Dental Enamel Remineralization Following Diode Laser Irradiation

Caries is a globally important public health problem that affect teeth and may also cause problems for systemic health. High power lasers have been studied as a adjuvant therapy for caries prevention and remineralization. Furthermore, OCT has been proposed as a diagnostic tool for dental caries due to changes in the optical properties of enamel after demineralization. The aim of this study was to evaluate the effects of diode laser irradiation on enamel remineralization. Bovine enamel blocks were prepared and submitted to caries lesion formation using an in vitro microbial model. Samples were incubated with Streptococcus mutans suspended in a medium supplemented with sucrose during 4 days and were additionally exposed to 10% sucrose 10 times/day. Then, caries lesion were irradiated with a 808 nm diode laser (1 W, irradiance of 35.7 J/cm2, during 10 s) and were submitted to remineralization process for 7 days. A commercial Optical Coherence Tomography system, with wavelength of 930 nm, was used to analyse the samples after caries formation and after remineralization process. OCT detected enamel mineral loss promoted by caries lesion formation. After induction of remineralization, samples without treatment did not presented alteration in reflectivity data suggesting no increase in mineral content. However, irradiated samples showed a significant decrease in reflectivity results (P < 0.05). Our data showed that diode laser irradiation successfully induce enamel remineralization.