Raman and IR reflection micro‐spectroscopic study of Er:YAG laser treated permanent and deciduous human teeth

Abstract

Permanent and deciduous human teeth treated by a dental Er‐doped yttrium‐aluminium‐garnet pulse laser (λ = 2940 nm) as well as by classical drilling tools under conditions typical of the clinical practice were studied by ultraviolet Raman and Fourier transform infrared (FTIR) reflection microspectroscopy. Enamel was analyzed by both spectroscopic methods, whereas dentine was studied only by FTIR reflection because of the high level of photoluminescence continuum background even when a wavelength of 325 nm was used in inelastic light scattering experiments. The applied energy and pulse frequency of the dental laser varied between 200 and 500 mJ and between 10 and 30 Hz, respectively. The most important result is that after the laser treatment, the hydroxyapatite structure in both permanent and deciduous enamel is preserved: the apatite Ca‐P‐O framework remains intact, and the content of channel OH‐ groups is not changed within experimental uncertainties. The calcium‐phosphate framework of dentine also exhibits negligible laser‐induced changes. The only alterations in enamel induced by laser as well as by mechanical drilling are reduction of the amount of CO32‐ in apatite and changes in the protein conformation. The laser impact on the organic material and carbonate groups is strongest for laser power of 8 W; for powers of 4 or 5 W, the combination of higher pulse energy and lower pulse frequency has less impact than the combination of lower energy and higher frequency. No differences between deciduous and permanent teeth in their resistivity to laser irradiation with λ = 2940 nm were detected. Copyright © 2013 John Wiley & Sons, Ltd.

Development of a new approach to diagnosis of the early fluorosis forms by means of FTIR and Raman microspectroscopy

“…Raman spectroscopy is most often used for diagnostics of dental diseases as a non-destructive method of analysis, which allows to obtain direct data regarding the local atomic structure, chemical and molecular composition of biological objects 18,20,24,[27][28][29] . Also, the hard tissue of a human tooth can be investigated by infrared spectroscopy methods [30][31][32][33][34] , which due to minimal external influences, has not been modified by the method 35 .…”

Chemical and mechanical properties of snake fangs

“…[44] Raman spectroscopy has also been employed to monitor how different treatments affect the dental structures. [45][46][47][48][49] Xu et al examined the correlation between the distribution of carbonate content in enamel and the associated structural and mechanical properties. [27] Univariate (peak width) and bivariate (carbonate to phosphate ratio) methods were employed to compare the Raman (chemical) information to hardness.…”

“…Studies have been employed to look at the chemical and structural changes across the different domains of teeth; some examples include inspection of the enamel–dentine junction, carious and hypomineralized lesions . Raman spectroscopy has also been employed to monitor how different treatments affect the dental structures . Xu et al examined the correlation between the distribution of carbonate content in enamel and the associated structural and mechanical properties .…”

Recent advances in linear and nonlinear Raman spectroscopy. Part VIII

“…[99] Jegova and coworkers carried out a microspectroscopic Raman and IR reflection study of Er:YAG laser treated permanent and deciduous human teeth. [100] Liu and coworkers used near-infrared SERS (NIR-SERS) for the detection of oxyhemoglobin (OxyHb) in liver cancer using a polyvinyl alcohol (PVA)-Ag nanofilm. Their study demonstrates great potentials for developing NIR-SERS OxyHb analysis into a novel clinical tool for noninvasive detection of liver cancers.…”

“…The results demonstrate that Raman spectroscopy can discriminate between different molecular subtypes of glioma and, therefore, may prove to be a valuable tool in in vitro cancer research . Jegova and coworkers carried out a microspectroscopic Raman and IR reflection study of Er:YAG laser treated permanent and deciduous human teeth . Liu and coworkers used near‐infrared SERS (NIR‐SERS) for the detection of oxyhemoglobin (OxyHb) in liver cancer using a polyvinyl alcohol (PVA)‐Ag nanofilm.…”