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1.
Caries Res ; 46(5): 441-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22739669

RESUMO

This study evaluated the effect of Er,Cr:YSGG laser irradiation and professional fluoride application on enamel demineralization and on fluoride formation and retention. In a blind in vitro study, 264 human enamel slabs were distributed into 8 groups: G1--untreated; G2--treated with acidulated phosphate fluoride gel (APF gel, 1.23% F) for 4 min; G3, G4 and G5--irradiated with Er,Cr:YSGG at 2.8, 5.6 and 8.5 J/cm2, respectively; G6, G7 and G8--preirradiated with Er,Cr:YSGG at 2.8, 5.6 and 8.5 J/cm2, respectively, and subjected to APF gel application. Twenty slabs of each group were submitted to a pH-cycling regimen, and enamel demineralization was evaluated in 10 slabs of each group. In the other 10 slabs, CaF2-like material was determined. To evaluate F formed, 10 additional slabs of each group, not subjected to the pH cycling, were submitted to analysis of CaF2-like material and fluorapatite, while the other 3 slabs of each group were evaluated by scanning electron microscopy. The F content was also measured in all pH-cycling solutions. Laser at 8.5 J/cm2 and APF treatment reduced enamel demineralization compared to the control (p < 0.05), but the combination of these treatments was not more efficient than their isolated effect. A higher concentration of retained CaF2-like material was found in laser groups followed by APF in comparison with the APF gel treatment group. The findings suggest that laser treatment at 8.5 J/cm2 was able to decrease hardness loss, even though no additive effect with APF was observed. In addition, laser treatment increased the formation and retention of CaF2 on dental enamel.


Assuntos
Cariostáticos/uso terapêutico , Esmalte Dentário/efeitos da radiação , Fluoretos/uso terapêutico , Lasers de Estado Sólido/uso terapêutico , Desmineralização do Dente/prevenção & controle , Fluoreto de Fosfato Acidulado/análise , Fluoreto de Fosfato Acidulado/uso terapêutico , Apatitas/análise , Apatitas/efeitos da radiação , Fluoreto de Cálcio/análise , Fluoreto de Cálcio/efeitos da radiação , Cariostáticos/análise , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/ultraestrutura , Fluoretos/análise , Dureza , Humanos , Concentração de Íons de Hidrogênio , Eletrodos Seletivos de Íons , Microscopia Eletrônica de Varredura , Método Simples-Cego , Desmineralização do Dente/metabolismo , Remineralização Dentária
2.
Caries Res ; 46(1): 31-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22237162

RESUMO

Although the effect of acidulated phosphate fluoride gel (APF gel) on caries reduction in permanent teeth is based on evidence, the relevance of the clinical application time is still under debate. Also, the effect of 4- versus 1-min application has not been evaluated in deciduous enamel. In a blind, crossover, in situ study of 14 days, 16 adult volunteers wore palatal appliances containing slabs of human permanent and deciduous enamel. At the beginning of each phase, the slabs were submitted to one of the following treatments: no APF application (negative control); APF gel (1.23% F) application for 1 or 4 min. Biofilm accumulation on the slab surface was allowed and the slabs were subjected eight times a day to 20% sucrose, simulating a high cariogenic challenge condition. On the 15th day of each phase, fluoride retained as CaF(2) and fluorapatite (FAp) was determined on the enamel of the slabs and demineralization was assessed by cross-sectional microhardness. Fluoride as CaF(2) and FAp, formed by APF gel application on the enamel slabs not subjected to the cariogenic challenge, was also determined. APF gel reduced demineralization in both enamel types (p < 0.05), but the difference between 1 and 4 min was not statistically significant (p > 0.05). CaF(2) and FAp formed and retained on deciduous and permanent enamel was significantly higher in APF gel groups (p < 0.05), but no significant difference was found between 1 and 4 min (p > 0.05). The findings suggest that 1 min of APF gel application provides a similar effect on inhibition of demineralization as 4 min, for both permanent and deciduous enamel.


Assuntos
Fluoreto de Fosfato Acidulado/uso terapêutico , Cariostáticos/uso terapêutico , Esmalte Dentário/efeitos dos fármacos , Fluoretos Tópicos/uso terapêutico , Desmineralização do Dente/prevenção & controle , Dente Decíduo/efeitos dos fármacos , Fluoreto de Fosfato Acidulado/administração & dosagem , Adolescente , Adulto , Apatitas/análise , Apatitas/farmacocinética , Biofilmes/efeitos dos fármacos , Fluoreto de Cálcio/análise , Fluoreto de Cálcio/farmacocinética , Cariogênicos/farmacologia , Cariostáticos/administração & dosagem , Estudos Cross-Over , Esmalte Dentário/metabolismo , Sacarose Alimentar/farmacologia , Fluoretos Tópicos/administração & dosagem , Géis , Dureza , Humanos , Método Simples-Cego , Fatores de Tempo , Desmineralização do Dente/metabolismo , Dente Decíduo/metabolismo , Adulto Jovem
3.
Caries Res ; 44(1): 55-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20110697

