Silver nanoparticles associated with a polyphosphate and fluoride enhance the prevention of enamel demineralization and impact on dual-biofilm adhesion.

OBJECTIVES: The aim of this study were to produce a multifunctional nanocomposite combining silver nanoaparticles (Ag), sodium trimetaphosphate (TMP) and fluoride (F), to investigate its effect on dental enamel demineralization and on biofilms of Streptococcus mutans and Candida albicans. METHODS: Bovine enamel blocks were submitted to five pH cycles and treated 2x/day with 100 ppm F, 225 ppm F, 100 ppm F + 0.2%TMP or 100 ppm F + 0.2%TMP+10% Ag (100F/TMP/Ag). Next, surface hardness loss (%SH), integrated loss of subsurface hardness (ΔKHN), enamel fluoride (F) and calcium (Ca) concentration were determined. Biofilms from single and dual species of S. mutans and C. albicans were treated with 100F/TMP/Ag, Ag or chlorhexidine gluconate for 24 h. The antibiofilm effect was evaluated by colony-forming unit counting and Scanning Electron Microscopy. RESULTS: The nanocomposite reduced 43.0% of %SH and was similar with samples treated with 225F, 100F/TMP and 100/TMP/Ag. The attribute of F and/or TMP in reducing ΔKHN in 5-20 µm was not affected by the addiction of Ag (110F = 225F = 100F/TMP = 100F/TMP/Ag > Negative Control). Further, 100F/TMP/Ag strongly reduced viable cells of S. mutans in dual biofilms (∼5 log10cm2) and structurally affected the biofilms. CONCLUSION: The 100F/TMP/F promoted a protective effect against enamel demineralization and was able to significantly inhibit the growth of biofilms of S. mutans and C. albicans. CLINICAL SIGNIFICANCE: The focus on prevention and non-invasive dental treatment is the most effective and least costly way to improve the population's oral health conditions. We present a nanocomposite for a multiple approach in prevention of caries.

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.

Sodium trimetaphosphate and hexametaphosphate impregnated with silver nanoparticles: characteristics and antimicrobial efficacy.

This study aimed to synthesize and characterize materials containing silver nanoparticles (AgNP) with polyphosphates (sodium trimetaphosphate (TMP) or sodium hexametaphosphate (HMP), and evaluate their effect against Candida albicans and Streptococcus mutans. The minimum inhibitory concentration (MIC) was determined, which was followed by the quantification of the biofilm by counting colony-forming units (CFUs), the amount of metabolic activity, and the total biomass. The MICs revealed greater effectiveness of composites containing 10% Ag (TMP + Ag10% (T10) and HMP + Ag10% (H10)) against both microorganisms. It was observed that T10 and H10 reduced the formation of biofilms by 56-76% for C. albicans and by 52-94% for S. mutans for total biomass and metabolic activity. These composites promoted significant log reductions in the number of CFUs, between 0.45-1.43 log10 for C. albicans and 2.88-3.71 log10 for S. mutans (p < .001). These composites demonstrated significant antimicrobial activity, especially against S. mutans, and may be considered a potential alternative for new dental materials.

Multidisciplinary treatment of adult patients with Class III malocclusion / Tratamento multidisciplinar de paciente adulto com má oclusão de Classe III

This article describes the multidisciplinary treatment of an adult patient presenting with Angle Class III malocclusion, alteration of the mandibular position, vertical alveolar bone loss and absence of teeth in the lower posterior region. With advancing age the existence of occlusal interference due to loss of teeth or tooth structure is very common, resulting in periodontal problems due to occlusal trauma. The options for treatment of Class III malocclusion in adolescent and adult patients include compensatory orthodontic treatment in mild to moderate cases and orthognathic surgery for moderate to severe cases. The combination of various dental specialties enabled improvement in the social circumstances of the patient. This can be observed objectively by the final dental relationship and by the skeletal and tegumentary cephalometric comparison between the situation at the beginning and at the end of the treatment. The compensatory treatment performed permitted the successful correction of a Class III malocclusion in the clinical case presented.

Este trabalho descreve o tratamento multidisciplinar de um paciente adulto com má oclusão de Classe III de Angle, alteração postural da mandíbula, perda óssea alveolar vertical e ausência dentária na região póstero-inferior. Com o avanço da idade é muito comum a existência deinterferências oclusais devido à perda de dentes ou de estrutura dentária, resultando em problemas periodontais devidos ao trauma oclusal. As opções de tratamento da má oclusão de Classe III em adolescentes e pacientes adultos incluem tratamento ortodôntico compensatórios emcasos suaves a moderados e cirurgia ortognática para casos moderados a severos. O resultado clínico da interação de diferentes especialidadesodontológicas permitiu uma melhora do aspecto social da paciente, objetivamente pela relação dentária final e pela comparação cefalométricaesquelética e tegumentar entre o início e final de tratamento. O tratamento compensatório realizado possibilitou o sucesso na correção de umamá oclusão de Classe III do caso clínico apresentado.