Efeito de dentifrícios com alta concentração de flúor na remineralização de substrato dentário com cárie artificial / Effect of toothpaste with high fluoride concentration on remineralization of dental substrate with artificial caries

Introduction: fluoride toothpaste is widely used by the population. Objective: dentifrices with a high concentration of sodium fluoride and the presence of tricalcium phosphate were developed, providing additional protection to patients vulnerable to the development of caries. This study aimed to evaluate the influence of different dentifrices on the surface and internal hardness and enamel wear after artificial caries, pH cycling, and toothbrushing. Material and method: enamel blocks (4x4 mm) were obtained from 20 bovine teeth. The specimens were submitted to artificial caries lesion and then to pH cycling and brushing according to the dentifrice: Colgate Total 12 and Clinpro + Tricalcium Phosphate. Result: after this period, they were submitted to analysis of superficial and internal hardness and profilometry. Scanning Electron Microscopy (SEM) was performed. The data obtained were evaluated by one-way Analysis of Variance (ANOVA) to evaluate the mineral recovery and profilometry, and two-way repeated measures ANOVA to evaluate the superficial and internal hardness. Conclusion: analyzing the surface hardness, after caries induction, there was a significant reduction in hardness that was partially recovered regardless of the dentifrice used. For internal hardness, Clinpro obtained lower values on the control side and up to 90 micrometers on the test side. As for profilometry, Colgate Total 12 showed greater wear when compared to Clinpro. It was concluded that Clinpro promoted lower internal hardness, however, Colgate Total 12 resulted in greater surface wear of tooth enamel.

Introdução: dentifrícios fluoretados são amplamente utilizados pela população. Foram desenvolvidos dentifrícios com alta concentração de fluoreto de sódio e presença de tricálcio fosfato, fornecendo proteção adicional a pacientes vulneráveis ao desenvolvimento da cárie. Objetivo: o objetivo deste estudo foi avaliar a influência de diferentes dentifrícios na dureza superficial, interna e desgaste do esmalte após cárie artificial, ciclagem de pH e escovação. Material e método: blocos de esmalte (4x4 mm) foram obtidos a partir de 20 dentes bovinos. Os espécimes foram submetidos à lesão de cárie artificial e, em seguida, à ciclagem de pH e escovação de acordo com o dentifrício: Colgate Total 12 e Clinpro + Tricálcio Fosfato. Após este período, foram submetidos à análise de dureza superficial e interna e perfilometria. Foi realizada microscopia eletrônica de varredura. Resultado: os dados obtidos foram avaliados por ANOVA um critério para avaliar a recuperação mineral e perfilometria, ANOVA dois critérios medidas repetidas para avaliar a dureza superficial e interna. Conclusão: analisando a dureza superficial, após a indução da cárie houve uma redução significativa na dureza que foi parcialmente recuperada independente do dentifrício utilizado. Para dureza interna, Clinpro obteve valores menores no lado controle e até 90 micrômetros no lado teste. Quanto à perfilometria, o Colgate Total 12 apresentou maior desgaste quando comparado ao Clinpro. Concluiu-se que Clinpro promoveu menor dureza interna, porém, o Colgate Total 12 resultou em maior desgaste superficial do esmalte dentário.

Efeito de dentifrício com alta concentração de flúor na remineralização e resistência de união de cimento de ionômero de vidro em substratos dentários com cárie artificial / Effect of dentifrice with high concentration of fluoride under remineralization and bond strength of glass ionomer cement on dental substrates with artificial caries

