NaF Group Research Articles

In vitro study of the treatment of dentin hypersensitivity with gallic acid combined with sodium fluoride

BackgroundDentin hypersensitivity (DH) is a common oral condition that is associated with severe dental pain. Pain relief is a key focus of the treatment of DH. The purpose of this study was to evaluate the blocking and antacid effects of gallic acid (GA) combined with sodium fluoride (NaF) on dentinal tubules in vitro.MethodsNinety dentin discs from human third molars were treated with 6% citric acid for 2 min. Then, the surface morphologies of ten dentin discs were observed by scanning electron microscopy (SEM). The remaining samples were randomly divided into four groups: the NaF group, which was treated with 1000 ppm NaF; the GA group, which was treated with 4000 ppm GA; the GA + NaF group, which was treated with 1000 ppm NaF + 4000 ppm GA; and the blank group, which was treated with deionized water. The dentin permeability of each sample was measured with a water-filled system before processing and after 7 days of treatment. Dentin morphology and surface deposits were observed by SEM. Then, samples from the NaF, GA + NaF and blank groups were subjected to an acid challenge by incubation with 0.02% citric acid for 2 min. SEM and a water-filled system were used to evaluate the blocking and antacid effects of NaF and GA + NaF.Results1. NaF and GA + NaF significantly decreased dentin permeability. The effect of the GA + NaF treatment was more significant. After acid challenge, both groups still exhibited decreased dentin permeability compared with the initial assessment. 2. Compared with the NaF group, the GA + NaF group had more mineral deposits on the dentin surface and dentin tubules. After acid challenge, the deposits in the GA + NaF group were still clearly visible.ConclusionThe combined effect of GA and NaF on reducing dentin permeability by blocking open dentin tubules is better than that of NaF alone. After acid challenge, the GA + NaF treatment still had a better effect.

Naringin alleviates fluoride-induced neurological impairment: A focus on the regulation of energy metabolism mediated by mitochondrial permeability transition pore

The neurological impairment induced by fluoride is associated with mitochondrial dysfunction. Normal mitochondrial permeability transition pore (mPTP) opening plays a pivotal role in mitochondrial function. However, it remains unclear whether p53-dependent mPTP-related mitochondrial apoptosis is associated with fluoride-induced neurological impairment, and the alleviation of naringin on those. In vivo, NaF-treated rats had impaired learning and memory abilities, damaged hippocampal structure, and higher respiratory exchange rates (RER). In vitro, the increased apoptosis rates, excessive opening of mPTP, and decreased mitochondrial membrane potential (MMP) were observed in PC12 cells treated with NaF. The protein expressions of p53, CytoC, and cleaved caspase 3 were significantly increased in hippocampi of rats treated with 50 mg/L and 100 mg/L NaF and in 40 mg/L and 80 mg/L NaF-treated PC12 cells, while the protein expression of CypD remains stable. And the changes of p53 and CypD were also confirmed by the immunofluorescence staining in vivo. After inhibiting the expression of p53 with pifithrin-α and p53-siRNA, the decreased apoptosis rates and mPTP opening, increased MMP, and decreased protein expressions of p53, CytoC, and cleaved caspase 3 were observed in NaF-treated PC12 cells. Rats, treated with NaF and naringin, had alleviated impaired neurological function, and had lower RER than rats treated with NaF alone. And compared with those in the NaF group, the decreased apoptosis rates and mPTP opening, and increased MMP were also found in PC12 cells treated with NaF and naringin. Furthermore, hippocampi of rats and PC12 cells treated with NaF and naringin had decreased protein expressions of p53, CytoC, and cleaved caspase 3. Our results indicate that fluoride activates the p53-dependent mPTP-related mitochondrial apoptosis, which then affects energy metabolism, resulting in neurological impairment. Additionally, naringin can alleviate this damage, and further studies on the potential health benefits of naringin are needed.

Sodium Fluoride Exposure Induces Developmental Toxicity and Cardiotoxicity in Zebrafish Embryos.

