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Tooth Whitening Materials
Published in Linda Greenwall, Tooth Whitening Techniques, 2017
Some products in this category contain titanium dioxide, a white pigment found in paint. It acts by entering the surface irregularities of the tooth (Haywood 1995b) and gives the illusion of whitened teeth. Only a surface phenomenon, titanium dioxide does not penetrate internally and thus does not modify the internal color or whiten teeth. Other ingredients include tetrasodium pyrophosphate for the soothing effect on the teeth as well as sodium lauryl sulphate for the foaming capability and hydrated silica.
Effect of experimental toothpaste containing hydroxyapatite nanoparticles and propolis, with and without fluoride, on the microcosm biofilm and enamel demineralization
Published in Biofouling, 2023
Caroline Fernanda da Silva Ribeiro, Aline Dionizio, Tamara Teodoro Araújo, Chelsea Maria Vilas Boas Feitosa Rodrigues, Amanda Costa Mattos, Letícia Galli Otaviano, Larissa Tercília Grizzo, Ana Carolina Magalhães, Marília Afonso Rabelo Buzalaf
Enamel specimens were randomly divided into the 9 treatment groups, according with the treatments (Table 1): (1) Placebo - negative control of toothpastes (pH 8.9); (2) 1500 ppm F commercial toothpaste - Positive Control – Gold Standard (Crest®, P&G; 1500 ppm F as NaF, sorbitol, water, hydrated silica, sodium lauryl sulfate, trisodium phosphate, flavor, sodium phosphate, cellulose gum, sodium saccharin, carbomer, titanium dioxide and colour; pH 7.1); (3) Premium toothpaste (10% nanoHAP, 5% propolis, 3% xylitol; pH 7.06); (4) Premium +Fluoride toothpaste (10% nanoHAP, 5% propolis, 3% xylitol, 1500 ppmF as NaF; pH 7.18); (5) Combat toothpaste (5% nanoHAP, 2% propolis, 1% xylitol; pH 7.45); (6) Combat + Fluoride toothpaste (5% nanoHAP, 2% propolis, 1% xylitol, 1500 ppmF as NaF; pH 6.54); (7) Fluoride + Propolis toothpaste (2% propolis, 1500 ppmF as NaF; pH 8.41); (8) 0.12% CHX - PerioGard® solution (Colgate, São Bernardo do Campo, Brazil) - positive control and (9) phosphate-buffered saline (PBS) solution - negative control. The placebo and test toothpaste were prepared by Apis Vida Ind. Com. Prod. Farmacêuticos Ltda. (Bebedouro, Brazil). They had the same composition, except for the active ingredients.
The health effects of short fiber chrysotile and amphibole asbestos
Published in Critical Reviews in Toxicology, 2022
Chrysotile was first described as being decomposed by acid by von Kobell (1834). Chrysotile has the approximate composition Mg3Si205(OH)4 and is a sheet silicate composed of silicate and brucite layers (magnesium hydroxide octahedra). The different dimensions of these two components result in a structural mismatch in which the layers curl concentrically or spirally (Pauling 1930). The fiber walls are made up of ∼12–20 of these layers in which there is some mechanical interlocking. However, there is no chemical bonding as such between the layers. Each layer is about 7.3 A° thick, with the magnesium hydroxide part of each layer closest to the fiber surface and the silicon-oxygen tetrahedra “inside” the curl (Whittaker 1957, 1963; Tanji 1984; Titulaer et al. 1993, Table 2). Hargreaves and Taylor (1946) reported that if fibrous chrysotile is treated with dilute acid, the magnesia can be completely removed. The hydrated silica, which remains, though fibrous in form, had completely lost the elasticity characteristic of the original chrysotile and had a structure that was “amorphous” or “glassy” in type.
In vivo evaluation of fluoride and sodium lauryl sulphate in toothpaste on buccal epithelial cells toxicity
Published in Acta Odontologica Scandinavica, 2019
Antonija Tadin, Lidia Gavic, Tanja Govic, Nada Galic, Nada Zorica Vladislavic, Davor Zeljezic
Apart from fluoride as a toxic substance, SLS is often referred to as a common constituent of toothpaste, suspected to be able to induce adverse effects in exposed cells. SLS can change the barrier properties of human oral mucosa in vitro [13] and in vivo [14]. Applying toothpaste with different SLS concentrations from 0.01% to 1.5% directly on the mucosa of volunteering individuals by a cap splint, it was shown that 1.5% SDS causes desquamation of the epithelium in 60% of the subjects [2]. The results of the presented study have shown that Sensodyne brand toothpaste with SLS and fluoride at different testing points (30 and 60 days from the start of using) has significantly higher incidence of pyknotic cells, cells with karyorrhexis and nuclear buds, than toothpaste of the same brand with fluoride but without SLS for the same period of usage. Plidenta toothpaste with SLS has shown only significantly higher incidence in some pyknotic cells in the first month, compared to Plidenta toothpaste with fluoride but without SLS after 30 and 60 days of use. It is clear that the usage of both tested brands leads to an increase in the number of cells with pyknosis. Pyknosis is an alteration in the level of apoptosis, as well as karyorrhexis and condensed chromatin. Sensodyne toothpaste, as a surfactant, in addition to SLS, also contains Cocamidopropyl Betaine (CAPB). It is possible that their combination is the reason for increasing the several cytogenetic parameters, compared to Plidenta toothpaste where the surfactant is only SLS. In vitro data regarding CAPB are conflicting. Different in vitro studies found that CAPB has more toxic, similar or less toxic effect, compared to SLS [37–39]. On the other hand, in vivo studies proved CAPB to be the cause of a measurable mucosal irritation, corresponding to the effect of SLS [40]. Also, other ingredients, including silicon dioxide, hydrated silica, sodium benzoate, preservatives, dyes, flavours, and essences may also exhibit toxic effects [2,41].