Cyclodextrin and TiF4 Nanocomplex on Enamel Demineralization

• Published in: Brazilian dental journal 2020-08, Vol.31 (4), p.423-430
• Main Authors: Vieira, Thiago, Alexandria, Adílis K., Amaral, Lilian H., Neves, Aline de A., Lopes, Ricardo T., Cabral, Lúcio M., Valença, Ana M. G., Maia, Lucianne C.
• Format: Article
• Language: English
• ISSN: 0103-6440; 1806-4760
• DOI: 10.1590/0103-6440202002531

Abstract The aim of this study was to assess the effect of a newly developed nanocomplex formed of hydroxypropyl-b-cyclodextrin and 1% titanium tetrafluoride (TiF4) after distinct complexation periods (12/72 h) on demineralization of bovine enamel in vitro. Enamel blocks (n=60) were allocated in different groups: Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4, hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h of complexation and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation. The samples were evaluated by surface microhardness, cross-sectional microhardness and micro-CT. Scanning electron microscopy and energy dispersive X-ray spectrometry (SEM/EDX) were also obtained. Hydroxypropyl-b-cyclodextrin + 1% TiF4 after 12 h complexation resulted in lower percentage of surface microhardness loss compared to Mili-Q water, hydroxypropyl-b-cyclodextrin, 1% TiF4 and hydroxypropyl-b-cyclodextrin + 1% TiF4 after 72 h of complexation group, with a large effect size (from 1.307 to 2.943) and high power (84.9 to 99%). All groups resulted in similar integrated mineral loss (ΔZ) obtained by both internal microhardness and micro-CT techniques. Enamel treated with TiF4 and TiF4 + hydroxypropyl-b-cyclodextrin groups showed a TiO2 glaze-layer, while EDX evaluation identified Ti. The solution containing the inclusion complex of hydroxypropyl-b-cyclodextrin + TiF4 with 12 h of complexation period demonstrated a significant ability to reduce surface demineralization of sound enamel under an artificial cariogenic challenge. Resumo O objetivo deste estudo foi avaliar o efeito da 1-etil-3- (3-dimetilaminopropil) carbodiimida (EDC) na resistência de união de pinos de fibra de vidro em canais radiculares obturados com diferentes cimentos endodônticos. Setenta e oito pré-molares inferiores foram obturados com três cimentos endodônticos (n=26): Endofill (END), AH Plus (AHP) e Endosequence BC Sealer (EBS). Após o preparo do espaço para pino, dois subgrupos formaram-se conforme a cimentação dos pinos (n=13): com EDC e sem EDC (controle - CON). Os espécimes foram submetidos ao teste pull-out, classificação do modo de falha e avaliação da superfície do canal radicular por microscopia eletrônica de varredura após o deslocamento. Quanto à força de resistência de união, uma diferença estatisticamente significativa ocorreu entre os subgrupos EDC e CON apenas no END (p=0,001). Não foi detectada diferença entre os subgrupos CON (p=0,339). Contudo, no subgrupo EDC, o AHP apr