Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 41
Filter
1.
J. appl. oral sci ; 29: e20210120, 2021. tab, graf
Article in English | LILACS | ID: biblio-1340104

ABSTRACT

Abstract Objective Our study aims to synthesize, characterize, and determine the effects of a ChNPs suspension on human enamel after cariogenic challenge via pH-cycling. Methodology ChNPs were synthesized by ion gelation and characterized by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering. Forty enamel blocks were divided into four groups (n=10/group): (i) ChNPs suspension; (ii) chitosan solution; (iii) 0.05% sodium fluoride (NaF) solution; and (iv) distilled water. Specimens were exposed to cariogenic challenge by cycling in demineralization solution (3 h) and then remineralized (21h) for 7 days. Before each demineralization cycle, the corresponding solutions were passively applied for 90 s. After 7 days, specimens were examined for surface roughness (Ra) and Knoop hardness (KHN) before and after the cariogenic challenge; % KHN change (variation between initial and final hardness), and surface topography by an optical profilometer. The data were analyzed by repeated-measures ANOVA, One-way ANOVA, and Tukey tests (α=0.05). Results TEM images showed small spherical particles with diameter and zeta potential values of 79.3 nm and +47.9 mV, respectively. After the challenge, all groups showed an increase in Ra and a decrease in KHN values. Optical profilometry indicated that ChNPs- and NaF-treated specimens showed uneven roughness interspersed with smooth areas and the lowest %KHN values. Conclusion The ChNPs suspension was successfully synthesized and minimized human enamel demineralization after a cariogenic challenge, showing an interesting potential for use as an oral formulation for caries prevention.


Subject(s)
Humans , Tooth Demineralization/prevention & control , Chitosan , Nanoparticles , Sodium Fluoride , Cariostatic Agents , Dental Enamel , Hardness
2.
Actual. osteol ; 15(3): 205-213, Sept-Dic. 2019. ilus, tab
Article in English | LILACS | ID: biblio-1104336

ABSTRACT

The dental caries is a progressive destruction of the teeth tissue due to the disbalance in the normal molecule interactions between the enamel and the bio!lm, which alters the demineralization-remineralization process. Milk fermentation produces caseinphosphopeptides with proved remineralizing capacity of the enamel. The presence of these peptides in fermented milk with ke!r grains has been described. The purpose of this work was to evaluate in vitro the capacity of milk ke!r to prevent the demineralization of dental enamel. Bovine incisors (n=68, 17 per group) were treated for 72 h with different solutions: I: artificial saliva at pH 7.2 , II: demineralizing solution at pH 4.5, III: supernatant of kefir fermented milk at pH 4.5, IV: milk supernatant at pH 4.5. The effects of treatments were evaluated by the change in the weight of the specimens, calcium concentration in the solution and by scanning electron microscopy (SEM) of the enamel. Kefir milk supernatant prevented the demineralization process, that was evidenced by a change in weight and calcium concentration that were not different from group I, although the pH was 4.5. In contrast, group IV showed a decrease in weight and an increase in calcium concentration, compared with group I (one way ANOVA, p<0.05). Images of SEM agree with the values of weight and calcium concentration. These results indicate that kefir milk supernatant has a protective effect on enamel demineralization in vitro. (AU)


La caries dental es una patología debido a un desequilibrio en las interacciones moleculares normales entre el esmalte y la biopelícula, que altera el proceso de desmineralización remineralización. La fermentación de la leche produce fosfopéptidos de caseína con probada capacidad remineralizante del esmalte, y se ha descripto la presencia de estos péptidos en la leche fermentada con granos de kéfir. El propósito de este trabajo fue evaluar in vitro la capacidad del kéfir de leche para prevenir la desmineralización del esmalte dental. Sesenta y ocho incisivos bovinos (17 por grupo) fueron tratados durante 72 h con diferentes soluciones: I: saliva artificial, pH 7.2, II: solución desmineralizante, pH 4.5, III: sobrenadante de leche fermentada con kefir, pH 4.5, IV: sobrenadante de leche, pH 4.5. El proceso de desmineralización se evaluó mediante el cambio en el peso de las muestras, la concentración de calcio en la solución y microscopía electrónica de barrido (SEM) del esmalte. El sobrenadante de leche fermentada con kéfir impidió el proceso de desmineralización, que se evidenció por un cambio en el peso y la concentración de calcio que no discreparon del grupo I, a pesar de haber tenido un pH de 4.5. En contraste, el grupo IV mostró una disminución en el peso y un aumento en la concentración de calcio, en comparación con el grupo I (ANOVA a un criterio, p<0.05). Las imágenes SEM concuerdan con los cambios en el peso y la concentración de calcio en los grupos estudiados. Los datos obtenidos demuestran que el sobrenadante de la leche tratada con kéfir tiene un efecto protector sobre la desmineralización del esmalte in vitro, inducida por el pH ácido. (AU)


Subject(s)
Animals , Cattle , Tooth Demineralization/prevention & control , Kefir/microbiology , Saliva, Artificial/administration & dosage , Tooth Remineralization/methods , In Vitro Techniques , Cattle , Caseins/therapeutic use , Calcium/analysis , Tooth Demineralization/pathology , Tooth Demineralization/therapy , Biofilms , Dental Caries/prevention & control , Dental Enamel/cytology , Dental Enamel/physiopathology , Milk/microbiology , Formaldehyde/administration & dosage
3.
Braz. oral res. (Online) ; 33: e015, 2019. tab, graf
Article in English | LILACS | ID: biblio-989477

ABSTRACT

Abstract We assessed the effect of a new coating material based on resin-modified glass-ionomer with calcium (Ca) in inhibiting the demineralization of underlying and adjacent areas surrounding caries-like lesions in enamel. The measures used were surface hardness (SH) and cross-sectional hardness (CSH). Thirty-six bovine enamel specimens (3 × 6 × 2 mm) were randomly allocated into three groups (n = 12): No treatment (NT); resin-modified glass-ionomer with Ca (Clinpro XT Varnish, 3M ESPE) (CL), and fluoride varnish (Duraphat, Colgate) (DU). The specimens were subjected to alternated immersions in demineralizing (6 h) and remineralizing solutions (18 h) for 7 days. SH measurements were conducted at standard distances of 150, 300, and 450 µm from the treatment area. CSH evaluated the mean hardness profile over the depth of the enamel surface and at standard distances from the materials. The energy-dispersive X-ray spectroscopy analysis was conducted to evaluate the demineralization bands created on the sublayer by % of calcium (Ca), phosphorus (P), and fluoride (F). Ca/P weight ratio was also calculated. Based on SH and CSH measurements, there was no difference between groups at the distances 150 µm (p = 0.882), 300 µm (p = 0.995), and 450 µm (p = 0.998). Up to 50 µm depth (at 150 µm from the treatment area), CL showed better performance than DU ( p< 0.05). NT presented higher loss of Ca and P than CL and DU (p < 0.05). There was no significant difference in the % of F ion among the three groups. The new coating material was similar to F varnish in attenuating enamel demineralization.


