Antimicrobial gel with silver vanadate and silver nanoparticles: antifungal and physicochemical evaluation.

Aim: To develop a ß-AgVO3 gel and evaluate its physicochemical stability and antifungal activity against Candida albicans. Materials & methods: The gel was prepared from the minimum inhibitory concentration (MIC) of ß-AgVO3. The physicochemical stability was evaluated by centrifugation, accelerated stability (AS), storage (St), pH, syringability, viscosity and spreadability tests and antifungal activity by the agar diffusion. Results: The MIC was 62.5 µg/ml. After centrifugation, AS and St gels showed physicochemical stability. Lower viscosity and higher spreadability were observed for the higher ß-AgVO3 concentration and the minimum force for extrusion was similar for all groups. Antifungal effect was observed only for the ß-AgVO3 gel with 20xMIC. Conclusion: The ß-AgVO3 gel showed physicochemical stability and antifungal activity.

We used silver and vanadium to make a gel that can kill fungi in the mouth. We looked at the color of the gel, it's smell and also checked how well it lasted. The gel turned yellow and had no smell and did not spoil for at least 2 months. When we tested the gel against a type of fungus, it worked as well as another medicine called chlorhexidine, which is sold in pharmacies. But when we compared it with another medicine called nystatin, our gel was not as effective in killing the fungus.

Structure-properties correlation of acrylic resins modified with silver vanadate and graphene.

This study aimed to incorporate ß-AgVO3 and rGO into self-curing (SC) and heat-curing (HC) acrylic resins and to evaluate their physicochemical, mechanical, and antimicrobial properties while correlating them with the characterized material structure. Acrylic resin samples were prepared at 0 % (control), 0.5 %, 1 %, and 3 % for both nanoparticles. The microstructural characterization was assessed by scanning electron microscopy (SEM) (n = 1) and energy dispersive X-ray spectroscopy (EDS) (n = 1). The physicochemical and mechanical tests included flexural strength (n = 10), Knoop hardness (n = 10), roughness (n = 10), wettability (n = 10), sorption (n = 10), solubility (n = 10), porosity (n = 10), and color evaluation (n = 10). The microbiological evaluation was performed by counting colony-forming units (CFU/mL) and cell viability (n = 8). The results showed that the ß-AgVO3 samples showed lower counts of Candida albicans, Pseudomonas aeruginosa, and Streptococcus mutans due to their promising physicochemical properties. The mechanical properties were maintained with the addition of ß-AgVO3. The rGO samples showed higher counts of microorganisms due to the increase in physicochemical properties. It can be concluded that the incorporation of ß-AgVO3 into acrylic resins could be an alternative to improve the antimicrobial efficacy and performance of the material.

Antimicrobial activity of cleansers on the cobalt-chromium surface of removable partial denture: a systematic review.

This study aimed to review systematically the literature about the antimicrobial action of evaluated cleansers on the Co-Cr alloy of RPD. The search was conducted in MEDLINE/PubMed, Scopus, Lilacs, Embase and Science Direct May, 2022. The review was performed based on PRISMA guidelines and recorded in Open Science Framework. Independent reviewers performed the search, selection, extraction, and analysis of the data. The risk of bias of the in vitro and clinical trials studies was analyzed by the Joanna Briggs Institute tool. A total of 187 articles were found and 9 were included. The cleansers that showed antimicrobial action were 2% and 5.25% sodium hypochlorite, 0.12% chlorhexidine and NitrAdine effervescent tablet. Polident, Corega Tabs effervescent tablets and 5 mg/mL chitosan solution showed intermediate effects. Propolis and green tea toothpaste were not effective. Three articles presented a high risk of bias and 6, low risk. The cleansers that showed the highest antimicrobial efficacy on Co-Cr alloy were 0.12% chlorhexidine digluconate and NitrAdine and can be safely used on RPD framework.

Influence of 3D-Printing Parameters and Characteristics of Complete Denture Bases on Evaluated Properties: A Scoping Review.

