NaF Group Research Articles

Effect of silver diamine fluoride/potassium iodide treatment on the prevention of dental erosion in primary teeth: an in vitro study

IntroductionDental erosion has a great effect on oral health, when diagnosed it is irreversible, this sets the importance of different preventive measures being investigated against dental erosion.AimThis in vitro study aims to evaluate the effectiveness of silver diamine fluoride and Potassium iodide (SDF-KI) in comparison to casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) varnish, sodium fluoride (NaF) varnish, silver diamine fluoride (SDF) alone and deionized water as a control group in the prevention of dental erosion in primary teeth and assessing its staining effect.Materials and methodsForty deciduous teeth enamel specimens were randomly allocated into the five study groups. Tested materials were applied. An erosive challenge was done by immersing the specimens in a citric acid-containing soft drink with pH 2.85, for 5 min, 4 times/day, for 5 days. Changes in surface microhardness, mineral loss, and color change were evaluated besides recording of the surface topography and surface roughness for selected specimens.ResultsThe highest decrease in surface microhardness was recorded in the control group (−85.21 ± 10.60%), with a statistically significant difference (p = 0.002). SDF-KI group (−61.49 ± 21.08%) showed no statistically significant difference when compared to CPP-ACPF, NaF, and SDF groups. For calcium and phosphorous loss, control group was statistically significantly higher compared to the treatment groups (p = 0.003) and (p < 0.001) respectively, while there was no statistically significant difference between the tested treatment groups. The highest mean value for color change was recorded in SDF group (26.26 ± 10.31), followed by SDF-KI group (21.22 ± 12.87) with no statistically significant difference between groups.ConclusionsSDF-KI is as effective as CPP-ACPF, NaF varnishes and SDF in the prevention of dental erosion in primary teeth, there was no statistically significant difference regarding its staining potential.

Effect of Dentin Surface Pretreatment With Chitosan Nanoparticles on Immediate and Prolonged Shear Bond Strength of Resin Composite: An in Vitro Study

Introduction: The objective of this study was to evaluate the impact of chitosan nanoparticles’ pretreatment of dentin surface on the macro shear bond strength of resin composite, both immediately and over an extended period. Methods: Thirty caries-free, unrestored human premolars were randomly assigned to six study groups. The dentin surface of the intervention groups underwent pretreatment with 0.2% chitosan and 0.05% NaF solutions for 1 minute. A standard etch-and-rinse adhesive procedure was performed for all the study groups. After 24 hours, half of the specimens underwent a macro shear bond strength test at a crosshead speed of 1 mm/min, whereas the other specimens underwent the same procedure after 300 thermal cycles between 5 and 55°C with a 30-second dwell time in the thermocycling device. Results: The study found that the type of dentin surface treatment agents did not significantly affect the shear bond strength (P = 0.52). However, there were statistically significant differences between immediate and prolonged shear bond strength in the chitosan (P &lt; 0.01) and the control groups (P = 0.005). On the other hand, there were no significant differences between the immediate and prolonged shear bond strength in the NaF group (P = 0.997). Conclusion: Dentin pretreatment with 0.2% chitosan solution did not significantly affect the shear bond strength of the etch-and-rinse adhesive system. Pretreatment with NaF maintained the shear bond strength of the adhesive to dentin after 300 thermal cycles.

Effect of Different Remineralization Agents on Artificial Caries Lesion: An in-vitro Study

