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The interest in the use of green-mediated synthesis of nanoparticles (NPs) is shown to have increased due to their biocompatibility and reduction of overall production costs. The current study aimed to evaluate a novel nanocomposite (NC) prepared by using a combination of zinc oxide, silver and chitosan with lemon extract as a cross-linking agent and assessed its antimicrobial effectiveness against Enterococcus faecalis (E. faecalis). The NPs and NC were prepared individually using a modification of previously established methods. Ananalys is of the physiochemical properties of the NC was conducted using ultraviolet-visible spectroscopy (UV-Vis) (Shimadzu Corporation, Kyoto, Japan). and transmission electron microscopy (TEM) imaging(HR-TEM; JEOL Ltd., Akishima-shi, Japan. The microbial reduction with this novel NC was evaluated by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using a tube assay analytic technique. A time-kill assay analysis was conducted to evaluate the kinetic potential against E. faecalis at different time intervals. The novel NC showed a homogenous nanoparticle size under TEM imaging and under UV-Vis established an absorption range of 350–420 nm making it similar to its individual counterparts. The MIC and MIB were measured at 62.5 ± 20 mg/L (p < 0.05) and 250 ± 72 mg/L (p < 0.05), respectively. A time-kill assay analysis for the NC showed 5 h was required to eradicate E. faecalis. Based on the achieved results, it was seen that the novel NC using a combination of silver, zinc oxide and chitosan showed improved antimicrobial action against E. faecalis compared with its individual components under laboratory conditions. A complete eradication of 108 log units of E. faecalis at 250 mg/L occurred after a total of 5 h. These preliminary results establish the use of lemon extract-mediated silver, zinc and chitosan-based NC had an antibacterial effectiveness against E. faecalis similar to the individual counterparts used for its production under laboratory conditions. [ABSTRACT FROM AUTHOR]

This study aims to compare the hardness, sorption and solubility of commercially available tissue conditioner [TC] modified with chitosan [CS] and synthesized chitosan oligosaccharide [COS] in antifungal concentration. COS was synthesized by acid hydrolysis and characterized by FTIR and XRD. Experimental materials were formulated by incorporating each per gram of TC powder with effective antifungal concentration of chitosan 1.02 mg (Group 1: TC-CS) and 0.51 mg COS (Group 2: TC-COS). A commercially available TC was used as control (Group 0: CTC). Shore A hardness test was performed according to ASTM D 2240-05 (2010) standards on samples stored in dry environment, distilled water (DW) and artificial saliva (AS) at 37 °C (n = 5 per group). Percent weight changes (n = 5 per group) after storage in DW and AS was used to record sorption and solubility. One-way Anova with post hoc Tukey's test was applied. FTIR and XRD confirmed low molecular weight and amorphous nature of COS. Experimental groups had higher Shore A hardness values; however, these changes were not significant. Greatest variations in durometer values (p ≤ 0.05) were observed during the first 24 h. Experimental groups had higher (p ≤ 0.05) percentage sorption and solubility. Samples stored in DW had significantly higher (p = 0.019) sorption, whereas material had higher (p = 0.005) solubility in AS. Mean solubility values in both immersion mediums was highest for Group 2, followed by group 1 and group 0. In addition, significant (p ≤ 0.05) increase in solubility upon aging was noted for each material. Experimental tissue conditioner had higher hardness, sorption and solubility. However, these changes are not substantial to interfere with their tissue healing property. Therefore, these materials may be considered and explored further as potential antimicrobial drug delivery agent for denture stomatitis patients. [ABSTRACT FROM AUTHOR]