RESUMO

Models to evaluate the anticaries potential of fluoride (F) formulations containing monofluorophosphate (MFP) should consider the release of F ion to the oral environment by its enzymatic hydrolysis. This was tested in situ, using a test plaque of a strain of Streptococcus mutans which presents high MFPase activity at pH 5.0. The test plaque was exposed to non-F or MFP (1,450 microg F/g) dentifrices and the fluid phase of the plaque was analyzed after 15, 30, 45 and 75 min. MFP concentration in the plaque fluid decreased over time after exposure to MFP dentifrice, but F ion reached 134.9 +/- 32.0 microM at 15 min and decreased significantly only at 75 min, suggesting continuous MFP hydrolysis by the test plaque.


Assuntos
Cariostáticos/metabolismo , Placa Dentária/microbiologia , Fluoretos/metabolismo , Fosfatos/metabolismo , Streptococcus mutans/metabolismo , Adolescente , Adulto , Cálcio/análise , Cariostáticos/análise , Compostos Cromogênicos , Estudos Cross-Over , Placa Dentária/química , Dentifrícios/metabolismo , Método Duplo-Cego , Feminino , Fluoretos/análise , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Masculino , Pessoa de Meia-Idade , Fosfatos/análise , Monoéster Fosfórico Hidrolases/metabolismo , Espectrofotometria , Streptococcus mutans/enzimologia , Fatores de Tempo , Adulto Jovem
4.
Caries Res ; 43(4): 278-85, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19439949

RESUMO

Although the anticaries effect of fluoride (F) dentifrices is clearly established, the relative importance of F taken up by dental plaque not removed by brushing and of F products (CaF(2)-like) formed on totally cleaned enamel for the subsequent inhibition of demineralization is not known. Both effects were evaluated using conventional (1,100 microg F/g) and low-F concentration (500 microg F/g) dentifrices in a randomized, crossover, double-blind in situ study. Enamel blocks not treated or pretreated with the dentifrices to form CaF(2)-like deposits were mounted in palatal appliances in contact with a Streptococcus mutans test plaque. Volunteers brushed with non-F (negative control), low-F or conventional dentifrices and inserted the appliance in the mouth. F concentration in the fluid and solid phases of the test plaque was determined after 30 min, and a rinse with 20% sucrose solution was performed. After additional 45 min, plaque was collected and the loss of surface hardness at different test-plaque depths was measured. CaF(2)-like deposition on enamel and F taken up by plaque due to the use of F dentifrices were able to significantly increase F concentration in the fluid phase of the test plaque, but only the latter significantly reduced the loss of hardness because of the 20-30 times higher F concentration. Also, significant differences between the low-F and conventional dentifrices were observed for F on enamel, in plaque and on the subsequent loss of hardness. The results suggest that uptake of F by dental plaque not removed by brushing may be the main cause of the anticaries effect of F dentifrices.


Assuntos
Fluoreto de Cálcio/administração & dosagem , Cariostáticos/administração & dosagem , Esmalte Dentário/efeitos dos fármacos , Dentifrícios/uso terapêutico , Streptococcus mutans/metabolismo , Adulto , Análise de Variância , Fluoreto de Cálcio/análise , Fluoreto de Cálcio/farmacocinética , Cariostáticos/farmacocinética , Estudos Cross-Over , Placa Dentária/química , Placa Dentária/complicações , Placa Dentária/microbiologia , Placa Dentária/prevenção & controle , Dentifrícios/química , Dentifrícios/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dureza/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Streptococcus mutans/efeitos dos fármacos , Desmineralização do Dente/etiologia , Desmineralização do Dente/microbiologia , Desmineralização do Dente/prevenção & controle , Dente Artificial , Adulto Jovem
5.
Caries Res ; 41(5): 406-12, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17713342

RESUMO

The aim of this study was to investigate the temporal relationship between changes in biofilm composition and enamel demineralization following exposure to sucrose. A crossover blind study was conducted in situ in three phases, during which 12 volunteers, divided into three groups, subjected enamel slabs 8 times/day to water (negative control), 10% glucose + 10% fructose (active control) or 20% sucrose solution. Biofilms accumulated for 3, 7 and 14 days were collected and analyzed biochemically and microbiologically, and mineral loss from enamel (deltaZ) was evaluated. Significantly higher deltaZ was found in the sucrose group after 7 days. However, on the 3rd day, lactobacilli, insoluble extracellular polysaccharide (EPS) and intracellular polysaccharide were significantly higher, and the calcium, inorganic phosphorus and fluoride concentrations in the biofilm were significantly lower in the sucrose group than in the negative controls. The only significant difference compared to glucose + fructose treatment was a higher insoluble EPS concentration. The data suggest that, although sucrose induces significant enamel demineralization only after 7 days of biofilm accumulation, changes in the biofilm composition are observed earlier.


