Abstract Oral candidiasis is a common fungal infection that affects the oral mucosa, and happens when Candida albicans interacts with bacteria in the oral microbiota, such as Streptococcus mutans, causing severe early childhood caries. C. albicans and S. mutans mixed biofilms are challenging to treat with conventional antimicrobial therapies, thus, new anti-infective drugs are required. Objective This study aimed to test a drug delivery system based on chitosan microparticles loaded with geranium and lemongrass essential oils to inhibit C. albicans and S. mutans mixed biofilms. Methodology Chitosan microparticles loaded with essential oils (CM-EOs) were obtained by spray-drying. Susceptibility of planktonic were performed according CLSI at 4 to 2,048 µg/mL. Mixed biofilms were incubated at 37ºC for 48 h and exposed to CM-EOs at 256 to 4,096 µg/mL. The antimicrobial effect was evaluated using the MTT assay, with biofilm architectural changes analyzed by scanning electron microscopy. RAW 264.7 cell was used to evaluate compound cytotoxicity. Results CM-EOs had better planktonic activity against C. albicans than S. mutans. All samples reduced the metabolic activity of mixed C. albicans and S. mutans biofilms, with encapsulated oils showing better activity than raw chitosan or oils. The microparticles reduced the biofilm on the slides. The essential oils showed cytotoxic effects against RAW 264.7 cells, but encapsulation into chitosan microparticles decreased their toxicity. Conclusion This study demonstrates that chitosan loaded with essential oils may provide an alternative method for treating diseases caused by C. albicans and S. mutans mixed biofilm, such as dental caries.

Abstract Objective: To evaluate in vitro erosive effect of analgesics on primary tooth enamel. Material and Methods: The pH and the titratable acidity measurements of the medicines were performed in triplicate using a digital pH meter. Enamel slabs of primary teeth flat and polished were selected by initial surface microhardness analysis. Medications were selected and specimens were assigned into five groups (n=12): Dalsy; Magnopyrol; Paracetamol; Tylenol; and distilled water (negative control). Specimens were immersed in 5 ml of each group solution for 30 min, 4x/day for three days and stored in artificial saliva at 37 °C between immersions and at night. Final microhardness was determined. The data were submitted to Oneway ANOVA and Tukey's test. Scanning electron microscopy (SEM) analysis was performed in three specimens of each group. Results: Medicines showed acidic pH and mean values of titratable acidity ranged from 1.46 to 11.66 ml of 0.1N NaOH. The mineral loss of Magnopyrol was statistically significant in relation to the control group (p<0.01). Magnopyrol showed higher values when compared to Tylenol (p<0.05). SEM images displayed microstructure alterations in the Paracetamol group. Conclusion: Despite the low pH values, only Magnopyrol showed greater enamel softening. Paracetamol demonstrated morphological changes in primary tooth enamel.

Abstract This research explored the potential of Camellia sinensis-derived teas and active compounds to be used as treatments to prevent dentin wear. Human root dentin slabs were randomly assigned to 5 groups (n = 10) as follows: distilled water (DW, control), epigallocatechin-3-gallate (EGCG), theaflavin gallate derivatives (TF), commercial green tea (GT), and commercial black tea (BT). The samples were submitted to a pellicle formation and an erosive cycling model (5x/day, demineralization using 0.01 M hydrochloric acid/60 s) followed by remineralization (human stimulated saliva/60 min) for three days. The samples were treated for 5 min using the test group solutions between the erosive cycles. Dentin changes were assessed with profilometry analysis and FT-Raman spectroscopy. The data regarding wear were analyzed by ANOVA followed by Tukey's test (p < 0.05). EGCG, TF derivatives, and both regular teas significantly suppressed erosive dentin loss (38–47%, p < 0.05). No obvious changes in the Raman spectra were detected in the specimens; however, the DW group had a minor relationship of 2880/2940 cm−1. The phenolic contents in both green and black tea and the important catechins appear to have protective effects on dentin loss.