O objetivo do presente estudo foi avaliar a influência de diferentes dentifrícios na dureza de superfície, em secção transversal e perfil de desgaste do esmalte, assim como na resistência de união de cimentos de ionômero de vidro de alta viscosidade (CIV-AV) à dentina, após indução de cárie artificial, ciclagem de pH e escovação. Foram utilizados 80 dentes bovinos, divididos em blocos de esmalte e dentina. Os espécimes de esmalte foram polidos e selecionados de acordo com a microdureza. Em seguida, metade de cada bloco de esmalte foi protegida com verniz ácido resistente. Os espécimes de dentina foram incluídos em resina acrílica e planificados. O protocolo de cárie artificial foi feito através de ciclos de desmineralização em esmalte (n=20) e pela imersão da dentina (n=40) em solução desmineralizadora. Vinte amostras de dentina não foram submetidas à cárie, sendo o grupo controle. Todas as amostras foram submetidas à ciclagem de pH e escovação durante 7 dias de acordo com cada dentifrício: Colgate Total 12 1450 ppm F (CT) e Clinpro 5000 ppm F + TCP (CL). Em seguida, os blocos de esmalte foram submetidos às análises de dureza de superfície, em secção transversal e perfilometria. Microscopia eletrônica de varredura foi realizada em três blocos representativos de cada grupo. Os espécimes de dentina foram subdivididos de acordo com material restaurador: CIV-AV Ketac Molar (KM) e cimento ionomérico híbrido Equia Forte (EF). Em seguida, as amostras foram armazenadas sob umidade relativa durante 24 horas e preparados para o teste de microcisalhamento. Os dados obtidos foram submetidos ao teste de normalidade, análise de variância (ANOVA) 1 critério para avaliar a recuperação mineral e perfil de desgaste, ANOVA 2 critérios com medidas repetidas para avaliar a dureza de superfície e em secção transversal, ANOVA 3 critérios para avaliar o microcisalhamento e pós teste de Tukey para comparações múltiplas, com significância de 5%. Observou-se recuperação parcial da dureza de superfície, independente do dentifrício. Os dados da dureza em secção transversal evidenciaram que CL obteve valores inferiores a CT até 90 micrômetros (m) no lado teste. O dentifrício CT apresentou maior desgaste quando comparado à CL. Em dentina, ao comparar os dentifrícios dentro de cada CIV, CT apresentou maior resistência adesiva para ambos os materiais. A comparação entre CIVs dentro do mesmo dentifrício evidenciou resistência adesiva superior para KM quando comparado à EF na dentina tratada com CL. Conclui-se que o dentifrício com maior concentração de flúor promoveu menor dureza em secção transversal no esmalte e o dentifrício convencional resultou em maior desgaste superficial. Na superfície dentinária, o dentifrício com maior concentração de flúor diminuiu a resistência adesiva de cimentos de ionômero de vidro(AU)

The aim of the present study was to evaluate the influence of different dentifrices on surface hardness and cross-sectional hardness, wear profile on enamel, as well as on the bond strength of high viscosity glass ionomer cements (HV-GIC) to dentin, after to produce artificial caries, pH cycling and brushing. Eighty bovine teeth were used, divided into enamel and dentin blocks. The enamel specimens were polished and selected according to microhardness. Then, half of each enamel block was covered with resistant acid varnish. Dentin specimens were embedded in acrylic resin and flattened. The artificial caries protocol was carried out through enamel demineralization cycles (n= 20), and the dentin (n= 40) was immersed in demineralizing solution. Twenty dentin specimens were not subjected to artificial caries, being the control group. All blocks were subjected to pH cycling and brushing for 7 days according to each dentifrice: Colgate Total 12 1450 ppm F (CT) and Clinpro 5000 ppm F + TCP (CL). Then, the protected enamel surfaces were exposed for the analysis of surface hardness, cross sectional hardness and profilometry. Scanning electron microscopy was performed in three representative blocks of each group. The dentin specimens were subdivided according to restorative material: HVGIC Ketac Molar (KM), and hybrid GIC Equia Forte (EF). Then, the specimens were stored under relative humidity for 24 hours and prepared for the micro-shear test. The data were submitted to normality test, one-way analysis of variance (ANOVA) to assess mineral recovery and wear, two-way repeated measures ANOVA to assess surface and cross-sectional hardness, and three-way ANOVA to analyze the bond strength. Tukey post-test was used for multiple comparisons, with a significance level of 5%. It was observed a partial recovery of superficial microhardness, regardless of the dentifrice. Cross sectional hardness data showed that CL obtained values below CT up to 90 micrometers (m) on the test side. CT dentifrice presented greater wear when compared to CL. In dentin, when the dentifrices were compared within each GIC, CT showed greater adhesive resistance for both materials. A comparison between GICs within the same dentifrice showed superior adhesive resistance for KM when compared to EF in dentin treated with CL. It was concluded that the dentifrice with the highest fluoride concentration promoted less cross-sectional hardness in the enamel and the conventional dentifrice resulted in greater surface wear. On the dentin, the dentifrice with the highest fluoride concentration decreased the adhesive strength of glass ionomer cements(AU)