Assuntos
Biofilmes , Polissacarídeos Bacterianos/análise , Sacarose/efeitos adversos , Edulcorantes/efeitos adversos , Desmineralização do Dente/induzido quimicamente , Adolescente , Adulto , Análise de Variância , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Estudos Cross-Over , Esmalte Dentário/química , Frutose/efeitos adversos , Glucose/efeitos adversos , Dureza , Humanos , Método Simples-Cego , Fatores de Tempo , Desmineralização do Dente/microbiologia
6.
Oper Dent ; 41(1): E29-38, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26449589

RESUMO

OBJECTIVE: The purpose of this study was to investigate the effects on the enamel properties and effectiveness of bleaching using 35% hydrogen peroxide (HP) when applying toothpastes with different active agents prior to dental bleaching. METHODS: Seventy enamel blocks (4 × 4 × 2 mm) were submitted to in vitro treatment protocols in a tooth-brushing machine (n=10): with distilled water and exposure to placebo gel (negative control [NC]) or HP bleaching (positive control [PC]); and brushing with differing toothpastes prior to HP bleaching, including potassium nitrate toothpaste (PN) containing NaF, conventional sodium monofluorophosphate toothpaste (FT), arginine-based toothpastes (PA and SAN), or a toothpaste containing bioactive glass (NM). Color changes were determined using the CIE L*a*b* system (ΔE, ΔL, Δa, and Δb), and a roughness (Ra) analysis was performed before and after treatments. Surface microhardness (SMH) and cross-sectional microhardness (CSMH) were analyzed after treatment. Data were analyzed with repeated measures ANOVA for Ra, one-way ANOVA (SMH, ΔE, ΔL, Δa, and Δb), split-plot ANOVA (CSMH), and Tukey post hoc test (α<0.05). The relationship between the physical surface properties and color properties was evaluated using a multivariate Canonical correlation analysis. RESULTS: Color changes were statistically similar in the bleached groups. After treatments, SMH and CSMH decreased in PC. SMH increased significantly in the toothpaste groups vs the negative and positive control (NM > PA = SAN > all other groups) or decreased HP effects (CSMH). Ra increased in all bleached groups, with the exception of NM, which did not differ from the NC. The variation in the color variables (ΔL, Δa, and Δb) explained 21% of the variation in the physical surface variables (Ra and SMH). CONCLUSION: The application of toothpaste prior to dental bleaching did not interfere with the effectiveness of treatment. The bioactive glass based toothpaste protected the enamel against the deleterious effects of dental bleaching.


Assuntos
Clareamento Dental , Cremes Dentais , Estudos Transversais , Esmalte Dentário , Peróxido de Hidrogênio
7.
J Dent Res ; 83(1): 71-5, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14691117

RESUMO

Since the effect of the combination of methods of fluoride use on enamel demineralization and on plaque composition is not clearly established, this study examined the effect of the combination of acidulated phosphate fluoride (APF) application and F dentifrice on enamel demineralization and on plaque composition. In this crossover study, 16 volunteers, wearing a palatal appliance containing bovine enamel blocks, were subjected to 4 treatment groups: non-fluoridated dentifrice (PD), FD, APF+PD, and APF+FD. The APF was applied to the enamel before the 14-day experimental period. During the experimental period, test dentifrices were applied 3x/day, and a 20% sucrose solution was applied 4x and 8x/day by being dripped on the blocks. Although APF application was able either to increase F concentration in plaque or to reduce the % of mutans streptococci, its combination with F dentifrice use neither reduced enamel mineral loss nor changed any other measured plaque variable with respect to the FD group alone.


Assuntos
Fluoreto de Fosfato Acidulado/uso terapêutico , Cariogênicos/efeitos adversos , Cariostáticos/uso terapêutico , Esmalte Dentário/efeitos dos fármacos , Placa Dentária/química , Dentifrícios/uso terapêutico , Fluoretos/uso terapêutico , Sacarose/efeitos adversos , Desmineralização do Dente/etiologia , Adulto , Análise de Variância , Animais , Cálcio/análise , Cariostáticos/análise , Bovinos , Estudos Cross-Over , Esmalte Dentário/patologia , Placa Dentária/microbiologia , Fluoretos/análise , Dureza , Humanos , Fósforo/análise , Placebos , Método Simples-Cego , Streptococcus mutans/efeitos dos fármacos
8.
Oper Dent ; 29(5): 509-14, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15470872

