Persistent, antimicrobial coating with self-cleaning surface function derived from contra-stoichiometric surface segregation of polyethylene glycol-block-poly(N-isopropylacrylamide)

Background: Early childhood caries (ECC) is a common type of dental caries with an overall prevalence of 49.6% in India. Dentifrices- containing 1000-1500ppm concentration of fluorides and certain remineralizing agents are known to be effective in reversal of early enamel lesions and reduction of dental caries prevalence. However, in India, the mean fluoride content of dentifrices available for children is only 449.5 ± 26.1 ppm. Only very few toothpastes with the recommended concentration of fluoride is available in the Indian market, for children below the age of 6 years. Aims: To compare and evaluate the remineralization potential and antimicrobial efficacy of toothpaste with highest amount of fluoride, available in India for children below 6years of age, with non-fluoridated remineralizing children’s toothpaste. To assess the Total Soluble Fluoride (TSF) concentration of fluoridated toothpastes. Methodology: 95 extracted or naturally exfoliated human primary teeth were decoronated and sectioned mesiodistally. Specimens were demineralized and randomly divided into six groups (3 fluoridated and 3 non-fluoridated remineralising toothpaste groups): group 1: Omnident®- 917ppm, group 2: AquaFresh®™ little teeth- 1450ppm, group 3: Colgate kids®- 1000ppm, group 4: Enafix® (Ca. orthophosphate + Ca. Sucrose phosphate), group 5: Aclaim® (Nano HAP) and group 6: Shy-NM® (Novamin). The samples were placed in the demineralizing solution for 48h and subjected to Vickers hardness test (VHT) and SEM to obtain the baseline values. Then the samples were remineralized using the respective toothpastes and were subjected to SEM and VHT at 21days, 3months and 6months intervals. Antimicrobial activity of all the dentifrices was determined by agar well diffusion method and selective ion electrode analysis was used to evaluate the Total Fluoride (TF) and Total Soluble Fluoride (TSF) concentrations among the three fluoridated toothpastes. The data obtained were statistically analysed. Results: SEM images showed mineral deposition in all the groups obliterating the defects caused due to demineralization at various intervals. Remineralising agents showed significantly higher remineralisation especially SHY-NM when compared to Fluoridated toothpastes. However they did not show any antimicrobial efficacy. Fluoridated toothpastes showed antimicrobial efficacy against S. mutans and the highest antimicrobial efficacy was seen with Aquafresh followed by Omnident and Colgate Kids which was directly proportional to the TSF concentration of the toothpastes. Conclusions: Highest remineralisation of artificial enamel lesions was shown by non- fluoridated remineralising toothpaste, however, the fluoridated dentifrices displayed both antimicrobial and remineralising properties. The Total Soluble Fluoride (TSF) concentration of fluoride toothpastes were generally slightly less than the Total Fluoride (TF) concentration (TSF/F (%): 97%- AquaFresh®TM, 61.1%-Colgate kids® and 96.5% in Omnident®), which can be correlated to the dose-dependant antimicrobial efficacy as well as remineralisation of the fluoridated toothpastes. Keywords: remineralization potential, antimicrobial efficacy, toothpaste with highest amount of fluoride, dental caries.

Hospital acquired infections (HAIs) and the emergence of antibiotic resistant strains are major threats to human health. Copper is well known for its high antimicrobial efficacy, including the ability to kill superbugs and the notorious ESKAPE group of pathogens. We sought a material that maintains the antimicrobial efficacy of copper while minimizing the downsides – cost, appearance and metallic properties – that limit application. Here we describe a copper-glass ceramic powder as an additive for antimicrobial surfaces; its mechanism is based on the controlled release of copper (I) ions (Cu1+) from cuprite nanocrystals that form in situ in the water labile phase of the biphasic glass ceramic. Latex paints containing copper-glass ceramic powder exhibit ≥99.9% reduction in S. aureus, P. aeruginosa, K. aerogenes and E. Coli colony counts when evaluated by the US EPA test method for efficacy of copper-alloy surfaces as sanitizer, approaching that of benchmark metallic copper.