Objective: Remineralization technologies have been shown to arrest or reverse early carious lesions. This study aimed to evaluate and compare the effect of different agents on enamel remineralization in-vitro. Methods: Thirty-five enamel blocks were prepared and divided into the following groups: Group 1; CaGp and Xylitol-containing gel (R.O.C.S Medical Mineral Gel), Group 2; 1100 ppm NaF and 10% CPP-ACP toothpaste (MI Paste One), Group 3; 0.45% SnF2-1150 ppm F toothpaste (Enamelon), Group 4; Positive Control-1450 ppm NaF toothpaste (Colgate Total) and Group 5; Negative Control (deionized water). Microhardness was measured at baseline, after demineralization, and after respective treatments for different treatment groups using a digital Micro Vickers Hardness Tester. For producing demineralized lesions, samples were stored in acidic hydroxyethylcellulose (HEC, pH=4.8) for three days. The Paired Sample t-test, one-way ANOVA, and Tukey were used to compare data and SMH recovery (%SMHR) calculated among treatments. Results: The mean baseline surface microhardness value was statistically non-significant between the groups (p=.378). CaGP and Xylitolcontaining gel demonstrated having the most protective effect against demineralization. The surface remineralization potential of 1100 ppm NaF and 10% CPP-ACP containing novel toothpaste (MI Paste One) was almost similar to the positive control (1450 ppm Fluoride toothpaste)group (p&gt;.05). Conclusions: All treatment groups showed remineralization after respective treatments and these agents can be used as an effective preventive measure for pediatric patients.

TGF-β1/Smad3 Signaling Is Required to Alleviate Fluoride-Induced Enamel Hypomineralization.

Excessive fluoride intake during enamel development can affect enamel mineralization, leading to dental fluorosis. However, its potential mechanisms remain largely unexplored. In the present study, we aimed to investigate the impact of fluoride on the expressions of RUNX2 and ALPL during mineralization and the effect of TGF-β1 administration on fluoride treatment. A dental fluorosis model of newborn mice and an ameloblast cell line ALC were both used in the present study. The mice of the NaF group, including the mothers and newborns, were fed with water containing 150ppm NaF after delivery to induce dental fluorosis. The mandibular incisors and molars showed significant abrasion in the NaF group. Immunostaining, qRT-PCR, and Western blotting analysis indicated that exposure to fluoride markedly down-regulated RUNX2 and ALPL in mouse ameloblasts and ALCs. Besides, fluoride treatment significantly decreased the mineralization level detected by ALP staining. Furthermore, exogenous TGF-β1 up-regulated RUNX2 and ALPL and promoted mineralization, while the addition of SIS3 could block such TGF-β1-induced up-regulation. In TGF-β1 conditional knockout mice, the immunostaining of RUNX2 and ALPL was weaker compared with wild-type mice. Exposure to fluoride inhibited the expressions of TGF-β1 and Smad3. Co-treatment of TGF-β1 and fluoride up-regulated RUNX2 and ALPL compared with the fluoride alone treatment, promoting mineralization. Collectively, our data indicated that TGF-β1/Smad3 signaling pathway was necessary for the regulatory effects of fluoride on RUNX2 and ALPL, and the fluoride-induced suppression of ameloblast mineralization was mitigated by activating TGF-β1/Smad3 signaling pathway.

The effect of nintedanib on lung functions and survival in idiopathic pulmonary fibrosis: real-life analysis of the Czech EMPIRE registry

IntroductionThe antifibrotic drug nintedanib is used for the treatment of idiopathic pulmonary fibrosis (IPF). We analysed the effect of nintedanib on antifibrotic treatment outcome in real-world cohorts of Czech EMPIRE registry.Patients/methodsData of 611 Czech IPF subjects, 430 (70%) treated with nintedanib (NIN group), 181 (30%) with no-antifibrotic treatment (NAF group) were analysed. The influence of nintedanib on overall survival (OS), pulmonary function parameters as forced vital capacity (FVC) and diffusing lung capacity for carbon monoxide (DLCO), as well as GAP score (gender, age, physiology) and and CPI (composite physiological index) were investigated.ResultsDuring 2 year follow-up we observed that nintedanib treated patients had longer OS, compared to those treated with no-antifibrotic drugs (p < 0.00001). Nintedanib reduces risk of mortality over no-antifibrotic treatment by 55% (p < 0.001). We have observed no significant difference in the rate of FVC and DLCO decline between the NIN and NAF group. Changes within 24 months from baseline in CPI were not significant between the groups (NAF and NIN).ConclusionOur real-practice study showed the benefit of nintedanib treatment on survival. There were no significant differences between NIN and NAF groups in changes from baseline in FVC %, DLCO % predicted and CPI.

