Evaluating a Cobalt-Tetraphenylporphyrin Complex, Functionalized with a Reduced Graphene Oxide Nanocomposite, for Improved Tooth Whitening

Applications of graphene oxide and reduced graphene oxide in advanced dental materials and therapies

The graphene family of nanomaterials acquired significant attention in the field of dentistry due to a range of interesting properties. Graphene oxide (GO) and reduced graphene oxide (rGO) are the major graphene derivatives that are widely used in dental applications. These derivatives exhibit excellent mechanical properties, superior biocompatibility, good antibacterial properties, extreme chemical stability, and favorable tribological characteristics, thus representing highly materials for dentistry. The amphiphilic nature of GO allows covalent and noncovalent modifications that are favorable for biomedical applications. Graphene can influence the differentiation of dental pulp stem cells (DPSCs) and enhance the properties of other biomaterials. Here, we review the dental applications of GO or rGO with regards to antimicrobial activity, therapeutic drug delivery, restorative dentistry, implants, pulp regeneration, bone regeneration, periodontal tissue regeneration, biosensors, and tooth whitening.

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.

On-Demand Free Radical Release by Laser Irradiation for Photothermal-Thermodynamic Biofilm Inactivation and Tooth Whitening

Dental diseases associated with biofilm infections and tooth staining affect billions of people worldwide. In this study, we combine photothermal agents (MoS₂@BSA nanosheets, MB NSs), a thermolysis free-radical initiator (AIPH), and carbomer gel to develop laser-responsive hydrogel (MBA-CB Gel) for biofilm inactivating and tooth whitening. Under a physiological temperature without laser irradiation, MB NSs can eliminate free radicals generated from the slow decomposition of AIPH due to their antioxidative activity, thereby avoiding potential side effects. A cytotoxicity study indicates that MB NSs can protect mammalian cells from the free radicals released from AIPH without laser irradiation. Upon exposure to laser irradiation, MB NSs promote the rapid decomposition of AIPH to release free radicals by photothermal effect, suggesting their on-demand release ability of free radicals. In vitro experimental results show that the bacteria inactivation efficiency is 99.91% (3.01 log units) for planktonic Streptococcus mutans (S. mutans) and 99.98% (3.83 log units) for planktonic methicillin-resistant Staphylococcus aureus (MRSA) by the mixed solution of MB NSs and AIPH (MBA solution) under 808 nm laser irradiation (1.0 W/cm², 5 min). For S. mutans biofilms, an MBA solution can inactivate 99.97% (3.63 log units) of the bacteria under similar laser irradiation conditions. Moreover, MBA-CB Gel can whiten an indigo carmine-stained tooth under laser irradiation after 60 min of laser treatment, and the color difference (ΔE) in the teeth of the MBA-CB Gel treatment group was 10.9 times that of the control group. This study demonstrates the potential of MBA-CB Gel as a promising platform for biofilm inactivation and tooth whitening. It is worth noting that, since this study only used stained models of extracted teeth, the research results may not fully reflect the actual clinic situation. Future clinical research needs to further validate these findings.

Fracture Resistance Analysis of CAD/CAM Interim Fixed Prosthodontic Materials: PMMA, Graphene, Acetal Resin and Polysulfone

The aim of this study was to evaluate and compare the fracture resistance of temporary restorations made of polymethylmethacrylate (PMMA), graphene-modified PMMA (GRA), acetal resin (AR) and polysulfone (PS) obtained by a subtractive technique (milling) using a computer-aided design and manufacturing (CAD/CAM) system of a three-unit fixed dental prosthesis (FDP). Methods: Four groups of ten samples were fabricated for each material. Each specimen was characterized by a compression test on a universal testing machine, all specimens were loaded to fracture and the value in Newtons (N) was recorded by software connected to the testing machine. The fracture mode was evaluated on all samples using a stereomicroscope. Results: There were statistically significant differences (p value < 0.005) between PMMA and the other three materials (PMMA: 1302.71 N; GRA: 1990.02 N; RA: 1796.20 N; PS: 2234.97). PMMA presented a significantly lower value than the other materials, and PS showed the highest value. GRA and RA presented a similar range of values but they were still higher than those of PMMA. Conclusions: GRA, RA and PS are presented as valid options within the range of interim milled restorative materials and as alternatives to PMMA.

Graphene on dentistry: A bibliometric and scientometric analysis

Background

Today, the development of dental materials is a very important issue. Graphene has been used in dentistry to strengthen many materials.

Aim

The aim of this study was to analyze leading countries and to identify the preferred journals, the most commonly used keywords, and the most productive authors in the field of graphene.

Materials and Methods

The search keyword was "graphene" on the Web of Science database; the search was restricted to before 2022. The selected search from the Web of Science database included the title of articles, authors, year of publication, country, citation count, and keywords. An analysis was performed regarding citations and documents, authors, journals, and keywords using a bibliometric software program. All articles were evaluated and subjected to scientometric analysis.

Results

Twenty six articles were included in the study. There has been a remarkable increase in published articles from past to present, and a regular increase is observed in the number of citations. Dental Materials has highest number of publications among the articles included in the present study. Dr. Rosa, who had the highest number of citations, is also the most effective author. Graphene has many studies in dentistry with different materials. As per the data obtained, graphene, graphene oxide, and peri-implantitis are the most used keywords and Singapore and China are at the forefront of the countries where the articles are published.

Conclusion

This bibliometric analysis reveals the progress and trend of research on graphene in dentistry and extensive collaborations between authors, countries, and institutions. The findings of this study can help inspire researchers to plan new studies and collaborate on graphene.

Evaluation of Cytotoxic Effect of Graphene Oxide Added to Mineral Trioxide Aggregate

Aim:

Recently, although studies have shown that biomaterials containing graphene oxide (GO) in biomedicine stand out for their positive effects, the effect of GO on dental tissues when used with dental materials is not well known. The aim of this study was an evaluation of the cytotoxic effects of GO on gingival fibroblasts when it is combined in two different ratios with Mineral Trioxide Aggregate (MTA).

Materials and Methods:

In this in-vitro study, a homogenous mixture of adding +0.1 weight (wt)% and +0.3 wt% GO to Angelus MTA was created (two experimental groups) and compared with pure Angelus MTA and negative control groups. The materials were mixed according to the manufacturer’s instructions, and Teflon molds were used to form 24 disc-shaped samples for each group. The samples were divided into groups according to the simple random sampling method. The cytotoxic effect of samples was determined on gingival fibroblast cells by using the MTT test, and total oxidant status (TOS) and total antioxidant capacity (TAC) kits in 24 and 72 hours. The data were statistically analyzed using one-way ANOVA and Tukey tests.

Results:

A significant difference was found between the material-applied groups and the control group at the TAC 24 and 72 hours and between the groups containing GO and the control group at the MTT 72 hours and TAC and TOS 24 and 72 hours ( p < .05).

Conclusion:

The addition of GO to MTA increased the dose and time-based toxicity and oxidant amount, and decreased antioxidant capacity.

Nanoparticles as Next-Generation Tooth-Whitening Agents: Progress and Perspectives

Whitening agents, such as hydrogen peroxide and carbamide peroxide, are currently used in clinical applications for dental esthetic and dental care. However, the free radicals generated by whitening agents cause pathological damage; therefore, their safety issues remain controversial. Furthermore, whitening agents are known to be unstable and short-lived. Since 2001, nanoparticles (NPs) have been researched for use in tooth whitening. Importantly, nanoparticles not only function as abrasives but also release reactive oxygen species and help remineralization. This review outlines the historical development of several NPs based on their whitening effects and side effects. NPs can be categorized into metals or metal oxides, ceramic particles, graphene oxide, and piezoelectric particles. Moreover, the status quo and future prospects are discussed, and recent progress in the development of NPs and their applications in various fields requiring tooth whitening is examined. This review promotes the research and development of next-generation NPs for use in tooth whitening.