Background:Enterococcus faecalis is the most common and important microorganism found in infected root canals associated with persistent periapical periodontitis and failing endodontically treated tooth. Intracanal medicaments used after chemomechanical preparation of an infected root canal play a vital in eradication of this microorganism and pave the way for long-term success of endodontic therapy. Hence, the present in vitro study was conducted to assess the antimicrobial efficacy of calcium hydroxide (Ca(OH)2), triple antibiotic paste (metronidazole 400 mg + minocycline 100 mg + ciprofloxacin 500 mg), and 2% chlorhexidine (CHX) combined with 0.5% cetrimide on eradication of E. faecalis biofilm.Materials and Methods:Eighty dentin specimens were taken and infected extraorally with E. faecalis to induce microbial colonization. The specimens were then divided into four groups of twenty each based on medicaments used and further subdivided into two subgroups based on assessment of live cells done either immediately after the elimination of the medicament or after 24-h incubation in brain–heart infusion (BHI) medium: Group I specimens were treated with Ca(OH)2, Group II with triple antibiotic paste, Group III with 2% CHX combined with 0.5% cetrimide, and Group IV with saline (control) for 7 days at 37°C. Assessment of live cells was done using confocal microscope.Results:2% CHX combined with 0.5% cetrimide (Group III) and triple antibiotic paste (Group II) showed a statistically significant result with high antimicrobial efficacy and lower percentage of live cells as compared to Ca(OH)2 (Group I). The mean percentage of live cells in Group I immediately after elimination of medicaments was 64.7%, in Group II was 1.52%, in Group III was 1.49%, and in Group IV was 83.4%. After 24 h of incubation in BHI medium, 2% CHX combined with 0.5% cetrimide (Group III) showed a statistically significant (p < 0.05) result of 1.27% mean live cells as compared to 84.2% in Ca(OH)2 (Group I), 1.82% in triple antibiotic paste (Group II), and 94.2% in saline (Group IV control).Conclusion:2% CHX combined with 0.5% cetrimide exhibited maximum antimicrobial efficacy with least number of mean live cells followed by triple antibiotic paste as compared to Ca(OH)2. Based on these findings, 2% CHX combined with 0.5% cetrimide was most effective in eradicating E. faecalis from the extraorally infected dentine biofilm.

Glasses with high antimicrobial efficacy were developed in the Fe2O3-CuO-P2O5 ternary system to mitigate fomite-mediated transmission of infectious diseases in high-risk settings such as hospitals, daycares, and nursing homes. Binary CuO-P2O5 glasses were not durable enough for use as high touch point articles, so Fe2O3 was added to the compositions to increase the chemical durability. The amount of Cu leachate decreased by at least 3 orders of magnitude when Fe2O3 was increased from 0 to 13.1 mol%. At the highest Fe2O3 contents and corresponding highest durability, the glass was no longer able to pass a test of antimicrobial efficacy with < 3 log kill compared to > 5 log kill for all other compositions. Ab-initio molecular dynamics simulations showed increasing bridging oxygen species at the expense of non-bridging oxygen species with the increase in Fe2O3 content, showing that the glasses exhibited increased chemical durability because they were more interconnected and structurally bound. Experimental results with glasses at fixed CuO and decreasing Fe2O3 confirmed that Fe2O3 content (not CuO) controlled the Cu release rate and, thus, the antimicrobial efficacy of the glasses. The significance of the oxidation state of the leached Cu was overwhelmed by the importance of the amount of Cu leachate.

The purpose of the study was to assess the antimicrobial activity of an ultraviolet-C (UVC) device against microorganisms implicated in contact lens related adverse events. An UVC device with an emitting 4.5 mm diameter Light Emitting Diode (LED; 265 nm; 1.93 mJ/cm2) was used. Pseudomonas aeruginosa, Staphylococcus aureus, Fusarium solani, and Candida albicans agar plate lawns were exposed to the device beams for 15 and 30 s at 8 mm distance. Following the exposure, the diameter of the growth inhibition zone was recorded. Contact lenses made of Delfilicon-A, Senofilicon-A, Comfilicon-A, Balafilicon-A, Samfilicon-A and Omafilicon-A and a commercially available contact storage case was used. They were exposed to bacterial and fungal strains for 18 h at 37 °C and 25 °C respectively. After this, the samples were exposed to UVC for 30 s at 8 mm distance to determine the antimicrobial efficacy. Samples were then gently washed and plated on appropriate agar for enumeration of colonies. The UVC exposure reduced microbial growth by 100% in agar lawns, and significantly (p < 0.05) reduced microbial contamination to contact lenses and cases, ranging between 0.90 to 4.6 log. Very short UVC exposure has high antimicrobial efficacy against most of the predominant causative microorganisms implicated in contact lens related keratitis. UVC could be readily used as a broad-spectrum antimicrobial treatment for lens disinfection.