RESUMO

Since the importance of luting cement on secondary caries in enamel and dentin is unknown, an in situ crossover study was conducted in three phases over 21 days using a fluoride-containing toothpaste. One hundred and twenty-six metallic restorations were cemented into the dentinoenamel junction of slabs of human teeth with zinc phosphate (ZP), resin-modified glass ionomer (GI) or resinous cement (RC). The slabs were inserted onto flanges of the removable partial acrylic dentures of 14 volunteers and covered with gauze to enhance dental plaque accumulation. The volunteers used fluoride toothpaste (1.100 microg F/g, w/w). After 21 days, the biofilm that formed on the slabs was collected for biochemical and microbiological analyses, and the demineralization in enamel-dentin around the restorations was evaluated. The fluoride concentration of biofilm in the GI group was higher (p<0.05) than the ZP and RC groups. Also, the concentration of Zinc in biofilm formed on the slabs cemented with ZP was higher (p<0.05) than the other groups. However, the effect of the luting material on enamel or dentin demineralization was not statistically significant (p>0.05). The data suggest that when fluoride toothpaste is used, the anticariogenic property of the luting cement may not be relevant to the reduction of secondary caries.


Assuntos
Biofilmes , Ligas Dentárias/química , Cárie Dentária/microbiologia , Cimentos Dentários/química , Restauração Dentária Permanente , Streptococcus mutans/fisiologia , Adulto , Cariostáticos/química , Cariostáticos/uso terapêutico , Contagem de Colônia Microbiana , Estudos Cross-Over , Cárie Dentária/etiologia , Esmalte Dentário/microbiologia , Placa Dentária/microbiologia , Dentina/microbiologia , Fluoretos/química , Fluoretos/uso terapêutico , Cimentos de Ionômeros de Vidro/química , Humanos , Pessoa de Meia-Idade , Cimentos de Resina/química , Aço Inoxidável/química , Streptococcus mutans/crescimento & desenvolvimento , Desmineralização do Dente/etiologia , Desmineralização do Dente/microbiologia , Cremes Dentais/uso terapêutico , Zinco/química , Cimento de Fosfato de Zinco/química
9.
Dentomaxillofac Radiol ; 42(5): 20120313, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23412461

RESUMO

OBJECTIVES: The aim of this study was to assess the performance of photostimulable storage phosphor (PSP) radiographs with or without using the sharpen filter and cone beam CT (CBCT) for detecting enamel subsurface demineralization. METHODS: Enamel subsurface demineralization was induced on one of the approximal surfaces of 120 sound human teeth. Standardized images of all teeth were acquired after the demineralization phase using the Digora(®) Optime (Orion Corp./Soredex, Helsinki, Finland) (PSP) and the i-CAT™ (Imaging Sciences International, Hatfield, PA) (CBCT) systems. Three calibrated observers interpreted the images using a five-point scale (1, demineralization definitely absent; 2, demineralization probably absent; 3, unsure; 4, demineralization probably present; and 5, demineralization definitely present). Diagnoses were validated by cross-sectional microhardness profiling in the test areas of the approximal surfaces. Interobserver agreement was analysed using kappa statistics. Accuracy was estimated by the areas under the receiver operating characteristic curves (Az), which were compared using the Kruskal-Wallis test (α = 5%). RESULTS: Interobserver agreement was higher for CBCT (κ = 0.7-0.8), followed by sharpen-filtered (κ = 0.6-0.7) and original (κ = 0.5-0.6) images. CBCT presented the highest accuracy value (Az = 0.897) compared with the original (Az = 0.792) and sharpen-filtered (Az = 0.712) images. However, no statistical differences were observed between the imaging modalities (p = 0.0794). CONCLUSIONS: It can be concluded that PSP radiographs with or without using the sharpen filter and the CBCT images may be useful adjuncts for detecting subtle approximal enamel demineralization.


Assuntos
Tomografia Computadorizada de Feixe Cônico/instrumentação , Esmalte Dentário/diagnóstico por imagem , Intensificação de Imagem Radiográfica/instrumentação , Radiografia Dentária Digital/instrumentação , Desmineralização do Dente/diagnóstico por imagem , Esmalte Dentário/patologia , Filtração/instrumentação , Testes de Dureza , Humanos , Curva ROC , Estatísticas não Paramétricas
10.
J Dent Res ; 90(1): 77-81, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20929723

RESUMO

Because dentin is more caries-susceptible than enamel, its demineralization may be more influenced by additional fluoride (F). We hypothesized that a combination of professional F, applied as acidulated phosphate F (APF), and use of 1100-ppm-F dentifrice would provide additional protection for dentin compared with 1100-ppm-F alone. Twelve adult volunteers wore palatal appliances containing root dentin slabs, which were subjected, during 4 experimental phases of 7 days each, to biofilm accumulation and sucrose exposure 8x/day. The volunteers were randomly assigned to the following treatments: placebo dentifrice (PD), 1100-ppm-F dentifrice (FD), APF + PD, and APF+FD. APF gel (1.23% F) was applied to the slabs once at the beginning of the experimental phase, and the dentifrices were used 3x/day. APF and FD increased F concentration in biofilm fluid and reduced root dentin demineralization, presenting an additive effect. Analysis of the data suggests that the combination of APF gel application and daily regular use of 1100-ppm-F dentifrice may provide additional protection against root caries compared with the dentifrice alone.