Subject(s)
Animals , Cattle , Calcium/chemistry , Resin Cements/chemistry , Dental Enamel/drug effects , Glass Ionomer Cements/chemistry , Reference Values , Sodium Fluoride/chemistry , Spectrometry, X-Ray Emission , Surface Properties/drug effects , Time Factors , Materials Testing , Cariostatic Agents/chemistry , Random Allocation , Fluorides, Topical/chemistry , Reproducibility of Results , Tooth Demineralization/prevention & control , Hardness Tests , Hydrogen-Ion Concentration
4.
Braz. oral res. (Online) ; 33: e010, 2019. tab, graf
Article in English | LILACS | ID: biblio-989483

ABSTRACT

Abstract This in situ study aimed to evaluate the antibacterial and anti-demineralization effects of an experimental orthodontic adhesive containing triazine and niobium phosphate bioglass (TAT) around brackets bonded to enamel surfaces. Sixteen volunteers were selected to use intra-oral devices with six metallic brackets bonded to enamel blocks. The experimental orthodontic adhesives were composed by 75% BisGMA and 25% TEGDMA containing 0% TAT and 20% TAT. Transbond XT adhesive (TXT) was used as a control group. Ten volunteers, mean age of 29 years, were included in the study. The six blocks of each volunteer were detached from the appliance after 7 and 14 days to evaluate mineral loss and bacterial growth including total bacteria, total Streptococci, Streptococci mutans, and Lactobacilli. Statistical analysis was performed using GLM model - univariate analysis of variance for microhardness and 2-way ANOVA for bacterial growth (p<0.05). The 20% TAT adhesive caused no difference between distances from bracket and the sound zone at 10-µm deep after 7 and 14 days. After 14 days, higher mineral loss was shown around brackets at 10- to 30-µm deep for TXT and 0% TAT adhesives compared to 20% TAT. S. mutans growth was inhibited by 20% TAT adhesive at 14 days. Adhesive with 20% TAT showed lower S. mutans and total Streptococci growth than 0% TAT and TXT adhesives. The findings of this study show that the adhesive incorporated by triazine and niobium phosphate bioglass had an anti-demineralization effect while inhibiting S. mutans and total Streptococci growth. The use of this product may inhibit mineral loss of enamel, preventing the formation of white spot lesions.


Subject(s)
Humans , Male , Female , Adult , Young Adult , Oxides/pharmacology , Phosphates/pharmacology , Streptococcus/drug effects , Tooth Demineralization/prevention & control , Dental Cements/pharmacology , Lactobacillus/drug effects , Anti-Bacterial Agents/pharmacology , Niobium/pharmacology , Ceramics/pharmacology , Ceramics/chemistry , Double-Blind Method , Dental Cements/chemistry , Anti-Bacterial Agents/chemistry
5.
J. appl. oral sci ; 27: e20180514, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-1012510

ABSTRACT

Abstract Objectives: The aim of this study was to assess the effect of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves hydroalcoholic extracts on viability and metabolism of a microcosm biofilm and on enamel demineralization prevention. Methodology: Microcosm biofilm was produced on bovine enamel using inoculum from pooled human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. The biofilm was daily-treated with the extracts for 1 min. At the end, it was analyzed with respect to viability by fluorescence, CFU counting and extracellular polysaccharides (phenol-sulphuric acid colorimetric assay) and lactic acid (enzymatic assay) production. The demineralization was measured by TMR. The data were compared using ANOVA or Kruskal-Wallis (p<0.05). Results: M. urundeuva All. at 100, 10 and 0.1 μg/mL and Q. grandiflora Mart. at 100 and 0.1 μg/mL reduced biofilm viability similarly to positive control (chlorhexidine) and significantly more than the negative-vehicle control (35% ethanol). M. urundeuva at 1000, 100 and 0.1 μg/mL were able to reduce both lactobacilli and mutans streptococci CFU counting, while Q. grandiflora (1000 and 1.0 μg/mL) significantly reduced mutans streptococci CFU counting. On the other hand, the natural extracts were unable to significantly reduce extracellular polysaccharides and lactic acid productions neither the development of enamel carious lesions. Conclusions: The extracts showed antimicrobial properties on microcosm biofilm, however, they had no effect on biofilm metabolism and caries protection.


Subject(s)
Animals , Male , Cattle , Plant Extracts/pharmacology , Tooth Demineralization/prevention & control , Biofilms/drug effects , Anacardiaceae/chemistry , Myrtales/chemistry , Anti-Infective Agents/pharmacology , Polysaccharides, Bacterial/metabolism , Saliva/chemistry , Streptococcus mutans/drug effects , Microradiography/methods , Colony Count, Microbial , Cariostatic Agents/pharmacology , Microbial Sensitivity Tests , Reproducibility of Results , Plant Leaves/chemistry , Lactic Acid/metabolism , Dental Enamel/drug effects , Dental Enamel/microbiology , Microbial Viability/drug effects , Lactobacillus/drug effects
6.
J. appl. oral sci ; 27: e20180188, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-984574

ABSTRACT

Abstract Sources of calcium and phosphate have been added to dental restorative materials to improve their anticaries effect. Objective This study evaluated the effect of adding calcium glycerophosphate (CaGP) to resin-modified glass ionomer cement (RMGIC) on the physico-mechanical properties, ion release, and enamel demineralization. Material and Methods: Specimens were fabricated for each experimental group: RMGIC without CaGP (Control), RMGIC with 1, 3 and 9% CaGP. To determine the release of fluoride (F), calcium (Ca) and phosphorus (P), six specimens were immersed in demineralization and remineralization solutions for 15 days. In another experimental trial, the following physico-mechanical properties were evaluated at time intervals of 1 and 7 days after fabrication: compressive strength (n=12), diametral tensile strength (n=12), surface hardness of material (n=6) and the degree of conversion of monomers (n=8). To study enamel demineralization, specimens (n=12) were attached to enamel blocks and submitted to pH-cycling. Subsequently, surface and cross-sectional hardness and the concentration of F, Ca and P in enamel were determined. Results The addition of CaGP to RMGIC led to higher mean release of F, Ca and P when compared with control (p<0.001). Mechanical properties were within the range of those of the ionomer cements after addition of 1% and 3% CaGP. The degree of conversion did not differ between groups at the 1st and the 7th day (p>0.439). The addition of 3% and 9% CaGP reduced mineral loss and increased F, Ca and P in the enamel when compared with control (p<0.05). Conclusion The addition of 3% CaGP in RMGIC increased the release of F, P and Ca, reduced enamel demineralization, and maintained the physico-mechanical properties within the parameters for this material.


Subject(s)
Humans , Tooth Demineralization/prevention & control , Resin Cements/chemistry , Dental Enamel/drug effects , Glass Ionomer Cements/chemistry , Glycerophosphates/chemistry , Phosphates/analysis , Reference Values , Surface Properties , Time Factors , Materials Testing , Photomicrography , Calcium/analysis , Reproducibility of Results , Compressive Strength , Dental Enamel/chemistry , Fluorides/analysis , Hardness Tests
7.
J. appl. oral sci ; 27: e20180044, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975876

ABSTRACT

Abstract Radiation-related caries are one the most undesired reactions manifested during or after head and neck radiotherapy. Fluoride application is an important strategy to reduce demineralization and enhance remineralizaton. Objective: To evaluate the effect of the topical application of fluoride during irradiation on dental enamel demineralization. Material and Methods: Thirty molars were randomly divided into three groups: Non-irradiated (NI), Irradiated (I), Irradiated with fluoride (IF). Each group was subdivided according to the presence or absence of pH-cycling (n=5). In the irradiated groups, the teeth received 70 Gy. The enamel's chemical composition was measured using Fourier Transform Infrared Spectrometry (organic matrix/mineral ratio - M/M and relative carbonate content - RCC). Vickers microhardness (VHN) and elastic modulus (E) were evaluated at three depths (surface, middle and deep enamel). Scanning electron microscopy (SEM) was used to assess the enamel's morphology. Results: The FTIR analysis (M/M and RCC) showed significant differences for irradiation, pH-cycling and the interaction between factors (p<0.001). Without pH-cycling, IF had the lowest organic matrix/mineral ratio and relative carbonate content. With pH-cycling, the organic matrix/mineral ratio increased and the relative carbonate content decreased, except for IF. VHN was influenced only by pH-cycling (p<0.001), which generated higher VHN values. ANOVA detected significant differences in E for irradiation (p<0.001), pH-cycling (p<0.001) and for the interaction between irradiation and pH-cycling (p<0.001). Increased E was found for group I without pH-cycling. With pH-cycling, groups I and IF were similar, and showed higher values than NI. The SEM images showed no morphological changes without pH-cycling. With pH-cycling, fluoride helped to maintain the outer enamel's morphology. Conclusions: Fluoride reduced mineral loss and maintained the outer morphology of irradiated and cycled enamel. However, it was not as effective in preserving the mechanical properties of enamel. Radiotherapy altered the enamel's elastic modulus and its chemical composition.