Fluorosis is a worldwide public health problem, in which the heart is an important target organ. However, studies on its toxicological mechanism in embryonic development are limited. This study assessed the toxicity of sodium fluoride (NaF) toward zebrafish embryos. We determined the mortality, hatching rate, phenotypic malformation, heart function, and morphology of zebrafish embryos after exposure to NaF. Subsequently, the molecular mechanism was revealed using high-throughput RNA sequencing analysis. The expression levels of key genes for heart development were detected using quantitative real-time reverse transcription PCR. The 50% lethal concentration (LC50) value of NaF toward zebrafish embryos at 96h post-fertilization was 335.75mg/L. When the concentration of NaF was higher than 200mg/L, severe deformities, such as pericardial edema, yolk sac edema, spine curvature, shortened body length, reduced head area, and eye area, were observed. The heart rate of the embryos exposed to NaF decreased in a dose-dependent fashion. The distance between the sinus venosus and bulbus arteriosus was significantly increased in the NaF-exposed group compared with that in the control group. The stroke volume and cardiac output decreased significantly in the NaF groups. Compared with the control group, the expression levels of Gata4, Tbx5a, Hand2, Tnnt2c, Nppa, and Myh6 were significantly increased in the NaF-treated group. Through transcriptome sequencing, 1354 differentially expressed genes (DEGs) were detected in the NaF (200mg/L) treated groups, including 1253 upregulated genes and 101 downregulated genes. Gene ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway analyses of the DEGs showed that cardiac-related pathways, such as actin cytoskeleton regulation, Jak-Stat, PI3k-Akt, and Ras, were activated in the NaF-exposed group. This study revealed the underlying mechanism of fluoride-induced cardiac morphological and functional abnormalities and provides clues for the clinical prevention and treatment of fluorosis.

Effectiveness of topical 25% silver nitrate solution followed by 5% fluoride varnish compared to 38% silver diamine fluoride in arresting and preventing dental caries among beta-thalassemia major patients: A randomized clinical trial

IntroductionThis is the first randomized non-inferiority clinical trial in the evidence literature to examine the effectiveness of topical 25% silver nitrate (SN) followed by 5% sodium fluoride (NaF) varnish is not much worse or acceptable to 38% silver diamine fluoride (SDF) in preventing and arresting dental caries among Beta-Thalassemia Major (BTM) patients. Method170 BTM participants aged 18 years and older with at least 1 or more active carious lesions were randomly allocated into 2 groups (1:1). 25% silver nitrate solution application followed by 5% NaF varnish was administered to Group I, and Group II received 38% SDF. The Nyvad criteria and DMFT index were used to assess caries arrest and prevention among both groups at 3- and 6-months interval. ResultsCaries arrest rate at 3 months was significantly higher in Group I (83.10%) when compared to Group II (76.16%) (p<0.05). While at 6 months, both the groups were comparable with arrest rate (76.16%) (p>0.05). The caries increment was comparable among both groups at 3 months, while at 6 months, caries increment was almost half in SN with NaF group compared to SDF group (p>0.05). Kaplan–Meir survival estimated the median survival time for caries increment was 17 and 39 weeks for Group I and 15 and 36 weeks for Group II at 3 and 6 months, respectively. ConclusionOne time application of 25% SN followed by 5% NaF is no worse than a 38% SDF in arresting and preventing dental caries among Thalassemia Major participants at 3 and 6 months. Clinical SignificanceThe study provides clinicians with a cost-effective, safer, readily available, non-invasive treatment option (25% SN followed by 5% NaF) for caries management.

Remineralizing effect of NSF on artificial enamel caries

IntroductionNanotechnology offers new approaches and endless opportunities for remineralizing tooth decay without being toxic or causing allergies. This study aimed to determine the effect of nanosilver fluoride (NSF) on the remineralization potential of enamel caries-like lesions compared to 5% sodium fluoride varnish in permanent teeth.MethodsFifteen teeth (molars and premolars) were gathered, cleaned, and polished using a scaler. After sectioning the teeth mesiodistally and removing the roots, the thirty specimens were subjected to a demineralized solution to induce early enamel lesions and then assigned randomly into two equal groups. The test materials were applied, and then all the specimens were subjected to a pH cycling model for 30 days. DIAGNOdent and surface roughness were investigated, and an evaluation of the enamel Ca and P weight% for Ca/P ratio calculation was done using SEM-EDX to analyze the specimens at the end of the study. The data were analyzed using an independent t-test.ResultsThe mean values for the DIAGNOdent measurements for NSF and NaF at baseline and after demineralization were not significantly different (p > 0.05). After treatment, NaF varnish showed a significantly higher mean DIAGNOdent measurement (11.8 ± 5.80) than NSF (4.7 ± 1.6). The mean surface roughness of the NaF group (1.64 ± 0.39) was much higher than NSF’s mean surface roughness (1.07 ± 0.21). Specimens treated with NSF had statistically significant smoother surfaces (p < 0.001). The NSF group had a higher mean Ca/P ratio (2.9 ± 0.35) than NaF (2.2 ± 0.11). This difference was statistically significant (p = 0.012).ConclusionThe study reveals that nano silver fluoride is a more effective treatment than sodium fluoride varnish in enhancing teeth’s clinical characteristics, particularly in terms of mineral content and surface roughness, suggesting it could be an improved strategy to prevent dental caries and maintain enamel integrity.