Assuntos
Fluoreto de Fosfato Acidulado/uso terapêutico , Biofilmes/efeitos dos fármacos , Cariostáticos/uso terapêutico , Dentifrícios/uso terapêutico , Dentina/efeitos dos fármacos , Fluoretos/uso terapêutico , Desmineralização do Dente/prevenção & controle , Raiz Dentária/efeitos dos fármacos , Fluoreto de Fosfato Acidulado/administração & dosagem , Adulto , Apatitas/análise , Fluoreto de Cálcio/análise , Cariogênicos/efeitos adversos , Cariostáticos/administração & dosagem , Estudos Cross-Over , Placa Dentária/microbiologia , Dentifrícios/administração & dosagem , Dentina/microbiologia , Método Duplo-Cego , Combinação de Medicamentos , Fluoretos/administração & dosagem , Géis , Dureza , Humanos , Microrradiografia , Placebos , Sacarose/efeitos adversos , Fatores de Tempo , Raiz Dentária/microbiologia , Adulto Jovem
11.
J Dent Res ; 87(11): 1032-6, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18946010

RESUMO

The anticaries effect of professional fluoride (F) application has been attributed to calcium-fluoride-like deposits (CaF(2)) formed on enamel, but this has not been clearly demonstrated. We hypothesized that CaF(2) formed on plaque-free enamel by F application would reduce enamel demineralization due to the increase of F availability in fluid of subsequently formed plaque. We created distinct levels of CaF(2) on enamel to evaluate a dose-response effect. Enamel blocks were mounted in contact with a S. mutans test plaque and used in situ by 10 volunteers. F released to the fluid phase of this substrate ("plaque fluid") was measured before a cariogenic challenge. "Plaque fluid" F concentration was highly correlated to the enamel CaF(2) concentration (r = 0.96, p < 0.001) and to consequent enamel demineralization (r = -0.75, p < 0.001). The results suggest that F released to plaque fluid from CaF(2) formed on enamel may play a significant role in the anticaries effect of professionally applied F agents.


Assuntos
Fluoreto de Fosfato Acidulado/farmacocinética , Fluoreto de Cálcio/farmacocinética , Cariostáticos/farmacocinética , Esmalte Dentário/metabolismo , Fluoretos Tópicos/farmacologia , Desmineralização do Dente/prevenção & controle , Fluoreto de Fosfato Acidulado/administração & dosagem , Animais , Apatitas/metabolismo , Disponibilidade Biológica , Fluoreto de Cálcio/administração & dosagem , Cariostáticos/administração & dosagem , Bovinos , Estudos Cross-Over , Placa Dentária/metabolismo , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dureza , Humanos
12.
Caries Res ; 41(1): 9-15, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17167254

RESUMO

It has been suggested that enamel would resist higher frequencies of sucrose exposure if fluoride from water or dentifrice is being used. However, the effect of increasing frequencies of sugar on dental biofilm composition is not well known. Ten volunteers living in a fluoridated area wore palatal appliances bearing human enamel slabs during 14 days. The slabs were exposed to 20% sucrose solution 0 (control), 2, 4, 6, 8 or 10 times/day and the volunteers used fluoride dentifrice 3 times/day. Enamel demineralization was significantly greater than control for sucrose frequencies higher than 6 times/day. However, biofilm mass, total microbiota, total streptococci, lactobacilli counts and insoluble extracellular polysaccharide concentration increased, while Ca, P(i) and F concentration in whole biofilm decreased significantly, with frequencies of sucrose exposure lower than 6 times/day. The findings confirm that fluoride can reduce enamel demineralization if sucrose consumption is not higher than 6 times/day, but changes in the biochemical and microbiological composition of the biofilm are observed with lower frequencies of sucrose use.


Assuntos
Biofilmes/efeitos dos fármacos , Cariostáticos/farmacologia , Fluoretos/farmacologia , Sacarose/administração & dosagem , Desmineralização do Dente/tratamento farmacológico , Adolescente , Adulto , Análise de Variância , Criança , Contagem de Colônia Microbiana , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Dureza/efeitos dos fármacos , Humanos , Método Simples-Cego , Sacarose/efeitos adversos , Desmineralização do Dente/induzido quimicamente
13.
Caries Res ; 40(1): 28-32, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16352877