Periapical pathosis is considered as a persistent microbial infection throughout the treatment period of root canal procedures. Recently the prevalence of endodontic failures is huge and this primarily accounts for the periapical pathogens; mainly Enterococcus faecalis and Candida albicans. Thus, with the advent of newer materials; identification of the most appropriate sealing material with highest antimicrobial efficacy is essential for endodontic success. To evaluate and compare the antimicrobial efficacy of MTA Angelus, Biodentine and Theracal LC against Enterococcus faecalis and Candida albicans. An in-vitro study was conducted using three silicate-based cements; MTA Angelus, Biodentine and Theracal LC. Their antimicrobial efficacy was evaluated using Tube dilution method and their Minimum inhibitory concentration (MIC) and Bacterial counts (CFU’s) were assessed and compared. Statistical analysis was done using Paired t-test and ANOVA at 95% confidence interval (p value &amp;#60;0.05).The MIC was highest and CFU’s were lowest with Biodentine in comparison with other two materials.There were statistically significant differences noted between Biodentine and MTA angelus: Our study results conclude that Biodentine was found to be more anti-bacterial as compared to MTA angelus and theracal LC.

Self-assembly has been identified as an innovative strategy for improving the antimicrobial efficacy and bioavailability of short peptides. However, the detailed molecular information of short peptides linking to the self-assembly structures and antimicrobial activity remains to be more clearly understood. This work reported that the constitutional isomeric sequences of cationic peptides showed a significant impact on their antimicrobial activity. We investigated the self-assembly structures of two constitutional isomeric peptides Ac-RFSFSFR-NH2 and Ac-SFRFRFS-NH2, which contained the same serine, alkaline, and phenylalanine residues but in a different order. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) revealed that the constitutional isomers self-assembled into different morphologies in an aqueous solution. The sequence with alkaline residues located at both termini of the peptide favored the formation of β-sheet conformation and nanofibers, while irregular nanospheres were observed when positioning the alkaline residues at the center of the isomeric peptide. The ζ-potential measurements showed that the Ac-RFSFSFR-NH2 nanofibers had a net potential of +17.4 mV, whereas the apparent potential of Ac-SFRFRFS-NH2 nanospheres dropped steeply to +1.0 mV. These differences of the constitutional isomeric peptides were directly reflected in their antimicrobial activities. In comparison with the peptide Ac-SFRFRFS-NH2, the constitutional isomer Ac-RFSFSFR-NH2 exhibited much higher antimicrobial efficacy against Gram-positive Staphylococcus aureus and Bacillus subtilis and Gram-negative Escherichia coli and Pseudomonas aeruginosa. Moreover, several pairs of constitutional isomeric peptides with a similar sequence layout yielded the same outcome. These collective results not only highlight the importance of the isomeric sequence on the antimicrobial efficacy of short peptides but also increase further potential in optimizing the design of self-assembled nano-antimicrobial peptides (AMPs).