In vitro assessment of NaF/Chit supramolecular complex: Colloidal stability, antibacterial activity and enamel protection against S. mutans biofilm

ObjectivesThis study assessed the effect of NaF/Chit suspensions on enamel and on S. mutans biofilm, simulating application of a mouthrinse. MethodsThe NaF/Chit particle suspensions were prepared at molar ratio [NaF]/Chitmon]≈0.68 at nominal concentrations of 0.2 % and 0.05 % NaF and characterized by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering and zeta potential. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured. The S. mutans biofilm was formed for 7 days on eighty human enamel blocks that were divided into eight groups (n = 10/group): i) 0.05 % NaF solution; ii) 0.31 % Chit solution; iii) NaF/Chit(R=0.68) suspension at 0.05 % NaF; iv) 1.0 % HAc solution (Control); v) 0.2 % NaF solution; vi) 1.25 % Chit solution; vii) NaF/Chit(R=0.68) suspension at 0.2 % NaF; viii) 0.12 % chlorhexidine digluconate. The substances were applied daily for 90 s. S. mutans cell counts (CFU/mL) were performed, and the Knoop microhardness (KHN) of enamel samples were measured before and after biofilm formation. The KHN and CFU/mL data were analyzed by repeated measure ANOVA and Tukey's test (α = 0.05). ResultsInteractions between NaF and Chit were evidenced in solid state by FTIR spectra. The NaF/Chit complexes showed spontaneous microparticle formation and colloidal stability. The MIC and MBC ranged from 0.65 to 1.31 mg/mL. The NaF/Chit(R=0.68) suspension at 0.2 %NaF Group showed lower CFU/mL values than other groups. The NaF/Chit(R=0.68) suspensions Groups had the highest KHN values after biofilm formation. ConclusionsThe NaF/Chit(R=0.68) complexes exhibited an antibacterial effect against S. mutans biofilm and reduced the enamel hardness loss. Clinical significanceThe NaF/Chit(R=0.68) suspensions showed potential to be used as a mouthrinse for caries prevention.

Effects of Lasers and Fluoride Varnish on Microhardness and Calcium and Phosphorus Content of Demineralized Enamel.

Objectives: This study assessed the effects of blue and Er:YAG lasers, fluoride varnish, and their combination on microhardness, and calcium and phosphorus content of demineralized enamel. Materials and Methods: The primary Vickers microhardness of 28 third molars was measured and their enamel calcium and phosphorous content was quantified by energy-dispersive X-ray spectroscopy. They were then randomly assigned to five groups of 5% sodium fluoride (NaF) varnish, 445nm blue laser, Er:YAG laser, 5% NaF + 445nm blue laser, and 5% NaF + Er:YAG laser. The teeth then underwent pH-cycling to induce caries-like lesions. The surface microhardness of the teeth and the calcium and phosphorous content of demineralized enamel were measured again. Data were analyzed by one-way ANOVA and Tukey's test (alpha=0.05). Results: NaF, NaF-diode laser, and NaF-Er:YAG laser groups experienced a significant increase in microhardness of demineralized enamel close to the baseline value (P<0.05). The efficacy of NaF-blue laser and NaF-Er:YAG laser was higher than NaF . In blue and Er:YAG laser groups, the mean final microhardness was significantly lower than the baseline microhardness. The percentage of phosphorus in all groups was similar to that of sound enamel. The percentage of calcium in NaF group was significantly lower than that of sound enamel and all other groups. The calcium content in other groups was similar to that of sound enamel. Conclusion: Fluoride varnish had a synergistic effect with Er:YAG and blue lasers to increase the demineralized enamel microhardness; blue and Er:YAG lasers alone were less effective.