Assessment of the Remineralizing Efficacy of Grape Seed Extract vs Sodium Fluoride on Surface and Subsurface Enamel Lesions: An In Vitro Study.

The aim of this study was to evaluate the efficacy of grape seed extract (GSE) on remineralization of surface and subsurface enamel lesions compared to that of sodium fluoride (NaF). A total of 20 intact bovine incisor crowns were separated from their roots and immersed in a demineralizing solution for 96 hours at 37°C to create artificial enamel lesions. The specimens were randomly divided into two groups (n = 10): 6.5% GSE solution and 1000 ppm NaF solution. The specimens were subjected to six daily pH cycles for 8 days. The microhardness test was carried out at three different stages: baseline, after artificial caries formation, and after pH cycling. Raman spectroscopy was used to evaluate the depth of enamel remineralization. Surface morphology and elemental analysis were assessed using a scanning electron microscope (SEM) and an energy dispersive X-ray (EDX) spectroscope, respectively. Statistical analysis was performed using SPSS 22.0 at a significance level of p ≤ 0.05. There was a significant increase in the mean values of enamel surface microhardness after pH cycles in the two groups compared to after artificial caries formation, but there was no significant difference between both groups. The B-type carbonate/phosphate (Ca/P) ratio at 10 and 40 µm depth revealed no significant difference between the two groups. Scanning electron microscope micrograph revealed occlusion of porosities and particle precipitation on the enamel surface of the two groups, while EDX results for the Ca/P ratio of the GSE and NaF groups were 1.59 and 1.60, respectively. Grape seed extract and NaF are equally effective in remineralizing surface and subsurface artificial enamel lesions. Grape seed extract can be considered a promising herbal material and a safe alternative to traditional NaF for the noninvasive treatment of enamel lesions.

Corrosion of copper nickel titanium archwire in chlorhexidine, sodium fluoride, and chitosan mouthwashes.

Copper (Cu), nickel (Ni), chromium (Cr) ion release, and surface topography change from the orthodontic wire are the initial processes of corrosion that may affect the mechanical properties of the archwire. In this study, we aim to evaluate the effect of CHX, NaF, and chitosan on the corrosion of CuNiTi wire nickel and copper ions released, surface roughness change, and archwire deflection. Ninety samples of CuNiTi Tanzo™ archwires were divided into five groups according to their immersion solution: Artificial Saliva, CHX, NaF, CHX-NaF, and chitosan group. Each group was further divided into three subgroups (n=6) corresponding immersion time, i.e., two, four, and six weeks. The corrosion of the samples was analyzed with an atomic absorption spectrophotometer (AAS), scanning electron microscope (SEM), and universal testing machine (UTM). The amount of nickel ion releases was increasing, but the copper ion releases were reduced by the time of observations. The highest nickel ion was released in the CHX-NaF group and the lowest in the chitosan group for six-week immersion. It also corresponded to the surface topography by SEM analysis which showed the most extended cracks and deep pits in the CHX-NaF group and a smoother surface in the chitosan group. Copper ion release showed the highest ion release in the NaF group and the lowest release in the chitosan group. The unloading force of CuNiTi archwire deflection remains the same at week two and week four for all mouthwashes. The use of mouthwashes that contained CHX, NaF, and chitosan could further alter the passive layer and cause higher nickel and copper ion release and increased CuNiTi archwire surface structure porosity. But there is no distinction between mouthwashes to release the unloading force within two until four weeks.

