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PubMed · 17045384

Laser-induced compositional changes on enamel: a FT-Raman study.

Yuanyuan Liu·Chin-Ying Stephen Hsu
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Abstract

UNLABELLED: Preventive effects of lasers on enamel caries have been documented in the past few decades. However, its specific mechanism remains uncertain. OBJECTIVES: To evaluate the laser-induced change of enamel compositions, including carbonate and organic matters using Fourier-transform Raman spectroscopy (FT-Raman). METHODS: Twelve windows (1 mm x 1 mm), created on six defect-free primary incisors, were characterized by FT-Raman microscopy (1024 nm) before and after Er:YAG laser treatment (Fidelis) with 5.1 J/cm(2)-2 Hz-5s. To assess the statistical significance of laser effects, Raman peaks assigned to nu(1) phosphate, type-A/B carbonates, and organic matters were evaluated with the paired-samples t-test. RESULTS: The standardized intensity of type B carbonate decreased significantly from 0.117 to 0.106 (p=0.029), whereas the standardized intensity of carbonate A remained unchanged (p=0.467). Related to organic matters, the standardized intensity of peaks at 2940 cm(-1) and in the ranges of 1200-1600 cm(-1) decreased significantly, with p=0.005 and p<0.001, respectively. Revealing enamel crystallinity, the bandwidth of nu(1) phosphate on lased surfaces appeared to be unaltered after laser treatment (p=0.477). CONCLUSIONS: Laser treatment may provide caries-preventive effect on enamel through reduction of carbonate and modification of organic matters.

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Aluminum SilicatesAmidesCarbonCarbonatesCrystallographyDental EnamelErbiumHumansHydrogen BondingLasersOrganic ChemicalsPhosphatesSpectroscopy, Fourier Transform InfraredSpectrum Analysis, RamanYttriumJournal ArticleResearch Support, Non-U.S. Gov't

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Yuanyuan Liu, Chin-Ying Stephen Hsu. 2006-10-11. Laser-induced compositional changes on enamel: a FT-Raman study.. https://doi.org/10.1016/j.jdent.2006.08.006

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