Efficacy of silver diamine fluoride on immediate and delayed adhesive strength of resin composite to sound dentin of permanent teeth: an in vitro study

Objectives: How silver diamine fluoride affected the immediate and prolonged adhesive resin composite's resistance to sound dentin of permanent premolars. Procedures: Three groups were identified (total number=30). The manufacturer's recommendations were followed while applying adhesive resin to the dentin surfaces in Group A after they had been etched. In Group B and C, dentin surfaces were treated with silver diamine fluoride and 0.05% NaF respectively. Then etched and bonded as for the control group. Then resin composite build-ups were created. Following this, each group was divided into two subgroups (for each group n=5), subgroup 1 underwent a shear bond strength test by universal test machine after 24 hrs, subgroups 2 the test was done after thermocycling process (300 cycles). The mode of failure was also examined. Results: The type of dentin surface treated with SDF solution was significantly affect shear bond strength (p=0.000) for both periods (immediate and prolonged). However, there were no significant difference between NaF group and control group on shear bond strength (p&lt;0.05) in immediate and prolong periods. On other hand there were statistically no significant differences between immediate and prolonged shear bond strength in SDF group (p=0.850), NaF group (p=0.637) and control group(p=0.794) When dentin surfaces were treated with silver diamine fluoride , there were more adhesive failures not as 0.05% NaF and control group which showed more mixed failures. Conclusion: silver diamine fluoride significantly reduced bond strength of etch and rinse adhesive system. Pretreatment with NaF maintained the shear bond strength of the adhesive to dentin after 300 thermal cycles.

Luteolin Ameliorates Non-alcoholic Fatty Liver Disease via Regulation of Hepatic Lipid Uptake, Autophagy, and Apoptosis in WD/CCl4-induced Mice

Background and Purpose Nonalcoholic fatty liver disease (NAFLD) is a worldwide health problem with high prevalence and morbidity associated with obesity, insulin resistance, type 2 diabetes mellitus (T2DM), and dyslipidemia. Luteolin is a natural flavonoid with various activities. We aimed to investigate whether luteolin can alleviate NAFLD and its possible mechanism. Materials and Methods A mouse model with NAFLD was induced by Western diet (WD) and carbon tetrachloride (CCl4) injection. Twenty-four mice were distributed into three groups randomly: Normal diet group (CON, n = 8), NAFLD group (NAF, n = 8), and luteolin group (LUT, n = 8). NAFLD model was induced by feeding mice in NAF and LUT groups with WD and injecting CCl4. CON group were fed with a normal diet in the same period. The LUT group was administered orally with luteolin (20 mg/kg) every day, starting from the 1st day of the 5th week for 8 weeks, while the CON group was treated with a vehicle. Throughout the experiment, body weight, lipid profile, glucose tolerance test, and the hepatic expressions of CD36/FABP1/LC3B/Bcl-2 were measured beside the histopathological examination. Results Luteolin treatment effectively prevents the body from weight gain in mice with NAFLD (NAF vs. LUT: 36.0 g vs. 32.4 g, p &lt; 0.05). Serum total cholesterol and triglyceride levels are both significantly increased in the NAF group ( p &lt; 0.01) and reduced to some extent in the LUT group ( p &lt; 0.05). Oral glucose tolerance test (OGTT) test results show that luteolin could improve the impaired glucose tolerance and downregulate the elevated fasting blood glucose in mice with NAFLD ( p &lt; 0.05). Histopathological results demonstrate luteolin reduces hepatic steatosis and hepatic fibrosis in NAFLD mice. The possible mechanisms may include that luteolin decreases hepatic CD36 and FABP1 expression, and increases levels of autophagy marker LC3B and antiapoptotic protein Bcl-2. Conclusion Luteolin could reduce hepatic steatosis and fibrosis, hyperglycemia, body weight, and serum lipid levels in NAFLD mice, which exhibits huge potential in the treatment of metabolic disorders related to NAFLD.

Fluoride exposure during puberty induces testicular impairment via ER stress-triggered apoptosis in mice

Fluoride, a ubiquitous environmental compound, carries significant health risks at excessive levels. This study investigated the reproductive toxicity of fluoride exposure during puberty in mice, focusing on its impact on testicular development, spermatogenesis, and underlying mechanisms. The results showed that fluoride exposure during puberty impaired testicular structure, induced germ cell apoptosis, and reduced sperm counts in mice. Additionally, the SOD activity and GSH content were significantly decreased, while MDA content was significantly elevated in the NaF group. Immunohistochemistry showed an increase in the number of cells positive for GRP78, a key ER stress marker. Moreover, qRT-PCR and Western blot analyses confirmed the upregulation of both Grp78 mRNA and protein expression, as well as increased mRNA expression of other ER stress-associated genes (Grp94, chop, Atf6, Atf4, and Xbp1) and enhanced protein expression of phosphorylated PERK, IRE1α, eIF2α, JNK, XBP-1, ATF-6α, ATF-4, and CHOP. In conclusion, our findings demonstrate that fluoride exposure during puberty impairs testicular structure, induces germ cell apoptosis, and reduces sperm counts in mice. ER stress may participate in testicular cell apoptosis, and contribute to the testicular damage and decreased sperm counts induced by fluoride.

