Dentin and enamel are the two main constituents of human teeth, and the detailed characterization of their biochemical properties is of fundamental relevance in many fields of dentistry research. Vibrational spectroscopies such as Fourier Transform Infrared (FT-IR) and Raman spectroscopy can be adopted to obtain precise information before and after chemical or physical teeth treatments [1-4].
In the present work, the two above-mentioned spectroscopic techniques have been used for investigating dentin and enamel powders and few-mm thick disks cut from human molar teeth. The teeth were sectioned vertically with a diamond saw. After preparation, the samples were stored in a dry state. Before laser processing, they were rehydrated with distilled water for 24 hours to restore the normal fully hydrated state. FT-IR spectra were acquired on dried samples in micro-ATR mode in the 4000-650cm−1 wavenumber range using the microscope stage of a Perkin-Elmer SpectrumOne spectrometer with an MCT detector. Raman spectra were collected in the 400-3200cm-1 spectral range using a confocal Raman microscope (Horiba Xplora) with a Peltier-cooled CCD, a 50X objective, and a 785nm laser.
FT-IR and Raman spectra clearly show the contributions of different sample components. The spectra obtained from dentin and enamel powders evidence the differences due to their chemical composition. The spectra from human tooth disks present different characteristics depending on the region of the samples from which they were collected, thus enabling a spatial characterization of the samples themselves on different scales. These results confirm that vibrational spectroscopies allow a detailed characterization of hard dental tissues at the microscopic level.
References
[1]K.B.Beć, J. Grabska,C. W. Huck, Analytica Chimica Acta 1133, 150e177 (2020).
[2]I.Otel, Quantum Beam Sci. 7, 5 (2023).
[3]C.Diez, M.Á.Rojo, J.Martín-Gil, P.Martín-Ramos, M.Garrosa, D.Córdoba-Diaz, Minerals 12, 28 (2022).
[4]M.Anwar Alebrahim, C.Krafft, J.Popp, IOP Conf.Series:Materials Science and Engineering 92, 012014 (2015).