Ppm Fluoride Research Articles

Optimization studies for water defluoridation with two-stage coagulation processes using new industrial-based chemical coagulants

The fluoride removal capability of a new industrial-based chemical coagulant (Formula A) in one- and two-stage coagulation treatments was investigated in present study. Three main controlling factors, the coagulant concentration, reaction time and the initial pH of Formula A were studied on the fluoride removal accordingly, with the aid of other coagulants: Ecogent F-Loc, potassium ferrate (K2FeO4), and sodium aluminate (NaAlO2). Response surface methodology (RSM) was adopted to analyse the controlling factors on the fluoride removal efficiency (R%) using Box-Behnken designs (BBD). The coagulant concentration of Formula A shows the most significant effect on R% and better fluoride removal capability at an initial pH 12. Nevertheless, the R% has been shown to be independent of reaction time. Response optimisation revealed the highest R% (70.12%) can be achieved at 1000 ppm, 10 min of reaction time and initial pH of 2. Furthermore, K2FeO4 has a better R% in low pH regions of 2 to 4. Additionally, K2FeO4 achieved the highest R% (84%) at 1190 ppm and pH 9 with 8.5 min of reaction time. In a single coagulation stage, the use of Formula A or K2FeO4 are not able to meet Environmental Quality (Industrial Effluent) Regulations 2009 with discharge Standard B as specified by Department of Environment Malaysia, while a two-stage coagulation process can meet Standard A. Specifically, the combined formulation of using Ecogent F-Loc(1)- Formula A(2) and NaAlO2(1)- Formula A(2) were able to achieve treated water with less than 2 ppm fluoride. Moreover, recycling treated water also plays a major role in helping industries meet the strict treatment standards.

Microbial Contamination in Drinking Water of Saggiyan-Lahore, Pakistan

The present study was carried to evaluate the physico-chemical parameters and microbial contamination of drinking water in the area of Saggiyan, Lahore. The tested water samples (S1-S30) were found to contain 199.6-402 mg/L TDS, 196-260 ppm EC, 196-260 ppm Hardness, 0.8-17 NTU turbidity, 169-290 mg/L alkalinity, 0-0.1 ppb arsenic and 0-0.1 ppm fluoride contents. 95% of the water samples were found contaminated with fecal coliforms while 27% of the samples had shown the presence of E. coli. Though the physico-chemical parameters of most water samples were found in the safe limits of WHO, however, the presence of microbial contamination rendered it non-suitable for drinking purposes.

In situ evaluation of desensitizing toothpastes for protecting against erosive tooth wear and its characterization

This five-phase, single-blind, crossover in situ trial evaluated the effects of desensitizing or anti-erosive toothpastes on dentin erosive wear and tubule occlusion. Some characteristics such as relative dentin abrasivity (RDA), viscosity (V), cytotoxicity, and fluoride and calcium (Ca) availability of the toothpastes were also tested. Samples were positioned on removable intraoral appliances from 15 volunteers (n=4), according to the groups, C-control (0 ppm fluoride), F-sodium monofluorophosphate (MFP), A-MFP and arginine+calcium carbonate, CSP-calcium sodium phosphosilicate, and CS-MFP and calcium silicate+sodium phosphate. Erosion-abrasion cycling was performed (1% citric acid, 2min, 6×/day; toothbrushing, 5s, 2×/day). Surface loss (SL) was evaluated by optical profilometry. Environmental scanning electron microscopy images (ESEM) counted the number of open dentin tubules (ODTs). Data were statistically analyzed (α=0.05). There were no significant differences in SL among groups (p=0.468). The ODT for CSP, CS, and A groups were significantly lower than the control. CSP and CS presented significantly less ODT than F, but they did not significantly differ from A. F and CS were more abrasive than all the other toothpastes; CSP was more abrasive than A, and C was the least abrasive. CSP presented higher V (p<0.05). All toothpastes presented lower cell viability than the control without toothpaste exposure. F and A presented significantly higher values of F- (p<0.05). All fluoride toothpastes had similar amount of Ca, differing from the control (p<0.05). Although the toothpastes caused similar degree of erosive wear, CSP and CS were able to occlude the dentin tubules. Desensitizing toothpastes containing calcium, sodium, phosphate, and silicate could be a suitable option for treating dentin hypersensitivity.