The remineralization effect of GERM CLEAN on early human enamel caries lesions in vitro

This study aimed to evaluate the remineralization effect of GERM CLEAN, a novel antibacterial peptide, on early enamel caries. Thirty human enamel blocks from thirty teeth were randomly divided into three groups: double distilled water (DDW group), GERM CLEAN (GC group), and 1000 ppm fluoride (NaF group). Specimens were demineralized for 3 days (pH 4.6) followed by pH cycling twice daily for 14 days. For a pH cycle, specimens received corresponding treatments for 5 min, then were immersed in demineralizing solution for 1 h, received corresponding treatments again, and finally were immersed in remineralizing solution (pH 7.0) for approximately 11 h. Specimens were washed with DDW after each treatment. Microindentation tests, atomic force microscopy (AFM), and transverse micro-radiography (TMR) were conducted to analyze enamel blocks. GC demonstrated a lower percentage of surface microhardness recovery (SMHR%) (p < 0.0001), rougher surfaces (p < 0.0001), deeper lesion depth (p = 0.001), and more mineral loss (p = 0.001) than NaF, but showed higher SMHR% (p < 0.0001), smoother surfaces (p < 0.0001), shallower lesion depth (p = 0.049), and less mineral loss (p = 0.001) than DDW. As a result, GERM CLEAN has the potential to promote the remineralization of demineralized enamel.

Effects of Fluoride Exposure on Thiol/ Disulphide Homeostasis, Testicular Oxidative Stress and Histopathological Changes in Rats

Objective: This study investigated the effects of fluoride-induced toxicity on the reproductive system. For this purpose, testicular oxidative stress, thiol/disulpide homeostasis, sperm motility, density, and histopathology of testicular tissue were evaluated. Material and Methods: In the experiment, 4 groups were formed, with eight animals (n=8) in each group. Group 1, control/saline, groups 2, 3, and 4 were administered orally sodium fluoride (NaF) at doses of 25, 50, and 100 ppm, respectively, for 30 days. Then the rats were sacrificed and testicular tissue samples were evaluated by sperm examination and histopathologically. Biochemical parameters malondialdehyde (MDA), catalase (CAT), advanced oxidation, and protein products (AOPP) were measured spectrometrically. Thiol/disulphide homeostasis was studied with a fully automated analysis method. Results: NaF exposure increased MDA and AOPP levels and decreased CAT levels. Disrupted thiol/disulphide homeostasis. Histopathological examination revealed integrity between germinal cells and tubular atrophy. NaF showed reduced sperm motility and density and increased abnormal sperm count. The findings of the NaF 100 ppm group were statistically significant when compared with the Control and other NaF groups (p˂0.05). Conclusion: The findings concluded that fluoride might cause pathological conditions and infertility in testicular tissue.

Corrosion of copper nickel titanium archwire in chlorhexidine, sodium fluoride, and chitosan mouthwashes

Background: Copper (Cu), nickel (Ni), chromium (Cr) ion release, and surface topography change from the orthodontic wire are the initial processes of corrosion that may affect the mechanical properties of the archwire. In this study, we aim to evaluate the effect of CHX, NaF, and chitosan on the corrosion of CuNiTi wire nickel and copper ions released, surface roughness change, and archwire deflection. Methods: Ninety samples of CuNiTi Tanzo™ archwires were divided into five groups according to their immersion solution: Artificial Saliva, CHX, NaF, CHX-NaF, and chitosan group. Each group was further divided into three subgroups (n=6) corresponding immersion time, i.e., two, four, and six weeks. The corrosion of the samples was analyzed with an atomic absorption spectrophotometer (AAS), scanning electron microscope (SEM), and universal testing machine (UTM). Results: The amount of nickel ion releases was increasing, but the copper ion releases were reduced by the time of observations. The highest nickel ion was released in the CHX-NaF group and the lowest in the chitosan group for six-week immersion. It also corresponded to the surface topography by SEM analysis which showed the most extended cracks and deep pits in the CHX-NaF group and a smoother surface in the chitosan group. Copper ion release showed the highest ion release in the NaF group and the lowest release in the chitosan group. The unloading force of CuNiTi archwire deflection remains the same at week two and week four for all mouthwashes. Conclusion: The use of mouthwashes that contained CHX, NaF, and chitosan could further alter the passive layer and cause higher nickel and copper ion release and increased CuNiTi archwire surface structure porosity. But there is no distinction between mouthwashes to release the unloading force within two until four weeks.