Subject(s)
Humans , Cariostatic Agents/pharmacology , Fluorides, Topical/pharmacology , Tooth Demineralization/prevention & control , Dental Enamel/drug effects , Radiotherapy/adverse effects , Reference Values , Surface Properties , Microscopy, Electron, Scanning , Cariostatic Agents/radiation effects , Cariostatic Agents/chemistry , Random Allocation , Fluorides, Topical/radiation effects , Fluorides, Topical/chemistry , Reproducibility of Results , Analysis of Variance , Tooth Demineralization/etiology , Spectroscopy, Fourier Transform Infrared , Dental Enamel/radiation effects , Elastic Modulus , Hardness Tests , Hydrogen-Ion Concentration
8.
J. appl. oral sci ; 26: e20170222, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893701

ABSTRACT

Abstract The effect of fluoride agents on the retention of orthodontic brackets to enamel under erosive challenge is little investigated. Objective: The aim of this study was to evaluate the effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) agents on the shear bond strength of brackets to enamel and on the enamel microhardness around brackets under erosive challenge. Methods: Brackets were bonded to bovine incisors. Five groups were formed according to fluoride application (n=10): TiF4 varnish, TiF4 solution, NaF varnish, NaF solution and control (without application). The specimens were submitted to erosive challenge (90 s cola drink/2h artificial saliva, 4x per day for 7 days). Solutions were applied before each erosive cycle and varnishes were applied once. Vickers Microhardness (VHN) was obtained before and after all cycles of erosion and the percentage of microhardness loss was calculated. Shear bond strength, adhesive remnant index and polarized light microscopy were conducted after erosion. The data were analyzed by ANOVA, Tukey, Kruskal-Wallis and Mann-Whitney U tests (α=0.05). Results: The %VHN had no statistically significant differences among the experimental groups. However, considering the comparisons of all groups with the control group, TiF4 varnish showed the highest protection from enamel demineralization (effect size of 2.94, while the effect size for the other groups was >2.4). The TiF4 varnish group had significantly higher shear bond strength compared to other groups. There was no difference among groups for adhesive remnant index. Polarized light microscopy showed higher demineralization depth for the control group. Conclusions: Application of NaF and TiF4 agents during mild erosive challenge minimized the enamel mineral loss around brackets, however only the experimental TiF4 varnish was able to prevent the reduction of shear bond strength of brackets to enamel.


Subject(s)
Animals , Cattle , Sodium Fluoride/chemistry , Titanium/chemistry , Tooth Erosion/prevention & control , Cariostatic Agents/chemistry , Dental Bonding/methods , Orthodontic Brackets , Dental Enamel/drug effects , Fluorides/chemistry , Reference Values , Saliva, Artificial/chemistry , Surface Properties , Materials Testing , Reproducibility of Results , Analysis of Variance , Tooth Demineralization/prevention & control , Statistics, Nonparametric , Dental Enamel/chemistry , Shear Strength , Hardness Tests , Microscopy, Polarization
9.
Bauru; s.n; 2018. 132 p. tab, graf, ilus.
Thesis in English | LILACS, BBO | ID: biblio-906807

ABSTRACT

The objective of this study was to evaluate the antimicrobial and anti-caries effects of two plant extracts. The first chapter dealt with a review of the literature whose objective was to discuss the antimicrobial potential of Brazilian natural agents on the biofilm related to dental caries and gingivitis/periodontal disease. The research of the articles was carried out using PubMed. We found a total of 23 papers. Most of the studies were performed using planktonic microorganisms or under clinical trials. Nineteen articles were focused on cariogenic bacteria. From these nineteen articles, eleven were also about periodontopathogenic bacteria. Four studies addressed only periodontopathogenic bacteria. The most tested Brazilian natural agents were green propolis, essential oils of Lippia sidoides and Copaifera sp. Most of the tested agents showed similar results when compared to positive control (essential oils and extracts) or better effect than negative control (green propolis). More studies involving protocols closer to the clinical condition and the use of response variables that allows understanding the mechanism of action of natural agents are necessary before the incorporation of these natural agents into dental products. The second chapter aimed to test the effect of the hydroalcoholic extracts of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves on the viability of the microcosm biofilm and on the prevention of enamel demineralization. The microcosm biofilm was produced on bovine enamel, using human saliva pool mixed with McBain saliva (0.2% sucrose) for 14 days. The biofilm was treated daily with the extracts for 1 min. M. urundeuva at 100, 10 and 0.1 µg/ml and Q. grandiflora at 100 and 0.1 µg/ml reduced cell viability similarly to the positive control and significantly more than negative control. M. urundeuva at 1000, 100 and 0.1 µg/ml were able to reduce the counting formation unit-CFU counting of lactobacilli sp. and Streptococcus mutans, while Q. grandiflora at 1000 and 1.0 µg/ml significantly reduced the S. mutans CFU counting. On the other hand, the natural extracts did not reduce the production of extracellular polyssacharides, lactic acid and the development of enamel caries lesions. The third chapter aimed to evaluate the effect of hydroalcoholic extracts of M. urundeuva and Q. grandiflora (alone or combined) on the viability of S. mutans biofilm and the prevention of enamel demineralization. S. mutans strain (ATCC 21175) was reactivated in BHI broth. Minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration and minimum biofilm eradication concentration were determined to choose the concentrations to be tested under the biofilm model. S. mutans biofilm (5x105 CFU/ml) was produced on bovine enamel using McBain saliva with 0.2% sucrose for 3 days. The biofilm was treated daily with the extracts for 1 min. M. urundeuva (isolated or combined) at concentrations equal or higher than 0.625 mg/ml was able to reduce the bacteria viability, whereas Q. grandiflora extract alone showed antimicrobial effect at 5 mg/ml only (p<0.05). On the other hand, none of the extracts was able to reduce the development of enamel caries lesions. Despite the tested natural extracts have antimicrobial effect; they are unable to prevent caries in enamel.(AU)


O objetivo foi avaliar os efeitos antimicrobiano e anti-cárie de dois extratos de plantas. O primeiro capítulo se referiu a uma revisão da literatura cujo objetivo foi discutir o potencial antimicrobiano dos agentes naturais brasileiros sobre o biofilme relacionado à cárie dentária e à gengivite/doença periodontal. A pesquisa dos artigos foi realizada usando o PubMed. Foram encontrados 23 trabalhos. A maioria dos estudos foi realizada utilizando microorganismos na fase planctônica ou ensaios clínicos. Dezenove artigos foram focados em bactérias cariogênicas. Dos dezenove artigos, onze também eram sobre bactérias periodontopatogênicas. Quatro estudos abordaram apenas bactérias periodontopatogênicas. Os agentes naturais brasileiros mais testados foram própolis verde, óleos essenciais de Lippia sidoides e Copaifera sp. Os agentes testados apresentaram resultados similares quando comparados ao controle positivo (óleos essenciais e extratos) ou melhor efeito que o controle negativo (própolis verde). Mais estudos próximos da condição clínica e o uso de variáveis de resposta que permitam entender o mecanismo de ação são necessários, para permitir a incorporação desses agentes naturais em produtos odontológicos. O segundo capítulo teve como objetivo testar o efeito dos extratos hidroalcoólicos de Myracrodruon urundeuva All. e Qualea grandiflora Mart. sobre a viabilidade do biofilme microcosmo e na prevenção da desmineralização do esmalte. O biofilme microcosmo foi produzido em esmalte bovino, utilizando pool de saliva humana misturada à saliva de McBain (0,2% de sacarose) durante 14 dias. O biofilme foi tratado diariamente com os extratos durante 1 min. M. urundeuva a 100, 10 e 0,1 µg/ml e Q. grandiflora a 100 e 0,1 µg/ml reduziram a viabilidade dos microrganismos de forma semelhante ao controle positivo e significativamente maior do que o controle negativo. M. urundeuva a 1000, 100 e 0,1 µg/ml foi capaz de reduzir a contagem de Unidade formadora de colônia-UFC para Lactobacilos totais e Streptococcus mutans, enquanto a Q. grandiflora a 1000 e 1,0 µg/ml reduziu significativamente a contagem de UFC para S. mutans. Os extratos naturais não conseguiram reduzir a produção de polissacarídeos extracelulares-PEC, ácido lático e o desenvolvimento da lesão cariosa em esmalte. O terceiro capítulo teve como objetivo avaliar o efeito dos extratos hidroalcoólicos de M. urundeuva. e Q. grandiflora (sozinhos ou combinados) sobre a viabilidade do biofilme de S. mutans e na prevenção da desmineralização do esmalte. Cepa de S. mutans (ATCC 21175) foi reativada em caldo BHI. Concentração inibitória mínima, concentração bactericida mínima, concentração inibitória mínima de biofilme e concentração de erradicação mínima de biofilme foram determinadas para escolher as concentrações a serem testadas sob o modelo de biofilme. O biofilme de S. mutans (5x105 CFU/ml) foi produzido em esmalte bovino, utilizando saliva de McBain com 0,2% de sacarose durante 3 dias. O biofilme foi tratado diariamente com os extratos durante 1 min. M. urundeuva (isolada ou combinada) nas concentrações iguais ou superiores a 0,625 mg/ml foi capaz de reduzir a viabilidade das bactérias, enquanto que o extrato da Q. grandflora apresentou efeito antimicrobiano somente a 5 mg/ml (p<0,05). Nenhum dos extratos reduziu o desenvolvimento da lesão da cárie. Apesar dos extratos naturais terem efeito antimicrobiano, são incapazes de prevenir o desenvolvimento da lesão cariosa em esmalte.(AU)


