Graphene-Based Nanomaterials for Dental Applications: Principles, Current Advances, and Future Outlook

Dentistry Insights: Single-Walled and Multi-Walled Carbon Nanotubes, Carbon Dots, and the Rise of Hybrid Materials

We are committed to writing this narrative review given that carbon-based nanomaterials are revolutionizing dental medicine. Since the groundbreaking discovery of carbon nanotubes in 1991, their dental applications have skyrocketed. The numbers speak for themselves: in 2024, the global carbon nanotubes market hit USD 1.3 billion and is set to double to USD 2.6 billion by 2029. Over the past few decades, various forms of carbon nanomaterials have been integrated into dental practices, elevating the quality and effectiveness of dental treatments. They represent a transformative advancement in dentistry, offering numerous benefits such as augmented mechanical properties, antimicrobial activity, and potential for regenerative applications. Both carbon nanotubes (CNTs) and carbon dots (CDs) are derived from carbon and integral to nanotechnology, showcasing the versatility of carbon nanostructures and delivering cutting-edge solutions across diverse domains, such as electronics, materials science, and biomedicine. CNTs are ambitiously examined for their capability to reinforce dental materials, develop biosensors for detecting oral diseases, and even deliver therapeutic agents directly to affected tissues. This review synthesizes their current applications, underscores their interdisciplinary value in bridging nanotechnology and dentistry, identifies key barriers to clinical adoption, and discusses hybrid strategies warranting further research to advance implementation.

Graphene and its modifications for enhanced adhesion in dental restoratives: a molecular docking and dynamics study

Graphene has attracted significant attention in dentistry due to its structural and adhesive properties, enhancing the mechanical performance of dental composites. This study investigates the behavior and interaction of monomers and graphene-based adhesives using molecular docking and molecular dynamics (MD) simulations. Binding energies and interactions between monomers and graphene derivatives were assessed using molecular docking, while MD simulations with the Forcite module and COMPASS II force field provided insights into the mechanical properties of the composites. The simulations involved energy minimization, NVT/NPT ensembles, and equilibration for 50 ns. The binding energies of the monomer-graphene complexes ranged from - 16.27 to -18.55 kcal/mol, with the Bis-GMA-Graphene Quantum Dot complex showing the most stable interaction. Mechanical properties such as Young's modulus, shear modulus, and flexural strength were calculated for selected complexes: Bis-GMA-Graphene Quantum Dot (14.74 GPa, 9.32 GPa, 120.51 MPa), EBPADMA-Graphene Quantum Dot (14.28 GPa, 9.13 GPa, 118.22 MPa), HEMA-Nitrogen-doped Graphene (9.85 GPa, 6.86 GPa, 95.7 MPa), TEGDMA-Graphene Oxide (11.96 GPa, 8.12 GPa, 110.23 MPa), and UDMA-CCOOH Functionalized Graphene (13.82 GPa, 8.43 GPa, 115.4 MPa). The Bis-GMA-Graphene Quantum Dot complex showed the highest stability with 20 hydrogen bonds. These results highlight graphene quantum dots and functionalized graphene derivatives as promising candidates for high-performance dental composites, offering strong adhesive properties and improved mechanical strength. Future research may focus on further optimizing these interactions and exploring additional graphene modifications.

Unlocking tiny titans: 360 view of the quantum dots nanotechnology for dental applications

Quantum dots (QDs) nanotechnology has gained significant attention in dentistry due to its unique properties, such as fluorescence, antimicrobial activity, and drug delivery potential. This review aims to identify the dental applications most actively incorporating QD technology and to examine the distinctive properties of QDs within Dentistry. Employing the Arksey and O'Malley five-stage framework, a systematic search was conducted across PubMed, EMBASE, and Scopus databases for English-language publications on QDs in dentistry. Scientific contributions were evaluated by analyzing publication volume, research trends, patents, and key areas of investigation. Of the 1,034 studies initially identified, 71 were fully screened, with 22 meeting the criteria for data extraction. Results showed that antimicrobial properties and bone regeneration are the primary focus areas for QDs in dental materials. Stock solutions and resin composites are the most common materials developed, with the studies primarily targeting ofenhancing antimicrobial capabilities and osteogenesis enhancement. Over the last decade, QDs have demonstrated potential in enhancing drug delivery, antimicrobial efficacy, and optical performance in dental materials. Despite their growing prominence, the clinical translation of QD-based technologies remains limited due to a lack of long-term studies.

A Comprehensive Narrative Review of Nanomaterial Applications in Restorative Dentistry: Reinforcement and Therapeutic Applications (Part II)

Nanotechnology has been widely introduced into many areas of dentistry, including restorative dentistry, where it has contributed greatly to the improvement of restorative materials and procedures. This review was conceived with the aim of exploring the various applications of nanotechnology in restorative dentistry. The review consists of two parts. The first part addressed applications for remineralization inhibition and remineralization. This current review is the second part aimed at focusing on the reinforcement of restorative materials and other therapeutic applications of nanomaterials. Among the nanoparticles that are used to reinforce restorative materials are carbon, zirconia, hydroxyapatite, titanium dioxide, alumina, and gold nanoparticles. Furthermore, other promising applications of nanotechnology are for hypersensitivity management, protective varnish, whitening effect, drug delivery, and nanorobotics, which includes performing major tooth repairs and conducting dentition renaturalization procedures. These applications highlight the potential of nanoparticles in restorative dentistry; however, there are still certain limitations that need to be handled.

Advances in macro-bioactive materials enhancing dentin bonding

The long-term stability of dentin bonding is equally crucial for minimally invasive aesthetic restoration. Although the dentin bonding meets clinical standards at the initial stage, its long-term efficacy remains suboptimal owing to the impact of physiological factors. Herein, we present a comprehensive analysis of macro-bioactive materials, including nanomaterials and polymer materials, to improve the longevity of dentin bonding and extend the lifespan of adhesive prosthetics through various mechanisms to achieve sustained and stable dentin bonding effects over an extended period. On the one hand, the macro-bioactive materials directly inhibit the enzymatic activity of matrix metalloproteinases (MMPs) or impede the acidogenic abilities of cariogenic microorganisms, thereby enhancing the local pH within the oral cavity. On the other hand, they indirectly prevent the activation of MMPs, thereby safeguarding the structural integrity of the resin-dentin bonding interface and efficiently improve its long-term stability. Moreover, these macro-bioactive materials establish cross-links with collagen fibers, promoting bionic remineralization and protecting the exposed collagen fibers within the hybrid layer from degradation. These processes ultimately enhance the mechanical properties of the resin-dentin bonding interface and efficiently improve its long-term stability.

Effect of graphene oxide on the biaxial flexural strength and translucency of ultrathin monolithic zirconia

PURPOSE

The purpose of this study was to investigate the influence of graphene oxide (GO) and hydrothermal aging on the biaxial flexural strength (BFS) and translucency (TP) of ultrathin monolithic zirconia with different yttria concentrations.

METHODS

Disc shaped specimens (n = 120) were milled using zirconia blocks (YZ-HT [HT], YZ-ST [ST], and YZ-XT [XT]) with a diameter of 15.0 mm and a thickness of 0.5 mm. Half of the specimens were immersed in 0.2 wt% GO-water dispersion (HTG, STG, and XTG) and subjected to hydrothermal aging for 10 h. The TP was measured using a reflection spectrophotometer and BFS was tested in a universal testing machine. Data were statistically analyzed with 2-way analysis of variance followed by post-hoc comparisons (α = 0.05).

RESULTS

The lowest mean TP was found in the group of STG aged for 10 h. Hydrothermal aging significantly decreased the TP values in the groups of HTG, STG, and XTG (P < 0.05). Significantly higher TP values were obtained in the groups of XT. Immersion in 0.2 wt% GO-water dispersion significantly improved the BFS values of STG, and XTG for the control and aged groups.

CONCLUSIONS

GO leads to decreased translucency while improving BFS for highly translucent zirconia ceramics.

Synergistic effects of reduced graphene oxide on the antibacterial activity of calcium hydroxide-based intracanal medicaments containing different vehicles

PURPOSE

This study investigated the synergistic effects of reduced graphene oxide (RGO) on the antibacterial activity of three calcium hydroxide-based intracanal medicaments with different vehicles.

METHODS

Multispecies biofilms were cultured in a bovine root canal model. Intracanal medicaments containing nonaqueous vehicles, including N-methyl-2-pyrrolidone (NMP; CleaniCal), propylene glycol (PG; UltraCal XS), and polyethylene glycol (PEG; Calcipex II), were placed in the model. The synergistic effects of RGO were evaluated by analyzing colony-forming units, extracellular deoxyribonucleic acid (eDNA) levels, and findings from confocal laser-scanning microscopy (CLSM) and scanning electron microscopy. To evaluate the cytotoxicity of each vehicle, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed. To determine whether RGO altered the physicochemical properties of the medicaments, flowability and pH were measured. A P-value of <0.05 was considered to indicate statistical significance.

RESULTS

In the CleaniCal group, bacterial viability, eDNA levels, and extracellular polymeric substrate (EPS) were significantly lower in the presence of RGO. However, only bacterial viability significantly differed in the other groups. PEG resulted in the highest cell viability among the vehicles. Furthermore, there was no significant difference in flowability or pH in relation to the inclusion of RGO.

CONCLUSION

The results suggest that RGO enhances the antibacterial effect of intracanal medicaments containing NMP.

Microwave radiofrequencies, 5G, 6G, graphene nanomaterials: Technologies used in neurological warfare

Background

Scientific literature, with no conflicts of interest, shows that even below the limits defined by the International Commission on Non-Ionizing Radiation Protection, microwaves from telecommunication technologies cause numerous health effects: neurological, oxidative stress, carcinogenicity, deoxyribonucleic acid and immune system damage, electro-hypersensitivity. The majority of these biological effects of non-thermal microwave radiation have been known since the 1970s.

Methods

Detailed scientific, political, and military documents were analyzed. Most of the scientific literature comes from PubMed. The other articles (except for a few) come from impacted journals . The rare scientific documents that were not peer reviewed were produced by recognized scientists in their fields. The rest of the documentation comes from official sources: political (e.g., European Union and World Health Organization), military (e.g., US Air Force and NATO), patents, and national newspapers.

Results

(1) Since their emergence, the authorities have deployed and encouraged the use of wireless technologies (2G, 3G, 4G, WiFi, WiMAX, DECT, Bluetooth, cell phone towers/masts/base stations, small cells, etc.) in full awareness of their harmful effects on health. (2) Consequences of microwave radiation from communication networks are comparable to the effects of low-power directed-energy microwave weapons, whose objectives include behavioral modification through neurological (brain) targeting. Above 20 gigahertz, 5G behaves like an unconventional chemical weapon. (3) Biomedical engineering (via graphene-based nanomaterials) will enable brain-computer connections, linked wirelessly to the Internet of Everything through 5G and 6G networks (2030) and artificial intelligence, gradually leading to human-machine fusion (cyborg) before the 2050s.

Conclusion

Despite reports and statements from the authorities presenting the constant deployment of new wireless communication technologies, as well as medical research into nanomaterials, as society's ideal future, in-depth research into these scientific fields shows, above all, an objective linked to the current cognitive war. It could be hypothesized that, in the future, this aim will correspond to the control of humanity by machines.

Microhardness, Surface Roughness, and Wear Resistance Enhancement of Reinforced Conventional Glass Ionomer Cement Using Fluorinated Graphene Oxide Nanosheets

OBJECTIVES

 Conventional glass ionomer cements (GICs) have been considered the most prevalent restorative material however; the reduced mechanical qualities and decreased wear resistance have been the main challenges facing their wide clinical application. This study was designed to assess the mechanical properties of fluorinated graphene (FG) oxide-modified conventional GIC.

MATERIALS AND METHODS

 Composites of FG/GIC samples were prepared using (Medifil from PROMEDICA, Germany, shade A3) at different concentrations (0wt%) control group and (1wt%, 2wt% and 3wt% FG) groups using cylindrical molds (3mm × 6mm). FG was prepared using hydrothermal technique and characterized using XPERT-PRO Powder Diffractometer system for X-ray diffraction analysis and JEOL JEM-2100 high resolution transmission electron microscope. Vickers' hardness and wear resistance of GI samples were measured. Mechanical abrasion was performed via three-body tooth brushing wear test using ROBOTA chewing simulator coupled with a thermocycling protocol (Model ACH-09075DC-T, AD-Tech Technology Co., Ltd., Leinfelden-Echterdingen, Germany).

STATISTICAL ANALYSIS

 Comparisons between groups with respect to normally distributed numeric variables were performed using one-way analysis of variance test followed by posthoc test. While paired t-test was utilized for comparing data within the same group.

RESULTS

The surface roughness values of GICs (1wt% FG) and (2wt% FG) composites were significantly lower than those of the control and 3wt%FG groups. Vickers' hardness numbers were significantly higher in FG/GICs composites than in the control group (p≤0.05).

CONCLUSION

 GIC/FG combinations have sufficient strength to resist the occlusion stresses with improved hardness as compared with conventional GIC. GIC/FG appeared to be a promising restorative material.

Impact of graphene incorporation in dental implants-A scoping review

There are numerous variables governing the formation of new bone around a dental implant. Of those variables, the implant surface is an important factor influencing the quality of osseointergration. Numerous techniques and materials have been used to alter the surface of an implant to enhance osseointergration and improve the survival and success rate. One such modification is utilizing graphene to modify the surface of an implant. This paper summarizes data collected form articles published in online databases in the past 10 years about the various means of modifying the implant surfaces and provides an in-depth review of the impact of graphene incorporation in dental implants. The document comprised of different sections and emphasized on the use of graphene as an implant surface coating material. The role of graphene on flexural strength, hardness and corrosion resistance have been discussed under mechanical properties whereas the potential of this combination on the osteogenesis, osseointergration and soft tissue seal is covered under biological properties. Lastly, how this combination acts as a drug delivery carrier and renders antimicrobial property has been addressed under pharmacological properties. This review has highlighted the various applications of graphene in the field of implant dentistry. It has outlined the various implant surface modifying methods and thrown light on the various affect this combination has on the mechanical, biological and pharmacological properties. Considering the various research done on the material, it can be concluded that graphene does have a bright future in implant dentistry and continued research in this area will provide fruitful benefits.

Sealing ability of AH Plus endodontic sealer, seal apex, multi-walled carbon nanotube-incorporated AH plus and carbon nanotube-incorporated seal apex using dye penetration microleakage

This study evaluates the sealing ability of multi-walled carbon nanotube (MWCNT)-incorporated root canal sealers in the apical third of the root canal. Fifty extracted single-rooted human teeth were divided into five groups: control (no sealer), MWCNT-incorporated AH Plus, MWCNT-incorporated Seal Apex, AH Plus and Seal Apex. The sealing ability was assessed through dye penetration microleakage. Results indicated that the MWCNT-incorporated sealers exhibited significantly less microleakage compared to traditional sealers, with MWCNT-incorporated AH Plus showing the least leakage. The control group exhibited the highest microleakage. MWCNTs enhanced the sealing efficacy by improving sealer adaptation to the canal walls. These findings highlight the potential of carbon nanotube-enhanced sealers to improve endodontic treatment outcomes. Further studies incorporating in vivo models and longer evaluation periods are recommended to confirm the clinical applicability of these advanced materials.

Effect of Graphene Oxide Nanoparticles Incorporation on the Mechanical Properties of a Resin-Modified Glass Ionomer Cement

The objective of this study was to evaluate the effect of incorporating different concentrations of graphene oxide (GO) nanoparticles on the mechanical properties of a resin-modified glass ionomer cement (RMGIC). A commercial RMGIC (Resiglass R, Biodinâmica) was modified by incorporating 0.1% and 0.5% (by weight) of GO into the powder's material. An unmodified RMGIC was used as a control group. Powder samples were characterized using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Specimens were fabricated and subjected to flexural strength (n = 15), modulus of elasticity (n = 15), Vicker's microhardness (n = 10), and surface roughness tests (n = 10). Data were analyzed using one-way ANOVA and Tukey's post hoc test (α = 5%). Experimental groups' powder demonstrated a homogeneous dispersion of GO. No statistically significant difference was observed in flexural strength (p = 0.067) and modulus of elasticity (p = 0.143) tests. The groups containing 0.1% and 0.5% GO showed significantly higher microhardness and lower surface roughness values (p < 0.001) compared to the control group. The incorporation of GO nanoparticles at concentrations of 0.1% and 0.5% improved the microhardness and surface roughness without negatively affecting the flexural strength and modulus of elasticity of an RMGIC.

Strategies and mechanisms targeting Enterococcus faecalis biofilms associated with endodontic infections: a comprehensive review

Enterococcus faecalis is one of the main microorganisms that infects root canals, ranking among the most prevalent microorganisms associated with endodontic treatment failure. Given its pervasive presence in persistent endodontic infections, the successful elimination of Enterococcus faecalis is crucial for effective endodontic treatment and retreatment. Furthermore, Enterococcus faecalis can form biofilms - defense structures that microbes use to fight environmental threats. These biofilms confer resistance against host immune system attacks and antibiotic interventions. Consequently, the presence of biofilms poses a significant challenge in the complete eradication of Enterococcus faecalis and its associated disease. In response, numerous scholars have discovered promising outcomes in addressing Enterococcus faecalis biofilms within root canals and undertaken endeavors to explore more efficacious approaches in combating these biofilms. This study provides a comprehensive review of strategies and mechanisms for the removal of Enterococcus faecalis biofilms.

On the Use of Nanoparticles in Dental Implants

Results obtained in physics, chemistry and materials science on nanoparticles have drawn significant interest in the use of nanostructures on dental implants. The main focus concerns nanoscale surface modifications of titanium-based dental implants in order to increase the surface roughness and provide a better bone-implant interfacial area. Surface coatings via the sol-gel process ensure the deposition of a homogeneous layer of nanoparticles or mixtures of nanoparticles on the titanium substrate. Nanotubular structures created on the titanium surface by anodic oxidation yield an interesting nanotopography for drug release. Carbon-based nanomaterials hold great promise in the field of dentistry on account of their outstanding mechanical properties and their structural characteristics. Carbon nanomaterials that include carbon nanotubes, graphene and its derivatives (graphene oxide and graphene quantum dots) can be used as coatings of the implant surface. Their antibacterial properties as well as their ability to be functionalized with adequate chemical groups make them particularly useful for improving biocompatibility and promoting osseointegration. Nevertheless, an evaluation of their possible toxicity is required before being exploited in clinical trials.

Graphene as a promising material in orthodontics: A review

Graphene is an extraordinary material with unique mechanical, chemical, and thermal properties. Additionally, it boasts high surface area and antimicrobial properties, making it an attractive option for researchers exploring innovative materials for biomedical applications. Although there have been various studies on graphene applications in different biomedical fields, limited reviews have been conducted on its use in dentistry, and no reviews have focused on its application in the orthodontic field. This review aims to present a comprehensive overview of graphene-based materials, with an emphasis on their antibacterial mechanisms and the factors that influence these properties. Additionally, the review summarizes the dental applications of graphene, spotlighting the studies of its orthodontic application as they can be used to enhance the antibacterial and mechanical properties of orthodontic materials such as adhesives, archwires, and splints. Also, they can be utilized to enhance bone remodeling during orthodontic tooth movement. An electronic search was carried out in Scopus, PubMed, Science Direct, and Wiley Online Library digital database platforms using graphene and orthodontics as keywords. The search was restricted to English language publications without a time limit. This review highlights the need for further laboratory and clinical research using graphene-based materials to improve the properties of orthodontic materials to make them available for clinical use.

Graphene oxide/ε-poly-L-lysine self-assembled functionalized coatings improve the biocompatibility and antibacterial properties of titanium implants

The construction of an antibacterial biological coating on titanium surface plays an important role in the long-term stability of oral implant restoration. Graphene oxide (GO) has been widely studied because of its excellent antibacterial properties and osteogenic activity. However, striking a balance between its biological toxicity and antibacterial properties remains a significant challenge with GO. ε-poly-L-lysine (PLL) has broad-spectrum antibacterial activity and ultra-high safety performance. Using Layer-by-layer self-assembly technology (LBL), different layers of PLL/GO coatings and GO self-assembly coatings were assembled on the surface of titanium sheet. The materials were characterized using scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and contact angle test. The antibacterial properties of Porphyromonas gingivalis (P.g.) were analyzed through SEM, coated plate experiment, and inhibition zone experiment. CCK-8 was used to determine the cytotoxicity of the material to MC3T3 cells, and zebrafish larvae and embryos were used to determine the developmental toxicity and inflammatory effects of the material. The results show that the combined assembly of 20 layers of GO and PLL exhibits good antibacterial properties and no biological toxicity, suggesting a potential application for a titanium-based implant modification scheme.

Exploring the Horizons of Four-Dimensional Printing Technology in Dentistry

In dentistry, the integration of additive manufacturing, particularly 3D printing, has marked significant progress. However, the emergence of 4D printing, which allows materials to change shape dynamically in response to stimuli, opens up new avenues for innovation. This review sheds light on recent advancements and potential applications of 4D printing in dentistry, delving into the fundamental principles and materials involved. It emphasizes the versatility of shape-changing polymers and composites, highlighting their ability to adapt dynamically. Furthermore, the review explores the challenges and opportunities in integrating 4D printing into dental practice, including the customization of dental prosthetics, orthodontic devices, and drug delivery systems and also probing into the potential benefits of utilizing stimuli-responsive materials to improve patient comfort, treatment outcomes, and overall efficiency and the review discusses current limitations and future directions, emphasizing the importance of standardized fabrication techniques, biocompatible materials, and regulatory considerations. Owing to its diverse applications and advantages, 4D printing technology is poised to transform multiple facets of dental practice, thereby fostering the development of healthcare solutions that are more tailored, effective, and centered around patient needs.

Implications of graphene-based materials in dentistry: present and future

Since the advent of nanoscience, nanobiomaterials have been applied in the dental industry. Graphene and its derivatives have attracted the most interest of all of them due to their exceptional look, biocompatibility, multiplication differential, and antibacterial capabilities. We outlined the most recent developments about their applications to dentistry in our review. There is discussion of the synthesis processes, architectures, and characteristics of materials based on graphene. The implications of graphene and its counterparts are then meticulously gathered and described. Finally, in an effort to inspire more excellent research, this paper explores the obstacles and potential of graphene-based nanomaterials for dental aspects.

Combined effect of electrical energy and graphene oxide on Enterococcus faecalis biofilms

This study aimed to investigate the effects of electrical energy and its synergistic activity with graphene oxide (GO) in Enterococcus faecalis (E. faecalis) biofilms. The viability of E. faecalis biofilms was analyzed by colony-forming units, crystal violet staining, and confocal laser scanning microscopy. The morphologies of the biofilms and the bacterial organelles were observed by scanning electron microscopy and transmission emission microscopy (TEM), respectively. Application of electrical energy combined with 0.2% sodium hypochlorite (NaOCl) on E. faecalis in biofilms significantly decreased the bacterial viability and biofilm biomass compared to the 0.2% NaOCl-only-treated group. Furthermore, additional application of GO showed similar antibacterial effects to 0.5% NaOCl. Notably, TEM observation revealed that the bacteria treated with electric energy and GO showed damaged cell membranes. The results suggest that combination of electrical energy and GO enhances antibacterial activity of NaOCl and has the potential to be applied to root canal irrigation protocols.

In Vitro Comparison of Internal and Marginal Adaptation between Printed and Milled Onlays

STATEMENT OF PROBLEM

Nowadays, milling is still the gold standard for fabricating indirect restorations, but to overcome its disadvantages, there are alternatives, such as 3D printing.

PURPOSE

This study aimed to compare the gaps between the prepared tooth and milled and printed onlays fabricated with the same CAD design. It also aimed to determine the gap reproducibility across onlays fabricated by 3D printing and milling.

METHODS

A resin tooth was prepared for an onlay. After scanning the preparation, an onlay was designed with proprietary dental software. Next, 22 onlays were milled in a graphene-reinforced PMMA disc (Group 1), and 22 onlays were 3D-printed with a hybrid composite material (Group 2). After that, all fabricated restorations were scanned and superimposed on the scanned prepared resin tooth. Subsequently, a specific software was used to measure the margin, central, and intaglio-located gap between the milled or printed restoration and the preparation. Finally, measurements were compared with a multifactor analysis of variance.

RESULTS

The results demonstrated that printed onlays (Group 2) adapted better to the prepared tooth than the milled ones (Group 1) (p < 0.05). The comparison of standard deviations showed the better gap reproducibility of printed onlays (p < 0.05).

CONCLUSION

This study concluded that the printed onlays adapted significantly better to the prepared tooth than the milled onlays. Printed onlays also showed significantly better gap reproducibility.

Polyether ether ketone coated with nanohydroxyapatite/graphene oxide composite promotes bioactivity and antibacterial activity at the surface of the material

Polyether ether ketone (PEEK) is considered an alternative material for manufacturing dental implants. However, PEEK lacks bioactivity and antibacterial action. In a series of experiments designed to enhance the surface properties of PEEK, we present a nanohydroxyapatite (nHA) and graphene oxide (GO) composite as a coating for PEEK-based dental implants to improve biological properties and antibacterial action. PEEK discs were polished, cleaned, and coated with the composite consisting of nHA particles doped with 0.75 wt% graphene oxide by a micro-emulsion technique according to patent US8,206,813. X-ray diffraction, field emission scanning electron microscopy-energy dispersive spectroscopy, and atomic force microscopy were utilized to characterize the composite coating. The wettability of the coated and non-coated samples was assessed by optical contact angle measurement. Antibacterial action of the composite coating was explored against S. aureus and E. coli and cytotoxicity determined utilizing osteoblast-like cells and gingival fibroblasts. The findings showed that the nHA/GO composite coating, approximately 1.3 μm thick, was homogenous with few micro-cracks and adhered to the PEEK surface. The surface roughness was reduced to 21.26 nm and the wettability was improved to 54.6⁰ after coating with the composite coating. Antibacterial activity was moderate, killing 99% of S. aureus and E. coli, with acceptable levels of cytotoxicity to mammalian osteoblast-like cells and gingival fibroblasts.

Application of Graphene Oxide in Oral Surgery: A Systematic Review

The current review aims to provide an overview of the most recent research in the last 10 years on the potentials of graphene in the dental surgery field, focusing on the potential of graphene oxide (GO) applied to implant surfaces and prosthetic abutment surfaces, as well as to the membranes and scaffolds used in Guided Bone Regeneration (GBR) procedures. "Graphene oxide" and "dental surgery" and "dentistry" were the search terms utilized on the databases Scopus, Web of Science, and Pubmed, with the Boolean operator "AND" and "OR". Reviewers worked in pairs to select studies based on specific inclusion and exclusion criteria. They included animal studies, clinical studies, or case reports, and in vitro and in vivo studies. However, they excluded systematic reviews, narrative reviews, and meta-analyses. Results: Of these 293 studies, 19 publications were included in this review. The field of graphene-based engineered nanomaterials in dentistry is expanding. Aside from its superior mechanical properties, electrical conductivity, and thermal stability, graphene and its derivatives may be functionalized with a variety of bioactive compounds, allowing them to be introduced into and improved upon various scaffolds used in regenerative dentistry. This review presents state-of-the-art graphene-based dental surgery applications. Even if further studies and investigations are still needed, the GO coating could improve clinical results in the examined dental surgery fields. Better osseointegration, as well as increased antibacterial and cytocompatible qualities, can benefit GO-coated implant surgery. On bacterially contaminated implant abutment surfaces, the CO coating may provide the optimum prospects for soft tissue sealing to occur. GBR proves to be a safe and stable material, improving both bone regeneration when using GO-enhanced graft materials as well as biocompatibility and mechanical properties of GO-incorporated membranes.

Can Graphene Pave the Way to Successful Periodontal and Dental Prosthetic Treatments? A Narrative Review

Graphene, as a promising material, holds the potential to significantly enhance the field of dental practices. Incorporating graphene into dental materials imparts enhanced strength and durability, while graphene-based nanocomposites offer the prospect of innovative solutions such as antimicrobial dental implants or scaffolds. Ongoing research into graphene-based dental adhesives and composites also suggests their capacity to improve the quality and reliability of dental restorations. This narrative review aims to provide an up-to-date overview of the application of graphene derivatives in the dental domain, with a particular focus on their application in prosthodontics and periodontics. It is important to acknowledge that further research and development are imperative to fully explore the potential of graphene and ensure its safe use in dental practices.

Graphene-Based Materials in Dental Applications: Antibacterial, Biocompatible, and Bone Regenerative Properties

Graphene-based materials have been shown to have advantageous properties in biomedical and dental applications due to their high mechanical, physiochemical, antibacterial, and stem cell differentiating properties. Although graphene-based materials have displayed appropriate biocompatible properties when used in implant materials for orthopedic applications, little research has been performed to specifically test the biocompatibility of graphene for dental applications. The oral environment, compared to the body, varies greatly and must be considered when evaluating biocompatibility requirements for dental applications. This review will discuss in vitro and in vivo studies that assess graphene's cytotoxicity, antibacterial properties, and cell differentiation ability to evaluate the overall biocompatibility of graphene-based materials for dental applications. Particle shape, size, and concentration were found to be major factors that affected overall biocompatibility of graphene.

Influence of carbon and graphene oxide nanoparticle on the adhesive properties of dentin bonding polymer: A SEM, EDX, FTIR study

OBJECTIVE

This study was aimed at including 2.5 wt.% of carbon nanoparticles (CNPs) and graphene oxide NPs (GNPs) in a control adhesive (CA) and then investigate the effect of this inclusion on their mechanical properties and its adhesion to root dentin.

MATERIALS AND METHODS

Scanning electron microscopy and energy dispersive X-ray (SEM-EDX) mapping were conducted to investigate the structural features and elemental distribution of CNPs and GNPs, respectively. These NPs were further characterized by Raman spectroscopy. The adhesives were characterized by evaluating their push-out bond strength (PBS), rheological properties, degree of conversion (DC) investigation, and failure type analysis.

RESULTS

The SEM micrographs revealed that the CNPs were irregular and hexagonal, whereas the GNPs were flake-shaped. EDX analysis showed that carbon (C), oxygen (O), and zirconia (Zr) were found in the CNPs, while the GNPs were composed of C and O. The Raman spectra for CNPs and GNPs revealed their characteristic bands (CNPs-D band: 1334 cm-1, GNPs-D band: 1341 cm-1, CNPs-G band: 1650 cm-1, and GNPs-G band: 1607 cm-1). The testing verified that the highest bond strength to root dentin were detected for GNP-reinforced adhesive (33.20 ± 3.55 MPa), trailed closely by CNP-reinforced adhesive (30.48 ± 3.10 MPa), while, the CA displayed lowest values (25.11 ± 3.60 MPa). The inter-group comparisons of the NP-reinforced adhesives with the CA revealed statistically significant results (p < 0.01). Failures of adhesive nature were most common in within the adhesives and root dentin. The rheological assessment results demonstrated a reduced viscosity for all the adhesives observed at advanced angular frequencies. All the adhesives verified suitable dentin interaction shown by hybrid layer and appropriate resin tag development. A reduced DC was perceived for both NP-reinforced adhesives, compared to the CA.

CONCLUSION

The present study's findings have demonstrated that 2.5% GNP adhesive revealed the highest, suitable root dentin interaction, and acceptable rheological properties. Nevertheless, a reduced DC was observed (matched with the CA). Prospective studies probing the influence of diverse concentrations of filler NPs on the adhesive's mechanical properties to root dentin are recommended.

Medical and Dental Applications of Titania Nanoparticles: An Overview

Currently, titanium oxide (TiO₂) nanoparticles are successfully employed in human food, drugs, cosmetics, advanced medicine, and dentistry because of their non-cytotoxic, non-allergic, and bio-compatible nature when used in direct close contact with the human body. These NPs are the most versatile oxides as a result of their acceptable chemical stability, lower cost, strong oxidation properties, high refractive index, and enhanced aesthetics. These NPs are fabricated by conventional (physical and chemical) methods and the latest biological methods (biological, green, and biological derivatives), with their advantages and disadvantages in this epoch. The significance of TiO₂ NPs as a medical material includes drug delivery release, cancer therapy, orthopedic implants, biosensors, instruments, and devices, whereas their significance as a dental biomaterial involves dentifrices, oral antibacterial disinfectants, whitening agents, and adhesives. In addition, TiO₂ NPs play an important role in orthodontics (wires and brackets), endodontics (sealers and obturating materials), maxillofacial surgeries (implants and bone plates), prosthodontics (veneers, crowns, bridges, and acrylic resin dentures), and restorative dentistry (GIC and composites).

Nanomaterials in Scaffolds for Periodontal Tissue Engineering: Frontiers and Prospects

The regeneration of periodontium represents important challenges to controlling infection and achieving functional regeneration. It has been recognized that tissue engineering plays a vital role in the treatment of periodontal defects, profiting from scaffolds that create the right microenvironment and deliver signaling molecules. Attributable to the excellent physicochemical and antibacterial properties, nanomaterials show great potential in stimulating tissue regeneration in tissue engineering. This article reviewed the up-to-date development of nanomaterials in scaffolds for periodontal tissue engineering. The paper also represented the merits and defects of different materials, among which the biocompatibility, antibacterial properties, and regeneration ability were discussed in detail. To optimize the project of choosing materials and furthermore lay the foundation for constructing a series of periodontal tissue engineering scaffolds, various nanomaterials and their applications in periodontal regeneration were introduced.