Effect of topical fluoride applications on residual monomer release from resin-based restorative materials

BackgroundThe effects of topical fluoride applications on the release of monomer ingredients from resin-based dental materials by immersion in various extraction solutions are unclear. The aim of this study was to determine the effect of topical fluorides (APF and NaF) on the elution of residual monomers (Bis-GMA, TEGDMA, UDMA, and HEMA) from resin-based materials.MethodsNinety specimens were prepared, 30 bulk-fill composite resin, 30 nanohybrid universal composite resin, and 30 polyacid-modified composite resin (compomer). These were randomly divided into three groups based on fluoride application procedures. Each specimen was kept in 75% ethanol solution, and residual monomers released from materials were analyzed using high-performance liquid chromatography (HPLC) after 10 min, 1 h, 24 h, and 30 days. The groups were compared using the Mann Whitney U and Kruskal Wallis tests. Measurements were analyzed using the Friedman and Wilcoxon signed-rank tests.ResultsFluoride applications generally had no considerable effect on the amount of residual monomer released from resin-based restorative materials. The amount of monomer release after topical APF application was similar to the release in the control group and was lower than the release in the NaF group. The release of monomers from the resin-based material used in the study did not approach toxic levels at the applied time intervals. The compomer released lower amounts of monomer than other resin-based materials.ConclusionsFluoride applications do not increase monomer release from resin-based restorative materials. However, compomers should be employed by clinicians due to their lower monomer release compared to other resin restorative materials. The release of monomers from all the resin-based materials did not approach toxic levels at the applied time intervals.

In-vitro effect of a single application of CPP-ACP pastes and different fluoridated solutions on the prevention of dental caries around orthodontic brackets.

To assess the in-vitro effect of single applications of CPP-ACP pastes and different fluoridated solutions on the prevention of dental caries around orthodontic brackets. Tooth/bracket sets (n=65) were immersed in artificial saliva (1h at 37ºC) and randomly subjected to single applications (100µL; 1min) of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP emulsion), CPP-ACP with fluoride (CPP-ACPF emulsion), solutions of titanium tetrafluoride (TiF4) or sodium fluoride (NaF), or no treatment (CG). Multispecies biofilm (5 x 105 CFU/mL) was formed in the presence of 2% sucrose. After 24 h, the pH and the concentration of total soluble fluoride (TSF) were analyzed by culture medium. The presence of active white spot lesions (WSL) evaluated by macroscopic examination and the percent surface mineral loss (%SML) were analyzed. Also, the topography of enamel was detected by analysis of scanning electron microscopy (SEM). The data was assessed by chi-square, Kruskal-Wallis, and Mann-Whitney tests (p < 0.05). Fluoride-containing compounds led to a smaller pH reduction than did CPP-ACP and CG (p<0.05). There was difference in TSF between the groups (p<0.05), denoted as TiF4> NaF > CPP-ACPF > CPP-ACP > CG. Regarding the presence of WSL and %SML, the NaF group obtained lower values (p<0.05), while TiF4 and CPP-ACPF were similar (p>0.05). SEM demonstrated that fluoride-free groups had a larger surface dissolution. Fluoridated groups including solutions and CPP-ACPF were more effective than CPP-ACP in reducing enamel demineralization around orthodontic brackets after a single application.

Synbiotic-fluoride synergism on enamel remineralization, cytotoxicity and genotoxicity

