ft-raman spectroscopic characterization of enamel surfaces irradiated with er:yag and nd:yag lasers

background and aims: although dental caries is a preventable disease, it is still common and remains a public health problem. one of the potentially effective preventive measures is laser irradiation. raman spectroscopy is a powerful technique for studying the microcrystalline structure of dental enamel. the study assessed the chemical alterations occurring in enamel irradiated with er:yag or nd:yag lasers, by means of ft-raman spectroscopy. material and methods: fifteen freshly-extracted human molars were treated as follows: no treatment in group a (n=5); 10 seconds irradiation with er:yag laser at 4 mm from the tooth surface, under water and air spray, in group b (n=5); 10 seconds irradiation with nd:yag laser, at 1 mm from the tooth surface, with 300 µm fiber used in a sweeping motion, in group c (n=5). after treatment, specimens were analyzed by ft-raman spectroscopy. results: analysis of the carbonate content in terms of the integrated area under the curve (1065/960cm–1) showed a statistically-significant reduction in the integrated area ratio, in both laser-irradiated groups. the integrated area of organic content (2935/960 cm-1) showed a statistically-significant reduction after laser irradiation, in both irradiated groups. conclusions: the results show that laser irradiation affects both mineral and organic matrix of dental enamel, and may thus be a suitable strategy for caries prevention; the ft-raman technique appears appropriate to detect such compositional and structural changes.