Subject(s)
Humans , Animals , Cattle , Anacardiaceae/chemistry , Anti-Infective Agents/pharmacology , Biofilms/drug effects , Dental Enamel/microbiology , Magnoliopsida/chemistry , Plant Extracts/pharmacology , Tooth Demineralization/prevention & control , Microbial Sensitivity Tests , Microradiography , Reproducibility of Results , Saliva/microbiology , Streptococcus mutans/drug effects , Streptococcus mutans/growth & development , Time Factors
10.
Int. j. odontostomatol. (Print) ; 11(3): 247-251, set. 2017. tab
Article in Spanish | LILACS | ID: biblio-893258

ABSTRACT

RESUMEN: Hipomineralización Molar-Incisal (MIH) es un trastorno del desarrollo dentario asociado a factores sistémicos, producido por una incompleta mineralización y maduración del esmalte. La prevalencia en niños, a nivel mundial, varía en la literatura entre el 2,4 % y el 40,2 %. Este trastorno que implica al menos un primer molar permanente, pudiendo también verse afectados los incisivos, dependiendo del momento, la duración, la susceptibilidad del individuo y la gravedad de la injuria prenatal, perinatal o postnatal. El esmalte presenta un grado variable de alteración en la translucidez, siendo éste de un espesor normal y de color blanco, o café-amarillo. Si bien se encuentra intacto en el momento de la erupción, puede sufrir fracturas post eruptivas debido a las fuerzas de la masticación, dejando límites definidos. Por lo general, los molares gravemente afectados son extremadamente hipersensibles, propensos a lesiones de caries de rápida progresión, y pueden ser difíciles de tratar en pacientes jóvenes. La atención debe abordar el comportamiento y la ansiedad del niño, con el objetivo de proporcionar restauraciones duraderas en condiciones libres de dolor. La ejecución de medidas preventivas individuales puede posponer el inicio del tratamiento restaurador y reducir la incomodidad del paciente a largo plazo. El diagnóstico precoz permitirá el seguimiento y la instauración de dichas medidas preventivas tan pronto las superficies afectadas sean accesibles. Pese a que los enfoques de tratamiento para MIH han comenzado a ser más claros y los avances en los materiales dentales han proporcionado soluciones clínicas en los casos que se consideraban sin posibilidad de restauración en el pasado, deben llevarse a cabo ensayos clínicos a largo plazo para facilitar aún más el manejo clínico de este cuadro.


ABSTRACT: Molar Incisor Hypomineralization (MIH) is a tooth development disorder, which is associated with systemic factors, produced by incomplete enamel mineralization and maturation below the enamel surface that is intact at the time of eruption. In literature, the prevalence in children worldwide varies between 2.4 % and 40.2 %. This disorder which involves at least one first permanent molar, and depending on duration, the child's susceptibility as well as the severity of prenatal, perinatal or postnatal insult may also compromise incisors. The defect reveals a variable degree of alteration in the translucency of the enamel, that has initially normal thickness and can be white, yellow or brown. Enamel surface may breakdown after eruption, due to masticatory forces, leaving sharp borders. Usually, severely affected molars are extremely hypersensitive, prone to rapid caries development, and can be difficult to manage in young patients. The complex care involved must address the child's behavior and anxiety, aiming to provide pain free treatment and durable restorations. Intensive individually prescribed preventive programs may postpone the onset of restorative treatment and reduce patient discomfort in the long term. Early identification of such children will allow monitoring and implementation of preventive measures as soon as affected surfaces are accessible. Although treatment approaches for MIH have become more clear, and advances in dental materials have provided clinical solutions in cases that in the past were regarded as unrestorable, long-term clinical trials should be realized to further facilitate clinical management of this dental defect.


Subject(s)
Humans , Tooth Demineralization/pathology , Tooth Demineralization/prevention & control , Tooth Demineralization/therapy , Dental Enamel/abnormalities
11.
J. appl. oral sci ; 25(4): 420-426, July-Aug. 2017. tab, graf
Article in English | LILACS, BBO | ID: biblio-893644

ABSTRACT

Abstract Objective The prevalence of dental erosion has been recently increasing, requiring new preventive and therapeutic approaches. Vegetable oils have been studied in preventive dentistry because they come from a natural, edible, low-cost, and worldwide accessible source. This study aimed to evaluate the protective effect of different vegetable oils, applied in two concentrations, on initial enamel erosion. Material and Methods Initially, the acquired pellicle was formed in situ for 2 hours. Subsequently, the enamel blocks were treated in vitro according to the study group (n=12/per group): GP5 and GP100 - 5% and pure palm oil, respectively; GC5 and GC100 - 5% and pure coconut oil; GSa5 and GSa100 - 5% and pure safflower oil; GSu5 and GSu100 - 5% and pure sunflower oil; GO5 and GO100 - 5% and pure olive oil; CON− - Deionized Water (negative control) and CON+ - Commercial Mouthwash (Elmex® Erosion Protection Dental Rinse, GABA/positive control). Then, the enamel blocks were immersed in artificial saliva for 2 minutes and subjected to short-term acid exposure in 0.5% citric acid, pH 2.4, for 30 seconds, to promote enamel surface softening. The response variable was the percentage of surface hardness loss [((SHi - SHf) / SHf )×100]. Data were analyzed by one-way ANOVA and Tukey's test (p<0.05). Results Enamel blocks of GP100 presented similar hardness loss to GSu100 (p>0.05) and less than the other groups (p<0.05). There was no difference between GP5, GC5, GC100, GSa5, GSu100, GSa100, GSu5, GO5, GO100, CON− and CON+. Conclusion Palm oil seems to be a promising alternative for preventing enamel erosion. However, further studies are necessary to evaluate a long-term erosive cycling.