Various food products distributed throughout the cold chain can present a health risk for consumers due to the presence of psychrotolerant B. cereus group species that possess enterotoxin genes and antibiotic resistance. As these bacteria can grow at the low temperatures used in the food industry, this study evaluated the antimicrobial efficacy of acetic acid, sodium hypochlorite, and thermal treatments for inhibition of psychrotolerant strains and the effect that differences in activation temperature (30 °C and 10 °C) have on their efficacy. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and bacterial growth assay of acetic acid and thermal treatment showed an equal or higher antimicrobial efficacy in isolates activated at 10 °C than in those activated at 30 °C. In particular, psychrotolerant strains from the B. cereus group were completely eliminated with 0.25% acetic acid, regardless of the activation temperature. The possibility of tolerance was determined by observing responses in cells activated at 10 and 30 °C when exposed to different concentrations of sodium hypochlorite. Five isolates activated at 10 °C exhibited enhanced survivability in sodium hypochlorite compared to isolates activated at 30 °C, and these isolates were able to grow in sodium hypochlorite at concentrations of 250 ppm or higher. Although a significant difference in antimicrobial efficacy was observed for psychrotolerant B. cereus group strains depending on the activation temperature, acetic acid may be the most effective antimicrobial agent against psychrotolerant B. cereus species isolated from food products distributed in a cold chain.

Purpose:The aim of this in-vitro study was to investigate the antimicrobial efficacy of identical experimental toothpastes with different stannous sources.Materials and Methods:Streptococcus mutans biofilms were grown on protein-coated glass disks in static conditions for 24 h and thereafter exposed to toothpaste slurries or physiological saline (negative control; n = 15) for 30 s. Four experimental toothpastes were applied in this study, containing either stannous chloride (SnCl2; B: 3500 ppm Sn2+, and D: 3600 ppm Sn2+) or stannous fluoride (SnF2; C: 3500 ppm Sn2+, and E: 3600 ppm Sn2+). Marketed toothpaste meridol® (A: 3300 ppm SnF2) served as control. All five toothpastes contained amine fluoride (AmF). The biofilms were placed on agar surface and their metabolic activity was assessed by isothermal microcalorimetry over 96 h. The heat flow data was analysed for growth rate and lag time using grofit package in software R. Additionally, reduction of active biofilm compared to untreated control was calculated.Results:All toothpastes significantly prolong the lag time of treated biofilms in comparison to negative control (p < 0.05). Toothpastes containing SnF2 (C and E) prolonged the lag time statistically significantly compared to toothpastes containing SnCl2 (B and D) (p < 0.05). The maximum growth rate was statistically significantly reduced by all tested toothpastes compared to the untreated control group (p < 0.05). Toothpastes containing SnF2 (A, C and E) reached 59.9 ± 7.8, 61.9 ± 7.7, and 55.6 ± 7.0% reduction of active biofilm, respectively. Thus, they exhibit statistically significantly better results than toothpastes B (52.9 ± 9.9%) and D (44.7 ± 7.6%). Toothpaste D, which contains a slightly higher concentration of Sn2+, was the least effective in reducing active biofilm.Conclusion:The toothpastes containing SnF2 combined with AmF had the highest antimicrobial efficacy in this study.

Superhydrophobic Surfaces Have Great Application Value in the Fields of Self-Cleaning, Corrosion Resistance, Fluid Drag Reduction, Ice Resistance and the Like, While Superhydrophobic Surfaces with Transparency, Conductivity or Other Functions Have Larger Application Space. the Appearance of the Lotus Leaf Has a Self-Cleaning Function, and the Most Typical Example is the Lotus Leaf Surface Which is out of Silt But Not Imbrued. through the Research and Analysis of Superhydrophobic Phenomena in Nature, the Low Surface Energy Substances on Superhydrophobic Surfaces and the Micro-Nano Scale Hierarchical Structure Are Considered as the Two Decisive Factors for Forming Superhydrophobic. the Classical Theory of Surface Wettability Indicates That the Wettability of Liquid Depends on the Surface Energy and Surface Roughness. Various Methods Have Been Developed for the Preparation of Superhydrophobic Surfaces with Conducting Polymers. by Selecting Materials with Appropriate Surface Energy and Fine Control of Surface Structure, Various Surface Functionalization Can Be Realized.

