title: CO₂ laser emission modes to control enamel erosion.
abstract: Considering the importance and prevalence of dental erosion, the aim of this in vitro study was to evaluate the influence of different modes of pulse emission of CO2 laser associated or not to acidulated phosphate fluoride (APF) 1.23% gel, in controlling enamel erosion by profilometry. Ninety-six fragments of bovine enamel were flattened and polished, and the specimens were subjected to initial erosive challenge with hydrochloric acid (pH = 2). Specimens were randomly assigned according to surface treatment: APF 1.23% gel and gel without fluoride (control), and subdivided according to the modes of pulse CO2 laser irradiation: no irradiation (control), continuous, ultrapulse, and repeated pulse (n = 12). After surface treatment, further erosive challenges were performed for 5 days, 4 × 2 min/day. Enamel structure loss was quantitatively determined by a profilometer, after surface treatment and after 5 days of erosive challenges. Two-away ANOVA revealed a significant difference between the pulse emission mode of the CO2 laser and the presence of fluoride (P ≤ 0.05). The Duncan's test showed that CO2 laser irradiation in continuous mode and the specimens only received fluoride, promoted lower enamel loss than that other treatments. A lower dissolution of the enamel prisms was observed when it was irradiated with CO2 laser in continuous mode compared other groups. It can be concluded that CO2 laser irradiation in continuous mode was the most effective to control the enamel structure loss submitted to erosive challenges with hydrochloric acid.
authors.affiliation: Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, 14040-904, Brazil.
authors.forename: Renata Siqueira
authors.initials: RS
authors.lastname: Scatolin
authors.affiliation: Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, 14040-904, Brazil.
authors.forename: Fernando Luiz
authors.initials: FL
authors.lastname: Alonso-Filho
authors.affiliation: Department of Dental Materials and Prosthodontics, Araraquara Dental School, State Sao Paulo University, Araraquara, São Paulo, 14803-901, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Galo
authors.affiliation: Department of Pediatric Dentistry, Orthodontics and Public Health, Dental School of Bauru, University of São Paulo, Bauru, São Paulo, 17012-901, Brazil.
authors.forename: Daniela
authors.initials: D
authors.lastname: Rios
authors.affiliation: Department of Pediatric Clinics, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, 14040-904, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Borsatto
authors.affiliation: Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, 14040-904, Brazil.
authors.forename: Silmara Aparecida Milori
authors.initials: SA
authors.lastname: Corona
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000737:chemistry*; D002417:Cattle; D003743:Dental Enamel / Q000528:radiation effects* / Q000648:ultrastructure; D007180:Incisor / Q000528:radiation effects; D054020:Lasers, Gas; D008853:Microscopy; D014077:Tooth Erosion
chemical_list: D002245:Carbon Dioxide
keywords: enamel loss; fluoride; hydrochloric acid; lasers