Subject(s)
Humans , Young Adult , Tooth Erosion/prevention & control , Plant Oils/therapeutic use , Dental Pellicle/drug effects , Saliva/chemistry , Saliva, Artificial , Surface Properties , Time Factors , Materials Testing , Plant Oils/pharmacology , Random Allocation , Palm Oil , Reproducibility of Results , Treatment Outcome , Tooth Demineralization/prevention & control , Hardness Tests
12.
Braz. oral res. (Online) ; 31: e86, 2017. tab, graf
Article in English | LILACS | ID: biblio-952118

ABSTRACT

Abstract The effect of a 4% titanium tetrafluoride (TiF 4 ) varnish on enamel demineralization was evaluated. Twelve volunteers participated in this double-blind, randomized crossover study. Six enamel specimens were positioned in intraoral appliances throughout four treatment stages: 4% TiF 4 varnish (experimental varnish), 5% sodium fluoride (NaF) varnish (Duraphat ® ), placebo varnish, and negative control (deionized water). After 24 h, the varnishes were removed and plaques were allowed to accumulate. A 20% sucrose solution was dripped onto enamel blocks (10x/day). Enamel alterations were analyzed by surface microhardness (SMH), percentage of surface loss (%SML), cross-sectional microhardness (CSMH), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS). Student's paired t-test was used for SMH analysis and repeated-measures analysis of variance (ANOVA) for %SML and CSMH (∆Z) analyses (p-value=0.05). The TiF 4 varnish group had lower %SML than the placebo and control groups (p=0.044 and p=0.003, respectively), thus showing its capacity to inhibit surface demineralization. TiF 4 and NaF varnishes demonstrated a protective effect against mineral loss on the enamel subsurface. Both were statistically different from the control group when CSMH was analyzed (p=0.000). A titanium dioxide film was observed on enamel surfaces of the TiF 4 group SEM images. EDS confirmed the presence of titanium in all TiF 4 samples. The 4% TiF 4 varnish is a promising compound capable of reacting with enamel to protect it against surface and subsurface demineralization.


Subject(s)
Humans , Adult , Young Adult , Sodium Fluoride/pharmacology , Titanium/pharmacology , Cariostatic Agents/pharmacology , Tooth Demineralization/prevention & control , Dental Enamel/drug effects , Fluorides/pharmacology , Spectrometry, X-Ray Emission , Surface Properties , Time Factors , Materials Testing , Microscopy, Electron, Scanning , Double-Blind Method , Fluorides, Topical/pharmacology , Reproducibility of Results , Analysis of Variance , Treatment Outcome , Statistics, Nonparametric , Cross-Over Studies , Dental Enamel/surgery , Hardness Tests
13.
Bauru; s.n; 2017. 99 p. ilus, tab, graf.
Thesis in English | LILACS, BBO | ID: biblio-883780

ABSTRACT

This study aimed to answer the following questions: 1) does whole fluoridated milk protect more against enamel and dentin erosion than fat-free fluoridated milk? 2) does the protective effect of fluoridated milk against erosion follow a dose-response relationship? 3) is the treatment with whole or fat-free fluoridated milk before the first erosive challenge more protective against enamel and dentin erosion? 4) does the fat content of milk change the proteomic profile of the acquired enamel pellicle (AEP)? This study was divided into 2 parts. The first part analyzed in vitro the effect of milk against dental erosion, considering three factors: type of bovine milk (whole/fat-free), presence of different fluoride concentrations (0- 10.0 ppm) and time of application (before/after erosive challenge). Bovine enamel (n=15/group) and root dentin (n=12/group) specimens were submitted to the following treatments: 0.9% NaCl solution (negative control)( after first erosive challenge); whole milk with 0, 2.5, 5.0, 10.0 ppm F; fat-free milk with 0, 2.5, 5.0, 10.0 ppm F; 0.05% NaF solution (positive control) (before or after first erosive challenge). Specimens were submitted to demineralization - remineralization regimes, 4 times/ day, for 5 days. The response variables were enamel and dentin loss, evaluated by profilometry (µm). Data were analyzed using Kruskal­Wallis/Dunn's test (p<0.05). The presence of fluoride, especially at 10 ppm, was the most important factor in reducing dental erosion. The second part detected changes in protein profile of AEP formed in vivo after rinsing with whole milk, fat-free milk or water. Nine subjects with good oral conditions participated. The AEP was formed in the morning, for 120 min, after prophylaxis with pumice. In sequence, the volunteers rinsed with 10 mL of whole milk, fat-free milk or deionized water for 30 s, following a blind, crossover protocol. After 60 min, the AEP was collected with filter paper soaked in 3% citric acid and processed for analysis by liquid chromatography-electrospray ionization tandem mass spectrometry (LCESI- MS/MS). The obtained MS/MS spectra were searched against human protein database (SWISS­PROT). The proteomic data related to protein quantification were analyzed using the PLGS software. A total of 260 proteins were successfully identified in the AEP samples collected in all groups. Forty-nine were common to the 3 groups, while 72, 62 and 49 were specific for groups treated with whole milk, fat-free milk and water, respectively. Some were typical components of the AEP, such as Cystatin-B, Lysozyme C, Histatin-1, Statherin and Lactotransferrin. Other proteins are not commonly described as part of the AEP but could act in the defense of the organism against pathogens. Distinct proteomic profiles were found in the AEP after rinsing with whole or fat-free milk, which could have an impact in bacterial adhesion and tooth dissolution. The use of fat-free milk could favorably modulate the adhesion of bacteria in the AEP and the biofilm formation in comparison to whole milk.(AU)


Este estudo objetivou responder as seguintes questões: 1) o leite integral fluoretado protege mais contra a erosão do esmalte e dentina do que o leite fluoretado desnatado? 2) o efeito protetor do leite fluoretado segue um padrão dose-resposta? 3) o tratamento com leite integral ou leite desnatado fluoretado antes do primeiro desafio erosivo protege mais contra a erosão do esmalte e dentina? 4) o leite contendo gordura altera o perfil proteico da película adquirida do esmalte (PAE)? O estudo foi dividido em 2 partes. Na primeira parte foi realizado um estudo in vitro, considerando três fatores: tipo de leite bovino (integral/ desnatado), diferentes concentrações de fluoreto e tempo de aplicação (antes/após desafio erosivo). Os espécimes de esmalte bovino (n=15 /grupo) e dentina radicular (n=12 /grupo) foram submetidos aos seguintes tratamentos: solução de NaCl a 0,9% (controle negativo)(após o desafio erosivo); Leite integral com 0, 2,5, 5,0, 10,0 ppm F Leite desnatado com 0, 2,5, 5,0, 10,0 ppm F 0,05% de solução de NaF (controle positivo) (antes ou após o primeiro desafio erosivo). Os espécimes foram submetidos a regimes de desmineralização e remineralização, 4 vezes/dia, durante 5 dias. As variáveis de resposta foram perda de esmalte e dentina, avaliadas por perfilometria (µm). Os dados foram analisados usando o teste de Kruskal-Wallis / Dunn (p <0,05). A presença de fluoreto, especialmente na concentração de 10 ppm, demonstrou ser o fator mais importante na redução da erosão dentária. A parte II do estudo detectou alterações no perfil proteico da PAE formada in vivo após bochecho com leite integral, leite desnatado ou água. Nove indivíduos com boas condições de saúde bucal participaram. A PAE foi formada pela manhã, durante 120 minutos, após profilaxia com pedra-pomes. Em seguida, os voluntários bochecharam com 10 mL de leite integral, leite desnatado ou água deionizada durante 30 s, seguindo um protocolo cego e cruzado. Após 60 min, a película foi coletada com papel de filtro embebido em ácido cítrico a 3% e processada para análise por cromatografia líquida acoplada à espectrometria de massas com ionização por eletrospray (LC-ESI-MS / MS). Os espectros MS/MS obtidos foram confrontados com bases de dados de proteínas humanas (SWISSPROT). Os dados proteômicos relacionados à quantificação de proteínas foram analisados usando o software PLGS. Um total de 260 proteínas foi identificado nas amostras de PAE coletadas em todos os grupos. Quarenta e nove eram comuns aos 3 grupos, enquanto 72, 62 e 49 eram específicas para grupos tratados com leite integral, leite desnatado e água, respectivamente. Algumas proteínas encontradas são típicas da PAE, como Cistatina-B, Lisozima C, Histatina-1, Estaterina e Lactotransferrina. Outras proteínas não são comumente descritas como parte da PAE, mas podem atuar na defesa do organismo contra patógenos. Perfis proteômicos distintos foram encontrados na PAE após o bochecho com leite integral ou desnatado, o que poderia ter um impacto na adesão bacteriana e na dissolução dentária. O uso de leite desnatado pode modular favoravelmente a adesão de bactérias na PAE e a formação do biofilme em comparação com o leite integral.(AU)