PURPOSE: To verify the parameters and characteristics evaluated in 3D-printed complete denture (CD) bases and how they influence CD properties. MATERIALS AND METHODS: This work was registered in Open Science Framework (osf.io/4um6v) and followed the PRISMA Extension for Scoping Reviews. A search of peer-reviewed articles published up to April 9, 2020, was performed on the PubMed, LILACS, Cochrane Library, and Science Direct databases. The review question based on the PCC (population, concept, and context) was: What printing parameters and characteristics of CD bases can influence their properties? RESULTS: The database search resulted in 1,945 articles, and the initial screening was carried out in 1,390 articles, 17 of which were selected for inclusion in this review. The present authors verified that cleaning the prosthesis with alcohol after printing followed by a postcuring cycle influences biocompatibility and residual monomers. The printing angle influences physicomechanical properties, microbial adhesion, and tissue adaptation. Accuracy is influenced by layer thickness and manufacturing technique, which also influences retention and tissue adaptation. The incorporation of antimicrobial agents influences physicomechanical properties and antimicrobial activity. The method of union between the denture base and teeth influences mechanical strength. CONCLUSIONS: Printed denture bases showed good adaptation to tissues and accuracy with 100-µm layer thickness, but the base must be cleaned in ethanol followed by postcuring for better biocompatibility. Nano- and microparticles can be added to provide antimicrobial activity and better resistance. The printing angle and mechanical properties must be better evaluated. Int J Prosthodont 2023;36:620-629.

Endodontic Sealers Modified with Silver Vanadate: Antibacterial, Compositional, and Setting Time Evaluation.

The incorporation of nanoparticles into endodontic sealers aims at increasing antimicrobial activity of the original material. Aim. The aim of this study is to incorporate the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3, at 2.5%, 5%, and 10%) into three endodontic sealers and evaluate the antibacterial activity of freshly sealers, surface topography and chemical composition, and setting time. Material and Methods. The AgVO3 was incorporated into AH Plus, Sealer 26, and Endomethasone N at concentrations 0%, 2.5%, 5%, and 10% (in mass). The antibacterial activity of freshly sealers was assessed by direct contact with Enterococcus faecalis and CFU/mL count (n=10), surface topography, and chemical composition were measured by SEM/EDS, and the setting time was measured by Gillmore needle (n=10). The Kruskal-Wallis and Dunn statistical tests were applied (α=0.05). Results. All groups of sealers evaluated inhibited E. faecalis (p>0.05). The incorporation of AgVO3 altered the atomic proportions between components of the endodontic sealers, and the percentage of silver (Ag) and vanadium (V) increased proportionally to the concentrations of AgVO3. Topography analysis showed differences in components distribution on the surface of the specimens. The sealers incorporated with AgVO3 of AH Plus presented a lower setting time than the control group (p<0.05). For Sealer 26 and Endomethasone N, the incorporation of AgVO3 increased the setting time in relation to control group (p<0.05). Conclusions. The modification of endodontic sealers by AgVO3 increased the atomic percentage of Ag and V proportionally to the concentration of the nanomaterial and changed the atomic percentage of the sealer components and setting times. It cannot be affirmed that the AgVO3 promote differences in the antimicrobial activity of freshly sealers, and further investigations of the antimicrobial activity of the set sealers should be carried out.

Influence of Adding Nanoparticles of Silver Vanadate on Antibacterial Effect and Physicochemical Properties of Endodontic Sealers.

