and fissures associated with suspected occlusal caries were included. A dental bleaching agent (15% H RESULTS: Prebleaching ΔR values were significantly lower in the NCD and masked CD groups (p<
0.001). ΔR in masked CD increased by 15% after 5 minutes (p<
0.001), becoming similar to those in exposed CD. ΔR in NCD and exposed CD showed no significant changes at any time point. The h° value of masked CD decreased by 2.05°, shifting from orange to red after 20 minutes. In contrast, the h° of NCD group remained stable within the orange hue range. After 5 minutes, ΔR sensitivity increased from 0.79 to 0.90, and h° AUC improved from 0.69 to 0.93. CONCLUSION: Bleaching of pits and fissures exhibiting caries-related discoloration effectively removes the overlying stains, revealing the lesion's underlying red biofluorescence. Thus, BF-bleaching can be a useful method for the objective diagnosis and monitoring of cariogenic discoloration. CLINICAL SIGNIFICANCE: Using BF-bleaching for accurate evaluation of CD will help provide minimally invasive preventive and treatment options.