School Based Tooth Brushing and Annual Silver Diammine Fluoride Application as a Highest Priority Package for Achieving Universal Oral Health Care for Cambodian Children

Background: Achieving Universal Oral Health Care among Low-to Middle-Income settings is challenging and little literature exists around exploring what a “Highest Priority Package” of care might look like in the context of oral health. The Healthy Kids Cambodia (HKC) program differs from most conventional school dental services in that the initial package of care that is offered is daily toothbrushing with 1,500 ppm fluoride toothpaste (DTB) together with the topical application of Silver Diamine fluoride (SDF) for management of lesions in primary teeth.Aim: To examine tooth level outcomes for 8- to 10-year old children from two schools that performed DTB with application of SDF at differing time-points.Design: This was an observational cohort study that examined lesion progression among children in late mixed dentition at two schools. Data were collected using the dmft and pufa indices. Both schools received materials and training for DTB at baseline. School One received SDF at baseline while School Two received SDF after 9-months. Intraoral examinations were performed and the presentation of primary teeth with cavitated carious lesions were compared at baseline and 12 m. If a tooth was still caries-active or had become pulpally involved, this was considered to be an unacceptable outcome. Descriptive analysis was performed the chi-squared test was used to examine differences in the proportion of teeth with unacceptable outcomes by school membership.Results: Of the 521 children recruited, 470 (90.2%) were followed. Where there was a delay in SDF application (School 2) there was a three times greater chance of an unacceptable outcome. Ten percentage of primary teeth in School One and 33% of primary teeth in the School Two had unacceptable outcomes.Conclusion: The present study offers data on expected effect sizes that might inform future step-wedged clinical trials to validate an oral health Highest Priority Package of care for Cambodian children. The delivery of a package of care that includes both DTB and SDF can prevent adverse outcomes, such as dental infections, in primary teeth with carious lesions.

Kariesprävention im Säuglings- und frühen Kindesalter

BackgroundIn the past different recommendations for caries prevention through fluoride application in infancy and early childhood (0–6 years old) existed in Germany; however, if different recommendations coexist it leads to confusion among health professionals and parents/caregivers, to a lower acceptance of the recommendations and, consequently, to insufficient implementation.MethodsJoint recommendations were formulated in a multistage process, coordinated by the Healthy Start—Young Family Network (Netzwerk Gesund ins Leben). Representatives of the relevant German medical and scientific societies, professional associations and specialized institutions participated in the process and reviewed the scientific evidence. Feasibility and accessibility were considered, also with respect to families with an increased risk of caries.RecommendationsFrom birth to tooth eruption infants should receive a supplement with 400–500 IU vitamin D and 0.25 mg fluoride. After tooth eruption, the child should gently and gradually be introduced to tooth brushing. A choice should be made between continuing systemic fluoride application (400–500 IU vitamin D and 0.25 mg fluoride) or using a toothpaste with 1000 ppm fluoride (up to 2 times 0.125 g/day, the size of a grain of rice); vitamin D supplementation is continued until the second summer in the child’s life. During the first 12 months, infants fed exclusively or predominantly on formula food are given a vitamin D supplement without fluoride if the fluoride content of the water used to prepare the formula contains ≥ 0.3 mg fluoride/l. In this case the daily amount of fluoride toothpaste should also be reduced. From 12 months on tooth brushing twice a day with a toothpaste containing fluoride (1000 ppm fluoride) is recommended, first with a small amount of toothpaste (each time up to 0.125 g, the size of a grain of rice) and then with a larger amount of toothpaste from 24 months (each time up to 0.25 g, pea-sized). To avoid excessive fluoride intake, the correct amount of toothpaste is essential. Education and advice on caries prevention and on how to put the recommendations into practice should be provided during pediatric and dental examinations as well as within the National Dental Group Prevention Program.