Clinical effect of chlorhexidine and sodium fluoride on corrosion behavior and surface topography of nitinol orthodontic archwires

BackgroundAlterations in the mechanical properties of the materials utilized in orthodontic appliances could affect the working properties of the appliances, thereby affecting clinical progress and outcome. Numerous studies have confirmed the correlation between alloy corrosion and raised surface roughness, which has a direct impact on the working characteristics of orthodontic archwires.MethodsThirty nickel-titanium (NiTi) orthodontic archwires were utilized in this study. Patients were randomly selected and allocated into three groups according to the randomization plan; (The control group): subjects practiced regular oral hygiene; (The fluoride group): subjects used fluoride for intensive prophylaxis; (The chlorhexidine group): subjects used chlorhexidine. Representative samples were evaluated by SEM, and then SEM images with high resolution were examined using Image J software to determine the surface roughness and obtain the results for further statistical analysis.ResultsOur findings indicated a significant difference was found between the three groups regarding the anterior and posterior parts between the control and the two other groups and a non-significant difference between NaF and CHX groups. Overall, the p-value for group comparisons was 0.000 for both parts, indicating a highly significant difference especially between the control and NaF groups.ConclusionMouthwashes containing sodium fluoride demonstrated more significant surface alterations than the control and CHX groups and should be prescribed in accordance with orthodontic materials to reduce side effects.

Bifidobacterium Relieved Fluoride-Induced Hepatic and Ileal Toxicity via Inflammatory Response and Bile Acid Transporters in Mice.

Fluoride is a pervasive environmental contaminant. Prolonged excessive fluoride intake can inflict severe damage on the liver and intestines. Previous 16S rDNA sequencing revealed a decrease in ileal Bifidobacterium abundance during fluoride-induced hepatointestinal injury. Hence, this work aimed to investigate the possible mitigating function of Bifidobacterium on hepatointestinal injury caused by fluoride. Thirty-six 6-week-old C57BL/6J mice (equally divided between males and females) were allotted randomly to three groups: Ctrl group (distilled water), NaF group, and NaF + Ba group (100 mg/L NaF distilled water). After 10 weeks, the mice were given 1 × 109 CFU/mL Bifidobacterium solution (0.2 mL/day) intragastrically in the NaF + Ba group for 8 weeks, and the mice in other groups were given the same amount of distilled water. Dental damage, bone fluoride content, blood routine, liver and intestinal microstructure and function, inflammatory factors, and regulatory cholic acid transporters were examined. Our results showed that fluoride increased glutamic-oxalacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT) activities, and the levels of lipopolysaccharide (LPS), IL-1β, IL-6, TNF-α, and IL-10 levels in serum, liver, and ileum. However, Bifidobacterium intervention alleviated fluoride-induced changes in the above indicators. In addition, Bifidobacterium reduced the mRNA expression levels of bile acid transporters ASBT, IBABP, OST-α, and OST-β in the ileum. In summary, Bifidobacterium supplementation relieved fluoride-induced hepatic and ileal toxicity via an inflammatory response and bile acid transporters in the liver and ileum of mice.

Enhancing the inhibition of dental erosion and abrasion with quercetin-encapsulated hollow mesoporous silica nanocomposites.