A vital feature of conservative dentistry is the adhesion of the restorative material to the tooth structure for restoration of the tooth substance lost due to dental decay, trauma, or dental imperfections. In a perfect world, a restorative material should generate a lasting adhesion by bonding the restoration with tooth tissues. The ingress of micro-organisms, oral fluids, molecules, and ions through microscopic spaces due to faulty adhesion between restoration and tooth structure is known as microleakage. This study is focuses on the evaluation of adhesive failures between the restorative materials. In the past, studies have focused more on the bonding potential of a restorative material with the tooth surface. Therefore, there is need to carry out a study that compares the microleakage between resin-based restorative materials in a sandwich manner with and without the intermediate bonding layer after immersion in 2% methylene blue dye at different time intervals. The restorative materials used were composite Ceram X Mono plus (DENTSPLY) and Z350 (3M ESPE), Vitremer resin modified glass ionomer cement (RMGIC) (3M ESPE), smart dentine replacement SDR (3M ESPE), Bond NT (DENTSPLY), and Universal Bond (3M ESPE). A light emitting diode (LED) was used to cure the specimens. Artificial saliva was used as a storage medium for the specimens. Thermocycling of specimens was carried out at 500 cycles/30 s and 1000 cycles/30 s. The world health organization (WHO) grading tool for microleakage was used to analyze fluid ingress in the specimens through disclosing by 2% methylene blue dye. The statistical analysis was carried out with one-way analysis of variance (ANOVA) and Tukey post hoc test, keeping the level of significance at p ≤ 0.05. In Grade 0 = 85 samples, Grade 1 = 10 samples, Grade 2 = 7 samples, Grade 3 = 16 samples, and in Grade 4 = 2 samples were identified. This study describes that no microleakage was observed in SDR and resin composite groups as compared to Vitremer and resin composite groups. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate if commonly used endodontic irrigants such as 3% sodium hypochlorite (NaOCl, Prime Dental, Thane, India), 2% chlorhexidine (CHX, Sigma-Aldrich Co., St. Louis, MO, USA), and 17% ethylenediaminetetraacetic acid (EDTA, Meta-Biomed Co. Ltd., Cheongju-si, South Korea) influenced the setting time and metal composition of different base endodontic sealers on exposure. AH Plus (Dentsply De Trey GmbH, Konstanz, Germany), Sealapex (SybronEndo, Orange, CA, USA), mineral trioxide aggregate (MTA) Fillapex (Angelus Soluções Odontológicas, Londrina, Brazil), and Tubli-Seal (Kerr Dental, Orange, CA, USA) were selected as the different base representatives of endodontic sealers. These sealers were exposed to 3% NaOCl, 2% CHX, and 17% EDTA, and the individual setting time of the sealers was analyzed. The samples were analyzed for heavy metal elements such as chromium (Cr), nickel (Ni), cobalt (Co), cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), and beryllium (Be) by using inductively coupled plasma mass spectrometry (ICP-MS) analysis. For statistical analysis, one-way ANOVA and post hoc Tukey's tests were used. All selected sealers showed variation in setting time post-exposure to different irrigants. MTA Fillapex had the shortest mean setting time (215.7 min, post-exposure at 187.3 min) (p < 0.05). Mean setting time was also affected for AH Plus (479.6 min, post-exposure at 423.9 min) (p < 0.05) and Tubli-Seal (514.7 min, post-exposure at 465.2 min) (p < 0.05). Sealapex showed the maximum reduction of setting time (864.8 min, post-exposure at 673.4 min) (p < 0.05). All tested sealers showed heavy metals (Cr, Ni, Co, Cd, As, Hg, and Pb) in their composition, and the quantities were influenced by interaction with different irrigants. The heavy metal Be was not seen in any of the samples. Sealapex showed the longest setting time in comparison to other test sealers. Heavy metals were most present in Sealapex, followed by AH Plus, Tubli-Seal, and MTA Fillapex. MTA Fillapex was seen to have the shortest setting time, and heavy metal composition was least affected on interaction with different commonly used endodontic irrigants. Further, this study provides significant insight into the influence of different endodontic irrigants on interaction with different base endodontic sealers, which has not been reported previously, and future studies should emphasize endodontic irrigant-sealer interactions and their possible effects in the long run. [ABSTRACT FROM AUTHOR]

The oral cavity is an intricate environment subjected to various chemical, physical, and thermal injuries. The effectiveness of the local and systemically administered drugs is limited mainly due to their toxicities and poor oral bioavailability that leads to the limited effectiveness of the drugs in the target tissues. To address these issues, nanoparticle drug delivery systems based on metals, liposomes, polymeric particles, and core shells have been developed in recent years. Nano drug delivery systems have applications in the treatment of patients suffering from temporomandibular joint disorders such as preventing degeneration of cartilage in patients suffering from rheumatoid arthritis and osteoarthritis and alleviating the pain along with it. The antibacterial dental applications of nano-drug delivery systems such as silver and copper-based nanoparticles include these agents used to arrest dental caries, multiple steps in root canal treatment, and patients suffering from periodontitis. Nanoparticles have been used in adjunct with antifungals to treat oral fungal infections such as candida albicans in denture wearers. Acyclovir being the most commonly used antiviral has been used in combination with nanoparticles against an array of viral infections such as the herpes simplex virus. Nanoparticles based combination agents offer more favorable drug release in a controlled manner along with efficient delivery at the site of action. This review presents an updated overview of the recently developed nanoparticles delivery systems for the management of temporomandibular joint disorders along with the treatment of different oral infections. [ABSTRACT FROM AUTHOR]

