Applications of fluorescence microscopy to studies of dental hard tissue

Abstract

In this review we describe applications of fluorescence microscopy to investigations of dental hard tissue. Many studies have shown that human teeth show autofluorescence and several applications of fluorescence microscopy have been reported, although the chemical nature of autofluorescence remains unknown. However, most applications are based on a static measurement mode, which has inherent limitations. These limitations can be overcome by the use of time-resolved fluorescence microscopy. Therefore, we attempted to combine ordinary and time-resolved fluorescence microscopy to study human dentine. Using stationary measurements, blue fluorescence with a peak of 440 +/- 10 nm and a width of approximately 100 nm was observed. Increases in fluorescence intensity were found to be dependent upon age and temperature, regardless of tooth type or gender. The results suggest that the aging mechanism for crown dentine differs from that for root dentine and that the observed increase in fluorescence intensity is partially due to a temperature-dependent physicochemical mechanism. We speculate that fluorescence microscopy will become a useful tool for analysis of dental hard tissue in several fields.

Fluorescence properties of human teeth and dental calculus for clinical applications

“…12 Studies have shown that human teeth emit autofluorescence, although the exact chemical nature of autofluorescence remains unknown. 13 Autofluorescence of human teeth by the UV light is reviewed in this section.…”

“…Blue fluorescence with a peak of 440 AE 10 nm and a width of ∼100 nm was observed based on stationary measurements of human dentine. 13 To overcome the inherent limitations of the static measurement of fluorescence, time-resolved fluorescence microscopy was used to investigate the fluorescence of human dentine. 13 Fluorescent emission of human teeth may vary by the type of teeth, age, and other factors.…”

“…13 To overcome the inherent limitations of the static measurement of fluorescence, time-resolved fluorescence microscopy was used to investigate the fluorescence of human dentine. 13 Fluorescent emission of human teeth may vary by the type of teeth, age, and other factors. To establish the normal range of fluorescence of human teeth, each type of tooth from the mandibular and maxillary arch were examined.…”

“…There was no difference in fluorescence intensity between tooth types (incisors, canine, premolar, and molar) taken from the same individual. 13,29 Since enamel, dentine, and pulp suffer noticeable changes during an individual's lifetime, fluorescence of teeth would vary by aging. Enamel becomes more mineralized with time because of the absorption of ions from saliva and foods, and dentine becomes thicker with time as pulp decreases in volume due to the deposition of secondary dentine.…”

Rare Earth Oxide-containing Fluorescent Glass Filler for Composite Resin

“…If the composite resin shows some distinct optical feature, easy visual inspection of the restored part could be achieved. Fluorescence is a good property for use as a non-contact detection method in various materials and has already been applied in many fields [9][10][11] . The authors have also applied the fluorescence detection method for the discrimination of esthetic restoratives 12,13) .…”