Introduction: Dental erosion and abrasion pose significant clinical challenges, often leading to exposed dentinal tubules and dentine demineralization. The aim of this study was to analyse the efficacy of quercetin-encapsulated hollow mesoporous silica nanocomposites (Q@HMSNs) on the prevention of dentine erosion and abrasion. Method: Q@HMSNs were synthesized, characterized, and evaluated for their biocompatibility. A total of 130 dentine specimens (2mm × 2mm × 2mm) were prepared and randomly distributed into 5 treatment groups (n = 26): DW (deionized water, negative control), NaF (12.3mg/mL sodium fluoride, positive control), Q (300μg/mL quercetin), HMSN (5.0mg/mL HMSNs), and Q@HMSN (5.0mg/mL Q@HMSNs). All groups were submitted to in vitro erosive (4 cycles/d) and abrasive (2 cycles/d) challenges for 7days. The specimens in the DW, NaF, and Q groups were immersed in the respective solutions for 2min, while treatment was performed for 30s in the HMSN and Q@HMSN groups. Subsequently, the specimens were subjected to additional daily erosion/abrasion cycles for another 7days. The effects of the materials on dentinal tubule occlusion and demineralized organic matrix (DOM) preservation were examined by scanning electron microscopy (SEM). The penetration depth of rhodamine B fluorescein into the etched dentine was assessed using confocal laser scanning microscopy (CLSM). The erosive dentine loss (EDL) and release of type I collagen telopeptide (ICTP) were measured. The data were analysed by one-way analysis of variance (ANOVA) with post hoc Tukey's test (α = 0.05). Results: Q@HMSNs were successfully synthesized and showed minimal toxicity to human dental pulp stem cells (HDPSCs) and gingival fibroblasts (HGFs). Q@HMSNs effectively occluded the dentinal tubules, resulting in a thicker DOM in the Q@HMSN group. The CLSM images showed more superficial penetration in the HMSN and Q@HMSN groups than in the quercetin, NaF, and DW groups. The Q@HMSN group exhibited a significantly lower EDL and reduced ICTP levels compared to the other groups (p < 0.05). Conclusion: Q@HMSNs hold promise for inhibiting dentine erosion and abrasion by promoting tubule occlusion and DOM preservation.

Remineralization potential of a novel varnish: an in vitro comparative evaluation.

Despite fluoride's widespread use in preventing dental caries, it remains a significant oral disease with some drawbacks. Consequently, new preventative agents have emerged that can function independently of fluoride. Our aim is to demonstrate the efficacy of newly developed varnishes, 3% Rennou (theobromine calcium and phosphate) and 1% Rennou, in remineralizing initial caries. In our experiment, 40 human enamel samples were randomly allocated into four groups of 10 samples each as: Group 1 (G1): 5% NaF (Colgate PreviDent®), Group 2 (G2): 1% Rennou®, Group 3 (G3): 3% Rennou® and Group 4 (G4): Casein Phosphopeptide-Amorphous Calcium Phosphate + Fluoride (MI VarnishTM GC). To produce an artificial carious lesion in the enamel, the samples were kept in a demineralizing solution for 72 hours. Samples underwent pH cycling for 6 days in order to induce remineralization. The means of the three measurements were compared, and the percentage of Surface Microhardness Recovery in (SMHR%) was calculated. Scanning Electron Microscopy (SEM) was used for qualitative assessment of surface changes. G1 had the highest SMHR% value, followed by G3, G2 and G4. The One-way ANOVA (Analysis of Variance) showed significant differences in the SMHR% values among the groups after six days of cycling (p < 0.001). In pairwise comparisons, groups did not show differences in means of SMHR% except for G1 and G4 (p = 0.006). In the SEM Images, after treatment within the NaF group, many flaky sediments were found on the enamel surface. Similarly, the maximum mineral gain was seen in the NaF and Rennou groups. SEM images of both varnish surfaces revealed a uniform layer interspersed with shapeless precipitates. All varnishes treated artificial enamel lesions to varying degrees. However, both concentrations of Rennou showed remineralization potential comparable to 5% NaF in acceptable statistical measurements. Thus, it could be used as a potentially effective preventive measure for pediatric patients.

Antibacterial, Antibiofilm, and Tooth Color Preservation Capacity of Magnesium Oxide Nanoparticles Varnish (in vitro Study).

Antibacterial and antibiofilm properties of magnesium oxide nanoparticles (MgONPs) mixture assessed against Streptococcus mutans (S. mutans), in addition to examining MgONPs varnish impact on the preservation of the tooth color and inhibition of methylene blue diffusion to the enamel. MgONPs mixture was prepared in deionized water (DW), absolute ethanol (E), and rosin with ethanol (RE), named varnish. The antibacterial and antibiofilm capacities of MgONPs mixtures were tested by agar well diffusion, colony-forming unit (CFU), and biofilm inhibition microtiter methods in triplicate and compared to sodium fluoride varnish (NaF) and chlorhexidine mouthwash (ChX). A spectrophotometer was used to record basic tooth color. The artificial demineralization was initiated for 96 h. Then, experimental materials were applied to the corresponding group, and 10-day pH cycles proceeded. Then, the color was recorded in the same ambient environment. The methylene blue diffusion was evaluated by staining the samples for 24 h. After that, the diffusion test was calculated by a digital camera attached to the stereomicroscope. The agar well diffusion test expressed a significant inhibition zone with all MgONPs mixtures (p = 0.000), and maximum inhibition zone diameter associated with MgONPs-RE. The same finding was observed in the CFU test. Additionally, 2.5%, 5%, and 10% MgONPs-RE varnish showed strong biofilm inhibition capacity (p = 0.039) compared to NaF and ChX groups that inhibit biofilm formation moderately (p = 0.003). The study shows that the 5% MgONPs-RE varnish maintains basic tooth color with minimal methylene blue diffusion compared to NaF varnish (p = 0.00). Evaluating MgONPs as a mixture revealed antibacterial and antibiofilm capacity against S. mutans with a higher effect of MgONPs-RE varnish. Also, examining the topical effect of MgONPs-RE varnish on the preservation of the tooth color after pH cycle challenges and methylene blue diffusion to enamel confirmed the high performance of MgONPs-RE varnish at 5%.