Electrospinning technology, which was previously known as a scientific interdisciplinary research approach, is now ready to move towards a practice-based interdisciplinary approach in a variety of fields, progressively. Electrospun nanofiber-applied products are made directly from a nonwoven fabric-based membranes prepared from polymeric liquids involving the application of sufficiently high voltages during electrospinning. Today, electrospun nanofiber-based materials are of remarkable interest across multiple fields of applications, such as in electronics, sensors, functional garments, sound proofing, filters, wound dressing and scaffolds. This article presents such a review for summarizing the current progress on the manufacturing scalability of electrospun nanofibers and the commercialization of electrospun nanofiber products by dedicated companies globally. Despite the clear potential and limitless possibilities for electrospun nanofiber applications, the uptake of electrospinning by the industry is still limited due to the challenges in the manufacturing and turning of electrospun nanofibers into physical products. The recent developments in the field of electrospinning, such as the prominent nonwoven technology, personal views and the potential path forward for the growth of commercially applied products based on electrospun nanofibers, are also highlighted. [ABSTRACT FROM AUTHOR]

The lack of aesthetic properties of electrospun nanofibres in terms of colour appearance is the drive in this preliminary study. This research is conducted to study the dyeing behaviour and colorimetric properties of electrospun nanofibres blended with Remazol Yellow FG reactive dye using dope-dyeing method via electrospinning process. This paper reports the colorimetric properties of dyed poly vinyl alcohol (PVA) nanofibres within the range of 2.5 wt.% to 12.5 wt.% dye content. The electrospinning parameters were fixed at the electrospinning distance of 10 cm, constant feed rate of 0.5 mL/h and applied voltage of 15 kV. The resulting impregnated dye of 10 wt.% exhibits acceptable colour difference of dyed PVA nanofibres, with a mean fibre diameter of 177.1 ± 11.5 nm. The SEM micrographs show the effect of dye content on morphology and fibre diameter upon the increment of dye used. Further increase of dye content adversely affects the jet stability during the electrospinning, resulting in macroscopic dropping phenomenon. The presence of all prominent peaks of Remazol dye in the PVA nanofibers was supported with FTIR analysis. The addition of dye into the nanofibres has resulted in the enhancement of thermal stability of the PVA as demonstrated by TGA analysis. [ABSTRACT FROM AUTHOR]

Although numerous studies have demonstrated the benefits of incorporating filler particles into maxillofacial silicone elastomer (MFPSE), a review of the types, concentrations and effectiveness of the particles themselves was lacking. The purpose of this systematic review and meta-analysis was to review the effect of different types of filler particles on the mechanical properties of MFPSE. The properties in question were (1) tensile strength, (2) tear strength, (3) hardness, and (4) elongation at break. The findings of this study can assist operators, technicians and clinicians in making relevant decisions regarding which type of fillers to incorporate based on their needs. The systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 26 original articles from 1970 to 2019 were selected from the databases, based on predefined eligibility criteria by two reviewers. The meta-analyses of nine papers were carried out by extracting data from the systematic review based on scoring criteria and processed using Cochrane Review Manager 5.3. Overall, there were significant differences favoring filler particles when incorporated into MFPSE. Nano fillers (69.23% of all studies) demonstrated superior comparative outcomes for tensile strength (P < 0.0001), tear strength (P < 0.00001), hardness (P < 0.00001) and elongation at break (P < 0.00001) when compared to micro fillers (30.76% of all studies). Micro fillers demonstrated inconsistent outcomes in mechanical properties, and meta-analysis of elongation at break argued against (P < 0.01) their use. Current findings suggest that 1.5% ZrSiO4, 3% SiO2, 1.5% Y2O3, 2–6% TiO2, 2–2.5% ZnO, 2–2.5% CeO2, 0.5% TiSiO4 and 1% Ag-Zn Zeolite can be used to reinforce MFPSE, and help the materials better withstand mechanical degradation. [ABSTRACT FROM AUTHOR]