White-Spot Quantification Using Enhanced White Light and Fluorescence Imaging

Objectives: The aim of this study was to evaluate the correlation between actual mineral loss in white-spot lesions and the fluorescence loss values calculated by a device based on fluorescence imaging with reflectance enhancement. 

Methods: Forty (40) extracted human teeth having unstained, carious white spots were selected.  Twenty (20) smooth-surface white-spot lesions and twenty (20) occlusal white-spot lesions were imaged with the investigational device.  The fluorescence loss percentage value in a small area within the region of each white-spot lesion was automatically calculated by the device’s software.  After imaging, a tooth section was carefully taken from the quantified area on each white spot and processed for transverse microradiography (TMR) analysis to determine mineral loss and lesion depth.  One and two samples were lost from the occlusal and smooth-surface groups, respectively.  Pearson’s correlation coefficients (R²) were calculated between the set of fluorescence loss values calculated by the investigational device and the sets of mineral-loss and lesion-depth values generated from TMR analysis.  P-values were also determined to test for statistical significance of the results.

Results:  

Surface type	R2 between mineral loss and fluorescence loss	P-value
Smooth Surface (N = 18)	0.683	<0.005
Occlusal Surface (N = 19)	0.202	<0.250

 

Surface Type	R2between lesion depth and fluorescence loss	P-value
Smooth Surface (N = 18)	0.539	<0.025
Occlusal Surface (N = 19)	0.325	<0.100

Conclusions:  

The study demonstrated a statistically significant correlation between the demineralization level of white-spot lesions on smooth tooth surfaces and fluorescence loss percentage as calculated by the investigational device, but no such correlation was found on the occlusal surface.  Correlation between the depth of white-spot lesions on smooth surfaces and calculated fluorescence loss was also found to be significant but not as strong as that between mineral loss and calculated fluorescence loss.