Effects of Er,Cr:YSGG laser and a bioactive glass on root caries remineralization

Abstract

Considering the aging of the population, the greater exposure of the root surfaces and the higher caries risk in these surfaces, the development of strategies that efficiently remineralize root caries lesions in a long-lasting way is strictly necessary. This in vitro blind randomized study evaluated the potential of remineralization of root caries lesions promoted by Er,Cr:YSGG laser irradiation (2.78 μm) associated with a bioactive glass (Biosilicate ®). 60 bovine root dentin slabs with incipient caries lesions were distributed in 6 experimental groups {n:::15l, in order to be treated with laser irradiation (0.25W, 12.5 mJ/pulse, 2.8 J/cm2, 20 Hz, without refrigeration), application of Biosilicate® or association of both. After the treatments, the samples were subjected to an 8-day pH-cycling regimen, and further evaluated by Fourier transformed infrared spectroscopy {FTIR), optical coherence tomography (OCT) and scanning electron microscopy. The data were statistically analyzed at a 5% significance level. The Biosiljcate ® promoted the formation of carbonated hydroxyapatite even before loser irradiation, which was better retained after demineralization in loser irradiated group. The Biosilicote® and the la ser irradiation alone provided the remineralization of the root dentin in a similar way to that promoted by the topical application of acidulated phosphate fluoride, since all groups had comparable optical attenuation coefficients. The association of the Biosilicate® with the loser irradiation showed higher optical attenuation coefficient than the other experimental groups. It was concluded that the association of Biosilicote® with laser irradiation promoted a synergistic effect, augmenting the remineralization of root dentin and preventing the progression of caries.