Pomegranate extract in polyphosphate-fluoride mouthwash reduces enamel demineralization.

OBJECTIVES: To evaluate the anti-demineralizing effect of a mouthwash comprising pomegranate peel extract (PPE 3%), sodium trimetaphosphate (TMP 0.3%), and fluoride (F 225 ppm) in an in situ study, and to assess its irritation potential in an ex vivo study. METHODS: This double-blind crossover study was conducted in four phases with 7 days each. Twelve volunteers used palatal appliances containing enamel blocks, which were subjected to cariogenic challenges. The ETF formulation (PPE + TMP + F, pH 7.0), TF formulation (TMP + F, pH 7.0), deionized water (W, pH 7.0), and essential oil commercial mouthwash (CM, 220 ppm F, pH 4.3) were dropped onto the enamel twice daily. The percentage of surface hardness loss, integrated loss of subsurface hardness, calcium, phosphorus, and fluoride in enamel and biofilms were determined. In addition, alkali-soluble extracellular polysaccharide concentrations were analyzed in the biofilms. The irritation potential was evaluated using the hen's egg chorioallantoic membrane test through the vascular effect produced during 300-s of exposure. RESULTS: ETF was the most efficacious in preventing demineralization. It also showed the highest concentrations of calcium and phosphorus in the enamel and in the biofilm, as well as the lowest amount of extracellular polysaccharides in the biofilm. In the eggs, ETF produced light reddening, whereas CM led to hyperemia and hemorrhage. CONCLUSIONS: The addition of PPE to formulations containing TMP and F increased its anti-demineralizing property, and this formulation presented a lower irritation potential than the CM. CLINICAL RELEVANCE: ETF can be a promising alternative alcohol-free mouthwash in patients at high risk of caries.

'Green' silver nanoparticles combined with tyrosol as potential oral antimicrobial therapy.

OBJECTIVES: This study aimed to evaluate silver nanoparticles (AgNPs) obtained by a 'green' route associated or not to tyrosol (TYR) against Streptococcus mutans and Candida albicans in planktonic and biofilms states. METHODS: AgNPs were obtained by a 'green' route using pomegranate extract. The minimum inhibitory concentration (MIC) against S. mutans and C. albicans was determined for AgNPs and TYR combined and alone, and fractional inhibitory concentration index (FICI) was calculated. Single biofilms of C. albicans and S. mutans were cultivated for 24 h and then treated with drugs alone or in combination for 24 h. RESULTS: AgNPs and TYR were effective against C. albicans and S. mutans considering planktonic cells alone and combined. The MIC values obtained for C. albicans was 312.5 µg/mL (AgNPs) and 50 mM (TYR) and for S. mutans was 78.1 µg/mL (AgNPs) and 90 mM (TYR). The combination of these antimicrobial agents was also effective against both microorganisms: 2.44 µg/mL/0.08 mM (AgNPs/TYR) for C. albicans and 39.05 µg/mL /1.25 mM (AgNPs/TYR) for S. mutans. However, synergism was observed only for C. albicans (FICI 0.008). When biofilm was evaluated, a reduction of 4.62 log10 was observed for S. mutans biofilm cells treated with AgNPs (p < 0.05, Tukey test). However, the addition of TYR to AgNPs did not improve their action against biofilm cells (p > 0.05). AgNPs combined with TYR demonstrated a synergistic effect against C. albicans biofilms. CONCLUSIONS: These findings suggest the potential use of AgNPs with or without TYR against C. albicans and S. mutans, important oral pathogens. CLINICAL SIGNIFICANCE: AgNPs obtained by a 'green' route combined or not with TYR can be an alternative to develop several types of oral antimicrobial therapies and biomaterials.

Study of the activity of Punica granatum-mediated silver nanoparticles against Candida albicans and Candida glabrata, alone or in combination with azoles or polyenes.

The continuous emergence of Candida strains resistant to currently used antifungals demands the development of new alternatives that could reduce the burden of candidiasis. In this work silver nanoparticles synthesized using a green route are efficiently used, alone or in combination with fluconazole, amphotericin B or nystatine, to inhibit growth of C. albicans and C. glabrata oral clinical strains, including in strains showing resistance to fluconazole. A potent inhibitory effect over biofilm formation prompted by the two Candida species was also observed, including in mature biofilm cells. These results foster the use of phytotherapeutics as effective treatments in oral candidiasis.

Antimicrobial Potential and Cytotoxicity of Silver Nanoparticles Phytosynthesized by Pomegranate Peel Extract.

The phytosynthesis of metal nanoparticles is nowadays attracting the increased attention of researchers and is much needed given the worldwide matter related to environmental contamination. The antimicrobial activity of colloidal and spray formulation of silver nanoparticles (AgNPs) synthesized by pomegranate peel extract against Candida albicans and Staphylococcus aureus, and their cytotoxicity in mammalian cells were tested in the present study. Dry matter, pH, total phenolics, and ellagic acid in the extract were determined. Then, AgNPs were phytosynthesized and characterized by X-ray diffraction, electron transmission microscopy, dynamic light scattering, zeta potential, and Ag⁺ dosage. Spray formulations and respective chemical-AgNP controls were prepared and tested. The peel extract reduced more than 99% of Ag⁺, and produced nanoparticles with irregular forms and an 89-nm mean size. All AgNP presented antimicrobial activity, and the spray formulation of green-AgNP increased by 255 and 4 times the effectiveness against S. aureus and C. albicans, respectively. The cytotoxicity of colloidal and spray green-AgNP was expressively lower than the respective chemical controls. Pomegranate peel extract produced stable AgNP with antimicrobial action and low cytotoxicity, stimulating its use in the biomedical field.

Efeito da alteração na guia de desoclusão sobre a movimentação madibular, em indivíduos desdentados totais. Estudo cinesiográfico / Effect of the alteration on disocclusion guidance on madibular movements, in edentulous subjects. Kinesiographic study

Durante a construção de próteses totais, um padrão oclusal deve ser determinado para os movimentos laterais e protrusivo. Contudo, há controvérsias sobre qual tipo de oclusão, balanceada bilateral ou mutuamente protegida, deve ser aplicado. O propósito deste estudo foi avaliar os efeitos de uma mudança na guia lateral sobre os movimentos mandibulares em portadores de próteses totais. O instrumento cinesiográfico K6 I (Myotronics Research Inc., Seattle, WA, USA) foi usado para avaliar quatro pacientes desdentados que receberam, inicialmente próteses totais balanceadas bilateralmente. Padrões em compósito foram posicionados sobre os caninos das próteses maxilares, dando uma olusão mutuamente protegida, que foi mantida e avaliada por intervalos de tempo alternados, sem que o paciente soubesse dos propósitos das alterações. Os resultados não mostraram qualquer diferença significativa (alfa=5%) entre as situações experimentais, em relação à lateralidade, protrusão, abertura máxima e espaço funcional livre. Assim, foi possível concluir que as formas de oclusão excêntrica analisadas não exerceram um papel importante sobre o movimento mandibular em portadores de próteses totais, bem como na utilização das mesmas pelo paciente