Background: Nano-biomaterials have transformed traditional medicine and are now considered an essential part of modern medicine. The present systemic review aimed to highlight the scope of silver nanoparticles in periodontal and peri-implant wound healing with special emphasis on its antibacterial effects in the management of periodontal and peri-implant infection in in vitro and in vivo animal studies. Methods: A computer search of electronic databases, mainly PubMed, was conducted with a combination of keywords. The investigation was limited to studies discussing the effects of silver or silver nanoparticles in periodontal regeneration and periodontal/peri-implant healing and/or disease. Results: The search resulted in 1566 articles of potential interest. Twenty-one articles were included in the systematic review for analy- sis. Although with considerable methodological limitations, the in vitro and in vivo animal studies noted high antibacterial properties of silver nanoparticles without any toxic effects on the cellular structure. In vitro and in vivo small-animal studies have demonstrated the safety and antimicrobial efficacy of AgNPs in periodontal and peri-implant wound healing. However, the therapeutic potential of AgNPs in clinical situations has not been explored. Conclusion: There is a need to establish animal models that are closer in soft and hard tissue response to humans to verify the safety and efficacy of silver nanoparticles. Owing to the potential risk of antimicrobial resistance with the contemporary antibiotics, unconventional therapeutic regiments, like silver nanoparticles, that are safe and have high antimicrobial efficacy should be tried as an adjunct in the management of periodontal and peri-implant therapy. Cite this article as: Siddiqi A, Zafar S. Scope of silver nanoparticles in periodontal and peri-implant wound healing: A systematic review of translation research. Essent Dent. 2023;2(2):55-65.

BackgroundSutures colonized by bacteria represent a challenge in surgery due to their potential to cause surgical site infections. In order to reduce these type of infections antimicrobially coated surgical sutures are currently under development. In this study, we investigated the antimicrobial drug octenidine as a coating agent for surgical sutures. To achieve high antimicrobial efficacy and required biocompatibility for medical devices, we focused on optimizing octenidine coatings based on fatty acids. For this purpose, antimicrobial sutures were prepared with either octenidine-laurate or octenidine-palmitate at 11, 22, and 33 μg/cm drug concentration normalized per length of sutures. Octenidine containing sutures were compared to the commercial triclosan-coated suture Vicryl® Plus. The release of octenidine into aqueous solution was analyzed and long-term antimicrobial efficacy was assessed via agar diffusion tests using Staphylococcus aureus. For determining biocompatibility, cytotoxicity assays (WST-1) were performed using L-929 mouse fibroblasts.ResultsIn a 7 days elution experiment, octenidine-palmitate coated sutures demonstrated much slower drug release (11 μg/cm: 7 %; 22 μg/cm: 5 %; 33 μg/cm: 33 %) than octenidine-laurate sutures (11 μg/cm: 82 %; 22 μg/cm: 88 %; 33 μg/cm: 87 %). Furthermore sutures at 11 μg/cm drug content were associated with acceptable cytotoxicity according to ISO 10993–5 standard and showed, similar to Vicryl® Plus, relevant efficacy to inhibit surrounding bacterial growth for up to 9 days.ConclusionsOctenidine coated sutures with a concentration of 11 μg/cm revealed high antimicrobial efficacy and biocompatibility. Due to their delayed release, palmitate carriers should be preferred. Such coatings are candidates for clinical testing in regard to their safety and efficacy.

The major goal of endodontic treatment is to eliminate bacteria from the root canals and prevent re-infection. Enterococcus faecalis (E. faecalis) has been attributed to be the most common organism for the endodontic treatment failures. The choice of endodontic material that have high antimicrobial efficacy can help in decreasing/avoiding growth of micro-organisms and facilitate the success rate of treatment. The present study was designed with an aim to evaluate the antimicrobial efficacy of antibiotic coated gutta-percha cones on E. faecalis. The present study was an invitro experimental study, conducted at Department of Public Health Densitry and Department of Microbiology. Gutta-percha cones were coated with different medicaments like Zinc Oxide-Eugenol cement (ZOE i.e. Group A), ZOE plus Amoxicillin-Clavulanic acid combination (Group B), ZOE plus Amoxicillin (Group C), ZOE plus Ofloxacin-Ornidazole combination (Group D). Agar plates were inoculated with E. faecalis and antibiotic coated gutta-percha cones along with conventional gutta-percha cones (coated only with ZOE) were placed in those agar plates. After 24hours incubation; diameter of zone of inhibition around gutta-percha stick was considered to assess the antimicrobial activity. Results were statistically analysed with analysis of variance (ANOVA) followed by Tukey post-hoc test for group-wise comparisons. Mean diameter of zone of inhibition (in mm) obtained for Group A, Group B, Group C and Group D were 5±0.03, 26.6±0.05, 21.5±0.04 and 15.8±0.03 respectively. The difference in values of different antibiotics was statistically significant. The p-value < 0.001 was considered statistically significant. Group B was most effective against E.faecalis compared to other combinations used which increase the success rate of endodontic treatment as compared to conventional gutta-percha cones.

