In Situ Effect of Intra-Oral Application of Pastes Containing CPP-ACP or CPP-ACPF Against Initial Enamel Erosion

Objective: To evaluate in situ the effect of toothpastes containing casein phosphopeptide - amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide-amorphous calcium phosphate associated to fluoride (CPP-ACPF) on initial erosion prevention. Material and Methods: Bovine enamel blocks (n = 192) were randomly assigned into 4 phases according to the baseline surface hardness: GI: CPP-ACP Paste (MI Paste™), GII: CPP-ACPF Paste (MI Paste Plus™), GIII: Fluoridated paste and GIV: Placebo Paste. In each of the 4 crossover phases, twelve volunteers wore intraoral palatal appliances containing 4 enamel blocks for 2 hours, then the tested treatments were applied intraorally (3 min) and the appliance was maintained in the mouth for another 3 hours. After, the appliances were removed and immersed in hydrochloric acid (0.01 M, pH 2.3) for 30 seconds to promote erosive demineralization. The final surface hardness was evaluated and percentage of surface hardness loss was calculated. The data were analyzed by ANOVA and Tukey's test (α = 5%). Results: The application of CPP-ACP paste, independent of fluoride content, resulted in significant lower enamel hardness loss (GI: 9.26% ±3.48 and GII: 9.14% ±1.73) compared to NaF (GIII: 15.5% ± 3.94) and placebo (GIV: 16.7% ± 4.07) pastes, which did not show difference between them. Conclusion: The CPP-ACP pastes were able to reduce initial erosive demineralization in relation to fluoride and placebo pastes. Nevertheless the formulation of CPP-ACP with fluoride did not provide an additional benefit.

Effect of calcium fluoride on the activity of dentin matrix-bound enzymes.

OBJECTIVE: Matrix metalloproteinases (MMPs) and cysteine cathepsins (CCs) are two distinct enzymatic pathways responsible for the degradation of collagen fibrils in demineralized dentin. NaF and KF have been shown to inhibit salivary MMP-2, -9 and CCs. This study investigated the inhibitory effect of calcium fluoride (CaF2) on the dentin matrix-bound MMPs and CCs. DESIGN: Phosphoric acid (10%)-demineralized dentin beams (1 × 2×6 mm) were incubated at 37 °C in an 1 ml of artificial saliva (AS, control), or AS with 6, 12, 24, 48, 120. 179 and 238 mM F containing CaF2 (n = 10/group) for 1, 7 and 21 days. All groups were further incubated in AS only for 6 months. Total MMP activity, dry mass loss, CTX and hydroxyproline (HYP) analyses were performed after each incubation. The beams were examined under scanning electron microscopy (SEM). MMP-2 and MMP-9 activities were screened with gelatin zymography. Data were analyzed by using ANOVA and Tukey HSD tests (p = .05). RESULTS: The total MMP activity was similar for all groups after 21 days and 6 months. After 21 days, the cumulative mass loss and CTX levels were lower compared to control for the CaF2 ≥48 and CaF2≥120 mM, respectively (p < .05). After 6 months, no significant difference was detected in the dry mass loss and CTX compared to the control (p > .05), whereas HYP level was higher with F 24 and 238 mM groups. CaF2-like minerals were observed on the beams under SEM. There was no gelatinase inhibition in zymography. CONCLUSION: CaF2 does not prevent the degradation of demineralized dentin matrices due to the catalytic activity of MMPs and CCs.

Design of multifunctional alkali ion doped CaF2 upconversion nanoparticles for simultaneous bioimaging and therapy.

Herein, alkali ion doped CaF2 upconversion nanoparticles (UCNPs) were first reported as a multifunctional theranostic platform for dual-modal imaging and chemotherapy. Interestingly, we found that the alkali ions doping approach could efficiently enhance the upconversion luminescence (UCL) intensity, whereas slightly affect the phase and morphology of the resulting products. In order to further improve the UCL efficacy for bioimaging, a pristine CaF2 shell was grown on the CaF2:Yb, Er core surface to enhance the UCL intensity. After being transferred into hydrophilic UCNPs, these water-soluble UCNPs could be served as contrast agents for in vitro/in vivo UCL imaging and X-ray computed tomography (CT) imaging. Furthermore, the as-prepared UCNPs could also be employed as nano-carriers for drug delivery. Doxorubicin (DOX) can be easily loaded onto the UCNPs and the DOX-loaded UCNPs exhibit a good cell killing ability. Therefore, the multifunctional core-shell CaF2 UCNPs with UCL/CT imaging and drug carrier properties may find extensive applications in simultaneous imaging diagnosis and therapy.

Therapeutic effect of two fluoride varnishes on white spot lesions: a randomized clinical trial

The aim of this randomized clinical trial study was to evaluate the therapeutic effect of two varnish formulations (G1 = 5 percent NaF, G2 = 6 percent NaF + 6 percent CaF2) on the remineralization of white spot lesions (WSL). The sample was composed of 15 (7- to 12-year-old) children with 45 active WSL in anterior permanent teeth. The children were randomly divided into two groups providing 22 lesions for G1 and 23 for G2. The children were submitted to weekly varnish applications 4 times. The WSL were evaluated twice: baseline and on week 4. Maximum lesion dimensions (mesiodistal and incisogingival) were measured in millimeters and classified in four grades of size. WSL were also assessed regarding lesion activity by one calibrated examiner. The Pearson chi-square and Fisher's exact tests were used (P < 0.01). WSL reductions were observed in both varnish groups (Chi-square = 0.15, d.f. = 1, P = 0.90), and with similar magnitude (in mm): 1.19 and 1.29 for G1 and G2, respectively. Thirty-six WSL (15 in G1 and 21 in G2) were classified as inactive on week 4, reaching an overall value of 80 percent. No difference was observed between G1 and G2 regarding activity scores (Fisher's exact test, p > 0.01). It was concluded that after 4 applications the two varnish formulations tested produced similar clinical effects, indicating the reduction and the control of carious activity in most WSL.

