RESUMEN
This study evaluated the effect of titanium tetrafluoride (TiF4) varnish on the development of dentin carious lesions. Bovine root dentin samples were treated for 6 h with: (A) 4% TiF4 varnish (2.45% F); (B) 5.42% sodium fluoride (NaF) varnish (2.45% F); (C) 2% chlorhexidine (CHX) gel - positive control; (D) placebo varnish; or (E) untreated - negative control (n = 4 × biological triplicate, n = 12). Treated dentin samples were exposed to human saliva mixed with McBain saliva (1:50) for the first 8 h in 24-well plates. Thereafter, the medium was removed, and McBain saliva containing 0.2% sucrose was applied for 16 h. From days 2 to 5, McBain saliva with sucrose was replaced daily (37°C, 5% CO2). The demineralization was measured using transverse microradiography, while the effect on biofilm was analyzed using viability, extracellular polysaccharide (EPS), and lactic acid production assays. The data were statistically analyzed (p < 0.05). All treatments (fluorides and CHX) significantly reduced the biofilm viability compared to placebo varnish and negative control. However, none of them was able to reduce the colony-forming unit counting for total microorganism, total streptococci, and Streptococcus mutans. NaF significantly reduced the number of Lactobacillus sp. compared to negative control. No effect was seen on lactic acid production neither on EPS synthesis, except that CHX significantly reduced the amount of insoluble EPS. Both fluorides were able to reduce dentin demineralization compared to placebo varnish and negative control; TiF4 had a better effect in reducing mineral loss and lesion depth than NaF. Therefore, TiF4 varnish has the best protective effect on dentin carious lesion formation using this model.
Asunto(s)
Biopelículas/efectos de los fármacos , Dentina/efectos de los fármacos , Fluoruros/uso terapéutico , Titanio/uso terapéutico , Desmineralización Dental/prevención & control , Animales , Cariostáticos , Bovinos , Dentina/patología , Fluoruros Tópicos , Humanos , Técnicas In Vitro , Ácido Láctico , Lactobacillus/efectos de los fármacos , Fluoruro de Sodio/uso terapéutico , Streptococcus mutans/efectos de los fármacosRESUMEN
OBJECTIVE: Microcosm biofilm has been applied to induce carious lesions in dentin. However, no study has been done to compare the impact of the type of model for providing nutrients to microcosm biofilm formation on dentin. This study compared the performance of two kinds of models (static and semi-dynamic) on the biofilm formation and the development of dentin carious lesions. MATERIAL AND METHODS: In both models, biofilm was produced using inoculum from pooled human saliva mixed with McBain saliva for the first 8 h (5% CO2 and 37°C). Afterwards, for the static model, the samples were placed in 24-wells microplate containing McBain saliva with 0.2% sucrose, which was replaced at 24 h. In the semi-dynamic model, the samples were submitted to artificial mouth system with continuous flow of McBain saliva with 0.2% sucrose (0.15 ml/min, 37°C) for 10 h a day (for the other 14 h, no flow was applied, similarly to the static model). After 5 days, biofilm viability was measured by fluorescence and dentin demineralization by transverse microradiography. RESULTS: Biofilm viability was significantly lower for the static compared with semi-dynamic model, while dentin demineralization was significantly higher for the first one (p<0.05). The static model was able to produce a higher number of typical subsurface lesions compared with the semi-dynamic model (p<0.05). CONCLUSIONS: The type of model (static and semi-dynamic) applied in the microcosm biofilm may have influence on it's viability and the severity/profile of dentin carious lesions.
Asunto(s)
Biopelículas/crecimiento & desarrollo , Caries Dental/microbiología , Dentina/microbiología , Modelos Biológicos , Animales , Bovinos , Humanos , Viabilidad Microbiana , Microrradiografía , Saliva/microbiología , Propiedades de Superficie , Factores de Tiempo , Desmineralización Dental/microbiologíaRESUMEN
Titanium tetrafluoride (TiF4) is known for interacting with enamel reducing demineralization. However, no information is available about its potential antimicrobial effect. OBJECTIVES: This study evaluated the antimicrobial and anti-caries potential of TiF4 varnish compared to NaF varnish, chlorhexidine gel (positive control), placebo varnish and untreated (negative controls) using a dental microcosm biofilm model. MATERIAL AND METHODS: A microcosm biofilm was produced on bovine enamel previously treated with the varnishes, using inoculum from human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. All experiments were performed in biological triplicate (n=4/group in each experiment). Factors evaluated were: bacterial viability (% dead and live bacteria); CFU counting (log10 CFU/mL); and enamel demineralization (transverse microradiography - TMR). Data were analysed using ANOVA/Tukey's test or Kruskal-Wallis/Dunn's test (p<0.05). RESULTS: Only chlorhexidine significantly increased the number of dead bacteria (68.8±13.1% dead bacteria) compared to untreated control (48.9±16.1% dead bacteria). No treatment reduced the CFU counting (total microorganism and total streptococci) compared to the negative controls. Only TiF4 was able to reduce enamel demineralization (ΔZ 1110.7±803.2 vol% µm) compared to both negative controls (untreated: ΔZ 4455.3±1176.4 vol% µm). CONCLUSIONS: TiF4 varnish has no relevant antimicrobial effect. Nevertheless, TiF4 varnish was effective in reducing enamel demineralization under this model.
Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Cariostáticos/farmacología , Esmalte Dental/microbiología , Fluoruros/farmacología , Streptococcus/efectos de los fármacos , Titanio/farmacología , Análisis de Varianza , Animales , Bovinos , Clorhexidina/farmacología , Recuento de Colonia Microbiana , Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Humanos , Viabilidad Microbiana/efectos de los fármacos , Microrradiografía , Efecto Placebo , Distribución Aleatoria , Reproducibilidad de los Resultados , Saliva/microbiología , Fluoruro de Sodio/farmacología , Estadísticas no Paramétricas , Streptococcus/crecimiento & desarrolloRESUMEN
Current knowledge supports the application of TiF4 varnish to protect against tooth caries and erosion; however, it is indispensable to know its cytotoxic potential and the mechanism involved on it before applying in patients. Therefore, this study aimed to evaluate 1) The cytotoxic effect of titanium tetrafluoride (TiF4) varnish compared with sodium fluoride (NaF) varnish on murine fibroblast (NIH/3T3), varying the fluoride concentration and time of treatment and 2) The percentage of apoptosis and its mechanism (both mitochondrial mediated by the Bcl-2 family- and death receptorpathways) in human gingival fibroblasts (HGF) and murine fibroblasts (NIH/3T3) treated with TiF4 varnish compared to NaF varnish for 6 h. Step 1) NIH/3T3 were exposed to NaF or TiF4 varnishes containing 0.95, 1.95 or 2.45% F, for 6, 12 or 24 h. MTT viability (n=6) and Hoescht/PI stain assays (n=3) as well as the cells morphology (HE, only for 24 h, n=3) and stiffness (AFM, only for 2.45% F, 6 or 12 h) were analyzed. Both varnishes, at 1.90 and 2.45% F, reduced cells viability by similar extent (33-86% at 6 h, 35-93% at 12 h, and 87-98% at 24 h) compared to control, regardless of the type of fluoride. TiF4 and NaF (2.45% F) reduced cell stiffness to a similar extent, but only TiF4 differed from control. Step 2) HGF and NIH/3T3 were exposed to NaF or TiF4 (2.45% F) varnishes for 6 h. Cells were examined by the TUNEL method using fluorescence microscope. The caspases-3, -8 and -9 activities were assessed. The cDNA for cytocrome c, Bax, Bad, Bcl-2, VDAC-1 and Fas-L was amplified by quantitative PCR (qPCR). Bax, Bcl-2 and Fas-L were further detected by western blot. Both fluorides similarly increased the percentage of apoptosis, while they failed in activating caspases-3, -8 and -9 for both types of cells. Bax/Bcl-2 ratio, cytochrome C and VDAC-1 gene expressions were not altered by both fluoride treatments. However, NaF varnish increased the amplification of Fas-L gene for NIH/3T3 and HGF, while TiF4 varnish induced lower Bad/Bcl-2 ratio expression compared to control for NIH/3T3, but not for HGF. No effect of the fluorides was detected in the proteins analysis. TiF4 and NaF have similar cytotoxicity on NIH/3T3, which is dependent on the F concentration and the exposure time. Both fluorides, at the studied conditions, similarly induce a low percentage of apoptosis, with consequent modest activation of Bcl-2 and Fas-L-dependent signaling pathways.(AU)
Conhecimento atual suporta a aplicação de verniz de TiF4 para proteção contra cárie e erosão dentárias; entretanto, é indispensável conhecer o seu potencial citotóxico e o mecanismo envolvido antes de aplicá-lo em pacientes. Portanto, o objetivo deste estudo foi avaliar 1) o efeito citotóxico do verniz de tetrafluoreto de Titânio (TiF4) comparado ao fluoreto de sódio (NaF), em fibroblastos NIH/3T3, variando a concentração de fluoreto e o tempo de tratamento 2) a porcentagem de apoptose e seus mecanismos (ambos mitocondrial mediado pela família Bcl-2 e pelo receptor de morte celular) em fibroblastos gengivais humanos (FGH) e fibroblastos murinos (NIH/3T3) tratados com verniz de TiF4 comparado com verniz de NaF por 6 h. Etapa 1) NIH/3T3 