Objective(s)The objectives of the present study were to examine the – a) enamel remineralization potential of synbiotic-fluoride (SF) therapy using a multi-species bacterial pH-cycling model; and b) cytotoxic and genotoxic effects of SF therapy extracts. Materials and methodsThe SF therapy group comprised of 2% arginine (Arg), 0.2% NaF, and a probiotic Lactobacillus rhamnosus GG (LRG). The intervention groups studied were: 1) No treatment; 2) 2% Arg; 3) 0.2% NaF; 4) LRG; 5) 2% Arg+0.2% NaF; 6) 2% Arg+LRG; 7) 0.2% NaF+LRG; and 8) 2% Arg+0.2% NaF+LRG (SF therapy). The enamel remineralization potential of SF therapy was investigated under cariogenic biofilm challenge; while the cytotoxicity and genotoxicity of SF therapy extracts were examined on HGF-1 and Chinese hamster fibroblast V79, respectively. To determine the remineralization effect, the specimens were subjected to mineral density (MD) assessment using micro-CT, Ca/P molar ratio with SEM-EDX, and enamel fluoride uptake (EFU) estimates. The HGF-1 proliferation assessment was quantified using MTT/CCK-8 assays with qualitative analysis by nuclei staining Hoechst-based fluorescence imaging. The genotoxicity was determined by micronuclei formation test. ResultsMineral gain and %remineralization derived from MD assessment for the SF therapy were significantly higher than the other groups (p<0.05). The %ΔCa/P for the SF and 2% Arg+0.2% NaF were significantly higher than the other groups (p<0.05). The SF and 2% Arg+0.2% NaF groups had the highest EFU compared to the other groups (p<0.05). No significant difference in the %viable HGF-1 cells were observed between the treatment interventions and no treatment group (p>0.05). Compared to the EMS-positive control, the micronuclei formation for all the intervention groups was significantly lower (p<0.05), with no significant difference among the treatment groups (p>0.05). ConclusionThe SF therapy enhanced enamel remineralization with no biocompatibility concerns. Clinical significanceWith the enhanced enamel remineralization potential discerned in the present study, the SF therapy can be used as a promising caries-preventive agent targeted for high caries-risk individuals.

Choline alleviated perinatal fluoride exposure-induced learning and memory impairment through α4β2 nAChRs and α7 nAChRs in offspring mice.

Fluoride pollution is widely present in the living environment. As a critical period of brain development, the perinatal period is extremely vulnerable to fluoride. Studies have found that choline can protect the brain's memory and enhance the ability to focus. However, the effect of choline on perinatal fluoride-induced nerve damage remains unclear. Therefore, 32 Kunming newly conceived female mice and their offspring mice were randomly divided into control, NaF, LC + NaF, and HC + NaF groups, and the HE staining, Y-maze test, RT-PCR, western blotting, immunohistochemistry, etc. were used in this study. The results showed that fluoride decreased the brain organ coefficients and brain protein content (p < 0.05, p < 0.01), and caused histomorphological damage in the hippocampus and cortex, which suggested that fluoride affected the development of the brain and damaged the brain. Moreover, the results of the Y-maze test showed that fluoride increased the number of learning days, error reaction time, and total reaction time, and decreased the AchE activity in the brain (p < 0.05, p < 0.01), which indicated that fluoride reduced the learning and memory ability of the mice. Besides, the results showed that fluoride decreased the mRNA and protein expression levels of α4β2 nAChRs and α7 nAChRs in the hippocampus and cortex (p < 0.05, p < 0.01). However, perinatal choline supplementation reversed the aforementioned fluoride-induced changes. In short, these results demonstrated that choline alleviated perinatal fluoride-induced learning and memory impairment, which will provide a rationale for the mitigation and prevention of fluoride-induced brain damage.

Morphological, ultrastructural, and biochemical changes induced by sodium fluoride in the tongue of adult male albino rat and the ameliorative effect of resveratrol.

Little knowledge is available about the effects of fluoride exposure on the tongue. This study evaluated the effects of sodium fluoride (NaF) on the tongue ultrastructure and detected the ameliorative effects of resveratrol. Forty adult albino rats were separated into 4 groups: the control group was given a balanced diet and purified water. The NaF treated group: received 10 mg/kg/d dissolved in 2.5 ml distilled water once daily for 30 days orally. The NaF+resveratrol group: received NaF 10 mg/kg/d orally together with resveratrol in a dose of 30 mg/kg daily for 30 days. The resveratrol group was subjected to resveratrol in a dose of 30 mg/kg/d by oral gavage for 30 days. Sections were stained with hematoxylin & eosin, and Masson's trichrome. Tumor necrosis factor α immunohistochemical study and electron microscopic examinations were done. The oxidative stress markers malondialdehyde, antioxidant reduced glutathione, and the total antioxidant capacity were measured. The NaF group revealed ulceration, necrotic muscle fibers, distorted papillae and a significant increase in malondialdehyde level, and a significant decrease in glutathione and the total antioxidant levels. In the NaF+resveratrol group, pathological changes were less, and the oxidant levels were decreased by the administration of resveratrol with NaF. In conclusion, NaF adversely affects the ultrastructure of the adult rat tongue and resveratrol can ameliorate this effect.