Subject(s)
Humans , Animals , Cattle , Cariostatic Agents/chemistry , Fluorides/chemistry , Milk/chemistry , Protective Agents/chemistry , Tooth Demineralization/prevention & control , Dental Enamel/drug effects , Dentin/drug effects , Proteins/analysis , Proteomics , Reproducibility of Results , Time Factors
14.
Bauru; s.n; 2016. 122 p. tab, ilus.
Thesis in Portuguese | LILACS, BBO | ID: biblio-882194

ABSTRACT

O objetivo foi comparar uma formulação de saliva artificial com e sem mucina (in vitro) com a saliva humana (in situ) na inibição da desmineralização (subprojeto I) e no reendurecimeto de lesões de erosão (subprojeto II), e a influência do tipo de dispositivo intrabucal (mandibular X palatino) no desgaste erosivo do esmalte (subprojeto III). No subprojeto I, blocos de esmalte bovino foram selecionados pela dureza de superfície e randomizados entre os grupos: GI - saliva humana (n=30), GII - saliva artificial sem mucina (n=15), GIII - saliva artificial com mucina (n=15) e GIV - água deionizada (n=15). Quinze voluntários utilizaram o dispositivo palatino por um período 2 horas (GI). Nos grupos GII, GIII e GIV, os blocos foram imersos em suas respectivas soluções por um período de 2 horas. Imediatamente após, tanto os blocos do grupo in situ quanto dos grupos in vitro foram submetidos ao desafio erosivo inicial com ácido cítrico 1% (pH 3,6) por 4 minutos. A microdureza final foi mensurada para determinar a porcentagem de perda de dureza. No subprojeto II, os blocos, após seleção, foram erodidos in vitro e randomizados entre grupos como no subprojeto I. Para a erosão, os blocos foram imersos em ácido cítrico 1% (pH 3,6) por 4 minutos. A seguir, no grupo GI, 15 voluntários utilizaram dispositivos palatinos durante 2 horas. Nos outros grupos os blocos foram imersos nas salivas artificiais com (GIII) e sem mucina (GII) e água deionizada (GIV) por 2 horas. A precipitação de minerais sobre o esmalte foi avaliada por meio da porcentagem de recuperação de dureza. No subprojeto III, após seleção dos blocos pela dureza, os mesmos foram aleatorizados em 2 grupos (n=20): GI - dispositivo palatino e GII - dispositivo mandibular. A ciclagem consistiu na imersão dos dois dispositivos em ácido clorídrico 0,01 M (pH 2,3) por 2 minutos, 4X/dia durante 5 dias. A perda do esmalte foi avaliada por perfilometria e os voluntários responderam a um questionário quanto ao conforto dos dispositivos. Nos subprojetos I e II, os dados foram submetidos aos testes ANOVA e Tukey e no subprojeto III foi aplicado o Teste T pareado (p<0,05). Nos subprojetos I e II observou-se que todas as salivas estudadas foram capazes de promover uma recuperação de dureza do esmalte e nenhuma diferença foi encontrada entre elas (p<0,05). No ensaio de desmineralização, a saliva artificial com mucina e a saliva humana (in situ) promoveram menor perda de dureza, não mostrando diferença entre elas (p<0,05). No subprojeto III os resultados mostraram que os blocos localizados no dispositivo palatino (GI) apresentaram maior desgaste erosivo quando comparados aos do dispositivo mandibular (GII). Além disso, todos voluntários relataram maior conforto no uso do dispositivo palatino. Considerando que o dispositivo palatino é mais confortável e resultou em maior perda de esmalte quando comparado ao mandibular, sugere-se o uso de dispositivos palatinos em protocolos in situ que queiram mimetizar pacientes com alto risco de erosão dentária. Para estudos in vitro, a saliva com mucina mostrou-se como uma boa substituta à saliva humana.(AU)


The aim was to compare artificial saliva formulation with and without mucin (in vitro) with human saliva (in situ) on the inhibition of erosive demineralization (subproject I) and on the rehardening of erosion lesions (subproject II), and analyze the influence of the type of intraoral appliance (mandibular X maxillary) in enamel wear caused by erosive challenges (subproject III). In the subproject I, bovine enamel blocks were selected by initial surface hardness and randomized among the groups: GI - human saliva (n=30), GII - artificial saliva without mucin (n=15), GIII - artificial saliva with mucin (n=15) and GIV - deionized water (n=15). Fifteen volunteers wore palatal appliances for 2 hours (GI). In the GII, GIII and GIV groups, the blocks were immersed to the respective solutions for 2 hours. Subsequently, both in vitro and in situ blocks were subjected to initial erosive challenge in 1% citric acid (pH 3.6) for 4 minutes. Final enamel hardness was measured to determine the protective capacity of saliva tested by percentage of hardness loss. For the subproject II, after blocks selection, they were in vitro eroded and randomly among the groups as in subproject I. For erosion, the enamel blocks were immersed on 1% citric acid (pH 3.6) for 4 minutes. Then, in the GI, 15 volunteers wore palatal appliances for 2 hours. In the other groups the blocks were immersed in artificial saliva with (GIII) and without mucin (GII) and deionized water (GIV) for 2 hours. The minerals precipitation on the enamel was evaluated by the percentage of hardness recovery. On subproject III, after enamel blocks selection by surface hardness, they were randomly divided into 2 groups (n=20): GI - palatine appliance and GII - mandibular appliance. Erosive cycling consists in immersing of both devices in 0.01 M hydrochloric acid (pH 2.3) for 2 minutes, 4X/day during 5 days. The analysis of the wear was measured by profilometry and volunteers answered a questionnaire about the comfort of the devices. In the subprojects I and II, data were analyzed by one-way ANOVA and Tukeys test, and in the subproject III It was applied paired t-test (p <0.05). In subprojects I and II it was observed that all studied saliva promoted enamel rehardening and no difference was found between them (p <0.05). In the demineralization test, the artificial saliva with mucin and human saliva (in situ) provided lower enamel hardness loss, showing no difference between them (p<0.05). In the subproject III, the results showed that the specimens allocated in palatine appliance (GI) presented significantly higher erosive wear when compared to the specimens fixed in mandibular appliance (GII). In addition, all volunteers reported greater comfort in using the palatal device. Considering the palatal device is more comfortable and resulted in higher enamel loss when compared to the mandibular device, it is suggested the use of palatine appliances in in situ protocols who want to mimic a patient at high risk of dental erosion. For in vitro studies, the saliva with mucin might be a good substitute for human saliva.(AU)


Subject(s)
Humans , Animals , Male , Female , Adolescent , Adult , Cattle , Dental Enamel/chemistry , Mucins/chemistry , Saliva, Artificial/chemistry , Saliva/chemistry , Tooth Demineralization/prevention & control , Tooth Erosion/prevention & control , Analysis of Variance , Dental Models , Hardness Tests , Reproducibility of Results , Surface Properties
15.
J. appl. oral sci ; 23(3): 302-309, May-Jun/2015. graf
Article in English | LILACS, BBO | ID: lil-752425

ABSTRACT

Dental caries is considered a disease of high prevalence and a constant problem in public health. Proanthocyanidins (PAs) are substances that have been the target of recent studies aiming to control or treat caries. Objective The aim of this in vitro study was to evaluate the efficacy of a treatment with grape seed extract, under cariogenic challenge, to minimize or even prevent the onset of caries in the enamel and dentin. Material and Methods Blocks of enamel and dentin (6.0x6.0 mm) were obtained from bovine central incisors, polished, and selected by analysis of surface microhardness (SH). The blocks were randomly divided into 3 groups (n=15), according to the following treatments: GC (control), GSE (grape seed extract), GF (fluoride – 1,000 ppm). The blocks were subjected to 6 daily pH cycles for 8 days. Within the daily cycling, the specimens were stored in buffered solution. The blocks were then analyzed for perpendicular and surface hardness and polarized light microscopy. Results The means were subjected to statistical analysis using the ANOVA and Fisher's PLSD tests (p<0.05). For enamel SH, GF showed the highest hardness values. In the dentin, GF was also the one that showed higher hardness values, followed by GSE. Regarding the cross-sectional hardness values, all groups behaved similarly in both the enamel and dentin. The samples that were treated with GSE and fluoride (GF) showed statistically higher values than the control. Conclusion Based on the data obtained in this in vitro study, it is suggested that grape seed extract inhibits demineralization of artificial carious lesions in both the enamel and dentin, but in a different scale in each structure and in a smaller scale when compared to fluoride. .