foram expostos a vernizes de NaF e TiF4 contendo 0,95, 1,95 ou 2,45% F, por 6, 12 ou 24 h. Ensaios de viabilidade por MTT (n=6) e Hoechst 33342/iodeto de propídeo (n=3) bem como a morfologia (HE, apenas para 24 h, n = 3) e a rigidez celular (MFA, apenas para 2,45% F, 6 ou 12 h) foram realizados. Ambos os vernizes com 1,90 e 2,45% F reduziram a viabilidade das células de forma semelhante (33-86% em 6 h, 35-93% em 12 h e 87-98% em 24 h) em comparação com o controle, independentemente do tipo de fluoreto. TiF4 e NaF (2,45%) reduziram de forma similar a rigidez celular, mas somente TiF4 diferiu do controle no período de 6 h. Etapa 2) FGH e NIH/3T3 foram tratadas com verniz de NaF ou TiF4 por 6h. As células foram examinadas pelo método de TUNEL, usando microscopia de fluorescência. A atividade das caspases -3, -8 e -9 foram avaliadas. O cDNA para citocromo C, Bax, Bad, Bcl-2, VDAC-1 e Fas-L foi amplificado e quantificado por PCR em tempo real (qPCR). A expressão das proteínas Bax, Bcl-2 e Fas-L foi quantificada por western blot. Ambos os fluoretos aumentaram de forma semelhante a porcentagem de apoptose, enquanto falharam na ativação de caspases-3, -8 e -9 para ambos tipos celulares. A expressão gênica da relação Bax/Bcl-2, do citocromo C e do VDAC-1 não foram alteradas por ambos fluoretos. No entanto, o verniz NaF aumentou a amplificação do gene Fas-L para ambas as células, enquanto que o verniz TiF4 induziu menor expressão da razão Bad/Bcl-2 em comparação com o controle para NIH/3T3, mas não para FGH. Nenhum efeito foi detectado na análise de proteínas. TiF4 e NaF apresentam citotoxicidade similar em NIH/3T3, a qual é dependente da concentração de F e do tempo de exposição. Ambos os fluoretos, nas condições estudadas, induzem uma baixa porcentagem de apoptose, com consequente modesta ativação das vias de sinalização dependentes de Bcl-2 e Fas-L.(AU)
Asunto(s)
Humanos , Animales , Ratones , Cariostáticos/farmacología , Fibroblastos/efectos de los fármacos , Fluoruros Tópicos/farmacología , Titanio/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Supervivencia Celular/efectos de los fármacos , Encía/citología , Etiquetado Corte-Fin in Situ , Microscopía Fluorescente , Células 3T3 NIH , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Factores de TiempoRESUMEN
Abstract Titanium tetrafluoride (TiF4) is known for interacting with enamel reducing demineralization. However, no information is available about its potential antimicrobial effect. Objectives This study evaluated the antimicrobial and anti-caries potential of TiF4 varnish compared to NaF varnish, chlorhexidine gel (positive control), placebo varnish and untreated (negative controls) using a dental microcosm biofilm model. Material and Methods A microcosm biofilm was produced on bovine enamel previously treated with the varnishes, using inoculum from human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. All experiments were performed in biological triplicate (n=4/group in each experiment). Factors evaluated were: bacterial viability (% dead and live bacteria); CFU counting (log10 CFU/mL); and enamel demineralization (transverse microradiography - TMR). Data were analysed using ANOVA/Tukey's test or Kruskal-Wallis/Dunn's test (p<0.05). Results Only chlorhexidine significantly increased the number of dead bacteria (68.8±13.1% dead bacteria) compared to untreated control (48.9±16.1% dead bacteria). No treatment reduced the CFU counting (total microorganism and total streptococci) compared to the negative controls. Only TiF4 was able to reduce enamel demineralization (ΔZ 1110.7±803.2 vol% μm) compared to both negative controls (untreated: ΔZ 4455.3±1176.4 vol% μm). Conclusions TiF4 varnish has no relevant antimicrobial effect. Nevertheless, TiF4 varnish was effective in reducing enamel demineralization under this model.