The aim of this in vitro study was to assess the root dentin demineralization caused by a microcosm biofilm model that has been exposed to sucrose in different ways. Materials and Methods: Saliva of two volunteers was inoculated into an artificial medium for biofilm growth and dentin blocks were immersed into these media. Dentin specimens were randomly exposed to one of the five experimental conditions: C (control group - no saliva inoculum or sucrose), 0S (saliva inoculum without sucrose, negative control), 3S (three daily one-minute immersions in 20 % sucrose), 6S (six daily one-minute immersions in 20 % sucrose), and CS (continuously immersed in 5 % sucrose). After five days, biofilm was collected to determine the concentration of intracellular and extracellular polysaccharides and the dentin surface hardness loss (SHL) was measured. The experiment was carried out in triplicate. Results: The dentin SHL was higher in groups that were exposed to sucrose (3S, 6S and CS) and there was a statistically significant difference between all groups (p<0.001). CS had higher concentrations of polysaccharides (p>0.001) and there was no statistically significant difference between the other groups (0S, 3S and 6S) (p>0.005). Conclusion: The microcosm biofilm model developed has the potential to produce root dentin demineralization at different exposures to sucrose.

El objetivo de esta investigación in vitro fue evaluar la desmineralización de la dentina radicular causada por un modelo de biofilm microcosmo que fue expuesto de diferentes maneras a la sacarosa. La saliva de dos voluntarios fue colocada en un medio artificial para crecimiento del biofilm y los bloques de dentina fueron sumergidos en estos medios. Al aza rlos bloques fueron expuestos a una de las cinco condiciones experimentales: C (grupo control sin inoculación de saliva o sacarosa), 0S (inoculación de saliva sin sacarosa, control negativo), 3S (tres inmersiones diarias de un minuto en sacarosa a 20 %), 6S (seis inmersiones diarias de un minuto en sacarosa a 20 %), y CS (sumergidos continuamente en 5 % de sacarosa). Después de cinco días, el biofilm fue recogido para determinar la concentración de polisacáridos intracelulares y extracelulares y fue medida la pérdida de dureza superficial de la dentina (SHL). El experimento se repitió en tres ocasiones. La dentina SHL era mayor en los grupos que fueron expuestos a la sacarosa (3S, 6S E CS) y hubo diferencia estadísticamente significativa entre todos los grupos (P<0,001). CS presentó mayor concentración de polisacáridos (p<0,001) y no hubo diferencia estadísticamente significativa entre los demás grupos (0S, 3S E 6S) (p>0,005). El modelo del biofilm desarrollado tiene potencial para producir desmineralización de la dentina radicular en diferentes exposiciones a la sacarosa.

This study evaluated the effect of a 2% chlorhexidine-based disinfectant (CHX) on the short-term resin-dentin bond strength of a self-etch adhesive system to human dentin with different mineral contents. Dentinal mineralization was tested at 4 levels (sound, and after 2, 4, or 8 days of demineralization-remineralization cycles) and disinfectant at 2 levels [deionized water (DW, negative control) and CHX]. Dentin demineralization induced by pH-cycling was characterized by cross-sectional hardness (CSH). Each dentin surface was divided into halves, one treated with DW and the other with CHX (5 minutes). Each surface was bonded with a self-etch adhesive system and restored. The specimens were sectioned and subjected to microtensile bond testing. CSH and microtensile bond strength (µTBS) data were analyzed by regression analysis and ANOVA-Tukey tests (α = 5%), respectively. The groups treated with CHX resulted in mean µTBS similar to those found for the groups in which the dentin was exposed to DW (p = 0.821). However, mean µTBS were strongly influenced by dentin mineralization (p < 0.05): the bond strength found for sound dentin was lower than that found for dentin cycled for 8 days, which was even lower than the bond strengths for dentin cycled for 2 or 4 days. The results suggest that the degree of dentin demineralization affects the bond strength of self-etching adhesives, but the use of CHX does not modify this effect.

OBJETIVO: Avaliar a eficácia da remoção de lama dentinária por agentes de limpeza cavitária através da análise de microscopia de força atômica (MFA). METODOLOGIA: Cinco terceiros molares humanos hígidos foram seccionados transversalmente na porção coronária, obtendo discos de dentina de 2 mm, que foram desgastados com lixas de granulação 600, por 10 s.Foram feitos cortes seriados longitudinais e perpendiculares entre si, obtendo-se quarto espécimes de cada dente. Os espécimes foram divididos em 4 grupos: GI- clorexidina a 2%; GII- água de hidróxido de cálcio; GIII- solução fluoretada a 1,23%; GIV - ácido fosfórico 37%. As soluções foram aplicadas com pincel por 60 s, com exceção do ácido fosfórico que foi aplicado por 15 s e lavado com água destilada pelo mesmo tempo. Os espécimes foram analisados por MFA. RESULTADOS: Todos os espécimes de GI e GII apresentaram 100 % dos túbulos dentinários obliterados por lama dentinária. Os espécimes de GIII e GIV apresentaram 0 % dos túbulos obliterados por lama dentinária. CONCLUSÃO: A solução de fluoretada a 1,23 % foi eficiente na remoção de lama dentinária, podendo ser empregada na limpeza de cavidades.

