Time-resolved SWIR imaging for the assessment of the activity of
occlusal caries lesions
The aim of this study was to develop a clinical SWIR reflectance
handpiece to assess the activity of lesions on the occlusal surfaces.
The time-resolved reflectivity of ten active and ten arrested occlusal
caries lesions on extracted teeth was monitored at 1470 nm using a
benchtop system and a modified clinical prototype during forced air
drying. The presence of a highly mineralized surface zone measured with
microcomputed tomography (microCT) was used to indicate lesion activity.
Multiple kinetic parameters were extracted from the acquired SWIR time
versus intensity dehydration curves and used to assess lesion activity.
Three parameters: delay, %I fin, and rate calculated
from the SWIR dehydration curves were significantly different (P
< 0.05) between active and arrested lesions. The modified
clinical probe was able to completely dehydrate all the active lesion
areas in the occlusal pits and fissures in less than 30 seconds.