Introduction: The aim of this study was adding the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3) (0, 2.5, 5, and 10%) to the endodontic sealers AH-Plus, Sealer 26 and Endomethasone N, and evaluate the antimicrobial activity, solubility and pH. Methods and Materials: The antimicrobial activity of freshly mixed sealers (n=10) and set sealers (n=9) against Enterococcus faecalis (E. faecalis) was evaluated by colony forming units per milliliter and epifluorescence microscopy. Solubility (n=9) and pH (n=10), 6 and 24 h and 7, 14, and 30 days were also evaluated. The Kruskal-Wallis and Dunn's post-test were applied for the antimicrobial activity of fresh sealers. ANOVA and Tukey's post-test was used for set sealers and solubility, and Friedman's two-way analysis of variance for pH (α=0.05). Results: The fresh sealers inhibited E. faecalis. Set Sealer 26 (5 and 10% AgVO3) and Endomethasone N (2.5, 5, and 10% AgVO3) presented higher activity then the corresponding controls. Modification with AgVO3 did not influence the solubility of AH Plus and Sealer 26, but Endomethasone N (5%) presented reduced solubility. The AH-Plus groups showed acidic pH, and Sealer 26, basic pH after 30 days. Endomethasone N (5 and 10% AgVO3) presented statistical difference compared to 0% (P<0.05). Conclusion: In this in vitro study all fresh sealers and set Sealer 26 (5 and 10%) and Endomethasone N (2.5, 5, and 10%) presented higher antimicrobial activity than controls. The modification with 5% and 10% AgVO3 decreased solubility and pH of Endomethasone N, but did not affect the other groups.

Effect of incorporation of a new antimicrobial nanomaterial on the physical-chemical properties of endodontic sealers.

OBJECTIVES: The objective of the study is to incorporate the nanostructured silver vanadate (AgVO3) decorated with silver nanoparticles at endodontic sealers AH Plus, Sealapex, Sealer 26, and Endofill, at concentrations of 2.5%, 5%, and 10%, and to evaluate physical-chemical properties. MATERIALS AND METHODS: The study was to evaluate the radiopacity using digital radiography (n = 5), the tooth color change in 48 incisors (n = 3) for 7, 30, 90, and 180 days in a spectrophotometer, and the topographic distribution in a confocal laser (n = 5). The radiopacity was analyzed by Kruskal-Wallis test and the permutation (α = 0.05) and the color and topographical distribution by descriptive statistical analysis. RESULTS: The AgVO3 had no effect on the radiopacity of Endofill and Sealapex (P > 0.05) and at 2.5% concentrations increased the radiopacity of Sealer 26 and AH Plus (P < 0.05). The Endofill 10% showed less color change, and the major changes were the modified groups in 180 days. The AgVO3 showed a circular topographic distribution in areas of the sealers. CONCLUSION: It was found that the addition of AgVO3 did not affect the radiopacity of Endofill and Sealapex however, increased the radipacity of Sealer 26 and AH Plus. For modified groups, the greatest color change was promoted after 180 days, except for Endofill with 10%. Topographic distribution of nanomaterial affected the color change of theevaluated sealers.

Análise da superfície de implantes odontológicos submetidos a ensaio de torção / Surface analysis of dental implants tested in torsion

Objetivo: Avaliar o comportamento mecânico de im-plantes odontológicos submetidos à torção manual, a fim de analisar o ponto de ruptura e determinar a região mais frágil e susceptível à deformação, por meio de mi-croscopia eletrônica de varredura, antes e após a reali-zação do ensaio de torção. Materiais e método: Foram selecionados quatro modelos de implantes da marca Co-nexão® (n=5): Master Screw, Porous, Conect AR e Conect Cônico. Foi utilizado um torquímetro digital para a apli-cação de torque e com um microscópio eletrônico de varredura avaliou-se a superfície dos implantes antes e após o ensaio de torção. Resultados: Os resultados foram obtidos pela análise estatística ANOVA (P < 0,05), segui-do do teste de Tukey (P < 0,05). Após a torção verificou--se que as quatro amostras de implantes apresentaram diferentes médias para a variável força máxima, porém, sem diferença estatística significante para os implantes Master Screw, Porous e Conect AR (p > 0,05), sendo ape-nas o implante Conect Cônico estatisticamente diferente (p < 0,05). Quanto às imagens obtidas a partir da análise ao MEV observou-se fratura do montador dos implantes Master Screw e Porous, ruptura dos implantes Conect AR, e espanamento das roscas internas dos Cônicos. Conclusão: Os modelos de implantes testados apresen-taram diferentes comportamentos mecânicos quando submetidos à aplicação de forças, com os Cônicos apre-sentando menor resistência ao ensaio de torção.