In vitro remineralization of enamel with a solution containing casein and fluoride.

The aim of the present study was to investigate the effects of casein in a remineralization solution on enamel remineralization. Bovine blocks were demineralized for 21 days, then, allocated into four groups. The specimens were remineralized for 21 days in the following artificial saliva solutions: 1) 0 µg/mL casein, 0 ppm fluoride (F) (C0-F0); 2) 0 µg/mL casein, 1 ppm F (C0-F1); 3) 10 µg/mL casein, 0 ppm F (C10-F0); and 4) 10 µg/mL casein, 1 ppm F (C10-F1). Micro-CT analyses were performed once a week. Specimens were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The present results suggest that casein by itself inhibits remineralization, whereas the coexistence of casein and F promotes the remineralization of caries bodies by interrupting mineral deposition on the enamel surface.

Root Caries Preventive Effect of Varnishes Containing Fluoride or Fluoride + Chlorhexidine/Cetylpyridinium Chloride In Vitro.

Caries preventive varnishes containing only fluoride might differ from those containing a combination of fluoride and antimicrobial components in terms of mineralization properties and their impact on the cariogenic biofilm. We compared a fluoride and a fluoride + chlorhexidine (CHX)/cetylpyridinium chloride (CPC) varnish on root caries formation in vitro. One hundred bovine root dentin samples were allocated to five groups (n = 20/group): (1) 7700 ppm fluoride varnish (Fluorprotector S (F)), (2) experimental placebo varnish for F (F-P), (3) 1400 ppm fluoride + 0.3% CHX/0.5% CPC varnish (Cervitec F (CF)), (4) experimental placebo varnish for CF (CF-P), (5) untreated control. Cariogenic challenge was provided using a multi-station, continuous-culture 3-species (Streptococcus mutans (SM), Lactobacillus rhamnosus (LR), Actinomyces naeslundii (AN)) biofilm model for 10 days. Mineral loss (ΔZ) was evaluated using transversal microradiography and bacterial counts in the biofilm assessed as colony-forming units. Fluorescence in situ hybridization (FISH) and confocal microscopy were performed to assess the three-dimensional biofilm architecture. Mean ± SD (vol% × μm) ΔZ was significantly lower for F (9133 ± 758) and CF (9835 ± 1677) compared to control (11362 ± 919) (p < 0.05), without significant differences between F and CF. SM counts were significantly lower and LR counts significantly higher in F- and CF-biofilms compared to control. AN counts were significantly higher in the F-biofilms than in all other groups. According to FISH, SM and LR invaded dentinal tubules only in the control-group. In the CF-group, the basal biofilm layer did not contain SM and AN. Both F and CF varnishes had similar caries-preventive effects and a considerable impact on biofilm structure and composition.

Remineralizing effect of a new strontium-doped bioactive glass and fluoride on demineralized enamel and dentine

ObjectiveTo investigate the remineralizing effect of a strontium-doped bioactive glass (HX-BGC) and fluoride on demineralized enamel and dentine. MaterialsSixty demineralized human tooth specimens were allocated to four groups. Group 1 received 5% HX-BGC, Group 2 received 5% HX-BGC and 1450 ppm fluoride, Group 3 received 1450 ppm fluoride, and Group 4 received deionized water as negative control. The specimens were subjected to pH cycling for 14 days. The surface morphology, lesion depths, crystal characteristics and collagen matrix degradation of the specimens were assessed by scanning electron microscopy (SEM), micro-computed tomography (mico-CT), X-ray diffraction (XRD), and spectrophotometry with a hydroxyproline (HYP) assay, respectively. ResultsSEM images showed the enamel surface was smooth with regularly arranged enamel rods in Groups 1–3. Granular grains were observed in both inter-tubular and intra-tubular dentine in Groups 1–3. The mean lesion depths in enamel were 80.8 μm, 50.6 μm, 72.7 μm and 130.7 μm in Groups 1–4, respectively (p < 0.001), and those in dentine were 152.6 μm, 140.9 μm, 165.4 μm and 214.1 μm, respectively (p < 0.001). The differences in mean mineral loss in enamel and in dentine between the four study groups follow the same pattern as that of the differences in lesion depth. XRD illustrated apatite formation in each group. There were no significant differences in the HYP concentrations among the four groups (p = 0.261). ConclusionCombined use of HX-BGC and fluoride can reduce mineral loss and promote remineralization of demineralized enamel and dentine through the precipitation of newly formed apatite. Clinical significanceAdjunctive use of HX-BGC may enhance the remineralization effect of fluoride in the management of early dental caries lesions.

Coherent surface structure induces unique epitaxial overgrowth of metastable octacalcium phosphate on stable hydroxyapatite at critical fluoride concentration

The phase transformation from soluble calcium phosphates to less-soluble hydroxyapatite (HAP) is a thermodynamically natural route. This process is irreversible, and effective use of poorly reactive HAP to repair teeth that have no cellular metabolism remains challenging. However, this thermodynamically controlled transformation may apparently be reversed through the fast nucleation and growth of metastable phases, leading to a reactive HAP surface. Here, the assembled HAP-nanorod phase is demonstrated to change into the metastable octacalcium phosphate (OCP) phase in a calcium phosphate solution containing 0.8 ppm fluoride. Grown OCPs display parallel surface streaks and their 11¯0 and 00l (l: odd) electron-diffraction spots are often not visible. The streaked, elongated OCP gradually grows into large plates with flat surfaces that exhibit an intense11¯0 spot. Crystal-structure models reveal that the unique epitaxial overgrowth of OCP on HAP occurs since both materials share coherent {100} faces, resulting in the distinctive disappearance of 11¯0 and 00l OCP spots. A polysynthetic twin model that reliably explains this disappearance is proposed for the growth of OCP. This apparent reverse phase transformation produces hybrid calcium phosphates consisting of HAP cores and highly reactive outer OCP layers that are promising for the repair of dentin caries. Statement of significanceThis paper demonstrates important and interesting finding regarding formation of calcium phosphates in relation to their crystal structures.We first show that hydroxyapatite (HAP), the major constituent of human teeth and bone, can reversely change to its precursor, octacalcium phosphate (OCP), contrary to thermodynamic-stability rule. This apparent reverse phase transformation occurs through sharing the coherent {100} faces of both materials under controlled fluoride concentration. Nanoscale similarity of two crystal surfaces enables structurally shared epitaxial overgrowth of OCP on HAP aided by faster growth rate of OCP than that of HAP.This reaction produces hybrid crystal consisting of outer OCP and core HAP, that has not been known before and is able to be applied to dentin caries repair.

Randomised study of intra-oral kinetics of fluoride-containing toothpastes

ObjectivesThis randomised, controlled, analyst blind, crossover study aimed to evaluate and compare salivary fluoride and calcium ion concentration over 60 min following brushing with an assigned treatment and following an orange juice (OJ) or deionised (DI) water rinse 60 min post-brushing. MethodsStudy treatments, both containing 1150 ppm fluoride as NaF and 5% w/w KNO3, were the Test (including 1.2 % w/w cocamidopropyl betaine) and Comparator (including tetrasodium pyrophosphate and sodium lauryl sulphate) toothpastes. Twenty nine participants were randomised to treatment. ResultsA sharp increase in salivary fluoride ion concentration immediately post-brushing with either toothpaste decreased over time. Fluoride concentration following Test toothpaste use was numerically higher than the Comparator at all timepoints, with a significant difference from 10 min post-brushing (p < .05). Following the 60 min rinse, there were no significant differences between the Test or Comparator + OJ groups in salivary fluoride concentration but the Test + DI water group was significantly lower than Test (p < .001) or Comparator (p < .001) + OJ groups. A reduction in salivary calcium ion concentration was seen immediately post-brushing and after the OJ rinse with both toothpastes. Significant differences were observed in favour of the Test toothpaste at all timepoints (p < .05) and for Test and Comparator + OJ group (p < .001) compared with Test + DI water rinse. Both treatments were generally well-tolerated. ConclusionsThis study demonstrated that toothpaste formulations with identical declared fluoride concentrations and the same fluoride source give rise to differing intraoral fluoride concentrations over time, which are potentially related to different formulation excipient effects. Clinical significanceBy understanding the interaction of toothpaste formulation excipients in the oral environment, formulations can be developed that maximise retention of fluoride in the oral environment.

Evaluación clínica mediante fluorescencia cuantitativa inducida por luz DIAGNOdent de la eficacia remineralizadora de dos dentífricos, estudio in vivo

Objetivo: Comparar la eficacia de dos dentífricos de distinta composición, uno de arginina, calcio y flúor y el otro a base de flúor, usado en el cepillado diario sobre lesiones cariosas diagnosticadas mediante el sistema DIAGNOdent. Materiales y Métodos: Se evaluaron dos grupos de 20 estudiantes, con edades de 12 a 14 años, quienes presentaron lesiones iniciales de caries, diagnosticadas mediante luz DIAGNOdent. Se les indicó emplear dos veces al día durante 90 días seguidos uno de los dos dentífricos probados, uno de ellos a base de arginina al 1,5%, calcio insoluble y 1450 ppm de fluoruro, y el otro a base de 1450 ppm de fluoruro. Se realizaron mediciones de las superficies dentales por medio de DIAGNOdent cada 30 días los datos fueron evaluados Originalestadísticamente mediante pruebas de Mann Whitney. Resultados: los valores obtenidos en las tres mediciones de cada una de las superficies, a los 30, 60 y 90 días fueron relacionadas considerando el grupo perteneciente, determinando que existieron diferencias significativas entre los dos dentífricos (p=0,008). Se observó un mejor desempeño en cuanto a la remineralización con el dentífrico a base de Arginina-Calcio-Flúor. Conclusiones: la acción remineralizadora de las dos pastas dentales permitió revertir la destrucción del tejido de esmalte afectado por mancha blanca, sin embargo el desempeño de la pasta dental que contiene Arginina-Calcio-Flúor fue superior a lo largo de los 90 días de evaluación.

Artificial Caries Lesion Characteristics after Secondary Demineralization with Theobromine-Containing Protocol.

Developing artificial caries lesions with varying characteristics is needed to adequately study caries process in vitro. The objective of this study was to investigate artificial caries lesion characteristics after secondary demineralization protocol containing theobromine and fluoride. Sixty bovine enamel slabs (4 × 3 mm) were demineralized using a Carbopol-containing protocol for 6 days. A baseline area (2 × 3 mm) was protected with acid-resistant nail varnish, after which specimens were exposed for 24 h to a secondary demineralization protocol containing acetic acid plus one of four fluoride/theobromine combinations (n = 15): theobromine (50 or 200 ppm) and fluoride (0 or 1 ppm). Specimens were sectioned and analyzed using transverse microradiography for changes in mineral content, lesion depth, and surface layer mineralization. Data was analyzed using paired t-test and analysis of variance followed by Bonferroni test at 0.05 significance level. After secondary demineralization, fluoride-containing groups had significantly deeper lesions (p = 0.002 and 0.014) compared to the group with 0 ppm fluoride and 50 ppm theobromine. Mineral content and lesion depth were significantly different compared to baseline for all groups. Theobromine did not show an added effect on mineral uptake. Theobromine-containing groups exhibited particularly deep lesions with a more uniform mineral profile in the presence of fluoride.

The effectiveness of using the toothpastes with a different fluoride content on the early childhood caries (ECC) reduction – systematic review

Introduction. Scientific evidence indicates the anti-caries benefits of using the 1000-1500 ppm fluoride toothpastes compared to ≤ 600 ppm in permanent dentition, while there is a small number of studies regarding effectiveness of fluoride toothpastes in children with primary dentition. Aim. The purpose of this study was to present the results of a systematic review of the literature on the effectiveness of early childhood caries (ECC) prophylaxis using low and standard toothpastes, in the age group of 1-6 years. Material and methods. The methodology was in line with the guidelines from PRISMA. Article search was performed independently by two reviewers, in six electronic databases. Narrative analysis of the mean caries increment was performed to assess the effect of fluoride toothpaste on dmft and dmfs indices. Results. Nine studies out of 136 originally identified articles were included in the systematic review. The results of the analysis comparing effect of 1000-1500 versus ≤ 600 ppm fluoride toothpastes for tooth (dmft) and surface level (dmfs) confirmed the evidence of association between level of fluoride content and ECC increment. Conclusions. This systematic review, despite some limitations, indicate a greater efficacy of toothpastes containing 1000-1500 ppm F compared to those with low fluorine content in the prevention of ECC.

An investigation into the potential anticaries benefits and contributions to mineral intake of bottled water

BackgroundBottled water has become the most consumed beverage in the United States. The authors aimed to inform the dental profession about the potential anticaries benefits of some bottled waters and to provide information about their possible contributions to fluoride, calcium, magnesium, sodium, and potassium intakes. MethodsThe authors chose a convenience sample by purchasing all different bottled waters from the main supermarkets operating in Indianapolis, Indiana. The authors analyzed the fluoride content using a fluoride ion–specific electrode and metal concentrations using atomic absorption spectroscopy. They used dietary reference intakes to calculate hypothetical intakes of all minerals. ResultsThe authors identified 92 different bottled waters. Fluoride concentrations were generally low (mean, 0.11 parts per million [ppm]; median, 0.04 ppm). Only 2 waters contained more than 0.7 ppm fluoride (0.95 ppm and 1.22 ppm). Metal concentrations varied considerably among waters. Calcium concentrations ranged from less than 0.1 through 360 ppm (mean, 26.9 ppm; median, 5.2 ppm), which were greater than those of magnesium (range, < 0.01-106 ppm; mean, 7.5 ppm; median, 1.9 ppm), sodium (range, < 0.01-109 ppm; mean, 11.1 ppm; median, 2.9 ppm), and potassium (range, < 0.01-43 ppm; mean, 3.6 ppm; median, 1.2 ppm). Overall, most bottled waters do not contribute to adequate intakes of fluoride, potassium, or sodium or to recommended dietary allowances for calcium and magnesium. Nonetheless, some waters can provide meaningful contributions to fluoride, calcium, and magnesium intake. ConclusionsThe fluoride concentration in 90 of the 92 studied bottled waters is insufficient to contribute to caries prevention. Only a few bottled waters can be considered health-promoting. Practical ImplicationsDental professionals should consider the mineral content of water consumed by their patients during caries risk assessment.

Inhibition of dentine caries using fluoride solution with silver nanoparticles: An in vitro study

ObjectivesTo investigate the remineralising and staining effects of sodium fluoride (NaF) with silver nanoparticles (AgNPs) on artificial dentine caries. MethodsHuman dentine blocks with artificial caries were divided into four groups. Group 1 received 5 % NaF (22,600 ppm fluoride) with 4000 ppm AgNPs; group 2 received 4000 ppm AgNPs; group 3 received 5 % NaF, group 4 received deionised water (negative control). All groups underwent three biochemical cycles. Each cycle included Streptococcus mutans biofilm challenge and remineralisation process. The lesion depth, mineral-organic content, surface morphology and crystal characteristics of dentine blocks were evaluated using micro-computed tomography, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction. Colour change of dentine blocks was assessed using spectrophotometry. ResultsThe mean lesion depths of groups 1–4 were 151.13 ± 29.13 μm, 172.38 ± 23.44 μm, 190.41 ± 32.81 μm and 221.24 ± 27.91 μm, respectively. The hydrogen phosphate-to-amide I ratios of groups 1–4 were 5.98 ± 0.36, 3.86 ± 0.56, 4.00 ± 0.67 and 2.53 ± 0.40, respectively. There was no significant interaction effect between AgNPs and NaF. SEM showed less exposure of dentine collagen fibres in group 1 when compared to other groups. X-ray diffraction revealed presence of silver chloride and metallic silver in group 1 and 2. There was no significant difference in colour change among the four groups (p = 0.74). ConclusionsNaF solution with AgNPs can remineralise dentine caries without staining. Clinical SignificanceSodium fluoride solutions that include silver nanoparticles have potential uses in the management of caries.

The effect of silver diamine fluoride in preventing in vitro primary coronal caries under pH-cycling conditions

ObjectivesThis study investigated the ability of SDF, and its individual components, silver (Ag+) and fluoride (F−) ions, in preventing enamel demineralization under pH-cycling conditions in the presence or absence of twice-daily fluoride application. DesignPolished human enamel specimens were assigned to five treatment groups (n = 36 per group): SDF (38 %); SDF followed by application of a saturated solution of potassium iodide (SDF + KI); silver nitrate (AgNO3; silver control, 253,900 ppm Ag); potassium fluoride (KF; fluoride control, 44,800 ppm F); deionized water. Treatments were applied once. Specimens in each treatment group were divided into two subgroups (n = 18). During the subsequent 7-day pH-cycling phase, specimens were treated twice daily with either 275 ppm fluoride as sodium fluoride or deionized water, immediately before and after a 3-h cariogenic challenge with exposure to artificial saliva at all other times. Changes in color, Vickers surface microhardness (SMH), transverse microradiography (TMR) was calculated. Data were analyzed using two-way ANOVA. ResultsIn both models, SDF, SDF + KI and KF were superior in inhibiting demineralization compared to AgNO3 and deionized water (p < 0.0001). There was no statistically significant difference between SDF, SDF + KI and KF with twice daily fluoride treatments (p > 0.8). However, KF was more effective in preventing demineralization than SDF and SDF + KI in the absence of fluoride treatments (p = 0.0002). KI did not affect the ability of SDF to prevent demineralization (p > 0.4). ConclusionSDF and SDF + KI appears to be an effective option in preventing primary coronal caries.

Recommending 1000 ppm fluoride toothpaste for caries prevention in children

The caries prevalence among Singapore children remains high, with almost 50% affected by the age of 6 years. Among oral hygiene homecare, toothpastes with a minimum fluoride concentration of 1000 ppm or greater have been shown to be more effective at preventing caries. Previous concerns with dental fluorosis have led to the marketing of non-fluoride and low-fluoride toothpastes specifically for children. In the local context, many parents start their children on these products due to ingestion concerns and recommendations of the product, rather than on sound advice from a healthcare professional. The latest recommendation is to use a smear size of 1000 ppm or greater fluoride toothpaste in children under 3 years of age with high caries risk. For children aged 3 years and older, a pea size of 1000 ppm or greater fluoride toothpaste should be used. As medical physicians are typically the first healthcare encounter for many children, they are well positioned to provide recommendations on the concentration and amount of fluoride toothpaste to be used in young children.

Zirconia-Chitosan Beads as Highly Efficient Adsorbent for Defluoridation of Water

Zirconia modified chitosan beads (Zr-CTS) have been synthesized as adsorbent for fluoride ions from water bodies. The beads were characterized using FT-IR, SEM, EDX, TG-DTA and BET surface area analysis. Batch adsorption parameters were performed for defluoridation of water using the prepared composite. The pH point of zero charge was found to be 5.7. Maximum efficiency of the adsorbent was observed at pH 4.0, with adsorbent dose of 40 mg per 25 mL of 25 ppm fluoride solution and adsorption period of 45 minutes. Under these conditions, Zr-CTS was found to have an adsorption capacity of 52.63 mg/g in accordance with Freundlich adsorption isotherm. Thermodynamics parameters revealed that the process of adsorption was spontaneous, exothermic and leading to increase in entropy. The process followed pseudo-second-order kinetics model. The used material was regenerated using 5% NaCl solution and could be reused in multiple cycles adding greener dimension.

EFFECT OF ACIDS, FLUORIDES AND BRUSHING ON ENAMEL – AN IN-VITRO STUDY

Objective: To determine the effect of fluoride, citric acid and brushing on tooth enamel. Materials and Methods: This in vitro experimental study was conducted on 60 extracted premolars at Khyber College of Dentistry and Experimental procedure was performed at laboratory, Physics Department, Peshawar University. All maxillary and mandibular premolar teeth with normal tooth morphology extracted for orthodontic reasons and of both genders were included. Premolar teeth restored with fillings or crowns, pathologically affected teeth with caries, Amelogenesis/Dentinogensis Imperfecta, root canal treated teeth or teeth with surface loss (attrition, abrasion, erosion) were excluded from study. The effect on enamel was determined in term of weight change.Paired t test was applied to see the statistical evidence for difference in weight while Independent samples t test was applied to see the effect of different concentration of fluorides at p-value ≤ 0.05. Results: The weight of enamel decreased after immersion in citric acid (-4.134±139.34 mg), coke (-4.134±138.34 mg) and after brushing (-4.404±111.642 mg) statistically significantly (P&lt;0.05). The increase in weight was statistically significant for 450 ppm fluoride (P=0.017) but insignificant after immersion in 225 ppm fluoride (P=.067). Conclusion: Fluoride should be routine part of oral hygiene measures. In patients who are more prone to cariogenic insults, especially physically handicapped and undergoing orthodontic treatment. The increased concentration of fluoride is recommended to enhance remineralization.

Dentifrices or gels containing MMP inhibitors prevent dentine loss: in situ studies.

Evaluate the effect of dentifrices or gels containing MMP inhibitors on dentine loss in situ. Acrylic palatal appliances containing bovine dentine blocks were divided into two rows, corresponding to the groups erosion (ERO) and erosion associated with abrasion (ERO+ABR). For ERO, the appliances were immersed in a cola drink for 5 min, 4 times/day, while for ERO+ABR, the blocks were brushed for 15 sec with a dentifrice slurry after the second and third erosive challenges. Ten volunteers took part in study 1 (S1), where the dentifrices evaluated contained 1100 ppm fluoride as NaF, 0.61% green tea extract, or 0.012% chlorhexidine digluconate. Thirteen volunteers participated in study 2 (S2), in which the treatment was performed only once (1 min) with gels containing 400 μM EGCG (EGCG400), 0.012% chlorhexidine, 1 mM FeSO4, 1.23% F (NaF), placebo, or received no treatment. Dentine loss was analyzed by profilometry (μm). Regarding S1, ERO+ABR induced significantly higher dentine loss compared with ERO and all dentifrices tested led to significantly lower dentine loss when compared with placebo. For S2, regardless of the conditions or times of evaluation, gels containing EGCG, CHX, or FeSO4 led to significantly less wear compared with the other groups. Both dentifrices and gels containing MMP inhibitors significantly reduced dentine loss. Dentifrices and gels containing MMP inhibitors are able to increase the protection against dentine wear, although gels have a better effect when compared with fluoride gel, lasting up to 10 days after a single application.