Annotation. A high risk of infections in surgery is associated with microbial contamination with opportunistic microorganisms Staphylococcus aureus. Objective: to study the antimicrobial and analgesic effect of decamethoxine combined with lidocaine applied locally to the model of a postoperative infectious wound. Fifty-two male rats weighing 250-300 grams were randomly divided into four groups. We modeled surgical wounds in the interscapular area, and then injected a suspension culture of S. aureus 47 (dose 108 CFU/ml) into the wounds. On the 2nd, 3rd, 7th and 10th day of the experiment, the wounds contaminated with staphylococcal culture were treated with 3 ml doses of the tested drugs: 0,9% saline in the control group (group A, n=13), 0,02% decamethoxine antiseptic (DCM) (group B, n=13), 10% lidocaine (group C, n=13) and their combination in the 1:1 ratio (group D, n=13). On days 3, 7 and 10, the wound area in each group was determined using contour planimetry by the L.N. Popova method and the average area (M±m) and the percentage of reduction in wound area from the initial size were calculated. The antimicrobial efficacy of the antiseptic and anesthetic was evaluated on days 3, 5, 7 and 10 using a standard microbiological study of the number of microorganisms in the wounds, the numerical values of which were expressed as the decimal logarithm of colony-forming units per ml (lg CFU / ml). To study the analgesic activity of DCM and 10% lidocaine in animals, the minimum threshold of pain sensitivity in the wound was determined using calibrated Von Frey monofilaments (VFMs). Statistical processing was performed using standard biometric methods. Differences at p&lt;0.05 were considered significant. Results: As a result of microbiological examination of the wound surface, it was found that the number of S. aureus on the wound surface significantly decreased on the 5th day when using decamethoxine alone and in combination with lidocaine 10%. The use of antiseptic and its combination with lidocaine on the 10th day revealed almost complete eradication of S. aureus on the wound surface compared to the control group (p&lt;0.01). When applying the combined antiseptic with lidocaine, it was found that the threshold of pain sensitivity increased by 12.2 times, which was practically no different from that of lidocaine monotherapy (11.9%). It was found that the healing and wound epithelization rate was the highest in group D (71.12% of the baseline). So, the combination of antiseptic with lidocaine 10% in the treatment of wounds has a high antimicrobial efficacy with a pronounced anesthetic effect. Thus, it opens the prospect of combined local use of antiseptic and anesthetic in the treatment of wounds.

Bacteriophages (phages), highly prevalent in aquatic and terrestrial environments, have emerged as novel antimicrobial agents in food and agricultural systems. Owing to their efficient and unique infection mechanism, phages offer an alternative to antibiotic therapy as they specifically target their host bacteria without causing antibiotic resistance. However, the real-world applications of phages as antimicrobials are still limited due to their low survivability under harsh conditions and reduced antimicrobial efficacy. There is an unmet need to understand the challenges of using phages in food and agricultural systems and potential strategies to enhance their stability and delivery. This review overviews the challenges of using phages, including acidic conditions, improper temperatures, UV-light irradiation, desiccation, and inefficient delivery. It also summarizes novel strategies such as encapsulation, embedding, and immobilization, which enable improved viability and enhanced delivery. The protein capsid and nucleic acid components of phages are delicate and sensitive to physicochemical stresses. Incorporating phages into biocompatible materials can provide a physical barrier for improving phage stability and enhancing phage delivery, resulting in a high antimicrobial efficacy. In conclusion, the development of phage delivery systems can significantly overcome the challenges associated with phage treatments and reduce the risk of foodborne diseases in the industry.