Asunto(s)
Humanos , Animales , Bovinos , Streptococcus/efectos de los fármacos , Titanio/farmacología , Cariostáticos/farmacología , Biopelículas/efectos de los fármacos , Esmalte Dental/microbiología , Fluoruros/farmacología , Antibacterianos/farmacología , Saliva/microbiología , Fluoruro de Sodio/farmacología , Streptococcus/crecimiento & desarrollo , Microrradiografía , Recuento de Colonia Microbiana , Distribución Aleatoria , Efecto Placebo , Clorhexidina/farmacología , Reproducibilidad de los Resultados , Análisis de Varianza , Estadísticas no Paramétricas , Caries Dental/microbiología , Caries Dental/prevención & control , Esmalte Dental/efectos de los fármacos , Viabilidad Microbiana/efectos de los fármacosRESUMEN
OBJECTIVE: Titanium tetrafluoride (TiF4) has shown promising effect in preventing tooth lesions. Therefore, we compared the cytotoxicity of TiF4 with sodium fluoride (NaF) (already applied in Dentistry) considering different fluoride concentrations, pH values and experimental models. MATERIALS AND METHODS: Step 1) NIH/3T3 fibroblasts were exposed to mediums containing NaF or TiF4 (from 0.15 to 2.45% F), both at native and adjusted pH, for 6 h. Step 2) NIH/3T3 were exposed to NaF or TiF4 varnishes with 0.95, 1.95 or 2.45% F (native pH), for 6, 12 or 24 h. We applied MTT (1st and 2nd steps) and Hoescht/PI stain (2nd step) assays. Step 3) NIH/3T3 were exposed to NaF or TiF4 varnish (2.45% F), at native pH, for 6 or 12 h. The cell stiffness was measured by atomic force microscopy (AFM). RESULTS: Step 1) All cells exposed to NaF or TiF4 mediums died, regardless of the F concentration and pH. Step 2) Both varnishes, at 1.90 and 2.45% F, reduced cell viability by similar extents (33-86% at 6 h, 35-93% at 12 h, and 87-98% at 24 h) compared with control, regardless of the type of fluoride. Varnishes with 0.95% F did not differ from control. Step 3) TiF4 and NaF reduced cell stiffness to a similar extent, but only TiF4 differed from control at 6 h. CONCLUSIONS: Based on the results of the 3 experimental steps, we conclude that TiF4 and NaF have similar cytotoxicity. The cytotoxicity was dependent on F concentration and exposure time. This result gives support for testing the effect of TiF4 varnish in vivo.
Asunto(s)
Fenómenos Fisiológicos Celulares/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fluoruros/farmacología , Fluoruro de Sodio/farmacología , Titanio/farmacología , Animales , Cariostáticos/farmacología , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Fibroblastos/citología , Concentración de Iones de Hidrógeno , Ratones , Microscopía de Fuerza Atómica , Modelos Teóricos , Células 3T3 NIH , Factores de TiempoRESUMEN
BACKGROUND: Artificial lesions produced by different protocols might directly influence the response to different remineralising treatments. This study compared the response of different artificial caries-like enamel lesions to home-care and professional fluoride based-remineralising treatments in situ. METHODS: The tested demineralising protocols were methylcellulose- MC gel, polyacrylic acid - PA gel, tetraethyl methylene diphosphanate - TEMDP solution, and acetate- Buffer solution. The lesions were remineralised using an in situ model, following a crossover and double blind design. Twelve subjects wore intra-oral appliances during 3 phases (3 d each): control (C) (saliva); home-care F(-) treatment (FD) (1,100 ppm F(-) dentifrice, 2x1 min/day); and professional (FVD) (22,600 ppm F(-) varnish) plus FD. The de-remineralisation was measured by transverse microradiography-TMR and hardness (surface hardness/cross-sectional hardness, SH/CSH, respectively). RESULTS: For SH, lesions produced by PA gel were the only one showing significant differences among the remineralising treatments (C x FD x FVD); while the TEMDP lesion were not responsive to any fluoride treatment (for both SH/CSH). For TMR, there were no differences among the remineralising treatments, regardless of the type of lesion. Generally, the most responsive lesions to fluoride were the less demineralised lesions (considering hardness: PA gel and Buffer). CONCLUSIONS: The type of lesion has influence on the surface remineralisation degree induced by home-care and professional fluoride treatments using this in situ model.
Asunto(s)
Cariostáticos/uso terapéutico , Esmalte Dental/patología , Dentífricos/uso terapéutico , Fluoruros/uso terapéutico , Remineralización Dental/métodos , Adolescente , Adulto , Estudios Cruzados , Atención Odontológica , Método Doble Ciego , Humanos , Higiene Bucal , Adulto JovenRESUMEN
Objetivo: Esse trabalho tem como objetivo determinar e diferenciar a erosão e o desgaste erosivo do esmalte induzidos pelos ácidos cítrico e clorídrico. Materiais e Métodos: Quarenta amostras de esmalte foram divididas em 2 grupos: 1) 0,05 M de ácido cítrico (pH 2,5) simulando a erosão extrínseca e 2) 0,01 M de ácido clorídrico (pH 2,2) simulando a erosão intrínseca. Amostras de esmalte foram submetidas aos desafios erosivos. A microdureza de superfície (erosão) ou a perfilometria (desgaste erosivo) foi realizada após 30 s, depois a cada 60 s até 10 min, depois a cada 5 min até 30 min e depois de 60, 90 e 120 min. Resultados: A erosão (perda de dureza do esmalte) foi mensurável até 1 e 2 min de exposição aos ácidos clorídrico e cítrico, respectivamente. O desgaste erosivo aumentou significativamente ao longo do tempo para ambos os ácidos. Após 8 min, o ácido cítrico foi mais agressivo comparado ao clorídrico (p < 0,001). Conclusão: A progressão da erosão do esmalte do amolecimento ao desgaste erosivo é altamente dependente do tipo de ácido, sendo o ácido cítrico mais agressivo em estágios avançados. Portanto, este resultado deve ser considerado na escolha do método de análise para estudos laboratoriais.