Urinary fluoride output in children following the use of a dual-fluoride varnish formulation

OBJECTIVE: This study evaluated the bioavailability of fluoride after topical application of a dual-fluoride varnish commercially available in Brazil, when compared to DuraphatTM. MATERIAL AND METHODS: The urinary fluoride output was evaluated in seven 5-year-old children after application of the fluoride varnishes, in two different phases. In the first phase (I), children received topical application of the fluoride varnish Duofluorid XII (2.92 percent fluorine, calcium fluoride + 2.71 percent fluorine, sodium fluoride, FGM TM). After 1-month interval (phase II), the same amount (0.2 mL) of the fluoride varnish Duraphat (2.26 percent fluorine, sodium fluoride, ColgateTM) was applied. Before each application all the volunteers brushed their teeth with placebo dentifrice for 7 days. Urinary collections were carried out 24 h prior up to 48 h after the applications. Fluoride intake from the diet was also estimated. Fluoride concentration in diet samples and urine was analyzed with the fluoride ion-specific electrode and a miniature calomel reference electrode coupled to a potentiometer. Data were tested by ANOVA and Tukey's post hoc test (p<0.05). RESULTS: There were significant differences in the urinary fluoride output between phases I and II. The use of Duofluorid XII did not significantly increase the urinary fluoride output, when compared to baseline levels. The application of Duraphat caused a transitory increase in the urinary fluoride output, returning to baseline levels 48 h after its use. CONCLUSIONS: The tested varnish formulation, which has been shown to be effective in in vitro studies, also can be considered safe.

Análise in vitro do fluoreto no esmalte humano decíduo após tratamento com géis fluoretados / CCAF2 uptake on deciduos human enamel after fluoridated gels treatment in vitro

O objetivo deste estudo foi verificar, in vitro, a deposiçäo do fluoreto de cálcio (CaF²) após aplicaçäo de géis fluoretados neutro e acidulado sobre as superefícies hígida (H) e desmineralizada (D) do esmalte dental decíduo. Foram utilizadas 96 seçöes de esmalte, obtidas de 24 segundos molares decíduos, que foram divididas em quatro grupos: 1) HA, tratado com FFA; 2) DA, com FFA; 3) HN, com gel neutro; 4) DN, com gel neutro. As amostras foram tratadas durante 1 min e 4min. A deposiçäo de Caf² foi analisada pelo método de CASLAVSKA et al. (3) e os resultados, submetidos ao teste estatítico de Wilcoxon. Foi possível constatar a presença do Caf² após todos os tratamentos, porém ela foi maior no tempo de 4min. Quando foram comparados os dois produtos, tanto sobre os esmaltes H e D, a diferença foi estatisticamente significativa apenas com 4min de tratamento. Ao serem comparados os dois tipos de esmalte, näo foram observadas diferenças estatisticamente significativa, entre os dois produtos. Os resultados demonstraram que houve deposiçäo de Caf² decorrente da aplicaçäo tópica dos géis fluoretados na superfície dos dois tipos de esmalte, existindo uma relaçäo direta com o tempo de tratamento

A deposiçäo de fluoreto de cálcio no esmalte dentário humano in vitro após tratamento com soluçöes fluoretadas para bochechos / The calcium fluoride deposition on human dental enamel in vitro after treatment with fluorides solutions for mouthrinse

O objetivo da investigaçäo foi verificar a deposiçäo de fluoreto de cálcio na superfície do esmalte dentário humano in vitro, após tratamento com quatro produtos comerciais, contendo soluçöes para bochechos com fluoreto de sódio a 0,05 por cento. Foram também comparados os resultados decorrentes da aplicaçäo de duas soluçöes de composiçäo similar, mas com diferentes pHs. Todos os produtos foram aplicados por 1 hora e a quantidade de fluoreto de cálcio depositada foi determinada por análise química. Os resultados demonstraram que a quantidade de fluoreto de cálcio depositado foi extremamente reduzida, indicando a possibilidade da interferência de indutores na composiçäo dos produtos. Quando foi observado o comportamento das soluçöes com diferentes pHs, as diferenças na quantidade de fluoreto de cálcio depositada näo foram estatisticamente significativas

A scanning electron microscope investigation of calcium fluoride-like material deposited during topical fluoride exposure on sound human enamel in vitro

1. The morphological aspects of globules deposited in vitro when a NaF solution is applied to sound human enamel were studied by scanning electron microscopy. 2. Particles, presumably of calcium fluoride-like material, formed on the surfaces of an unerupted tooth and consisted of subunits showing a "cauliflower" appearance, idnciating agglomeration of even smaller particles. The number and size of the crystals increased with time of exposure. 3. These particles represent highly resistant fluoride reservoirs and may be of clincial significance