Influence of Er,Cr:YSGGLaseron CaF₂-like products formation because of professional acidulated fluoride or to domestic dentifrice application

Abstract

This study evaluated the synergy of professional acidulated fluoride gel (APF) or fluoridated dentifrice application combined with Er,Cr:YSGG laser irradiation on the formation of CaF2 -like products (CaF2 ), in vitro. Thus, 272 bovine enamel slabs were randomly distributed among eight groups: G1: untreated enamel; G2: treated with fluoridated dentifrice (NaF, 1,100 μgF/g); G3: treated with acidulated phosphate fluoride gel (APF, 1.23% F(-) ); G4: irradiated with Er,Cr:YSGG laser at 8.5 J/cm(2) ; G5 and G6: combination of pre-irradiation with Er,Cr:YSGG followed by dentifrice or APF application, respectively; G7: combination of dentifrice application followed by Er,Cr:YSGG irradiation; G8: combination of APF application followed by Er,Cr:YSGG irradiation. After treatments, samples were evaluated by scanning electron microscopy, and the content of CaF2 was determined by an ion specific electrode. Both APF and dentifrice application promoted the formation of CaF2 on enamel, whereas Er,Cr:YSGG irradiation promoted an increase of roughness of the enamel, increasing the surface area. Laser irradiation before fluoridated products increased the content of CaF2 formed when compared to groups that APF or dentifrice were applied isolated. However, the content of CaF2 formed when irradiation was performed after APF or dentifrice was not statically significant when compared to the control groups. In conclusion, Er,Cr:YSGG laser increases the formation of CaF2 on enamel when the irradiation is performed before the application of APF or dentifrice. The association of laser with APF is most promissory for caries prevention because of the higher concentration of CaF2 formation and also the chemical changes promoted by laser irradiation demonstrated in literature.

Erbium Lasers for the Prevention of Enamel and Dentin Demineralization: A Literature Review

“…36 For LIPD, some studies suggested performing the irradiation with low energy densities and without water cooling to avoid ablation of the target tissue. 20,38,64 Some studies showed that the presence of water in large amounts during irradiation would increase the chance of ablation as well as the porosity of the dental surface, which would facilitate the diffusion of acids into the enamel structure, increasing the depth of demineralization. 65,66 However, satisfactory results have been achieved with or without the use of cooling, although its role in the mechanism of LIPD is yet to be clearly established.…”

“…The development of long-lasting demineralization prevention treatment continues to be a target for the field of dentistry, especiallyfor patients with poor dietary habits and oral hygiene, or with compromised motility. 20 Additionally, dental caries and dental erosion may be a problem among the elderly, especially considering the increasing prevalence of root caries 21,22 and dental erosion. 23 The possibility of increasing the acid resistance of enamel after laser irradiation was first reported in 1965 with a ruby laser.…”

“…59 The exposition of the hydroxyapatite rods and, as a consequence, increasing the roughness of enamel were also reported with Er,Cr:YSGG laser irradiation (8.5 J/cm 2 ). 20 It was reported that subablative Er:YAG and Er:YSGG irradiation produced fine cracks in the enamel surface, and the depth of the cracks could be observed over 100 lm depth. 34 According to the authors, these cracks acted as starting points for acid attack and favored deep demineralization; therefore, these changes would reduce or eliminate the positive effect of LIPD.…”

ATR-FTIR Assessment of the Biochemical Composition and Micro Hardness of the Hard Tissues of Oral Cavity Submitted to Gamma Irradiation

“…Recent study [5] from the Biophotonics Laboratory of the Nuclear and Energy Research Institute-IPEN (São Paulo-Brazil) showed that, enamel submitted to ionizing radiation might not be more susceptible to demineralization than non-irradiated enamel, observed in vitro. For root dentin, with higher organic content than enamel, it was the most affected by gamma radiation compared to enamel ad coronary dentin, as demonstrated in the literature [6][7][8].…”

In Vitro Assessment of the Composition and Microhardness of the Hard Tissues of Oral Cavity Submitted To Gamma Irradiation

“…It has been defined as the irradiated necrotic bone exposed, which does not heal over a period of three or six months without the presence of tumor remained or tumor recurrence. This pathological entity covers both jaws, the upper jaw region and the mandibular region, with a high incidence rate in the region of the mandibular body and retro molar region documented in recent years [4][5][6][7].…”