title: Potential of CO2 lasers (10.6 µm) associated with fluorides in inhibiting human enamel erosion.
abstract: This in vitro study aimed to investigate the potential of CO2 lasers associated with different fluoride agents in inhibiting enamel erosion. Human enamel samples were randomly divided into 9 groups (n = 12): G1-eroded enamel; G2-APF gel; G3-AmF/NaF gel; G4-AmF/SnF2 solution; G5-CO2 laser (λ = 10.6 µm)+APF gel; G6-CO2 laser+AmF/NaF gel; G7-CO2laser+AmF/SnF2solution; G8-CO2 laser; and G9-sound enamel. The CO2 laser parameters were: 0.45 J/cm2; 6 μs; and 128 Hz. After surface treatment, the samples (except from G9) were immersed in 1% citric acid (pH 4.0, 3 min). Surface microhardness was measured at baseline and after surface softening. The data were statistically analyzed by one-way ANOVA and Tukey's tests (p < 0.05). G2 (407.6 ± 37.3) presented the highest mean SMH after softening, followed by G3 (407.5 ± 29.8) and G5 (399.7 ± 32.9). Within the fluoride-treated groups, G4 (309.0 ± 24.4) had a significantly lower mean SMH than G3 and G2, which were statistically similar to each other. AmF/NaF and APF application showed potential to protect and control erosion progression in dental enamel, and CO2 laser irradiation at 0.45J/cm2 did not influence its efficacy. CO2 laser irradiation alone under the same conditions could also significantly decrease enamel erosive mineral loss, although at lower levels.
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Universidade de São Paulo - USP, São Paulo, SP, Brazil.
authors.forename: Thayanne Monteiro
authors.initials: TM
authors.lastname: Ramos-Oliveira
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Universidade de São Paulo - USP, São Paulo, SP, Brazil.
authors.forename: Thaysa Monteiro
authors.initials: TM
authors.lastname: Ramos
authors.affiliation: Department of Operative Dentistry, Periodontology and Preventive Dentistry, RWTH Aachen University, Aachen, Germany.
authors.forename: Marcela
authors.initials: M
authors.lastname: Esteves-Oliveira
authors.affiliation: Department of Operative Dentistry, Periodontology and Preventive Dentistry, RWTH Aachen University, Aachen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Apel
authors.affiliation: Department of Dental Materials and Biomaterials Research, RWTH Aachen University, Aachen, Germany.
authors.forename: Horst
authors.initials: H
authors.lastname: Fischer
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Universidade de São Paulo - USP, São Paulo, SP, Brazil.
authors.forename: Carlos de Paula
authors.initials: Cde P
authors.lastname: Eduardo
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade Nove de Julho - UNINOVE, São Paulo, SP, Brazil.
authors.forename: Washington
authors.initials: W
authors.lastname: Steagall
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Universidade de São Paulo - USP, São Paulo, SP, Brazil.
authors.forename: Patricia Moreira de
authors.initials: PM
authors.lastname: Freitas
mesh_terms: D000704:Analysis of Variance; D002327:Cariostatic Agents / Q000627:therapeutic use*; D019343:Citric Acid / Q000737:chemistry; D003743:Dental Enamel / Q000187:drug effects* / Q000528:radiation effects*; D005460:Fluorides, Topical / Q000627:therapeutic use*; D006245:Hardness Tests; D006801:Humans; D054020:Lasers, Gas / Q000627:therapeutic use*; D011897:Random Allocation; D012016:Reference Values; D015203:Reproducibility of Results; D013499:Surface Properties / Q000187:drug effects / Q000528:radiation effects; D014077:Tooth Erosion / Q000517:prevention & control*
chemical_list: D002327:Cariostatic Agents; D005460:Fluorides, Topical; D019343:Citric Acid