Effect of green tea-loaded chitosan nanoparticles on leathery dentin microhardness

Autor(es)

Curylofo-Zotti, Fabiana Almeida ; Tedesco, Antonio Claudio ; Lizarelli, Gustavo Teodoro Costa ; Takahashi, Luandra Aparecida Unten ; Corona, Silmara Aparecida Milori

• Tipo de documento: Artigo Científico
• Fonte: ODONTOLOGY; v. 109, n. 4, p. 8-pg., 2021-05-08.

Resumo

The purpose of this study was to assess the effect of a chitosan-based nanoformulation containing green tea on leathery (remaining) dentin subsurface microhardness. Size distribution, polydispersity index (PDI) and zeta potential (mV) of nanoformulations were previously determined by dynamic light scattering (DLS). Human dentin specimens were exposed to Streptococcus mutans for 14 d. Soft dentin were selectively removed by Er:YAG laser (n = 30) or bur (n = 30). Remaining dentin was biomodified with chitosan nanoparticles (Nchi, n = 10) or green tea-loaded chitosan nanoparticles (Gt + Nchi, n = 10) for 1 min. Control group (n = 10) did not receive any treatment. Subsurface microhardness (Knoop) was evaluated in hard (sound) and soft dentin, and then, in leathery dentin and after its biomodification, at depths of 30, 60 and 90 mu m from the surface. Nchi reached an average size of <= 300 nm, PDI varied between 0.311 and 0.422, and zeta potential around + 30 mV. Gt + Nchi reached an average size of <= 350 nm, PDI < 0.45, and zeta potential around + 40 mV. Soft dentin showed significantly reduced microhardness at all depths (p > 0.05). The subsurface microhardness was independent of choice of excavation method (p > 0.05). At 30 mu m from the surface, Gt + Nchi increased the leathery dentin microhardness compared to untreated group (p < 0.05). Nchi promoted intermediate values (p > 0.05). Both nanoformulations showed an average size less than 350 nm with nanoparticles of different sizes and stability along the 90-day period evaluated. Subsurface microhardness of bur-treated and laser-irradiated dentin was similar. At 30 mu m, the biomodification with Gt + Nchi improved the microhardness of leathery dentin, independently of caries excavation method used. (AU)

• Processo FAPESP: 17/11582-1 - Biomodificação da dentina com nanopartículas de quitosana fosforilada (NanoQF) após remoção seletiva da lesão de cárie com laser de Er:YAG: Avaliação das propriedades antimicrobianas e físico-químicas.
• Beneficiário: Fabiana Almeida Curylofo Zotti
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/50181-1 - Utilização de nanocarreadores contendo fármacos fotossensibilizantes e outros ativos aplicados à terapia celular e tratamento de patologias do sistema nervoso central
• Beneficiário: Antonio Claudio Tedesco
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 19/04807-2 - Função das proantocianidinas como nucleadores de biomineralização da dentina
• Beneficiário: Fabiana Almeida Curylofo Zotti
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado