Biosynthesis of silver nanoparticles in collagen gel improves their medical use in periodontitis treatment

Deciphering the Mechanisms and Biotechnological Implications of Nanoparticle Synthesis Through Microbial Consortia

Nanomaterial synthesis is a growing study area because of its extensive range of uses. Nanoparticles' high surface-to-volume ratio and rapid interaction with various particles make them appealing for diverse applications. Traditional physical and chemical methods for creating metal nanoparticles are becoming outdated because they involve complex manufacturing processes, high energy consumption, and the formation of harmful by-products that pose major dangers to human health and the environment. Therefore, there is an increasing need to find alternative, cost-effective, dependable, biocompatible, and environmentally acceptable ways of producing nanoparticles. The process of synthesizing nanoparticles using microbes has become highly intriguing because of their ability to create nanoparticles of varying sizes, shapes, and compositions, each with unique physicochemical properties. Microbes are commonly used in nanoparticle production because they are easy to work with, can use low-cost materials, such as agricultural waste, are cheap to scale up, and can adsorb and reduce metal ions into nanoparticles through metabolic activities. Biogenic synthesis of nanoparticles provides a clean, nontoxic, ecologically friendly, and sustainable method using renewable ingredients for reducing metals and stabilizing nanoparticles. Nanomaterials produced by bacteria can serve as an effective pollution control method due to their many functional groups that can effectively target contaminants for efficient bioremediation, aiding in environmental cleanup. At the end of the paper, we will discuss the obstacles that hinder the use of biosynthesized nanoparticles and microbial-based nanoparticles. The paper aims to explore the sustainability of microorganisms in the burgeoning field of green nanotechnology.

Addressing Antimicrobial Properties in Guided Tissue/Bone Regeneration Membrane: Enhancing Effectiveness in Periodontitis Treatment

Guided tissue regeneration (GTR) and guided bone regeneration (GBR) are the two surgical techniques generally used for periodontitis disease treatment. These techniques are based on a barrier membrane to direct the growth of new bone and gingival tissue at sites with insufficient volumes or dimensions of bone or gingiva for proper function, esthetics, or prosthetic restoration. Numerous studies have highlighted biocompatibility, space-creation, cell-blocking, bioactivity, and proper handling as essential characteristics of a membrane's performance. Given that bacterial infection is the primary cause of periodontitis, we strongly believe that addressing the antimicrobial properties of these membranes is of utmost importance. Indeed, the absence of effective inhibition of periodontal pathogens has been recognized as a primary factor contributing to the failure of GTR/GBR membranes. Therefore, we suggest considering antimicrobial properties as one of the key factors in the design of GTR/GBR membranes. Antibiotics are potent medications frequently administered systemically to combat microbes and mitigate bacterial infections. Nevertheless, the excessive use of antibiotics has resulted in a surge in bacterial resistance. To overcome this challenge, alternative antibacterial substances have been developed. In this review, we explore the utilization of alternative substances with antimicrobial properties for topical application in membranes. The use of antibacterial nanoparticles, phytochemical compounds, and antimicrobial peptides in this context was investigated. By carefully selecting and integrating antimicrobial agents into GTR/GBR membranes, we can significantly enhance their effectiveness in combating periodontitis. These antibacterial substances not only act as barriers against pathogenic bacteria but also promote the process of periodontal healing.

Recent advances in metal nanoparticles to treat periodontitis

The gradual deterioration of the supporting periodontal tissues caused by periodontitis, a chronic multifactorial inflammatory disease, is thought to be triggered by the colonization of dysbiotic plaque biofilms in a vulnerable host. One of the most prevalent dental conditions in the world, periodontitis is now the leading factor in adult tooth loss. When periodontitis does develop, it is treated by scraping the mineralized deposits and dental biofilm off the tooth surfaces. Numerous studies have shown that non-surgical treatment significantly improves clinical and microbiological indices in individuals with periodontitis. Although periodontal parameters have significantly improved, certain bacterial reservoirs often persist on root surfaces even after standard periodontal therapy. Periodontitis has been treated with local or systemic antibiotics as well as scaling and root planning. Since there aren't many brand-new antibiotics on the market, several researchers are currently concentrating on creating alternate methods of combating periodontal germs. There is a delay in a study on the subject of nanoparticle (NP) toxicity, which is especially concerned with mechanisms of action, while the area of nanomedicine develops. The most promising of them are metal NPs since they have potent antibacterial action. Metal NPs may be employed as efficient growth inhibitors in a variety of bacteria, making them useful for the treatment of periodontitis. In this way, the new metal NPs contributed significantly to the development of efficient anti-inflammatory and antibacterial platforms for the treatment of periodontitis. The current therapeutic effects of several metallic NPs on periodontitis are summarized in this study. This data might be used to develop NP-based therapeutic alternatives for the treatment of periodontal infections.

Advanced materials and technologies for oral diseases

Oral disease, as a class of diseases with very high morbidity, brings great physical and mental damage to people worldwide. The increasing burden and strain on individuals and society make oral diseases an urgent global health problem. Since the treatment of almost all oral diseases relies on materials, the rapid development of advanced materials and technologies has also promoted innovations in the treatment methods and strategies of oral diseases. In this review, we systematically summarized the application strategies in advanced materials and technologies for oral diseases according to the etiology of the diseases and the comparison of new and old materials. Finally, the challenges and directions of future development for advanced materials and technologies in the treatment of oral diseases were refined. This review will guide the fundamental research and clinical translation of oral diseases for practitioners of oral medicine.

Polymeric Dental Nanomaterials: Antimicrobial Action

This review aims to describe and critically analyze studies published over the past four years on the application of polymeric dental nanomaterials as antimicrobial materials in various fields of dentistry. Nanoparticles are promising antimicrobial additives to restoration materials. According to published data, composites based on silver nanoparticles, zinc(II), titanium(IV), magnesium(II), and copper(II) oxide nanoparticles, chitosan nanoparticles, calcium phosphate or fluoride nanoparticles, and nanodiamonds can be used in dental therapy and endodontics. Composites with nanoparticles of hydroxyapatite and bioactive glass proved to be of low efficiency for application in these fields. The materials applicable in orthodontics include nanodiamonds, silver nanoparticles, titanium(IV) and zinc(II) oxide nanoparticles, bioactive glass, and yttrium(III) fluoride nanoparticles. Composites of silver nanoparticles and zinc(II) oxide nanoparticles are used in periodontics, and nanodiamonds and silver, chitosan, and titanium(IV) oxide nanoparticles are employed in dental implantology and dental prosthetics. Composites based on titanium(IV) oxide can also be utilized in maxillofacial surgery to manufacture prostheses. Composites with copper(II) oxide nanoparticles and halloysite nanotubes are promising materials in the field of denture prosthetics. Composites with calcium(II) fluoride or phosphate nanoparticles can be used in therapeutic dentistry for tooth restoration.

Silver Nanoparticles as Chlorhexidine and Metronidazole Drug Delivery Platforms: Their Potential Use in Treating Periodontitis

Purpose

Materials and Methods

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Conclusion

Role of Biogenic Capping Agents in the Synthesis of Metallic Nanoparticles and Evaluation of Their Therapeutic Potential

The biomedical properties of nanoparticles have been the area of focus for contemporary science; however, there are issues concerning their long-term toxicities. Recent trends in nanoparticle fabrication and surface manipulation, the use of distinctive biogenic capping agents, have allowed the preparation of nontoxic, surface-functionalized, and monodispersed nanoparticles for medical applications. These capping agents act as stabilizers or binding molecules that prevent agglomeration and steric hindrance, alter the biological activity and surface chemistry, and stabilize the interaction of nanoparticles within the preparation medium. Explicit features of nanoparticles are majorly ascribed to the capping present on their surface. The present review article is an attempt to compile distinctive biological capping agents deployed in the synthesis of metal nanoparticles along with the medical applications of these capped nanoparticles. First, this innovative review highlights the various biogenic capping agents, including biomolecules and biological extracts of plants and microorganisms. Next, the therapeutic applications of capped nanoparticles and the effect of biomolecules on the efficiency of the nanoparticles have been expounded. Finally, challenges and future directions on the use of biological capping agents have been concluded. The goal of the present review article is to provide a comprehensive report to researchers who are looking for alternative biological capping agents for the green synthesis of important metallic nanoparticles.

Influence of the new formulation based on silver alginate microcapsules loaded with tannic acid on the microcirculation of the experimental periodontitis in rats

The microvascular changes caused by disorders of host immune response to oral microorganisms resulting in long-lasting inflammation of gums play a critical role in the periodontal lesion in the pathogenesis of chronic periodontitis. Current strategies of non-surgical periodontal therapy are aimed at the attainment of anti-inflammatory effects. We hypothesized that the usage of the microencapsulated form of anti-inflammatory substances with vasoactive effects could enhance the efficiency of the therapy by the prolonged release of active components. The prepared suspension of silver-alginate microcapsules loaded with tannic acid in the hydrogel was applied in vivo to the experimental model of periodontitis in rats induced by a ligature. The effect of this formulation was assessed by monitoring changes in local microcirculation performed by the Laser Doppler Flowmetry (1 and 24 h after application of hydrogel on intact gums and 21-days after the start of periodontitis' modeling). Application of the hydrogel containing multicomponent microcapsules to the affected area of gums allows correction of inflammatory microcirculatory disorders in model periodontitis. Immobilization of tannic acid into microcapsules allows increasing the correction of the following parameters: perfusion disorders, neurogenic tone of arterioles, myogenic tone of precapillary sphincters, as well as a venous outflow in the microvasculature of the gums. The hydrogel containing multicomponent microcapsules reduces the vascular inflammatory response in the model of periodontitis. Loading of silver-alginate microcapsules with tannic acid enhances the efficiency of microvascular disorders' correction in the model of periodontitis that suggests the prospects for application of this drug delivery system for non-surgical treatment of periodontitis.

In vitro and in vivo evaluation of a biomimetic scaffold embedding silver nanoparticles for improved treatment of oral lesions

BACKGROUND

New materials are currently designed for efficient treatment of oral tissue lesions by guided tissue regeneration. The aim of this study was to develop a multifunctional 3D hybrid biomaterial consisting of extracellular matrix components, collagen, chondroitin 4-sulfate and fibronectin, functionalised with silver nanoparticles, intended to improve periodontitis treatment protocols.

METHODS

Structural observations were performed by autometallography, scanning and transmission electron microscopy. In vitro tests of 3D constructs of embedded gingival fibroblasts within hybrid biomaterial were performed by MTS and Live/Dead assays. Genotoxicity was assessed by comet assay. In vivo experiments using chick embryo chorioallantoic membrane (CAM) assay analysed the degradation and nanoparticles release, but also angiogenesis, new tissue formation in 3D constructs and the regenerative potential of the hybrid material. Biological activity was investigated in experimental models of inflamed THP-1 macrophages and oral specific bacterial cultures.

RESULTS

Light micrographs showed distribution of silver nanoparticles on collagen fibrils. Scanning electron micrographs revealed a microstructure with interconnected pores, which favoured cell adhesion and infiltration. Cell viability and proliferation were significantly higher within the 3D hybrid biomaterial than in 2D culture conditions, while absence of the hybrid material's genotoxic effect was found. In vivo experiments showed that the hybrid material was colonised by cells and blood vessels, initiating synthesis of new extracellular matrix. Besides the known effect of chondroitin sulfate, incorporated silver nanoparticles increased the anti-inflammatory activity of the hybrid biomaterial. The silver nanoparticles maintained their antibacterial activity even after embedding in the polymeric scaffold and inhibited the growth of F. nucleatum and P. gingivalis.

CONCLUSION

The novel biomimetic scaffold functionalised with silver nanoparticles presented regenerative, anti-inflammatory and antimicrobial potential for oral cavity lesions repair.

Extracellular matrix biomimetic polymeric membranes enriched with silver nanoparticles for wound healing

Severe skin injuries, including burns, represent a real concern for the global health-care system and therefore, there is an increased interest in developing wound dressings, in order to stimulate and enhance skin tissue repair. The aim of this study was to design novel hybrid materials, biomimetic to skin extracellular matrix and enriched with silver nanoparticles (nAg), in order to provide both dermal tissue regeneration and antimicrobial activity. Two material variants (variant A and variant B) consisting of type I collagen (COL), chondroitin sulfate (CS) and k-elastin peptides (EL) enriched with positively-charged nAg, were conditioned as membranes. UV exposure ensured both sterilisation and cross-linking of the materials. Physico-chemical characterization of the hybrid biomaterials showed values of density and swelling degree higher than those of COL membrane, while the process of in vitro degradation followed a similar pattern. Infrared spectroscopy and X-ray diffraction indicated alterations of the characteristic structural features and crystallinity of COL after blending with CS and EL and nAg embedding. Scanning electron microscopy observations revealed different surface morphologies of the hybrid membranes, according to their composition. In vitro studies on L929 fibroblasts and HaCaT keratinocytes showed that both hybrid membranes exhibited good cytocompatibility and promoted higher cell proliferation compared to COL sample, as evaluated by MTT and Live/Dead assays. The presence of actin filaments highlighted by fluorescent labelling confirmed the fibroblast and keratinocyte adhesion onto the surface of hybrid membranes. Most importantly, both materials showed an increased wound healing ability in an in vitro scratch assay model, stimulating cell migration at 24 h post-seeding. In addition, good antimicrobial activity was recorded, especially against Gram-positive bacterial strain. Altogether, our findings recommend COL-CS-EL-nAg hybrid membranes as good candidates for wound healing acceleration and bioengineering of skin tissue.

Antifungal and Cytotoxic Evaluation of Photochemically Synthesized Heparin-Coated Gold and Silver Nanoparticles

Heparin-based silver nanoparticles (AgHep-NPs) and gold nanoparticles (AuHep-NPs) were produced by a photochemical method using silver nitrate and chloroauric acid as metal precursors and UV light at 254 nm. UV-Vis spectroscopy graphs showed absorption for AgHep-NPs and AuHep-NPs at 420 nm and 530 nm, respectively. TEM revealed a pseudospherical morphology and a small size, corresponding to 10-25 nm for AgHep-NPs and 1.5-7.5 nm for AuHep-NPs. Their antifungal activity against Candida albicans, Issatchenkia orientalis (Candida krusei), and Candida parapsilosis was assessed by the microdilution method. We show that AgHep-NPs were effective in decreasing fungus density, whereas AuHep-NPs were not. Additionally, the viability of human gingival fibroblasts was preserved by both nanoparticle types at a level above 80%, indicating a slight cytotoxicity. These results are potentially useful for applications of the described NPs mainly in dentistry and, to a lesser extent, in other biomedical areas.

Tailored Biomaterials for Therapeutic Strategies Applied in Periodontal Tissue Engineering

Several therapeutic strategies are currently in development for severe periodontitis and other associated chronic inflammatory diseases. Guided tissue regeneration of the periodontium is based on surgical implantation of natural or synthetic polymers conditioned as membranes, injectable biomaterials (hydrogels), or three-dimensional (3D) matrices. Combinations of biomaterials with bioactive factors represent the next generation of regenerative strategy. Cell delivery strategy based on scaffold-cell constructs showed potential in periodontitis treatment. Bioengineering of periodontal tissues using cell sheets and genetically modified stem cells is currently proposed to complete existing (pre)clinical procedures for periodontal regeneration. 3D structures can be built using computer-assisted manufacturing technologies to improve the implant architecture effect on new tissue formation. The aim of this review was to summarize the advantages and drawbacks of biomimetic composite matrices used as biomaterials for periodontal tissue engineering. Their conditioning as two-dimensional or 3D scaffolds using conventional or emerging technologies was also discussed. Further biotechnologies are required for developing novel products tailored to stimulate periodontal regeneration. Additional preclinical studies will be useful to closely investigate the mechanisms and identify specific markers involved in cell-implant interactions, envisaging further clinical tests. Future therapeutic protocols will be developed based on these novel procedures and techniques.