Subject(s)
Animals , Cattle , Dental Caries/prevention & control , Dental Enamel/drug effects , Dentin/drug effects , Grape Seed Extract/chemistry , Proanthocyanidins/pharmacology , Tooth Demineralization/prevention & control , Hardness Tests , Hydrogen-Ion Concentration , Microscopy, Polarization , Random Allocation , Reproducibility of Results , Surface Properties , Time Factors , Tooth Remineralization
16.
Bauru; s.n; 2015. 182 p. ilus, tab, graf.
Thesis in Portuguese | LILACS, BBO | ID: biblio-867339

ABSTRACT

Este estudo teve como o objetivo avaliar in vitro o efeito do tratamento com vernizes de tetrafluoreto de titânio (TiF4) e fluoreto de sódio (NaF) (ambos com 0,95%, 1,95% e 2,45% F) sobre 1) a quantidade de F- liberada em água deionizada e saliva artificial, por período de 12h; 2) os tipos de compostos formados pela interação com a hidroxiapatita (neste caso, com soluções ao invés dos vernizes); 3) a porcentagem de elementos presentes na superfície do esmalte bovino e humano, hígidos (H) e desmineralizados (DES); 4) a quantidade de CaF2 sobre a superfície do esmalte bovino e humano, H e DES. Adicionalmente, 5) o efeito dos vernizes de TiF4 e NaF sobre a remineralização do esmalte bovino, em diferentes condições in situ, foi avaliado. Para etapa 1, a liberação de F- foi quantificada por eletrodo de íon específico. Na etapa 2, pó de HAP produzido por precipitação foi tratado com soluções fluoretadas. Os compostos formados foram avaliados por espectroscopia de infravermelho e difração de raios-X. Nas etapas 3 e 4, as superfícies tratadas com os vernizes foram analisadas por MEV- EDAX e por biópsias básicas, respectivamente. Vinte voluntários (n final=17) participaram do ensaio in situ com 3 fases cruzadas, os quais utilizaram aparelhos palatinos contendo amostras de esmalte bovino desmineralizadas tratadas com vernizes de TiF4, NaF ou placebo. As amostras foram submetidas a diferentes condições de des-remineralização (presença ou não de tela plástica; variação da frequência de aplicação de sacarose 20%) e à exposição ao dentifrício fluoretado. O volume mineral e profundidade da lesão foram avaliados por microradiografia transversal (TMR). 1) Os vernizes de TiF4 (1,95 e 2,45% F) liberaram mais fluoreto comparados aos vernizes de NaF tanto em água como em saliva artificial, sendo a diferença significativa nas primeiras 6h de contato (p<0,0001). 2) O TiF4 causou alteração na estrutura da HAP e induziu à formação de novos compostos como TiO2 e Ti (HPO4)2. 3)...


This study aimed to evaluate the in vitro effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) varnishes (both with 0.95%, 1.95%, 2.45% F) treatment on the 1) F- release in deionized water and artificial saliva for 12h period; 2) types of compounds formed by the interaction with hydroxyapatite (in this case, solutions were tested instead of varnishes); 3) percentage of the elements on bovine and human, sound (S) and demineralized (DE), enamel surface; 4) F- uptake (CaF2 deposition) on human and bovine, S and DE, enamel surface. Additionally, 5) the effect of TiF4 and NaF varnishes on bovine enamel remineralization, in different in situ conditions, was assessed. In study 1, the F- release was measured by ion specific electrode. In study 2, HAP powder, produced by precipitation, was treated with fluoride solutions. The compounds formed were evaluated by infrared spectroscopy and X-ray diffraction. In studies 3 and 4, the surfaces treated with the varnishes were analyzed by SEM-EDAX and basic biopsies, respectively. Twenty volunteers (final n=17) participated of the in situ study with 3 crossover phases, in which they wore palatal appliances containing bovine demineralized enamel samples treated with TiF4, NaF or placebo varnishes. The samples were subjected to different de-remineralization conditions (presence or absence of plastic mesh and variation in frequency of application of 20% sucrose) and exposure to fluoride dentifrice. Themineral content and lesion depth were evaluated by transverse microradiography (TMR). 1) The TiF4 varnishes (1.95 and 2.45% F) released more F- compared to NaF varnishes in both water and artificial saliva, and significant difference was found in the first 6h (p<0.0001). 2) The TiF4 caused change in the HAP structure and induced the formation of new compounds such as TiO2 and Ti (HPO4)2. 3) The TiF4 varnishes induced the formation of a coating layer rich in Ti and F, with microcracks in its extension, on the enamel...


Subject(s)
Humans , Animals , Cattle , Dental Caries/prevention & control , Tooth Demineralization/prevention & control , Dental Enamel , Fluorides, Topical/chemistry , Hydroxyapatites/chemistry , Titanium/chemistry , Cariostatic Agents/chemistry , Sodium Fluoride/chemistry , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Saliva, Artificial/chemistry
17.
Bauru; s.n; 2015. 182 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: lil-773791

ABSTRACT

Este estudo teve como o objetivo avaliar in vitro o efeito do tratamento com vernizes de tetrafluoreto de titânio (TiF4) e fluoreto de sódio (NaF) (ambos com 0,95%, 1,95% e 2,45% F) sobre 1) a quantidade de F- liberada em água deionizada e saliva artificial, por período de 12h; 2) os tipos de compostos formados pela interação com a hidroxiapatita (neste caso, com soluções ao invés dos vernizes); 3) a porcentagem de elementos presentes na superfície do esmalte bovino e humano, hígidos (H) e desmineralizados (DES); 4) a quantidade de CaF2 sobre a superfície do esmalte bovino e humano, H e DES. Adicionalmente, 5) o efeito dos vernizes de TiF4 e NaF sobre a remineralização do esmalte bovino, em diferentes condições in situ, foi avaliado. Para etapa 1, a liberação de F- foi quantificada por eletrodo de íon específico. Na etapa 2, pó de HAP produzido por precipitação foi tratado com soluções fluoretadas. Os compostos formados foram avaliados por espectroscopia de infravermelho e difração de raios-X. Nas etapas 3 e 4, as superfícies tratadas com os vernizes foram analisadas por MEV- EDAX e por biópsias básicas, respectivamente. Vinte voluntários (n final=17) participaram do ensaio in situ com 3 fases cruzadas, os quais utilizaram aparelhos palatinos contendo amostras de esmalte bovino desmineralizadas tratadas com vernizes de TiF4, NaF ou placebo. As amostras foram submetidas a diferentes condições de des-remineralização (presença ou não de tela plástica; variação da frequência de aplicação de sacarose 20%) e à exposição ao dentifrício fluoretado. O volume mineral e profundidade da lesão foram avaliados por microradiografia transversal (TMR). 1) Os vernizes de TiF4 (1,95 e 2,45% F) liberaram mais fluoreto comparados aos vernizes de NaF tanto em água como em saliva artificial, sendo a diferença significativa nas primeiras 6h de contato (p<0,0001). 2) O TiF4 causou alteração na estrutura da HAP e induziu à formação de novos compostos como TiO2 e Ti (HPO4)2. 3)...