RESUMO

The relationship between sucrose concentration and cariogenic potential was studied in situ. Adult volunteers wore intraoral palatal appliances containing human dental enamel blocks, which were extraorally submitted 8 times a day for 14 days, to the treatments: deionized distilled water and sucrose solutions from 1 to 40%. The biofilm formed was analyzed with respect to acidogenicity and biochemical composition; enamel demineralization was evaluated by microhardness. The results showed that 1% sucrose is less cariogenic than 5% or higher concentrations, although sucrose solution at 40% was still able to increase the concentration of insoluble polysaccharide in the biofilm formed. The findings suggest that the threshold of sucrose solution concentration for the formation of a cariogenic biofilm is 5%, which provided the same cariogenic potential as that observed for 10 and 20% sucrose solution.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cariogênicos/administração & dosagem , Placa Dentária/química , Sacarose/administração & dosagem , Desmineralização do Dente/induzido quimicamente , Adulto , Análise de Variância , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Relação Dose-Resposta a Droga , Dureza/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Método Simples-Cego
14.
Dentomaxillofac Radiol ; 34(3): 133-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15897282

RESUMO

OBJECTIVE: To compare the diagnostic performance of linear and logarithmically contrast-enhanced subtraction images, acquired with digital and digitized radiographs, in detecting approximal enamel subsurface demineralization. METHODS: Fifty caries-free human third molars were immersed in a demineralizing solution for 60, 75, 90, and 120 days, in order to induce artificial enamel subsurface demineralization. The teeth were coated with nail varnish, leaving only a circular window of approximately 7 mm2 in one of the approximal surfaces, allowing contact with the solution. Standardized radiographs of the teeth were taken prior to and after the demineralization period with three digital systems, CygnusRay MPS, DenOptix and DIGORA, and InSight film. Conventional, digital and digitized radiographs were assessed by three experienced radiologists. Linear and logarithmically contrast-enhanced subtraction images were acquired and then examined by a fourth independent radiologist. For the validation of the radiographic diagnosis, the enamel test areas were submitted to Knoop microhardness profiling. Radiographic interpretation data was evaluated using ROC analysis. The areas under the ROC curves (Az) were compared by the chi-squared test. The level of significance was set at P=0.05. RESULTS: No significant differences were found between linear and logarithmically contrast- enhanced subtraction images, acquired with the four studied modalities: CygnusRay MPSlinear (Az=0.95), CygnusRay MPSlog (Az=0.98), DenOptixlinear (Az=0.97), DenOptixlog (Az=0.99), DIGORAlinear (Az=0.98), DIGORAlog (Az=0.98), digitized radiographylinear (Az=0.99), digitized radiographylog (Az=0.99). CONCLUSION: Linear and logarithmically contrast-enhanced subtraction images, acquired with digital and digitized radiographs, were diagnostically comparable for assessing enamel subsurface demineralization.


Assuntos
Esmalte Dentário/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Técnica de Subtração/estatística & dados numéricos , Desmineralização do Dente/diagnóstico por imagem , Distribuição de Qui-Quadrado , Meios de Contraste , Dureza , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Modelos Lineares , Dente Serotino , Curva ROC , Radiografia Dentária Digital/estatística & dados numéricos , Reprodutibilidade dos Testes , Fatores de Tempo
15.
Caries Res ; 39(3): 255-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15914990

RESUMO

This crossover study evaluated the effect of calcium carbonate (CaCO(3))-based monofluorophosphate dentifrice on enamel remineralization. Ten volunteers wore palatal appliances containing four enamel blocks with caries-like lesions, two of them covered by a test plaque of mutans streptococci. The following treatments were evaluated: a negative control, a silica-based or a CaCO(3)-based dentifrice, and the percentage of enamel surface microhardness recovery was determined. The CaCO(3)-based dentifrice was more effective than the negative control on the enhancement of enamel remineralization, either in the presence or absence of test plaque. This efficacy was also shown by the silica-based dentifrice but only in the presence of test plaque.


Assuntos
Carbonato de Cálcio/uso terapêutico , Cariostáticos/uso terapêutico , Esmalte Dentário/efeitos dos fármacos , Dentifrícios/uso terapêutico , Remineralização Dentária , Análise de Variância , Animais , Materiais Biomédicos e Odontológicos/uso terapêutico , Bovinos , Estudos Cross-Over , Cárie Dentária/tratamento farmacológico , Cárie Dentária/microbiologia , Esmalte Dentário/química , Dentifrícios/química , Fluoretos/uso terapêutico , Dureza/efeitos dos fármacos , Humanos , Compostos Orgânicos , Fosfatos/uso terapêutico
16.
Caries Res ; 39(2): 123-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15741724