Effect of chitosan application on lung tissue in rats with experimental fluorine toxicity

Aim: The aim of this study is to investigate the effects of chitosan application on lung tissue in rats with experimental fluorine toxicity.&#x0D; Material and Method: In the study, 21 healthy male wistar albino rats were used. Prior to the trial, the acclimation of the rats was provided. 3 groups were randomly generated in a way that there were 7 rats in each group. These were determined as the control group (C), the fluorosis group (NaF) and the fluorosis + chitosan (NaF+CS) group.&#x0D; Results: In the NaF group, CAT, SOD and GSH values were found to be low compared to other groups and MDA values were found to be high. It was found that the chitosan application reduced the CAT, SOD and GSH values, and increased the MDA value. &#x0D; Conclusion: It has been predicted that chitosan application may be beneficial in preventing cellular damage that may occur with fluorine exposure.

Comparison of Remineralization Effect of Casein Phosphopeptide Amorphous Calcium Phosphate and Sodium Fluoride on Enamel Surface after Orthodontic Debonding: An In vitro study

OBJECTIVE: To compare the result of "casein phosphopeptide amorphous calcium phosphate" with "sodium fluoride" (900 ppm) in remineralization of enamel after orthodontic debonding. METHODOLOY: This study was performed on premolars. Teeth were distributed into 3 groups A, B and C. The baseline microhardness of samples was measured. To create artificial demineralization, all samples were dipped in demineralizing solution. Surface microhardness (SMH) was re-measured for demineralization. Then, CPP-ACP was applied on teeth of gp B and NaF (900 ppm) was applied on teeth of gp C for remineralization. All teeth were cycled between deionized water and surface treatment for 12 weeks. The SMH of gp B and gp C was re-measured for remineralization. Paired t-test and Independent t-test were practiced to match MH before and after demineralization while keeping P value &lt; 0.05. One way ANOVA was practiced to match mean difference in baseline MH and after demineralization. RESULTS: The baseline SMH of enamel decrease after demineralization. After application of test materials, mean SMH increased by 230.2 VHN and 207.5 VHN respectively. The %age of SMHR reveal the recovery rate of 41.2% in CPP-ACP and 19.1% in NaF group. CONCLUSION: For treating post orthodontic demineralized lesions, a remineralizing cream having casein phosphopeptide stabilized amorphous calcium phosphate is useful with some mineral and aesthetic improvements. KEYWORDS: Casein Phosphopeptide Amorphous Calcium Phosphate (CPP-ACP), Sodium Fluoride (NaF), Surface Microhardness (SMH), Vickers Hardness Number (VHN), Rmineralization.

Effects of Two Fluoride Mouthwashes on Surface Topography and Frictional Resistance of Orthodontic Wires.

