Impact of Experimental Nano-HAP Pastes on Bovine Enamel and Dentin Submitted to a pH Cycling Model

Autor(es)

Livia P. Comar ^[1] ; Beatriz M. Souza ^[2] ; Luiz Fernando Gracindo ^[3] ; Marilia A. R. Buzalaf ^[4] ; Ana Carolina Magalhaes ^[5]

Afiliação do(s) autor(es)

^[1] USP - University of Sao Paulo. Bauru Dental School. Department of Biological Sciences - Brasil

^[2] USP - University of Sao Paulo. Bauru Dental School. Department of Biological Sciences - Brasil

^[3] USP - University of Sao Paulo. Bauru Dental School. Department of Biological Sciences - Brasil

^[4] USP - University of Sao Paulo. Bauru Dental School. Department of Biological Sciences - Brasil

^[5] USP - University of Sao Paulo. Bauru Dental School. Department of Biological Sciences - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Dental Journal; v. 24, n. 3, p. 273-278, 2013-06-00.

Resumo

This in vitro study evaluated the preventive potential of experimental pastes containing 10% and 20% hydroxyapatite nanoparticles (Nano-HAP), with or without fluoride, on dental demineralization. Bovine enamel (n=15) and root dentin (n=15) specimens were divided into 9 groups according to their surface hardness: control (without treatment), 20 Nanop paste (20% HAP), 20 Nanop paste plus (20% HAP + 0.2% NaF), 10 Nanop paste (10% HAP), 10 Nanop paste plus (10% HAP + 0.2% NaF), placebo paste (without fluoride and HAP), fluoride paste (0.2% NaF), MI paste (CPP-ACP, casein phosphopeptide-amorphous calcium phosphate), and MI paste plus (CPP-ACP + 0.2% NaF). Both MI pastes were included as commercial control products containing calcium phosphate. The specimens were treated with the pastes twice a day (1 min), before and after demineralization. The specimens were subjected to a pH-cycling model (demineralization–6-8 h/ remineralization-16-18 h a day) for 7 days. The dental subsurface demineralization was analyzed using cross-sectional hardness (kgf/mm 2 , depth 10-220 µm). Data were tested using repeated-measures two-way ANOVA and Bonferroni's test (p<0.05). The only treatment able to reduce the loss of enamel and dentin subsurface hardness was fluoride paste (0.2% NaF), which differed significantly from the control at 30- and 50-µm depth (p<0.0001). The other treatments were not different from each other or compared with the control. The experimental Nanop pastes, regardless of the addition of fluoride, were unable to reduce dental demineralization in vitro. (AU)

• Processo FAPESP: 09/08518-3 - Avaliação do efeito de uma pasta experimental com nanopartículas de fosfato de cálcio sobre a desmineralização da dentina in vitro
• Beneficiário: Luiz Fernando Gracindo
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 10/07001-4 - Avaliação do efeito de uma pasta experimental com nanosparticulas de fosfato de cálcio sobre a desmineralização de esmalte in vitro
• Beneficiário: Beatriz Martines de Souza
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica