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Combination effect of fluoride dentifrices and varnish on deciduous enamel demineralization
Gatti, Alessandra;Camargo, Lucila Basto;Imparato, José Carlos Pettorossi;Mendes, Fausto Medeiros;Raggio, Daniela Prócida;
Brazilian Oral Research , 2011, DOI: 10.1590/S1806-83242011000500010
Abstract: the aim of this study was to evaluate the anticaries potential of 500 or 1100 ppm f dentifrices combined with fluoride varnish using a ph-cycling regimen. seventy primary canines were covered with nail polish, leaving a 4×4 mm window on their buccal surface, and randomly assigned into 7 groups (n = 10): s: sound enamel not submitted to the ph-cycling regimen or treatment; n: negative control, submitted to the ph-cycling regimen without any treatment; d1 and d2: subjected to the ph-cycling regimen and treated twice daily with 1100 or 500 ppm f dentifrice, respectively; vf: fluoride varnish (subjected to f-varnish before and in the middle of the ph-cycling regimen); and vf+d1 and vf+d2. after 10 days, the teeth were sectioned, and enamel demineralization was assessed by cross-sectional hardness at different distances from the dental surface. data were analyzed using a two-way anova followed by tukey's test. dentifrice with 1100 ppm f and the combination of f-varnish with the dentifrices significantly reduced enamel demineralization compared with the negative control (p < 0.05), but the isolated effects of f-varnish and dentifrice with low concentration were not significant (p > 0.05). the effect of combining f-varnish with the dentifrices was not greater than the effect of the dentifrices alone (p < 0.05). the data suggest that the combination of f-varnish with dentifrices containing 500 and 1100 ppm f is not more effective in reducing demineralization in primary teeth than the isolated effect of dentifrice containing 1100 ppm f.
Effect of pH of amine fluoride containing toothpastes on enamel remineralization in vitro
Wolfgang H Arnold, Anabel Haase, Julia Hacklaender, Zeno Gintner, Jolan Bánóczy, Peter Gaengler
BMC Oral Health , 2007, DOI: 10.1186/1472-6831-7-14
Abstract: A 5 × 5 mm window on the enamel surface of 40 caries free extracted human premolars was demineralized in a hydroxyethylcellulose solution at pH 4.8. The teeth were divided into 8 groups and the lower half of the window was covered with varnish serving as control. Each group was then immersed in toothpaste slurry containing amine fluoride (1400 ppm) at pH 4.1, 4.5, 5.1 and 6.9 or control toothpaste slurry without fluoride at pH 4.3, 4.7, 5.3 and 7.0. Serial sections were cut through the lesions and investigated with polarization light microscopy and quantitative EDX element analysis.The PLM results showed a decreased porous volume of the body of the lesion after incubation with fluoridated toothpaste at pH 4.53 and 5.16. No differences between the experimental window and the control window were found in the other groups. The quantitative element analysis showed no differences in the element content of any of the groups.From the results it can be concluded that slightly acidified fluoridated dentifrices may have a certain positive effect on enamel remineralization.Dental caries progression or reversal depends upon the balance between demineralization and remineralization [1]. This balance is depended from several factors e.g. salivary Ca and P concentration, bioavailability of fluoride and pH. Remineralization occurs when the pH raises and Ca and P from saliva together with fluoride are forming new hydroxyapatite crystals on the enamel surface and the body of the lesion [2,3]. Mineral loss of incipient caries lesions is inversely proportional to the degree of saturation of Ca and P ions and the pH of the solution The critical pH range for demineralization and remineralization is between 4.3 and 5.0 where lesions with well defined surface layers occur whereas at pH levels around 6.0 no surface layers are forming [4].Fluoride plays an important role in the remineralization process. Although a dose-response effect of fluoride enhancing enamel remineralization has been fo
Dental enamel around fixed orthodontic appliances after fluoride varnish application
Gontijo, Leonardo;Cruz, Roberval de Almeida;Brand?o, Paulo Roberto Gomes;
Brazilian Dental Journal , 2007, DOI: 10.1590/S0103-64402007000100011
Abstract: poor oral hygiene has been considered one of the main problems routinely faced in the orthodontic treatment. orthodontic appliance creates an environment that provides mineral loss from the dental enamel. such condition is clinically seen as white spot lesions and cavitations in the most severe cases. the aim of this study was to evaluate the effects of a fluoride varnish application as a caries prevention method for clinical orthodontics. the experiment analyzed dental enamel adjacent to orthodontics accessories after treatment. in addition, it was observed the calcium, phosphorus and fluoride contents on enamel treated with a fluoride varnish. the results showed that fluoride varnish application is a simple and fast technique that could be useful in preventing enamel demineralization associated to orthodontic treatment. scanning electron microscopy revealed significant amount of calcium fluoride-like material deposited on enamel and energy dispersive x-ray analysis demonstrated a large incorporation of calcium and fluoride to the enamel of the treated specimens. it was concluded that fluoride varnish could indeed be considered an efficient preventive method to enhance enamel resistance against the cariogenic challenges during orthodontic therapy.
Effect of plaque accumulation and salivary factors on enamel demineralization and plaque composition in situ
Tenuta, Livia Maria Andaló;Lima, José Eduardo de Oliveira;Cardoso, Celso Luiz;Tabchoury, Cínthia Pereira Machado;Cury, Jaime Aparecido;
Pesquisa Odontológica Brasileira , 2003, DOI: 10.1590/S1517-74912003000400006
Abstract: this study evaluated the effect of some plaque and salivary factors on caries progression in situ. the salivary secretion rate, buffering capacity and mutans streptococci counts from 13 volunteers were determined. for three distinct periods of time, 4, 7 and 10 days, each of them wore a palatal appliance containing 4 bovine enamel blocks. they used a non-fluoridated dentifrice during the experiment and a 20% sucrose solution was dripped onto the blocks 10 times a day. mutans streptococci (ms), calcium (ca), and insoluble polysaccharide (ip) were quantified in the dental plaque formed on the enamel blocks, after each period. enamel demineralization was assessed by surface microhardness, and the percentage of surface microhardness change (%smc) in relation to the baseline values was calculated. enamel demineralization occurred after each period of plaque accumulation (p < 0.05), and the %smc increased with time (from 13.8 to 48.3%). the concentrations of ca and ip in plaque were not statistically different among the experimental times, but significant correlations were found between these concentrations and %smc. neither the salivary factors assessed initially nor mutans streptococci in plaque presented statistically significant correlations to %smc. the results suggest that enamel demineralization is time-dependent and is more related to the composition of the biofilm formed than to the salivary factors studied.
Effect of plaque accumulation and salivary factors on enamel demineralization and plaque composition in situ
Tenuta Livia Maria Andaló,Lima José Eduardo de Oliveira,Cardoso Celso Luiz,Tabchoury Cínthia Pereira Machado
Pesquisa Odontológica Brasileira , 2003,
Abstract: This study evaluated the effect of some plaque and salivary factors on caries progression in situ. The salivary secretion rate, buffering capacity and mutans streptococci counts from 13 volunteers were determined. For three distinct periods of time, 4, 7 and 10 days, each of them wore a palatal appliance containing 4 bovine enamel blocks. They used a non-fluoridated dentifrice during the experiment and a 20% sucrose solution was dripped onto the blocks 10 times a day. Mutans streptococci (MS), calcium (Ca), and insoluble polysaccharide (IP) were quantified in the dental plaque formed on the enamel blocks, after each period. Enamel demineralization was assessed by surface microhardness, and the percentage of surface microhardness change (%SMC) in relation to the baseline values was calculated. Enamel demineralization occurred after each period of plaque accumulation (p < 0.05), and the %SMC increased with time (from 13.8 to 48.3%). The concentrations of Ca and IP in plaque were not statistically different among the experimental times, but significant correlations were found between these concentrations and %SMC. Neither the salivary factors assessed initially nor mutans streptococci in plaque presented statistically significant correlations to %SMC. The results suggest that enamel demineralization is time-dependent and is more related to the composition of the biofilm formed than to the salivary factors studied.
Effects of Ion-Releasing Tooth-Coating Material on Demineralization of Bovine Tooth Enamel  [PDF]
Koji Kawasaki,Masaki Kambara
International Journal of Dentistry , 2014, DOI: 10.1155/2014/463149
Abstract: We compared the effect of a novel ion-releasing tooth-coating material that contained S-PRG (surface-reaction type prereacted glass-ionomer) filler to that of non-S-PRG filler and nail varnish on the demineralization of bovine enamel subsurface lesions. The demineralization process of bovine enamel was examined using quantitative light-induced fluorescence (QLF) and electron probe microanalyzer (EPMA) measurement. Ion concentrations in demineralizing solution were measured using inductively coupled plasma atomic (ICP) emission spectrometry and an ion electrode. The nail varnish group and the non-S-PRG filler group showed linear demineralization. Although the nail varnish group and the non-S-PRG filler group showed linear demineralization, the S-PRG filler group did not. Further, plane-scanning by EPMA analysis in the S-PRG filler group showed no changes in Ca ion distribution, and F ions showed peak levels on the surface of enamel specimens. Most ions in the demineralizing solution were present at higher concentrations in the S-PRG filler group than in the other two groups. In conclusion, only the S-PRG filler-containing tooth-coating material released ions and inhibited demineralization around the coating. 1. Introduction In recent years, oral health in developed countries has improved, with the majority of people keeping more sound teeth for longer duration [1–7]. In particular, considerable interest has been directed at detecting caries at early stages, with the development of the International Caries Detection and Assessment System (ICDAS) [8, 9] and quantitative light-induced fluorescence (QLF) method [10, 11]. In current daily dental practice and oral health care programs, the inhibition of initial tooth enamel demineralization and the promotion of remineralization are the most important targets [12–14]. Surface-reaction type prereacted glass-ionomer (S-PRG) filler [15, 16] has been reported to have biological efficacy in reducing dental plaque formation [17, 18], inhibition of dentin demineralization [19], fluoride release and recharge potential [20], and prevention of demineralization in surrounding orthodontic brackets [21]. These efficacies might be due to the ability of S-PRG filler to release various ion species (fluoride, strontium, aluminum, sodium, etc.) as well as its capacity as an acid buffer [22]. S-PRG filler can therefore be found in various dental products, such as composite resin, root canal sealer, orthodontic resin bonding systems, and denture base resin [19, 23–28]. We developed a novel ion-releasing tooth-coating material
Effect of Nd:YAG laser combined with fluoride on the prevention of primary tooth enamel demineralization
Azevedo, Danielle Torres;Faraoni-Romano, Juliana Jendiroba;Derceli, Juliana dos Reis;Palma-Dibb, Regina Guenka;
Brazilian Dental Journal , 2012, DOI: 10.1590/S0103-64402012000200003
Abstract: most studies dealing with the caries preventive action of nd:yag laser have been done in permanent teeth and studies on primary teeth are still lacking. the aim of this study was to evaluate in vitro the effect of nd:yag laser combined or not with fluoride sources on the acid resistance of primary tooth enamel after artificial caries induction by assessing longitudinal microhardness and demineralization depth. sixty enamel blocks obtained from the buccal/lingual surface of exfoliated human primary molars were coated with nail polish/wax, leaving only a 9 mm2 area exposed on the outer enamel surface, and randomly assigned to 6 groups (n=10) according to the type of treatment: c-control (no treatment); apf: 1.23% acidulated phosphate fluoride gel; fv: 5% fluoride varnish; l: nd:yag laser 0.5 w/10 hz in contact mode; apfl: fluoride gel + laser; fvl: fluoride varnish + laser. after treatment, the specimens were subjected to a des-remineralization cycle for induction of artificial caries lesions. longitudinal microhardness data (%lmc) were analyzed by the kruskal-wallis test and demineralization depth data were analyzed by oneway anova and fisher’s lsd test (á=0.05). apfl and apf groups presented the lowest percentage of microhardness change (p<0.05). demineralization depth was smaller in all treated groups compared with the untreated control. in conclusion, nd:yag laser combined or not with fluoride gel/varnish was not more effective than fluoride alone to prevent enamel demineralization within the experimental period.
In vitro induction of enamel subsurface demineralization for evaluation of diagnostic imaging methods
Ferreira, Rívea Inês;Haiter-Neto, Francisco;Tabchoury, Cínthia Pereira Machado;Bóscolo, Frab Norberto;
Journal of Applied Oral Science , 2007, DOI: 10.1590/S1678-77572007000500004
Abstract: the aim of this study was to investigate a model of inducing enamel subsurface demineralization for evaluating diagnostic imaging methods. fifty sound teeth had their crowns coated with acid-resistant varnish, leaving a 7 mm2 circular window of exposed enamel in one of the proximal surfaces. the specimens were assigned to 5 groups (4 experimental and the control) and were kept immersed in a buffer solution at ph 4.8, 50% saturated in relation to enamel, for 60, 75, 90 and 120 days, or were not exposed to the solution. digital radiographs were taken, prior to and after each immersion period, and interpreted by a radiologist. for validation, the enamel was submitted to microhardness profiling. in addition, the solutions were analyzed for phosphorus (pi) and calcium (ca) concentrations. microhardness data were evaluated using two-way anova (p<0.05) and tukey's test. pi and ca concentrations were compared using one-way anova (a = 0.05). the performance of radiography was assessed by roc analysis. the microhardness values for the control group ranged from 405 to 432 khn. of the 4 experimental groups, the 60-day group demonstrated the highest values (179-379 khn) and the 120-day group, the lowest values (103-277 khn). the lowest total concentrations of pi and ca (1.74 mm and 2.63 mm, respectively) were found in the solutions of the 60-day group, indicating the lowest rate of mineral loss, however, there was no significant difference among the other experimental groups. the performance for detecting images consistent with caries lesions was high (az = 0.89). therefore, this in vitro model of inducing demineralization may be considered suitable for research intended to evaluate imaging methods for the diagnosis of proximal caries lesions.
Effect of fluoride toothpastes on enamel demineralization
Wolfgang H Arnold, Andreas Dorow, Stephanie Langenhorst, Zeno Gintner, Jolan Bánóczy, Peter Gaengler
BMC Oral Health , 2006, DOI: 10.1186/1472-6831-6-8
Abstract: A 3 × 3 mm window on the enamel surface of 90 human premolars was demineralized in a hydroxyethylcellulose solution at pH 4.8. The teeth were divided into 6 groups and the lower half of the window was covered with varnish serving as control. The teeth were immersed in a toothpaste slurry containing: placebo tooth paste (group 1); remineralization solution (group 2); Elmex Anticaries (group 3); Elmex Sensitive (group 4); Blend-a-med Complete (group 5) and Colgate GRF (group 6). Ten teeth of each group were used for the determination of the F- content in the superficial enamel layer and acid solubility of enamel expressed in soluble phosphorus. Of 6 teeth of each group serial sections were cut and investigated with polarization light microscopy (PLM) and quantitative energy dispersive X-ray analysis (EDX).The PLM results showed an increased remineralization of the lesion body in the Elmex Anticaries, Elmex Sensitive and Colgate GRF group but not in the Blend-a-med group. A statistically significant higher Ca content was found in the Elmex Anticaries group. The fluoride content in the superficial enamel layer was significantly increased in both Elmex groups and the Blend-a-med group. Phosphorus solubility was significantly decreased in both Elmex groups and the Blend-a-med group.It can be concluded that amine fluoride compounds in toothpastes result in a clearly marked remineralization of caries like enamel lesions followed by sodium fluoride and sodium monofluorophosphate formulations.Today, the caries preventive effect of fluoride is without any doubt. Among caries preventive protocols fluoride containing dentifrices are well accepted. For the caries preventive effect the bioavailability of fluoride is of importance [1]. Bioavailability of fluoride is dependent from the solubility of the fluoride containing compound and from the adhesion of the fluoride compound to the surface [2]. In dentifrices different fluoride formulations are used as carrier for fluoride ions o
Longitudinal evaluation of mineral loss at the earliest stage of enamel demineralization using micro-computed tomography  [PDF]
Koji Watanabe, Tomomi Nakamura, Takashi Ogihara, Yoshiyuki Ochiai, Shigeru Watanabe
Health (Health) , 2012, DOI: 10.4236/health.2012.46055
Abstract: As the prevalence of dental caries decreases, the diagnosis and treatment of initial mineral loss resulting in white spot lesions have been getting more and more important. Since dental CT provides computed tomography images of a tooth with radiation exposure similar to panoramic radiography, it will become possible in the near future to evaluate the enamel mineral density using CT in the same way as measurement of the bone mineral density. Such computed tomography images enable dentists to perform longitudinal, three-dimensional, and precise evaluation of the enamel mineral density before a demineralized lesion becomes detectable by any other traditional means. Despite their advantage, there are not enough reports on evalu- ation of the enamel mineral density using CT. This study evaluated the serial changes in mineral density in the earliest stage of enamel demineralization. Eight bovine enamel specimens were coated with nail varnish. On each specimen, 4 square windows measuring 1 mm2 were created. The specimens were incubated in lactic acid solution at 38?C. During incubation, the windows were covered by nail varnish one by one at 30, 60, and 90 minutes, respectively. At 120 minutes, the specimens were removed from the solution. After the nail varnish was removed, X-ray microradiography was performed using SKYSCAN1172 at settings of 100 kV and 100 μA. The mean Hounsfield unit values (HUV) of enamel in a non-window area and those in the window areas were calculated every 180 μm over a depth of 0 - 900 μm and analyzed by two-way ANOVA. Data were affected by the incubation time and depth from the enamel surface, and there was not interaction between the two factors. Considering the incubation time, HUV of the whole measured enamel (0 - 900 μm) in the non-window group was significantly higher than that of the other incubated groups. Considering the depth, HUV was decreased at 721 - 900 μm compared with that at 0 - 180 μm in the 30-minute-incubated group, and the decrease spread to 361 - 900 μm in the 60- and 90- minutes-incubated groups. HUV was additionally calculated at increments of 18 μm and compared within the 60-minute-incubated group, and changes in the mineral density at the boundary of the earliest demineralized lesion could be observed. This study demonstrated detailed mineral density changes in the earliest period of demineralization.
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