Nigella sativa oil restores hormonal levels, and endocrine signals among thyroid, ovarian, and uterine tissues of female Wistar rats following sodium fluoride toxicity

The current study aimed to explore the possible prophylactic and therapeutic effect of Nigella sativa L. oil (NSO) against disruption of endocrine signals and injuries in the thyroid gland, ovary, and uterine tissues induced by sodium fluoride (NaF). Twenty-eight mature female Wistar rats were randomly allocated into four experimental groups (n = 7/group) as follows: control group; NaF group, orally received NaF (20 mg/kg b.wt.) daily; NSO/NaF, orally received NSO (300 mg/kg b.wt.) two weeks before being given NaF and continued throughout the experiment; and NSO+NaF group orally received NSO concurrently with NaF. Our results indicated that NSO restored hormonal balance and suppressed oxidative damage and inflammation. Moreover, the levels of triiodothyronine, thyroxine, thyroid peroxidase, estrogen (E2), progesterone, follicle-stimulating hormone, and luteinizing hormone were elevated, while prostaglandins F2-α and cortisol levels were decreased in NSO treated groups compared to NaF-intoxicated rats. As well, NSO significantly boosted levels of antioxidant molecules, and lowered lipid peroxidation of examined tissues, unlike NaF-treated group. NSO also up-regulated antioxidant enzymes, anti-apoptotic protein, zona pellucida sperm-binding protein, bone morphogenetic protein, and thyroid stimulating hormone, conversely down-regulated inflammatory cytokines, apoptotic proteins, estrogen receptor-α, estrogen receptor-β, and thyroid stimulating hormone receptors compared to NaF-intoxicated group. Additionally, NSO ameliorated tissue damage of the thyroid gland, ovary, and uterus induced by NaF. -Overall, the prophylactic group (NSO/NaF) performed better antioxidant and anti-inflammatory activities than the treated group almost in all examined tissues, which is reflected by the improvement in the structure of the thyroid, ovarian, and uterine tissues.

Influence of surface pre-reacted glass-ionomer (S-PRG) filler eluate on collagen morphology, remineralization, and ultimate tensile strength of demineralized dentin

ObjectiveTo evaluate the effect of ions released from surface pre-reacted glass-ionomer (S-PRG) filler on collagen morphology, remineralization, and ultimate tensile strength (UTS) of demineralized dentin. Materials and methodsBovine incisor root dentins were demineralized with EDTA and divided into three treatment groups: 1) water (control); 2) S-PRG filler eluate; 3) 125 ppm sodium fluoride (NaF). After a 3-min treatment, the specimens were stored in simulated body fluid (SBF) for 3 months. Collagen morphology and remineralization were assessed using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). Additionally, ultimate tensile strength (UTS) was measured. ResultsTEM and SEM demonstrated that S-PRG induced more effective remineralization compared to NaF, while the control group exhibited faint mineral deposition with collagen degradation. S-PRG displayed the most homogenous mineral deposition in collagen fibrils, along with closure of interfibrillar spaces. Extensive mineral precipitation was observed within dentinal tubules in the S-PRG group. In addition, S-PRG filler eluate demonstrated significantly higher phosphate-to-amide ratio and UTS compared to NaF and control groups (p < 0.05). ConclusionsIon released from S-PRG filler positively influenced collagen morphology, remineralization, and ultimate tensile strength of demineralized dentin. Clinical significanceS-PRG filler enhances remineralization and improve the biomechanics of demineralized dentin.

The effect of silver nanoparticles in addition to sodium fluoride on remineralization of artificial root dentin caries.