PURPOSE: To evaluate the efficacy of smear layer removal by cavity cleaning agents by the use of atomic force microscopy (AFM). METHODS: Five intact human third molars were sectioned in the coronal portion to obtain dentin disks, which were ground with 600-grit abrasive paper for 10 s. Serial longitudinal sections were made perpendicular to each other to create four specimens, from each tooth. The specimens were divided into four treatment groups: GI, 2% chlorhexidine; GII, calcium hydroxide solution; GIII, 1.23% fluoride solution; and GIV, 37% phosphoric acid. The solutions were applied with a brush for 60 s, with the exception of the 37% phosphoric acid, which was applied for 15 s and rinsed with distilled water for 60 s. The specimens were examined by AFM. RESULTS: All of the specimens in GI and GII showed 100% of the dentin tubules obliterated by the smear layer. However, all of the specimens in GIII and GIV showed 0% of the dentin tubules obliterated by the smear layer. CONCLUSION: The 1.23% fluoride solution was effective in removing the smear layer and can be used as a cavity cleanser.

O objetivo desse estudo foi avaliar a eficiência de dois agentes dessensibilizantes na redução da hipersensibilidade dentinária, em um estudo clínico aleatório do tipo boca-dividida e duplo-cego. Setenta e sete dentes de 13 pacientes que apresentavam algum grau de sensibilidade à sondagem e/ou estímulo ao ar foram tratados com um dos seguintes agentes dessensibilizantes: Oxa-Gel (G1), Sensi Kill (G2) e gel placebo (G3-controle). De acordo com o teste t pareado, todos os tratamentos, inclusive o placebo, foram capazes de reduzir os escores para ambos os estímulos. A análise dos dados pelos testes de ANOVA e de Tukey (?=0,05) demonstrou que os escores de sensibilidade foram significantemente menores somente para o Sensi-Kill em comparação aos outros produtos (Oxa-Gel e placebo) quando o estímulo ar foi aplicado. Pode-se concluir que o tratamento com Sensi-Kill apresentou um desempenho ligeiramente melhor na redução da hipersensibilidade dentinária quando comparados aos outros agentes dessensibilizantes.

The aim of this study was to evaluate the efficacy of two desensitizing agents in the reduction of dentin hypersensitivity in a randomized, double-blind, split-mouth clinical trial. Seventy-seven teeth from 13 patients that presented some degree of sensitivity to probing and/or air stimulation were treated with one of the following desensitizing agents: Oxa-Gel (G1), Sensi Kill (G2) and placebo gel (G3 - control). According to paired t-test, all treatments, even the placebo gel, were capable of reducing sensitivity scores for both stimuli. Analysis of data by ANOVA and Tukey's test (?=0.05) showed that the sensitivity scores were significantly lower only for Sensi Kill in comparison to the other products (Oxa-Gel and placebo), when air stimulus was applied. It may be concluded that treatment with Sensi Kill presented a slightly better performance in reducing dentin hypersensitivity when compared to the other desensitizing agent.

OBJECTIVES: The aim of this study was to determine the effect of environmental conditions on the degradation of ionomeric and resin sealant materials. MATERIAL AND METHODS: FluroShield, Vitremer, and Ketac Molar disc-shaped specimens (n=18/material) were prepared, polished, subjected to initial hardness and roughness readings. Six discs of each material were randomly assigned to one of three different storage solutions: 0.3% citric acid (CA), demineralization solution (DE), and remineralization solution (RE). The specimens were individually immersed in 3 mL of the test solutions, which were daily changed. After 15 days of storage, new surface roughness and hardness readings were done. Fluoride release in the solutions was measured within 15 days. Data were analyzed by ANOVA and Tukey's and Contrast tests (α=0.05). RESULTS: The storage in CA increased the roughness of Vitremer and Ketac Molar. A significant reduction in hardness was observed for all materials after storage in all solutions. For all materials, the greatest amounts of fluoride release occurred during the 1st day. FluroShield presented the same patterns of fluoride release in all solutions. Ketac Molar and Vitremer released the highest amounts of fluoride in the CA solution. CONCLUSIONS: Ionomeric materials are more susceptible to degradation than resin-based materials under acidic conditions. Acidic conditions lead to a higher fluoride release from ionomeric materials.