Objective: This study aimed to determine and differentiate erosive softening and enamel erosive loss induced by citric and hydrochloric acids. Material and Methods: Forty enamel specimens were divided into 2 groups: 1) 0.05 M citric acid (pH 2.5) simulating extrinsic erosion and 2) 0.01 M hydrochloric acid (pH 2.2) simulating intrinsic erosion. The enamel specimens were submitted to erosive challenges. Surface microhardness (softening) or contact profilometry (loss) was done after 30 s, after each 60 s up to 10 min, after each 5 min up to 30 min and after 60, 90 and 120 min. Results: Erosive softening (enamel hardness loss) was measurable up to 1 and 2 min for hydrochloric and citric acids, respectively. Erosive loss was significantly increased over time for both types of acids. After 8 min, citric acid was more aggressive than hydrochloric acid (p < 0.001). Conclusion: The progression of enamel erosion from erosive softening to erosive loss is highly dependent on the type of acid, being citric acid more aggressive in later stages. Therefore, this finding should be considered when choosing the method of analysis for laboratory studies
Asunto(s)
Esmalte Dental , Erosión de los Dientes , Desgaste de los DientesRESUMEN
OBJECTIVE: This in vitro study assessed the anti-erosive effect of experimental mouthrinses containing TiF4 and NaF on dentin erosive loss. MATERIAL AND METHODS: Bovine dentin specimens were randomly allocated into the groups (n=15): (1) SnCl2/NaF/AmF (Erosion Protection/GABA, pH 4.5, positive control); (2) experimental solution with 0.0815% TiF4(pH 2.5); (3) 0.105% NaF (pH 4.5); 4) 0.042% NaF+0.049% TiF4 (pH 4.4); (5) 0.063% NaF+0.036% TiF4 (pH 4.5); (6) no treatment (negative control). Each specimen was cyclically demineralized (Sprite Zero, pH 2.6, 4x90 s/day) and exposed to artificial saliva between the erosive challenges for 7 days. The treatment with the fluoride solutions was done 2x60 s/day, immediately after the first and the last erosive challenges of the day. Dentin erosive loss was measured by profilometry (µm). The data were analyzed using Kruskal Wallis/Dunn tests (p<0.05). RESULTS: Mouthrinses containing TiF4or Sn/F were able to show some protective effect against dentin erosive loss compared to negative control. The best anti-erosive effect was found for experimental solution containing 0.0815% TiF4 (100% reduction in dentin loss), followed by 0.042% NaF+0.049% TiF4 (58.3%), SnCl2/NaF/AmF (52%) and 0.063% NaF+0.036% TiF4 (40%). NaF solution (13.3%) did not significantly differ from control. CONCLUSION: The daily application of experimental mouthrinse containing TiF4 and NaF has the ability to reduce dentin erosion, as well as Erosion Protection and TiF4 alone.
Asunto(s)
Cariostáticos/química , Dentina/efectos de los fármacos , Fluoruros/química , Antisépticos Bucales/química , Fluoruro de Sodio/química , Titanio/química , Erosión de los Dientes/prevención & control , Animales , Bebidas Gaseosas , Bovinos , Fluoruros Tópicos/química , Concentración de Iones de Hidrógeno , Distribución Aleatoria , Reproducibilidad de los Resultados , Propiedades de Superficie , Factores de TiempoRESUMEN
Objective This in vitro study assessed the anti-erosive effect of experimental mouthrinses containing TiF4 and NaF on dentin erosive loss.Material and Methods Bovine dentin specimens were randomly allocated into the groups (n=15): 1) SnCl2/NaF/AmF (Erosion Protection®/GABA, pH 4.5, positive control); 2) experimental solution with 0.0815% TiF4(pH 2.5); 3) 0.105% NaF (pH 4.5); 4) 0.042% NaF+0.049% TiF4 (pH 4.4); 5) 0.063% NaF+0.036% TiF4 (pH 4.5); 6) no treatment (negative control). Each specimen was cyclically demineralized (Sprite Zero, pH 2.6, 4x90 s/day) and exposed to artificial saliva between the erosive challenges for 7 days. The treatment with the fluoride solutions was done 2x60 s/day, immediately after the first and the last erosive challenges of the day. Dentin erosive loss was measured by profilometry (μm). The data were analyzed using Kruskal Wallis/Dunn tests (p<0.05).Results Mouthrinses containing TiF4or Sn/F were able to show some protective effect against dentin erosive loss compared to negative control. The best anti-erosive effect was found for experimental solution containing 0.0815% TiF4 (100% reduction in dentin loss), followed by 0.042% NaF+0.049% TiF4 (58.3%), SnCl2/NaF/AmF (52%) and 0.063% NaF+0.036% TiF4 (40%). NaF solution (13.3%) did not significantly differ from control.Conclusion The daily application of experimental mouthrinse containing TiF4and NaF has the ability to reduce dentin erosion, as well as Erosion Protection® and TiF4 alone.