RESUMO

Since the effect of iron (Fe) on the cariogenicity of sucrose in humans is unexplored, this study assessed in situ the effect of Fe co-crystallized with sucrose (Fe-sucrose) topically applied in vitro on the acidogenicity, biochemical and microbiological composition of the dental biofilm formed in vivo and on the demineralization of the enamel. During two phases of 14 days each, 16 volunteers wore palatal appliances containing blocks of human enamel, which were submitted to four groups of separate treatments: (1) water; (2) 20% sucrose; (3) 20% (w/v) sucrose plus 18 microg Fe/ml, and (4) 20% (w/v) sucrose plus 70 microg Fe/ml. The solutions were dripped onto the blocks 8 times per day. The biofilms formed on the blocks were analyzed with respect to acidogenicity, biochemical and microbiological composition. Mineral loss was determined on enamel by surface and cross-sectional microhardness. Lower demineralization was found in the blocks subjected to Fe-sucrose (70 microg Fe/ml) than in those treated with sucrose (p < 0.05). This concentration of Fe also reduced significantly the populations of mutans streptococci in the biofilm formed on the blocks. In conclusion, our data suggest that Fe may reduce in situ the cariogenic potential of sucrose and the effect seems to be related to the reduction in the populations of mutans streptococci in the dental biofilm formed.


Assuntos
Biofilmes/efeitos dos fármacos , Cariostáticos/uso terapêutico , Esmalte Dentário/microbiologia , Compostos Férricos/uso terapêutico , Desmineralização do Dente/prevenção & controle , Ácidos , Adulto , Biofilmes/crescimento & desenvolvimento , Cariogênicos/efeitos adversos , Contagem de Colônia Microbiana , Óxido de Ferro Sacarado , Ácido Glucárico , Dureza , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/fisiologia , Minerais/análise , Método Simples-Cego , Streptococcus/crescimento & desenvolvimento , Streptococcus/fisiologia , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/fisiologia , Sacarose/efeitos adversos
17.
J Clin Periodontol ; 29(12): 1059-64, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12492904

RESUMO

BACKGROUND: The objective of this study was to evaluate the effect of three commercial anti-plaque dentifrices containing 0.3% triclosan + 2% pvm/ma (Colgate Total), 0.3% triclosan + 0.75% Zn (Signal Global) and 0.3% triclosan + 5% PPi (Crest Complete) in comparison with an experimental dentifrice (0.3% triclosan + 2% pvm/ma + 0.75% Zn + 4% PPi) and a control dentifrice without anti-plaque agents on trypsin-like activity in dental plaque (detected by the hydrolysis of [Na-Benzoyl-DL-Anginine p-Nitroanilide (BAPNA)] and volatile sulphur compounds (VSCs) in mouth air during experimental gingivitis development. METHOD: A 5-step double blind, crossover experimental gingivitis study was conducted on 19 volunteers during a 21-day period. The volunteers refrained from brushing an experimental quadrant of teeth. The dentifrices were applied to those teeth via toothshield three times per day; simultaneously they brushed the other teeth with the same dentifrice. After each period, VSCs in mouth air and BAPNA hydrolysis by dental plaque accumulated in the experimental quadrant were determined. RESULTS: There was an increase (p < 0.05) in VSCs in mouth air when experimental gingivitis was induced in only one quadrant of teeth. None of the dentifrices was able to avoid the increase of VSCs during the experimental gingivitis development. The majority of the antiplaque dentifrices evaluated reduced the increase of VSC formation in comparison with the control (p < 0.05). There was no relationship between the ability of the dentifrices in reducing VSC formation and the inhibition of trypsin-like activity in dental plaque. CONCLUSIONS: Anti-plaque dentifrices reduce the increase of VSCs that occurs during the development of experimental gingivitis.


Assuntos
Anti-Infecciosos/uso terapêutico , Placa Dentária/tratamento farmacológico , Dentifrícios/uso terapêutico , Gengivite/metabolismo , Halitose/prevenção & controle , Compostos de Enxofre/metabolismo , Triclosan/uso terapêutico , Adulto , Análise de Variância , Anti-Infecciosos/administração & dosagem , Benzoilarginina Nitroanilida , Testes Respiratórios , Estudos Cross-Over , Placa Dentária/enzimologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Estatísticas não Paramétricas , Triclosan/administração & dosagem , Tripsina/metabolismo
18.
Caries Res ; 36(3): 167-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12065968

RESUMO

Since lactose has been used as an excipient in powdered sweeteners, we evaluated its effect on dentine demineralization, in an in situ crossover study. Twelve adult volunteers wore palatal appliances containing 4 blocks of bovine root dentine, which were submitted 4 times a day to: distilled water (negative control), aqueous solution of powdered sweetener (Zero Cal); experimental group), 1.5% lactose solution (active group), 1.5% sucrose solution (positive control). After 15 days, microhardness was determined on dentine surface (SMH) and on the sectioned blocks (CSMH). All groups presented statistical differences in SMH before and after the treatments; water increased, while sweetener, lactose and sucrose decreased SMH. By CSMH, the only significant difference was observed after sucrose treatment. The data suggest that sweeteners containing lactose as a bulking agent may be cariogenic for root dentine.