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

With the development of nanotechnology, nanomaterials have been used in dental fields over the past years. Among them, graphene and its derivatives have attracted great attentions, owing to their excellent physicochemical property, morphology, biocompatibility, multi-differentiation activity, and antimicrobial activity. In our review, we summarized the recent progress about their applications on the dentistry. The synthesis methods, structures, and properties of graphene-based materials are discussed. Then, the dental applications of graphene-based materials are emphatically collected and described. Finally, the challenges and outlooks of graphene-based nanomaterials on the dental applications are discussed in this paper, aiming at inspiring more excellent studies.

Photothermal-Enhanced Fenton-like Catalytic Activity of Oxygen-Deficient Nanotitania for Efficient and Safe Tooth Whitening

The growing demand for charming smiles has led to the popularization of tooth bleaching procedures. Current tooth bleaching products with high-concentration hydrogen peroxide (HP, 30-40%) are effective but detrimental due to the increased risk of enamel destruction, tooth sensitivity, and gingival irritation. Herein, we reported a less-destructive and efficient tooth whitening strategy with a low-concentration HP, which was realized by the remarkably enhanced Fenton-like catalytic activity of oxygen-deficient TiO₂ (TiO_2-x). TiO_2-x nanoparticles were synthesized with a modified solid-state chemical reduction approach with NaBH₄. The Fenton-like activity of TiO_2-x was optimized by manipulating oxygen vacancy (OV) concentration and further promoted by the near-infrared (NIR)-induced photothermal effect of TiO_2-x. The TiO_2-x sample named BT45 was chosen due to the highest methylene blue (MB) adsorption ability and Fenton-like activity among acquired samples. The photothermal property of BT45 under 808 nm NIR irradiation was verified and its enhancement on Fenton-like activity was also studied. The BT45/HP + NIR group performed significantly better in tooth whitening than the HP + NIR group on various discolored teeth (stained by Orange II, tea, or rhodamine B). Excitingly, the same tooth whitening performance as the Opalescence Boost, a tooth bleaching product containing 40% HP, was obtained by a self-produced bleaching gel based on this novel system containing 12% HP. Besides, negligible enamel destruction, safe temperature range, and good cytocompatibility of TiO_2-x nanoparticles also demonstrated the safety of this tooth bleaching strategy. This work indicated that the photothermal-enhanced Fenton-like performance of the TiO_2-x-based system is highly promising in tooth bleaching application and can also be extended to other biomedical applications.

Nanomaterials in Dentistry: State of the Art and Future Challenges

Nanomaterials are commonly considered as those materials in which the shape and molecular composition at a nanometer scale can be controlled. Subsequently, they present extraordinary properties that are being useful for the development of new and improved applications in many fields, including medicine. In dentistry, several research efforts are being conducted, especially during the last decade, for the improvement of the properties of materials used in dentistry. The objective of the present article is to offer the audience a complete and comprehensive review of the main applications that have been developed in dentistry, by the use of these materials, during the last two decades. It was shown how these materials are improving the treatments in mainly all the important areas of dentistry, such as endodontics, periodontics, implants, tissue engineering and restorative dentistry. The scope of the present review is, subsequently, to revise the main applications regarding nano-shaped materials in dentistry, including nanorods, nanofibers, nanotubes, nanospheres/nanoparticles, and zeolites and other orders porous materials. The results of the bibliographic analysis show that the most explored nanomaterials in dentistry are graphene and carbon nanotubes, and their derivatives. A detailed analysis and a comparative study of their applications show that, although they are quite similar, graphene-based materials seem to be more promising for most of the applications of interest in dentistry. The bibliographic study also demonstrated the potential of zeolite-based materials, although the low number of studies on their applications shows that they have not been totally explored, as well as other porous nanomaterials that have found important applications in medicine, such as metal organic frameworks, have not been explored. Subsequently, it is expected that the research effort will concentrate on graphene and zeolite-based materials in the coming years. Thus, the present review paper presents a detailed bibliographic study, with more than 200 references, in order to briefly describe the main achievements that have been described in dentistry using nanomaterials, compare and analyze them in a critical way, with the aim of predicting the future challenges.

