Objective: This in vitro study aimed to evaluate the physical and chemical changes promoted by a CO(2) laser at 10.6-microm wavelength on primary dental enamel with artificial caries-like lesions.
Background data: Several previous investigations have shown that enamel can be modified by CO(2) laser to obtain a caries-preventive effect, but the specific mechanism remains uncertain.
Materials and methods: Twenty-seven primary molars were randomly assigned to three groups as follows: control, carious, and laser (n = 9). The specimens from the carious and laser groups were demineralized and treated with or without CO(2) laser, according to the group. Enamel surface changes after treatments were monitored using Fourier transform Raman spectroscopy and scanning electron microscopy (SEM).
Results: The Raman spectra showed a statistically significant reduction of mineral content in carious and laser groups when compared to control group. Additionally, carbonate content was reduced in irradiated specimens when compared to the other groups. No physical change was observed in specimens evaluated by SEM.
Conclusion: The results suggest that CO(2) laser irradiation may reduce the carbonate content of enamel, which is likely to make this substrate more acid-resistant.