QLF -Quantitative light-induced fluorescence

Definition

QLF is a technique that uses visible light to detect the demineralization of enamel and tooth decay (de Josselin de Jong et al. 1995) ¹. The light has a frequency range between 370 and 500 nm. The light intensity of the autofluorescence of the tooth (Al Maaitah et al. 2011)².

Mechanism

Areas with tooth decay have the already mentioned already mentioned increased proportion of pores. Here, either less fluorescent light intensity is generated or the light is reflected away from the sensor. Carious areas appear dark on the screen.  QLF has its strength in the field of diagnosis of initial Enamel caries, smooth occlusal surfaces and tooth decay monitoring³. Quantitative: the higher the numerical value, the more tooth decay. Approximale diagnostics due to quantification difficult, generally difficult repositioning.

References

1. de Josselin de Jong EF, Sundstrom F, Westerling H, Tranaeus S, ten Bosch, Angmar-Mansson JJ 1995. A new method for in vivo quantification of changes in initial enamel caries with laser fluorescence. Caries Research 29 (1): 2-7.
2. Al Maaitah EF, Adeyemi AA, Higham SM, Pender N, Harrison J 2011. Factors affecting demineralization during orthodontic treatment: A post-hoc analysis of RCT recruits. American Journal of Orthodontics and Dentofacial Orthopedics 139(2): 181-191.

3. Pretty IA, Edgar WM, Higham SM (2002): Detection of in vitro demineralization of primary teeth using quantitative light-induced fluorescence (QLF). International Journal of Paediatric Dentistry 12, 158-167.