Silver nanoparticle was developed to overcome the drawback of silver diamine fluoride. However, evidence is limited, especially in root caries. The aim of this study was to evaluate the remineralization effect of silver nanoparticles on root caries. Fifty-five root human dentin slices size 5 × 5 mm2 from patients aged over 60 years old were immersed in demineralized solution to create artificial caries. Specimens were allocated into five groups according to the remineralizing agents: silver diamine fluoride (SDF), silver nanoparticles solution (AgNPs), silver nanoparticle solution followed by sodium fluoride varnish (AgNPs+NaF), sodium fluoride varnish (NaF), and tap water. After 8 days of pH-cycling challenge, the microhardness test, lesion depth evaluation, dentin surface morphology, and elemental analysis were performed. Data was analysed using F-test One-way ANOVA followed by Tukey's post hoc test and paired T-test. All test groups demonstrated a significantly higher microhardness value and lower lesion depth compared with the control group. AgNPs+NaF and NaF-treated groups showed lower efficacy than SDF. Crystal precipitation was presented in all groups composed of silver. Addition of fluoride varnish did not benefit for silver nanoparticles in preventing further demineralization. SDF provides the highest effectiveness in elderly root carious dentin.

Enamel remineralization potential and antimicrobial effect of a fluoride varnish containing calcium strontium silicate.

ObjectivesTo investigate enamel remineralization and antimicrobial effect of sodium fluoride (NaF) varnish containing calcium strontium silicate (CSR). MethodsCSR was synthesized by sol-gel process and incorporated in 5 % NaF varnish at three different concentrations (1 %, 2 %, and 4 % w/v). The treatment/control groups were: 1 % CSR+NaF, 2 % CSR+NaF, 4 % CSR+NaF, NaF, and no treatment. Strontium and fluoride release from the varnishes was evaluated. Sound enamel specimens (n = 6) were demineralized, varnish-treated, and subjected to remineralization cycle. Mineral density of enamel specimens was evaluated using micro-CT. Antimicrobial effect of the varnishes on Streptococcus mutans and Lactobacillus acidophilus biofilms was assessed using confocal laser scanning microscopy. The HGF-1 cytotoxicity of the varnishes was examined using CCK-8 assay. ResultsBoth 2 % and 4 % CSR+NaF varnishes showed significantly higher F release and remineralization potential than NaF varnish (p < 0.05). Dead bacterial proportion of 4 % CSR+NaF varnish was significantly higher than NaF varnish (p < 0.05). The CFUs values of both S. mutans and L. acidophilus were significantly lower in 4 % CSR+NaF group than NaF group (p < 0.05). No significant difference in cell viability was observed among the groups (p > 0.05). ConclusionsIncorporation of 4 % CSR in a NaF varnish significantly enhanced its enamel remineralization and antimicrobial potential with no cytotoxic effect. Clinical significanceDental caries is a major public health problem globally. The study highlights the great potential of CSR-doped NaF varnish as a novel anti-caries agent with synergistic remineralizing and antimicrobial properties to combat early enamel caries lesions in the general population.

Comparative Evaluation on the Effect of Different Remineralizing Agents on Enamel-Bracket Shear Bond Strength: An In Vitro Study.

This study aimed to compare the effects of applying various remineralizing agents before and after acid etching on the enamel-bracket shear bond strength (SBS) in vitro. These agents included silver diamine fluoride (SDF), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and 5% sodium fluoride (5% NaF). All the selected teeth were divided equally into six subgroups depending on before and after acid etching and one separate control group for the in vitro study design. Eighty-four extracted premolar teeth (12 teeth in each group x seven groups, including the control group). Before acid etching, teeth in groups A1, B1, and C1 were given SDF, CPP-ACP paste, and 5% NaF, respectively. Following acid etching, all of the teeth in Groups A2, B2, and C2 received the same preventative treatments. After that, the SBSof the bonded brackets to the enamel was evaluated. The CPP-ACP group, control group, and SDF group had the highest values for SBS prior to acid etching.The 5% NaF group had the weakest bonds, and the difference between the groups was statistically significant. The CPP-ACP group had the highest SBS following acid etching, followed by the 5% NaF group. The least bond strength was seen in the SDF group, and the difference between the three groups was significant. When it comes to bonding orthodontic brackets, the CPP-ACP pretreatment is superior to fluoride pretreatment in terms of effectiveness. The use of these remineralizing agents resulted in favorable values that did not have any effect on the SBS and were therefore safe to use with orthodontic brackets.