This study aimed to evaluate the in vitro effect of titanium tetrafluoride (TiF4) and sodium fluoride (NaF) varnishes (both with 0.95%, 1.95%, 2.45% F) treatment on the 1) F- release in deionized water and artificial saliva for 12h period; 2) types of compounds formed by the interaction with hydroxyapatite (in this case, solutions were tested instead of varnishes); 3) percentage of the elements on bovine and human, sound (S) and demineralized (DE), enamel surface; 4) F- uptake (CaF2 deposition) on human and bovine, S and DE, enamel surface. Additionally, 5) the effect of TiF4 and NaF varnishes on bovine enamel remineralization, in different in situ conditions, was assessed. In study 1, the F- release was measured by ion specific electrode. In study 2, HAP powder, produced by precipitation, was treated with fluoride solutions. The compounds formed were evaluated by infrared spectroscopy and X-ray diffraction. In studies 3 and 4, the surfaces treated with the varnishes were analyzed by SEM-EDAX and basic biopsies, respectively. Twenty volunteers (final n=17) participated of the in situ study with 3 crossover phases, in which they wore palatal appliances containing bovine demineralized enamel samples treated with TiF4, NaF or placebo varnishes. The samples were subjected to different de-remineralization conditions (presence or absence of plastic mesh and variation in frequency of application of 20% sucrose) and exposure to fluoride dentifrice. Themineral content and lesion depth were evaluated by transverse microradiography (TMR). 1) The TiF4 varnishes (1.95 and 2.45% F) released more F- compared to NaF varnishes in both water and artificial saliva, and significant difference was found in the first 6h (p<0.0001). 2) The TiF4 caused change in the HAP structure and induced the formation of new compounds such as TiO2 and Ti (HPO4)2. 3) The TiF4 varnishes induced the formation of a coating layer rich in Ti and F, with microcracks in its extension, on the enamel...


Subject(s)
Humans , Animals , Cattle , Dental Caries/prevention & control , Tooth Demineralization/prevention & control , Dental Enamel , Fluorides, Topical/chemistry , Hydroxyapatites/chemistry , Titanium/chemistry , Cariostatic Agents/chemistry , Sodium Fluoride/chemistry , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Saliva, Artificial/chemistry
18.
Braz. oral res. (Online) ; 29(1): 1-6, 2015. tab, ilus
Article in English | LILACS | ID: lil-777188

ABSTRACT

The aims of this study were (1) to assess the amount of fluoride (F) released from varnishes containing calcium glycerophosphate (CaGP) and (2) to assess the effect of the experimental varnishes on in vitrodemineralization. Six test groups using 5 varnishes: base varnish (no active ingredients); Duraphat® (2.26% NaF); Duofluorid® (5.63% NaF/CaF2); experimental varnish 1 (1% CaGP/5.63% NaF/CaF2); experimental varnish 2 (5% CaGP/5.63% NaF/CaF2); and no varnish were set up. In stage 1, 60 acrylic blocks were randomly distributed into 6 groups (n = 10). Then 300 µg of each varnish was applied to each block. The blocks were immersed in deionized water, which was changed after 1, 8, 12, 24, 48 and 72 hours. Fluoride concentration in the water was analyzed using a fluoride electrode. In stage 2, 60 bovine enamel samples were distributed into 6 groups (n = 10), and treated with 300 µg of the respective varnish. After 6 h the varnish was removed and the samples were subjected to a 7-day in vitro pH cycle (6 h demineralization/18 h remineralization per day). The demineralization was measured using surface hardness. The results showed that both experimental varnishes released more fluoride than Duofluorid® and Duraphat® (p < 0.05), but Duraphat® showed the best preventive effect by decreasing enamel hardness loss (p < 0.05). Therefore, we conclude that even though (1) the experimental varnishes containing CaGP released greater amounts of F, (2) they did not increase in the preventive effect against enamel demineralization.


Subject(s)
Animals , Cattle , Cariostatic Agents/chemistry , Dental Enamel/drug effects , Fluorides, Topical/chemistry , Glycerophosphates/chemistry , Sodium Fluoride/chemistry , Tooth Demineralization/prevention & control , Dental Caries/prevention & control , Hardness Tests , Materials Testing , Random Allocation , Reference Values , Reproducibility of Results , Surface Properties , Time Factors , Water/chemistry
19.
J. appl. oral sci ; 22(5): 459-464, Sep-Oct/2014. tab
Article in English | LILACS, BBO | ID: lil-729850

ABSTRACT

The use of erbium lasers to prevent caries in enamel has shown positive results. However, it is not known if Er,Cr:YSGG laser can also be used to increase acid resistance of root dentine, which is another dental tissue susceptible to the action of cariogenic bacteria. Objective: To analyze the effects of the Er,Cr:YSGG laser (λ=2.78 μm, 20 Hz) irradiation associated with 2% neutral sodium fluoride (NaF) to prevent root dentin demineralization. Material and Methods: One hundred human root dentin samples were divided into 10 groups (G) and treated as follows: G1: no treatment; G2: NaF; G3: laser (4.64 J/cm2) with water cooling (WC=5.4 mL/min); G4: laser (4.64 J/cm2) without WC; G5: laser (8.92 J/cm2) with WC; G6: laser (8.92 J/cm2) without WC; G7: laser (4.64 J/cm2) with WC and NaF; G8: laser (4.64 J/cm2) without WC and NaF; G9: laser (8.92 J/cm2) with WC and NaF; G10: laser (8.92 J/cm2) without WC and NaF. The NaF gel was applied alone or after 4 min of irradiation. After 14 days of acid challenge, the samples were sectioned and the Knoop microhardness (KHN) test was done at different depths (30, 60, 90 and 120 μm) from the outer dentin surface. Data were analyzed by one-way ANOVA and Fisher’s test (α=5%). Results: The results showed that G8 and G10 presented higher KHN than the G1 for the depths of 30 and 60 μm, indicating an increase of the acid resistance of the dentin in up to 35% (p<0.05). Conclusions: The use of Er,Cr:YSGG laser irradiation at 4.64 J/ cm2 and 8.92 J/cm2 without water cooling and associated with 2% NaF can increase the acid resistance of human root dentin. .


Subject(s)
Humans , Dentin/drug effects , Dentin/radiation effects , Lasers, Solid-State/therapeutic use , Sodium Fluoride/therapeutic use , Tooth Demineralization/prevention & control , Tooth Root/drug effects , Tooth Root/radiation effects , Analysis of Variance , Cold Temperature , Dental Caries/prevention & control , Dental Enamel/drug effects , Dental Enamel/radiation effects , Dose-Response Relationship, Radiation , Hardness Tests , Reference Values , Reproducibility of Results , Statistics, Nonparametric , Surface Properties , Time Factors , Water/chemistry
20.
Article in English | IMSEAR | ID: sea-154607

ABSTRACT

Objective: This study aimed to compare digital techniques for evaluating dental enamel de-/remineralization. Materials and Methods: Sixty extracted molars were subjected to a process of de- and remineralization. Radiographs were taken before and after each stage. These radiographs were evaluated by the conventional method and were then scanned and analyzed either with or without the use of image enhancement. Moreover, the gray levels (GLs) of the affected areas were measured. Results: All methods exhibited low sensitivity and identical levels of specificity (99.4%). Analysis of the grayscale levels found statistically significant differences between the initial radiographs (P < 0.05). The mean GL of the carious group was significantly lower than that of the remineralized group. The GL did not differ significantly between the initial and final radiographs of the remineralized group, although the mean of the first group was lower than that of the second, which demonstrated that the remineralization process restored the normal density of the dental enamel. Conclusion: Measurement of the mean GL was sufficiently sensitive to detect small alterations in the surface of the enamel.


Subject(s)
Dental Enamel/metabolism , Radiography, Dental/methods , Radiography, Dental, Digital/methods , Tooth Demineralization/prevention & control , Tooth Remineralization/methods
SELECTION OF CITATIONS
SEARCH DETAIL