Quantitative lightinduced fluorescence

Quantitative Light-induced Fluorescence (QLF) is one method of assessing levels of enamel demineralization. With QLF, real-time fluorescent images are captured into a computer and stored in an image database. Optional quantitative analysis tools enable the user to quantify parameters like mineral loss, lesion depth, lesion size, stain size and severity with high precision and repeatability. The QLF method is based on the auto-fluorescence of teeth. When teeth are illuminated with high intensity blue light they will start to emit light in the green part of the spectrum. When enamel demineralization takes place, minerals are replaced mainly by water from saliva, causing a decrease in the light path in the tooth substance. This results in less light absorption by enamel. Because fluorescence is a result of light absorption, the intensity of fluorescence decreases in demineralized regions of the enamel, which appear darker than sound tooth structures (de Josselin et al., 1995; al-Khateeb et al., 1998; Rousseau et al., 2002). Thus, the fluorescence of the dental tissue has a direct relation with the mineral content of the enamel. The effectiveness of QLF for measurement of enamel demineralization has been demonstrated in several studies. The use of QLF allows for quantitative analysis has been reported to be well correlated (0.73-0.83) with the degree of mineral loss from early enamel lesions in-vitro when measured by longitudinal microradiography. (Hafstrom-Bjorkman et al., 1992; Emami et al., 1996; Lagerweij et al., 1996). The use of QLF as a method of following caries development during orthodontic treatment has been suggested and encouraged by the results of several in-vitro studies. (Benson et al., 2003 and Pretty et al., 2003). Recent studies also indicate that QLF is suitable for in-vivo monitoring of mineral changes in incipient enamel lesions (Van der Veen et al., 2000 and Al Khateeb et al, 2002).

0 0

Post a comment