MINERAL LOSS IN INCIPIENT CARIES LESIONS QUANTIFIED WITH LASER FLUORESCENCE AND LONGITUDINAL MICRORADIOGRAPHY - A METHODOLOGIC STUDY

The laser fluorescence method (LAF) was validated with Longitudinal mi croradiography (LMR) For assessment of mineral loss in incipient carie s lesions in human enamel. Fluorescence radiance scans and LMR recordi ngs were made of 36 enamel slabs with incipient lesions. Original soun d values for fluorescence radiance and enamel amount (kg . m(-2)) at t he lesion site were reconstructed by a computer algorithm. Changes in fluorescence radiance and amount of enamel in each measuring point wer e calculated. The reconstruction method was tested on 20 sound enamel surfaces. The differences between measured and reconstructed values we re -0.13 +/- 0.17% with LAF and 0.002 +/- 0.005 kg . m(-2) with LMR. T he repeatability of the caries quantification was tested by measuring one lesion 20 times. The fluorescence loss in this lesion was 18.2 +/- 1.0%. The enamel loss was 0.09 +/- 0.02 kg . m(-2). The correlation b etween measurements with the two methods was r = 0.73. The non-destruc tive laser fluorescence method was concluded to be a sensitive and val id method For quantification of mineral loss in enamel caries lesions.