Assuntos
Dentina/efeitos dos fármacos , Lactose/farmacologia , Edulcorantes/farmacologia , Desmineralização do Dente/etiologia , Raiz Dentária/efeitos dos fármacos , Adulto , Análise de Variância , Animais , Aspartame/farmacologia , Cariogênicos/efeitos adversos , Bovinos , Estudos Cross-Over , Excipientes , Dureza , Humanos , Lactose/efeitos adversos , Método Simples-Cego , Estatística como Assunto , Sacarose/efeitos adversos , Desmineralização do Dente/fisiopatologia , Água
19.
Caries Res ; 37(3): 194-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12740543

RESUMO

Since the effect of calcium carbonate (CaCO(3)) based dentifrice on enamel demineralization is not clearly established, it was evaluated using the IEDT model described by Zero's group in 1992. This study had a crossover design and 10 volunteers were submitted to 3 treatment groups: a negative control, brushing without dentifrice; an active control, brushing with silica-based dentifrice (SiO(2)/MFP group), and the experimental group, brushing with CaCO(3)-based dentifrice (CaCO(3)/MFP). Both dentifrices contained 1,500 microgram F/g (w/w) as sodium monofluorophosphate (MFP). Enamel surface microhardness was determined in the dental blocks and the percentage change in relation to baseline was calculated. Fluoride uptake in enamel and its concentration in 'test plaque' were determined. The results showed that the dentifrice containing CaCO(3)/MFP was more effective than SiO(2)/MFP in reducing enamel demineralization (p < 0.05). A higher concentration of fluoride ion was found in 'test plaque' treated with CaCO(3)/MFP than in the negative control (p < 0.05). The results suggest that CaCO(3) abrasive may enhance the effect of fluoride present in dentifrice on dental caries control.


Assuntos
Carbonato de Cálcio/farmacologia , Cariostáticos/uso terapêutico , Fluoretos/uso terapêutico , Fosfatos/uso terapêutico , Desmineralização do Dente/prevenção & controle , Adulto , Animais , Cariostáticos/farmacocinética , Bovinos , Estudos Cross-Over , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/metabolismo , Placa Dentária/metabolismo , Dentifrícios/química , Combinação de Medicamentos , Sinergismo Farmacológico , Fluoretos/farmacocinética , Dureza/efeitos dos fármacos , Humanos , Fosfatos/farmacocinética , Dióxido de Silício/farmacologia
20.
Bol. Asoc. Argent. Odontol. Niños ; 35(1): 4-10, mar. 2006. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-427667

RESUMO

Se considera que una exposición diaria a fluoruros es importante en términos de beneficios (reducción de caries) como de riesgos (fluorosis dental). El objetivo de este trabajo fue analizar la concentración de fluoruro en aguas minerales y mineralizadas disponibles en comercios de la ciudad de Buenos Aires. Fueron adquiridas 18 marcas comerciales, 12 minerales y 6 mineralizadas. Cuadro de las marcas fueron encontradas en tres diferentes supermercados, seis en dos y ocho en uno. Los análisis fueron realizados con el electrodo específico Orion 96-09 conectado a un analizador de iones Orion, SA 720, que fueron calibrados con soluciones patrones de fluoruro (0,10 a 1,0 ug/mL) tamponadas con TISAB II (1:1, v/v). Una cantidad de 0,5 ml de cada muestra se utilizó para los análisis. Estos análisis, realizados en la FOUBA, fueron validados por el laboratorio de Bioquímica Oral de FOB-UNICAMP y las diferencias entre los resultados no fueron estadísticamente significativos (p=0,98). En las muestras de aguas minerales analizadas fueron encontradas concentraciones de fluoruro que variaron entre 0,19 a 1,87 ppm (ug/mL). En las aguas mineralizadas, las concentraciones variaron de 0,51 a 1,36 ppm. En ninguna de las muestras fue encontrada una concentración de fluoruro mayor a 2,0 ug/L, máximo permitido por las reglamentaciones argentinas, aunque no se adaptan a las normas locales de etiquetado de productos a la venta. Siete muestras de agua, 4 minerales (Eco de los Andes, Sierra de los Padres, Villavicencio y Villa del Sur) y 3 mineralizadas (Cimes, Glaciar y Spring Time), presentaron una concentración de fluoruro mayor a 1,0 aunque no figura en la etiqueta "contiene fluoruro" de acuerdo con la norma CODEX STAN 108-1981 (Rev. 1, 1997). Conclusión: todas las muestras de aguas contienen fluoruros en su composición y la ingesta diaria por parte de los niños de aquellas con mayor concentración de fluoruros, puede ser un factor de riesgo potencial de fluorosis dental


Assuntos
Humanos , Criança , Cárie Dentária , Estudo de Avaliação , Fluorose Dentária , Eletrodos Seletivos de Íons , Águas Minerais , Fatores de Risco , Interpretação Estatística de Dados , Argentina , Brasil
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