Titanium dioxide nanotubes incorporated into bleaching agents: physicochemical characterization and enamel color change

Titanium dioxide nanotubes are nanostructures that can accelerate the oxidation reaction of bleaching procedures and promote a more effective whitening effect.

Graphene Oxide Applications in Dentistry: Integrative Literature Review

AbstractGraphene and its derivatives, such as graphene oxide, represent the greatest potential materials in terms of biomaterials due to their excellent physical-chemical and biological properties. Thus, the present study has developed an integrative literature review in order to evaluate the capacity of graphene oxide to replace metal biomaterials currently used in Dentistry. For this purpose, LILACS, SciELO and PubMED databases were evaluated, with the following descriptors: graphene, biomaterials and Odontology, adapted for each database used. Firstly, the descriptors were searched separately and, later, the Boolean operator AND was used to define a search strategy. The articles were selected according to the following inclusion criteria: articles in Portuguese, English and Spanish, published and indexed in the databases, in the last ten years, with texts available in full and regarding the topic under study. A total of 14 scientific papers were found and 10 of them were selected for this review. After the critical reading of each article, it was possible to observe that graphene and its derivates present great biocompatibility, excellent mechanical, electrical and thermic properties, high flexibility, low density and a huge potential to be explored in health science. It is also important to highlight its potential application as a coating of metal biomaterials. Keywords: Biocompatible Materials. Materials Testing. Dentistry.   ResumoO grafeno e seus derivados, como o óxido de grafeno, representam atualmente o maior potencial em termos de biomateriais, devido às suas excelentes propriedades físico-químicas e de biocompatibilidade. Assim, o presente estudo teve como premissa conduzir uma revisão integrativa da literatura de modo a verificar a capacidade do óxido de grafeno em substituir os biomateriais metálicos atualmente utilizados na Odontologia. Para isto, foram utilizadas as bases de dados Lilacs, SciELO e Pubmed, com os seguintes descritores: grafeno, biomateriais e Odontologia, adaptados para cada base de dados utilizada. Primeiramente, os descritores foram pesquisados isoladamente e, posteriormente, o operador booleano AND foi utilizado de modo a definir uma estratégia de busca. Os artigos foram selecionados de acordo com os critérios de inclusão: artigos em Português, Inglês e Espanhol, publicados e indexados nas referidas bases de dados, nos últimos dez anos, com texto disponível na íntegra e que retratassem a temática em estudo. Foram encontrados um total de 14 artigos científicos e, dez destes artigos foram selecionados para compor a revisão. A partir da leitura crítica de cada artigo, foi possível observar que o grafeno e seus derivados apresentam uma alta biocompatibilidade, notáveis propriedades mecânicas, elétricas e térmicas, alta flexibilidade, baixa densidade de massa e um enorme potencial a ser explorado para beneficiar a área da saúde. Deve-se, também, destacar sua potencial aplicação como revestimento de materiais metálicos implantáveis. Palavras-chave: Materiais Biocompatíveis. Teste de Materiais. Odontologia.

Graphene-Based Nanomaterials for Tissue Engineering in the Dental Field

The world of dentistry is approaching graphene-based nanomaterials as substitutes for tissue engineering. Apart from its exceptional mechanical strength, electrical conductivity and thermal stability, graphene and its derivatives can be functionalized with several bioactive molecules. They can also be incorporated into different scaffolds used in regenerative dentistry, generating nanocomposites with improved characteristics. This review presents the state of the art of graphene-based nanomaterial applications in the dental field. We first discuss the interactions between cells and graphene, summarizing the available in vitro and in vivo studies concerning graphene biocompatibility and cytotoxicity. We then highlight the role of graphene-based nanomaterials in stem cell control, in terms of adhesion, proliferation and differentiation. Particular attention will be given to stem cells of dental origin, such as those isolated from dental pulp, periodontal ligament or dental follicle. The review then discusses the interactions between graphene-based nanomaterials with cells of the immune system; we also focus on the antibacterial activity of graphene nanomaterials. In the last section, we offer our perspectives on the various opportunities facing the use of graphene and its derivatives in associations with titanium dental implants, membranes for bone regeneration, resins, cements and adhesives as well as for tooth-whitening procedures.