The sugarcane cystatin (CaneCPI-5) was recently cloned and showed strong binding force to dental enamel and protection against initial erosion. However, evaluations on its safety and efficacy in a situation closer to the clinical condition are necessary. In the present study we analyzed 1) the cytotoxicity of CaneCPI-5 on human gingival fibroblasts (HGFs); 2) the ability of CaneCPI-5 to reduce enamel erosion and erosion+abrasion in situ. In part 1, HGFs were treated with CaneCPI-5 (0.025, 0.05, 0.1, 0.5 or 1.0 mg/mL) or no treatment (control). The cytotoxicity was assessed after 60 s and 24 h by mitochondrial activity (MTT), confocal microscopy, and hematoxylin/eosin staining. In part 2, 15 volunteers participated in a double-blind crossover protocol consisting of 3 phases, according to the following treatments: 1) 0.1 mg/mL CaneCPI-5; 2) SnCl₂/NaF/AmF (Elmex; positive control); 3) water (negative control). The volunteers wore an appliance containing 4 bovine enamel specimens for 5 d. Each day, the specimens were individually treated with 50 µL of the tested solutions per 60 s and then subjected to erosive challenges (0.1% citric acid, pH 2.5, for 90 s, 4 times per day). After the first and last erosive challenge each day, 2 samples were abraded (toothbrushing, 15 s). Enamel wear was measured by contact profilometry. One or two-way analysis of variance (ANOVA)/Tukey’s or Sidak’s tests ( P < 0.05) were applied. Regardless of the concentration and the experimental time, CaneCPI-5 did not decrease the cell viability compared to the negative control ( P < 0.05). Erosion+abrasion led to significantly greater wear compared to erosion only. For both conditions, the lowest wear was found for SnCl₂ and CaneCPI-5, which did not differ significantly from each other, but showed significant protection when compared to the negative control. In conclusion, CaneCPI-5 is safe on HGFs and reduces enamel erosive wear to the same extent as a commercial solution used to control erosive tooth wear (ETW).

This randomized three-armed controlled clinical trial compared the effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) varnishes on caries control in smooth surfaces of permanent dentition and children's acceptability. Sixty children (6-8 y/o) were randomly divided into TiF4 (2.45% F-), NaF (2.26% F-) or placebo (control) groups. Varnishes were applied on permanent teeth once a week for the first 4 weeks and after the 6th and 12th months of the study. The variables were as follows: International Caries Detection and Assessment System (ICDAS) scores, quantitative fluorescence changes, visual plaque index (VPI) and degree of acceptability. Two-way RM-ANOVA, ANOVA/Tukey and χ2 tests were performed (p < 0.05). No differences were found between the treatments with respect to ICDAS scores (p = 0.32). Only TiF4 reduced the mean fluorescence loss significantly at 18 months compared to the baseline (p = 0.003). TiF4 showed a lower percentage of new caries lesions by tooth surface than the placebo, while NaF did not induce such a change (p < 0.014). Regardless of the treatment, more than 95% of the participants reported being satisfied. For all groups, the VPI decreased significantly at 3 months compared to the baseline value (p < 0.001), with no differences between the treatments (p = 0.17). TiF4 had a similar ability to control caries lesions as NaF; however, only TiF4 differed from the placebo (p = 0.004). The acceptability of TiF4 varnish was similar to that of NaF varnish.

Objectives. To analyze changes in the dental fluorosis (DF) incidence according to a birth cohort and explore current exposure to DF in a case series. Methods. Repeated cross-sectional study of two periods: 2015 and 2018. Two standardized examiners registered DF using the Thylstrup-Fejerskov index in permanent teeth of children aged 7–18 years. Period and birth cohort frequencies were estimated by a generalized linear model, binomial family, and logarithmic link function. Period estimates are presented as prevalence ratios (PR) and birth cohort estimates as cumulative incidence ratios (RR); 95% confidence intervals and $P$ values are reported. In a subsample of 37 volunteers (12.29 ± 2.63 years), the fluoride (F) concentration in toenails was measured using the HMDS diffusion method and an ion-specific electrode. Other samples from the local environment such as food, soil, and coal were also collected. Results. In 274 children, we found that nonsignificant increases between periods (PR = 1.17; 95% CI: 0.89–1.55) were not explained by birth cohort effects. A total of 37.8% of the subsample had a toenail F concentration ≥2 μg F/g. The salty snacks and seasoning had the highest F concentrations among local environmental samples. Conclusion. In this population with a high DF frequency according to birth cohort and the evaluated period, the study of soil, coal, and food samples indicated a continued F exposure. F concentration found in the toenails shows a moderate F exposure; nearly a third of the children and adolescents exceeded the adopted threshold of 2 μg F/g. It is important to monitor and explore changes in exposure in highly affected population.

The use of fluoride (F) in the prevention of dental caries is established. However, a high amount of F intake during tooth development can cause dental fluorosis The aim of this study was to analyze variations in F concentrations in chocolate bars (CB), chocolate cookies (CC), infant cereals (IC), and chocolate milk drinks (CD) to determine the daily intake of F from different sources by children at the age of risk for developing dental fluorosis. Distinct brands of CB, CC, IC, and CD were analyzed. Fluoride was separated by hexamethyldisiloxane-facilitated diffusion. Analysis was made in triplicate with an F ion-specific electrode. F ingestion (mg/kg body weight) was evaluated with the suggested consumption (0.05–0.07 mg/kg/day) for children aged 24 months (12 kg). The concentrations for all the analyzed products ranged from 0.025 to 1.827 µg/g F. The mean (range) F concentrations were CB= 0.210 ± 0.205 µg/g (0.073–0.698, n = 8), CC = 0.366 ± 0.416 µg/g (0.320–1.827, n = 9), IC = 0.422 ± 0.395 µg/g (0.073–1.061, n = 5), and CD = 0.169 ± 0.170 µg/mL (0.025–0.443, n = 12). The products that had the highest concentration in the categories CB, CC, IC, and CD, respectively, were Nescau-Ball (0.698 µg/g), Passatempo (1.827 µg/g), Milnutri (1.061 µg/g), and Toddynho (0.443 µg/mL). The consumption of only one unit of Toddynho (CD) is equivalent to more than 11% of the maximum suggested daily intake for a 24-month-old child (0.07 mg/kg body weight). When one product from each category is consumed together only once a day, this consumption is equivalent to approximately 24% of the suggested daily intake of fluoride for a 24-month-old child. The presence of high levels of fluoride in certain products suggests that they play a significant role in overall fluoride intake. It is crucial to closely monitor the fluoride content of food and drinks that are consumed by children who are at risk for dental fluorosis, and for product labels to clearly display the fluoride concentrations.