Asunto(s)
Animales , Bovinos , Cariostáticos/química , Dentina/efectos de los fármacos , Fluoruros/química , Antisépticos Bucales/química , Fluoruro de Sodio/química , Titanio/química , Erosión de los Dientes/prevención & control , Bebidas Gaseosas , Fluoruros Tópicos/química , Concentración de Iones de Hidrógeno , Distribución Aleatoria , Reproducibilidad de los Resultados , Propiedades de Superficie , Factores de TiempoRESUMEN
Este estudo avaliou o potencial de uma formulação experimental à base de HAP e fluoreto de sódio, para reduzir a desmineralização da dentina bovina in vitro. Oitenta e quatro amostras de dentina radicular bovina foram divididas em 7 grupos de 12 amostras, sendo submetidas a um dos seguintes tratamentos: 1) pasta Nanop plus [HAP a 20% + 9.000 ppm F, NaF); 2) pasta Nanop [HAP 20%); 3) pasta F [9.000 ppm F, NaF); 4) pasta placebo [sem HAP e F); 5) MI Paste [caseína e fosfato de cálcio); 6) MI Paste plus [caseína e fosfato de cálcio, 900 ppm F, NaF); 7) sem tratamento [controle). Os tratamentos foram realizados duas vezes ao dia, intercalados por ciclagem de pH (des-rernineralização], por 7 dias. Na sequência, as amostras foram analisadas por microdureza superficial e longitudinal (10-220 um). Os dados foram tabulados e submetidos à análise estatística [p<0,05). Em geral, os únicos tratamentos que tiveram efeito significativo na redução da desmineralização da dentina foram as pastas Nanop plus e F. Portanto, os dados confirmaram que o fluoreto ainda continua sendo o melhor agente químico para controlar a desmineralização dentária. Já a pasta experimental contendo nanopartículas de HAP foi ineficaz em reduzir a desmineralização da dentina utilizando-se o modelo experimental proposto
This study evaluated the potential of an experimental formulation containing HAP and sodium fluoride to reduce bovine dentin demineralization in vitro. Eighty-four bovine rools dentin samples were divided into 7 groups of 12 samples and subjected to one of the following treatments: 1) Nanop plus paste (HAP 20% + 9000 ppm F, NaF); 2) Nanop paste (HAP 20010) 3) F paste (9000 ppm F, NaF); 4) placebo paste (without HAP and F); 5) MI paste (casein and calcium phosphate); 6) MI Paste plus (casein and calcium phosphate, 900 ppm F, NaF); 7) no treatment (controll. The treatments were performed twice a day, interspersed by pH cycling (de-remineralization) for 7 days. Thereafter, the samples were analyzed using surface and cross-sectional microhardness (10-220 J.1m). The data was plotted and statistically analyzed (p<0.05). The treatments that produced a significant effect on the reduction of dentin demi neralization were Nanop plus and F pastes only. Therefore, the data confirmed that fluoride is still the best chemical agent to control dental demineralization. The experimental paste containing HAP nanoparticles was ineffective in reducing dentin demineralization when using this experimental model
Asunto(s)
Dentina , Desmineralización/análisis , FluorurosRESUMEN
Este trabalho avaliou o efeito do tipo de lesão cariosa artificial em esmalte produzido por quatros protocolos in vitro em relação ao potencial remineralizante in situ, utilizando como variáveis de resposta a microdureza superficial (SH) e longitudinal (CSH) e a microradiografia transversal (TMR). Para tal, 288 espécimes de esmalte bovino polidos (4x4mm) foram divididos de acordo com os valores de SH inicial em 4 tipos de protocolos desmineralizantes: Gel MC (gel de metilcelulose a 8%, ácido lático 0,1 M, pH 4,6, 14 dias); Gel PA (ácido poliacrílico 20g/L, ácido lático 0,1 M com hidroxiapatita a 500 mg/L, pH 4,8, 16h); Solução MHDP (ácido lático 50 mM, cálcio, fosfato e tetraetil metilenodifosfanato, pH 5,0, 6 dias) e Solução Tampão (ácido acético 50 mM, cálcio, fosfato e fluoreto, pH 5,0, 16h). Os espécimes desmineralizados foram tratados com agentes remineralizantes em um modelo in situ cruzado e duplo cego, com a participação de 12 voluntários que utilizaram aparelhos palatinos contendo 2 amostras de cada tipo de lesão de esmalte em cada fase, durante 3 fases experimentais com duração de 3 dias cada. Na fase da saliva humana, os voluntários realizaram o tratamento dos espécimes com dentifrício placebo (sem fluoreto, solução 1:3) ex vivo, 2x1min/dia. Na fase dentifrício fluoretado, o mesmo procedimento foi repetido em relação ao tratamento dos espécimes, porém utilizando o Dentifrício Crest (1.100 ppm F). Na fase verniz fluoretado, os mesmos procedimentos da fase dentifrício fluoretado foram repetidos, porém os espécimes foram tratados com verniz Duraphat (22.600 ppm F, 6h in vitro) anteriormente à fase in situ. Os dados foram submetidos à análise estatística (ANOVA ou similar não paramétrico e ANOVA a 2 critérios, p<0,05). Os diferentes protocolos desmineralizantes produziram lesões cariosas com perfis diferentes (resultados similares entre SH, CSH e TMR. Grau de desmineralização: Solução MHDP > Gel MC > solução Tampão = Gel PA) sendo nítida a diferença...
