This in vitro study compared the efficiency (time taken to excavate and successfully remove bacterially infected dentin) of Fluorescence Aided Caries Excavation (FACE), caries detector dye (CD), chemomechanical excavation (CS) and conventional excavation (CE). Teeth with dentin caries were assigned to 4 groups (n= 25). Caries excavation was carried out by one operator. In the FACE group, the operating field was illuminated with violet light. The operator observed the teeth through a high-pass filter and removed orange-red fluorescing areas with a slow speed bur. In the CS group, Carisolv was applied to the cavity using CS hand instruments and allowed to act for 30 seconds before caries was removed. In the CD group, caries was removed using the Caries Detector and, in the CE group, conventional excavation was carried out using visual-tactile criteria. The excavation time was recorded. Undecalcified thin slices (8 microm) were prepared, stained with giemsa and examined using light microscopy. The excavation time (median) was significantly shorter for FACE (3 minutes, 3 seconds) compared to CS (5 minutes, 8 seconds, p=0.015), CD (5 minutes, 26 seconds, p=0.003) and CE (4 minutes, 2 seconds, p=0.025). Histology showed remaining bacteria in significantly fewer (5/25) FACE samples compared to CS (15/25 p=0.004) CD (12/25 p=0.037) but not significantly fewer than CE (11/25 p=0.069).
In conclusion: the excavation result with FACE is equal to CE and superior to CD and CS but requires a significantly shorter excavation time.