Effect of phenylmethylsulfonyl fluoride, a protease inhibitor, on enamel surface remineralization

Phenylmethylsulfonyl fluoride (PMSF) is a protease inhibitor widely used in research, but fluoride is released during its action and this knowledge has been neglected in dental research. Aim: to evaluate if fluoride released by salivary protease action on PMSF affects enamel remineralization and fluoride uptake. Methods: Groups of 10 enamel slabs, with caries-like lesions and known surface hardness (SH), were subjected to one of the following treatment groups: Stimulated human saliva (SHS), negative control; SHS containing 1.0 µg F/mL (NaF), positive control; and SHS containing 10, 50 or 100 µM PMSF. The slabs were subjected to a pH-cycling regimen consisting of 22 h/day in each treatment solution and 2 h/day in a demineralizing solution. After 12 days, SH was again measured to calculate the percentage of surface hardness recovery (%SHR), followed by enamel fluoride uptake determination. The time-related fluoride release from 100.0 µM PMSF by SHS action was also determined. Data were analyzed by ANOVA followed by Newman-Keuls test. Results: The release of fluoride from PMSF by SHS was rapid, reaching a maximum value after 10 min. Fluoride released from PMSF was more effective in enhancing %SHR and increasing fluoride uptake in enamel compared with SHS alone (p < 0.05); furthermore, it was equivalent to the positive control (p > 0.05). Conclusion: In conclusion, fluoride released by saliva from PMSF is available to react with enamel and needs to be taken into account in research using this protease inhibitor

In vitro antifungal action of different substances over microwaved-cured acrylic resins

OBJECTIVE: The presence of Candida albicans on the surfaces of denture-base acrylic resins is strongly related to the development of oral stomatitis. This study evaluated the antifungal action of different agents over microwave-cured acrylic resin without polishing specimens previously contaminated with Candida albicans. MATERIAL AND METHODS: Sixty specimens were immersed in BHI broth previously inoculated with the yeast and stored for 3 h at 37ºC. They were divided into 5 experimental groups (n=10): G1: 2 percent chlorhexidine solution (10 min); G2: 0.5 percent sodium hypochlorite (10 min); G3: modified sodium hypochlorite (10 min); G4: effervescent agent (5 min); G5: hydrogen peroxide 10v (30 min). The specimens of the control group 1 (C1) were not disinfected. Ten additional specimens of the control group 2 (C2) were not infected with the yeast, aiming to check the asepsis during the experiment. The disinfection agents were neutralized and the acrylic resin specimens were immersed in BHI Broth for 24 h. Culture media turbidity was evaluated spectrophotometrically according to the transmittance degree, i.e. the higher the transmittance the stronger the antimicrobial action. Statistical analysis was performed (Kruskal-Wallis Test, p<0.05). RESULTS: The results, represented by the medians, were: G1 = 40; G2 = 100; G3 = 100; G4 = 90; G5 = 100; C1 = 40; C2 = 100. CONCLUSIONS: This in vitro study suggested that sodium hypochlorite-based substances and hydrogen peroxide are more efficient disinfectants against C. albicans than 2 percent chlorhexidine solution and the effervescent agent.

Análise in vitro da eficácia do bicarbonato de sódio e da nistatina na inibição de Candida albicans / In vitro analysis of the effectiveness of nistatina and sodium bicarbonate in the inhibition of Candida albicans

A cavidade oral alberga uma grande variedade de microrganismos, sendo que o equilíbrio entre microbiota bucal e hospedeiro pode ser alterado, favorecendo a patogenicidade, por parte de microorganismo. É em pacientes imunodeprimidos por HIV e por câncer que nas últimas décadas pude-mos perceber as manifestações da candidíase oral. O trabalho visou à verificação da ação antifúngica da Nistatina, solução de bicarbonato de sódio a 30% e dentifrício com bicarbonato de sódio, através datécnica de difusão em Ágar com posterior leitura do halo de inibição, constatando qual desses agentes émais efetivo no tratamento da candidíase oral. Nos resultados, houve uma similaridade da eficácia dasolução de bicarbonato de sódio e da Nistatina quanto à inibição do crescimento de Candida albicans.O dentifrício contendo bicarbonato de sódio produziu discreta inibição. Assim, constatou-se que asolução de bicarbonato de sódio apresenta, in vitro, uma eficácia semelhante à Nistatina, aliando custo reduzido e eficácia clínica.

The oral cavity lodges a great variety of microorganisms, being that the buccal balance microbiota and host can be modified, favoring the pathogenicity on the part of the microorganisms. It is patients immunedejectedes for HIV and cancer that in the last decades we could perceive the manifestations of oral candidiasis. The work aimed at the verification of the antifungal action of the Nistatina, sodium bicarbonate solution 30% and dentifrice with sodium bicarbonate, through the technique of diffusion inAgar with posterior reading of the inhibition halo, evidencing which is more effectiveness of sodium bicarbonate and the Nistatina how much to the inhibition of the growth of Candida albicans. The dentifrice contend bicarbonate produced discrete inhibition. Thus, in was evidenced that sodium bicarbonate presents, in vitro, a similar effectiveness to the Nistatina, uniting reduced cost and clinical effectiveness.

Efeito de um dentifrício fluoretado contendo bicarbonato de sódio na contagem de estreptococos do grupo mutans, acidogenicidade e composiçäo da placa dental / Effect of a fluorated dentifrice containing baking soda on mutans counting, acidogenicity and dental plaque composition

Avaliou-se o efeito de um dentifrício contendo bicarbonato de sódio na contagem de estreptococos do grupo mutans (EM), acidogenicidade e composiçäo da placa dental. Vinte e três voluntários escovaram os dentes 3 vezes ao dia, com formulaçöes fluoretadas (1.500 ppm F), contendo, ou sílica (SÍLICA), ou carbonato de cálcio (CARBONATO), ou carbonato de cálcio mais bicarbonato de sódio (CARB/BICAR), num delineamento duplo cego cruzado, com 3 etapas de 30 dias. No 28§ dia, 8 a 12 horas após a última escovaçäo, foi realizada a contagem de estreptococos do grupo mutans na saliva (EMS). No 30§ dia (após 2 dias, nos quais os voluntários bochecharam 3 vezes/dia uma suspensäo do dentifrício em água, e 6 vezes/dia sacarose a 10 por cento), analisou-se na placa dental, após 10 a 12 horas do último bochecho de dentifrício: a) contagem de mutans (EMP); b) polissacarídeos álcali solúveis (PSA); c) flúor solúvel em ácido (FSA); d) pH no tempo zero (T(0)), após 5 minutos de bochecho com sacarose (T(5)), calculando-se o DELTApH (T(0)-T(5))...