Dentes humanos extraídos são freqüentemente utilizados para propósitos educacionais ou de pesquisa. Desta forma, é necessário o armazenamento dos mesmos em soluções desinfetantes que não alterem a estrutura dental. Para tanto, sessenta espécimes foram divididos nos seguintes grupos: esmalte armazenado em formol (F1), armazenado em timol (T1), armazenado em formol e submetido à ciclagem de pH (F2) e armazenado em timol e submetido à ciclagem de pH (T2), sendo avaliados por meio de análise de microdureza longitudinal e tiveram a porcentagem de volume mineral pro micrômetro determinada. Diferenças entre os grupos foram encontradas até a profundidade de 30µm da superfície do esmalte (p<0,05), onde o grupo mais desmineralizado era T2. Foi concluído que a solução de armazenagem influenciou na reação do substrato dental a um desafio cariogênico, sugerindo que o formaldeído pode aumentar a resistência do esmalte à desmineralização promovida pelo modelo de ciclagem de pH, quando comparado à desmineralização ocorrida no esmalte armazenado em timol.

Extracted human teeth are frequently used for research or educational purposes. Therefore, it is necessary to store them in disinfectant solutions that do not alter dental structures. Thus, this study evaluated the influence of storage solution on enamel demineralization. For that purpose, sixty samples were divided into the following groups: enamel stored in formaldehyde (F1), stored in thymol (T1), stored in formaldehyde and submitted to pH cycling (F2), stored in thymol and submitted to pH cycling (T2). All samples were evaluated by cross-sectional microhardness analysis and had their percentage of mineral volume versus micrometer (integrated area) determined. Differences between groups were found up to 30-µm depth from the enamel surface (p < 0.05), where samples from group T2 were more demineralized. It was concluded that the storage solution influenced the reaction of a dental substrate to a cariogenic challenge, suggesting that formaldehyde may increase enamel resistance to demineralization, when compared to demineralization occurring in enamel stored in thymol solution.

A percepção da fluorose dental e seu impacto em escolares de Piracicaba, SP, Brasil, expostos ao uso de flúor pela água e dentifrício, foram avaliados. O problema foi encontrado em 72% das crianças, mas o grau de alteração decorrente não provocou nenhum impacto na satisfação das crianças com seus dentes. Embora a fluorose dental, devido à ingestão de flúor pela água e ao uso de dentifrício fluoretado, não tenha comprometido a estética da amostra populacional avaliada, estudo mais abrangente deve ser realizado.

The impact of dental fluorosis in children exposed to fluoride in drinking water and dentifrice was evaluated. Dental fluorosis was found in 72% of the children, but the children's well-being was not affected. It was concluded that although dental fluorosis due to the intake of optimally fluoridated drinking water and dentifrice did not affect the dental aesthetics of this studied population sample, there is a need of further studies on the subject.

A percepção da fluorose dental e seu impacto em escolares de Piracicaba, SP, Brasil, expostos ao uso de flúor pela água e dentifrício, foram avaliados. O problema foi encontrado em 72% das crianças, mas o grau de alteração decorrente não provocou nenhum impacto na satisfação das crianças com seus dentes. Embora a fluorose dental, devido à ingestão de flúor pela água e ao uso de dentifrício fluoretado, não tenha comprometido a estética da amostra populacional avaliada, estudo mais abrangente deve ser realizado.

The impact of dental fluorosis in children exposed to fluoride in drinking water and dentifrice was evaluated. Dental fluorosis was found in 72% of the children, but the children's well-being was not affected. It was concluded that although dental fluorosis due to the intake of optimally fluoridated drinking water and dentifrice did not affect the dental aesthetics of this studied population sample, there is a need of further studies on the subject.