Mh. Vanderveen et Jj. Tenbosch, AUTOFLUORESCENCE OF BULK SOUND AND IN-VITRO DEMINERALIZED HUMAN ROOT DENTIN, European journal of oral sciences, 103(6), 1995, pp. 375-381
The aim of this paper is to report on the demineralization-induced cha
nges in dentin autofluorescence. Confocal laser scanning microscopy (C
LSM) images and fluorescence excitation and emission spectra of in vit
ro demineralized root surfaces and sound controls on the same tooth ro
ots were compared. When observed in CLSM images, demineralized dentin,
excited at 488 nm, gave an increased emission at 529 nm compared to s
ound dentin. The difference in fluorescence decreased deeper into the
root, as the sound dentin underneath the lesion was reached. In contra
st, when using fluorescence spectrophotometry, excitation around 460 a
nd 488 nm yielded a lower emission around 520 nm for demineralized den
tin than for sound dentin, but in a more pronounced peak. From excitat
ion spectra for emission around 520 nm, it could be seen that in demin
eralized dentin the contribution of excitation between 480 and 520 nm
was more important than in sound dentin. The recorded fluorescence in
CLSM images was not affected by demineralization-caused changes in sca
ttering and absorption properties, due to the small measurement volume
. Thus, the increased fluorescence for demineralized dentin implies an
increased quantum yield. In fluorescence spectrophotometry, where the
measurement volume is large, changes in scattering and absorption do
have an influence on the fluorescence signal. Then, increased absorpti
on by non-fluorescing chromophores and increased re-absorption around
the emission wavelength may compensate for the increase in quantum yie
ld and absorption around the excitation wavelength by fluorophores.