Objectives: This study compared the effects of fluoride mouthwashes on surface topography of orthodontic wires, and static and kinetic frictional forces between the stainless steel (SS) orthodontic brackets and SS and nickel-titanium (NiTi) archwires. Materials and Methods: This in vitro, study evaluated 240 standard SS maxillary central incisor brackets and 0.018, and 0.025×0.019 inch NiTi and SS archwires. The wire-bracket sets (different combinations of wire diameters and types) were exposed to artificial saliva (control), 0.05% sodium fluoride (NaF) for 1 minute daily, or 0.2% NaF for 1 minute, weekly (37°C) for 3 months. The wires were pulled in bracket slots by 5 mm in a universal testing machine (10 mm/minute). The static and kinetic forces were measured. The surface topography of wires was inspected under a scanning electron microscope (SEM; x500). Data were analyzed by SPSS 25. Results: The mean static and kinetic frictional forces of 0.025×0.019 inch NiTi wire in 0.05% NaF group were significantly greater than SS wire (P=0.000). The mean kinetic frictional force in 0.05% NaF was significantly greater than 0.2% NaF and artificial saliva for all wires (P=0.001). The mean static and kinetic forces in 0.2% NaF were significantly greater than in artificial saliva (P=0.025). In all groups, larger wires showed higher mean frictional forces (P=0.000). SEM results revealed higher wire surface roughness in 0.05% NaF followed by 0.2% NaF group. Conclusion: Weekly use of 0.2% NaF mouthwash is recommended during sliding mechanics to minimize frictional forces between the SS and NiTi wires and SS brackets.

Luteolin normalizes blood pressure via its antioxidant activity and down-regulation of renal Angiotensin II receptor and Mineralocorticoid receptor expressions in rats co-exposed to Diclofenac and sodium fluoride.

This study was designed to investigate the modulatory role of Luteolin (Lut), a flavonoid phytochemical, on haemodynamic parameters and the potential mechanisms involving renal Angiotensin II (AT2R) and Mineralocorticoid (MCR) receptors in renal toxicity induced by co-exposure to Diclofenac (Dcf) and sodium fluoride (NaF) in rats.Male Wistar rats were administered with either vehicle (control), Dcf only (9 mg/kg orally) or concurrently with NaF (300 ppm in drinking water). Other groups were treated with LutA (100 mg/kg) or LutB (200 mg/kg) along with Dcf and NaF exposures. All treatments lasted 8 days, following which blood pressure indices were measured using tail-cuff plethysmography. Renal expressions of AT2R and MCR were studied with immunohistochemistry, while biomarkers of oxidative and antioxidant status were also measured in the kidneys. Systolic, diastolic and mean arterial pressures were significantly (p<0.05) reduced in Dcf-treated rats, compared to control values. However, co-treatment with NaF or Lut restored these parameters. While the expression of AT2R and MCR was high in the Dcf and Dcf+NaF groups, treatment with Lut caused obvious reduction in the renal expression of these receptors. Increased lipid peroxidation (Malondialdehyde) and protein oxidation (protein carbonyls) with a lowering of reduced glutathione levels contributed to the renal toxicity of Dcf, and these were significantly ameliorated in Lut-treated rats. In conclusion, the preservation of haemodynamic indices by Lutin the experimental ratsprobably included mechanisms involving down-regulation of renal expressions of AT2R and MCR, reduction of oxidative stress and an improvement of renal antioxidant status.

Effect of Silver Diamine Fluoride and Potassium Iodide Solution on Enamel Remineralization and Discoloration in Artificial Caries.

Silver diamine fluoride (SDF) is a strong fluoride agent for caries control, remineralization, and reducing the incidence of dental caries. This study used 38% SDF with potassium iodide (KI) on enamel remineralization and compared it with the currently used 38% SDF and 5% sodium fluoride (NaF) varnish to treat artificial caries. Bovine incisors were demineralized for 120 h and randomly distributed for treatment by the remineralization agents for 120 h as follows: control (n = 15), SDF/KI (n = 15), SDF (n = 15), and NaF (n = 15). Colorimetric analysis was performed using the ΔE value. The Vickers microhardness (VHN) was determined to evaluate the enamel remineralization of the specimens. Polarized light microscopy (PLM) and scanning electron microscopy (SEM) were performed to confirm the surfaces precisely and histologically. SDF/KI caused no significant difference in discoloration between the control and NaF groups. There was also no significant difference in the VHN after remineralization, but SDF/KI exhibited the highest mean microhardness. PLM revealed that SDF/KI had the greatest remineralization ability. In conclusion, SDF/KI is effective for dental enamel remineralization even with KI, which reduces discoloration.