This study evaluated the effect of type of artificial enamel carious lesion produced by four in vitro protocols in respect to the remineralizing potential in situ, using as response variables: surface microhardness (SH), cross-sectional microhardness (CSH) and transverse microradiography (TMR). Thus, 288 polished enamel specimens (4x4mm) were divided according to the baseline SH values in 4 demineralizing protocols: MC gel (8% methylcellulose gel, 0.1 M lactic acid, pH 4.6, 14 days); PA gel (20g/L polyacrylic acid, 0.1 M lactic acid with 500 mg/L hydroxyapatite, pH 4.8, 16h); MHDP solution (50 mM lactic acid, calcium, phosphate and tetraethyl methylene diphosphanate, pH 5.0, 6 days) and Buffer Solution (50 mM acetic acid, calcium, phosphate and fluoride, pH 5.0, 16h). The demineralized specimens were treated with the remineralizing agents in an in situ model, with crossover and double-blind design. Twelve volunteers wore intra-oral appliances containing two specimens of each type of enamel lesion in each phase, during 3 experimental phases with duration of 3 days each. In the phase "human saliva", the volunteers performed the treatment of specimens with placebo toothpaste (no fluoride, solution 1:3) ex vivo, 2x1min/day. In phase "fluoride toothpaste", the same procedure was repeated, but using the toothpaste Crest (1100 ppm F). In the phase "fluoride varnish", the same procedures of the phase "fluoride toothpaste" were repeated, but the specimens were treated with Duraphat varnish (22600 ppm F, 6h in vitro) prior to the in situ phase. The data were submitted to statistical analysis (ANOVA or similar nonparametric test and 2-way ANOVA, p<0.05). The different demineralizing protocols produced artificial carious lesions with different profiles (similar results among SH, CSH and TMR. Degree of demineralization: MHDP solution> MC Gel > Buffer solution = PA Gel). There was a clear difference in the degree of remineralization between the diferente...
Asunto(s)
Animales , Bovinos , Caries Dental/inducido químicamente , Cariostáticos/química , Dentífricos/química , Esmalte Dental/química , Fluoruros/química , Saliva/química , Dentina , Dentina/química , Esmalte Dental , Pruebas de Dureza , Ensayo de Materiales , Valores de Referencia , Propiedades de Superficie , Factores de Tiempo , Remineralización DentalRESUMEN
Currently, it has been observed a significant increase in the prevalence of dental erosion as a consequence of frequent exposure to acids from foods, drinks and gastric juice. The aim of this review was to give some new insights about the definition and diagnosis of this condition, to clarify the causal factors and to show the preventive strategies and restorative therapy. Dental erosion is complex condition dependent on the interaction of chemical, biological and behavior factors. The diagnosis is generally performed by the analysis of the clinical appearance of the lesions in combination with the patients history. Some new technologies have been developed to help in early diagnosis and to quantify dental erosion in different phases. Preventive measures are established according to the causal factors, which may include the dietary intervention, modification of acidic drinks, and behavioral changes, or the modification of the tooth surface to increase its resistance against acidic attacks. The restorative treatment may range from minimally invasive therapies to multidisciplinary interventions. The clinicians should know how to detect the condition early, so that preventive measures can be applied before the lesions progress. Therapeutic strategies in high-risk patients should be as conservative as possible, involving multidisciplinary and preventive approaches with a periodic control for the success of the treatment.
