title: Impact of CO2 laser and stannous fluoride on primary tooth erosion.
abstract: This study evaluated in vitro the effect of input power of CO2 laser, either associated or not to stannous fluoride (SnF2) gel, for the control of intrinsic erosion in primary teeth. One hundred four enamel slabs (3 × 3 × 2 mm) from human primary molars were flattened and polished. Adhesive tapes were placed on their surface leaving a window of 3 × 1 mm. Slabs were then cycled four times in 0.01 M hydrochloric acid (pH 2, 2 min) and in artificial saliva (2 h) for creation of erosive lesions. Specimens were randomly assigned into eight groups (n = 13) according to fluoride application [absent (control) or 0.4% stannous fluoride gel (SnF2)] and input power of CO2 laser [unlased (control), 0.5, 1.0 or 1.5 W]. The CO2 laser irradiation was performed in an ultra-pulse mode (100 μs of pulse duration), 4-mm working distance, for 10 s. Specimens were then submitted to further erosive episodes for 5 days and evaluated for enamel relative permeability. Fluoride did not show any protective effect for any of the laser-treated groups or control (p = 0.185). However, a significant effect was detected for input power of CO2 laser (p = 0.037). Tukey's test showed that there was a significant statistically difference between specimens irradiated with 0.5 and 1.5 W (p = 0.028). The input power of 0.5 W showed lower permeability. Variation of input power CO2 laser can influence enamel permeability, at the power of 1.5 W which promoted greater permeability.
authors.affiliation: Faculty of Dentistry, Sobral Campus, Federal University of Ceará, Rua Stanislau Frota, s/n, Centro, Sobral, CE, Brazil, 62.010-560. cristianetomaz@hotmail.com.
authors.forename: Cristiane Tomaz
authors.initials: CT
authors.lastname: Rocha
authors.affiliation: Department of Restorative Dentistry, São Leopoldo Mandic Institute and Dental Research Center, Rua Doutor José Rocha Junqueira, 13, Ponte Preta, Campinas, SP, CEP 13045-755, Brazil.
authors.forename: Cecilia Pedroso
authors.initials: CP
authors.lastname: Turssi
authors.affiliation: Department of Social Medicine, Ribeirão Preto School of Medicine, University of São Paulo, Av. do Café, s/n, Monte Alegre, Ribeirão Preto, SP, CEP:14.040-904, Brazil.
authors.forename: Antonio Luiz
authors.initials: AL
authors.lastname: Rodrigues-Júnior
authors.affiliation: Department of Restorative Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Av. do Café, s/n, Monte Alegre, Ribeirão Preto, SP, CEP:14.040-904, Brazil.
authors.forename: Silmara Aparecida Milori
authors.initials: SA
authors.lastname: Corona
mesh_terms: D059248:Chemoradiotherapy; D003743:Dental Enamel / Q000187:drug effects / Q000528:radiation effects*; D006801:Humans; D054020:Lasers, Gas; D010539:Permeability; D014002:Tin Fluorides / Q000494:pharmacology*; D014077:Tooth Erosion / Q000628:therapy*; D014094:Tooth, Deciduous / Q000187:drug effects / Q000528:radiation effects*
chemical_list: D014002:Tin Fluorides
keywords: CO2 laser; Fluoride; Primary teeth; Tooth erosion