Three-year evaluation of different adhesion strategies in non-carious cervical lesion restorations: a randomized clinical trial

Abstract: Objective: To evaluate non-carious cervical lesions (NCCLs) restored with different adhesion strategies. Methodology: This is a prospective, randomized, double-blind, split-mouth study. An adhesive restorative system (Single Bond Universal/Filtek Z350XT - SBU) was evaluated both without and with selective enamel conditioning (E-SBU), resin-modified glass-ionomer cements (Vitremer; RMGIC), and ethylenediaminetetraacetic acid pretreatment (EDTA; E-RMGIC). In total, 200 restorations, placed in 50 patients, were evaluated at baseline and at a 3-year follow-up using the modified United States Public Health Service (USPHS) criteria. Data were analyzed using the two-proportion equality test, multinomial logistic regression, Wilcoxon test, and Kaplan-Meier survival curves. Results: In total, 42 (84%) patients returned for the 3-year follow-up. SBU showed restoration losses statistically different from RMGIC. Retention was also statistically different in SBU between baseline and the 3-year follow-up. Marginal defects and surface texture were statistically significant for all groups in the period studied, except for the surface texture of SBU and the marginal integrity in E-RMGIC. We observed no statistically significant difference in wear, secondary caries, anatomical form, surface staining, and color over time. Recession degree was the only factor to influence retention rates. Cumulative survival (%) was 89, 98, 98, and 95.3, for SBU, SE-SBU, RMGIC, and E-RMGIC, respectively, without significant differences among them. There was a statistically significant difference between survival curves; however, multiple comparison procedures found no statistical differences. Conclusion: Selective enamel etching affected the retention of non-carious cervical restorations. Adhesion using EDTA and resin-modified glass-ionomer cements delayed marginal defects over time. The degree of gingival recession influenced retention rates. Resin composite restorations showed initial marginal defects, and ionomer restorations, reduced surface luster. EDTA pre-treatment followed by resin-modified glass-ionomer cements may be a promising adhesion strategy for NCCL restorations.

Effects of different toothpastes on the prevention of erosion in composite resin and glass ionomer cement enamel and dentin restorations

Abstract Objective This study aimed to evaluate the effects of different toothpastes on the surface wear of enamel, dentin, composite resin (CR), and resin-modified glass ionomer cement (RMGIC), and to perform a topographic analysis of the surfaces, based on representative images generated by atomic force microscopy (AFM) after erosion-abrasion cycles. Methodology One hundred and forty bovine incisors were collected and divided into two groups: 72 enamel and 72 dentin blocks (4×4 mm). Half of the specimens were restored with CR (Filtek Z350 XT) and the other half with RMGIC (Fuji II LC). Then, samples were submitted to a demineralization cycle (5 days, 4×2 min/day, 1% citric acid, pH 3.2) and exposed to three different toothpastes (2×15 s/day): without fluoride (WF, n=12), sodium fluoride-based (NaF, n=12), and stannous fluoride-based (SnF2, n=12). Surface wear, as well as restoration interfaces wear, were investigated by profilometry of the dental substrates and restorative materials. All representative surfaces underwent AFM analysis. Data were analyzed by two-way analysis of variance and Tukey's tests (α=0.05). Results NaF-based toothpaste caused the greater dentin surface wear (p<0.05). Toothpastes affected only enamel-restoration interfaces. AFM analysis showed precipitate formation in dentinal tubules caused by the use of fluoride toothpastes. Conclusions NaF-based toothpastes had no protective effect on enamel adjacent to CR and RMGIC against erosion-abrasion challenges, nor on dentin adjacent to RMGIC material. SnF2-based toothpastes caused more damage to interfaces between enamel and RMGIC.