Atualmente, tem-se observado um aumento significativo na prevalência de erosão dentária como consequência da exposição frequente aos ácidos oriundos de alimentos, bebidas e do suco gástrico. O objetivo desta revisão foi expor alguns novos direcionamentos sobre a definição e diagnóstico desta condição, esclarecer os fatores causais e apresentar as estratégias para a prevenção e o tratamento. A erosão dentária é uma condição complexa dependente da interação entre fatores químicos, biológicos e comportamentais. O diagnóstico é geralmente realizado por meio da análise da aparência clínica das lesões em combinação com a história do paciente. Novas tecnologias foram desenvolvidas para ajudar no diagnóstico precoce e para quantificar as diferentes fases da erosão dentária. As medidas preventivas são estabelecidas de acordo com os fatores causais que podem incluir a intervenção na dieta, modificação de bebidas ácidas, mudanças de comportamento, ou a modificação da superfície dentária com o objetivo de aumentar a sua resistência ao ataque ácido. O tratamento restaurador pode variar de terapias minimamente invasivas a intervenções multidisciplinares. Os clínicos devem saber como detectar a condição na sua fase inicial, para que medidas preventivas possam ser aplicadas antes da progressão da lesão. Estratégias terapêuticas em pacientes de alto risco devem ser as mais conservadoras possíveis, envolvendo abordagens multidisciplinares e preventivas com um controle periódico do paciente, para o sucesso do tratamento
Asunto(s)
Humanos , Epidemiología , Rehabilitación Bucal , Erosión de los DientesRESUMEN
Introdução e Objetivo: O motivo deste estudo foi avaliar a ação da Marapuama (Ptychopetatalum olacoides Benthan) nas alterações motoras induzidas pela droga reserpina em camundongos BalbC. Método: Foram utilizados doze camundongos Balb C, fêmeas, divididas em 2 grupos: controle (GC, n = 6 / 0,1 ml de solução oral,) e Marapuama (GM, n = 6 / 500mg/kg concentrada em 0,1 ml de solução oral por dia). A administração das soluções foi feita por gavagem durante 7 dias. Para a indução das alterações motoras semelhantes à Doença de Parkinson, os camundongos receberam por via intraperitoneal 1mg/Kg de resperpina (Sigma). A atividade motora foi avaliada pelo teste do Campo Aberto (BROADHURST,1960), 24 horas, 48 horas e 7 dias após a administração da reserpina. Para a análise estatística foi realizado o teste T-Student p ≤ 0,05. Resultados e discussão: os resultados obtidos mostraram que os camundongos tratados com Marapuama (Ptychopetatalum olacoides Benthan) apresentaram maior freqüência de locomoção do que os integrantes do grupo controle (GC). Quanto ao tempo de imobilidade, o grupo controle (GC) permaneceu mais tempo imóvel do que o grupo Marapuama (GM). A análise estatística mostrou-se significativa entrea comparação dos grupos nas primeiras 24 após a administração da reserpina. Conclusão: Concluiu-se que a fitoterápico Marapuma (Ptychopetatalum olacoides Benthan) apresentou a capacidade de aumentar a atividade motora dos animais sob ação da reserpina o que sugere uma possível capacidade de reduzir a bradicinesia que é um dos sintomas da doença de Parkinson.
Introduction and Objective: the aim of this study was to evaluate the action of Marapuama ( Ptychopetatalum olacoides Bentham ) in motor changes induced by reserpine in mice BalbC. Method: we used twelve Balb C female, divided into two groups: control group ( n = 6 / 0.1 ml of oral solution ) and Marapuama (GM, n = 6 / 500 mg / kg in 0.1 ml of concentrated oral solution per day). The drug administration was by gavage for 7 days. For the induction of motor disorders similar to Parkinson' s disease, the mice received intraperitoneal 1mg/kg resperpina (Sigma). The motor activity was evaluated by open test (BROADHURST, 1960), 24 hours, 48 hours and 7 days after administration of reserpine. For the statistical analysis was performed to test T-Student, p ≤ 0.05. Results and discussion: the results showed that mice treated with Marapuama ( Ptychopetatalum olacoides Bentham ) had higherfrequency of locomotion than members of the control group (CG). As for the immobility time, the control group ( CG ) remained immobile more time than the group Marapuama ( GM ). Statistical analysis was significant between the comparison groups in the first 24 after administration of reserpine. Conclusion: It was concluded that the phytotherapic Marapuma ( Ptychopetatalum olacoides Bentham ) had the ability to increase motor activity under the action of reserpine suggesting a possible ability to reduce bradykinesia, which is one of the symptoms of Parkinson' s disease.