Recent Progress on the Applications of Nanomaterials and Nano-Characterization Techniques in Endodontics: A Review

Antimicrobial Effects of Formulations of Various Nanoparticles and Calcium Hydroxide as Intra-canal Medications Against Enterococcus faecalis: A Systematic Review

The combination of calcium hydroxide (Ca(OH)₂) and nanoparticles (NPs) offers a promising approach to improving the efficacy of intra-canal treatments. Their synergistic effects can enhance antimicrobial action, improve penetration, and promote better healing outcomes in endodontic therapy. This review article examines the antimicrobial efficacy of various nanoparticles combined with Ca(OH)₂ against Enterococcus faecalis (E. faecalis) compared to Ca(OH)₂ alone as an intra-canal medicament. The analysis is based on in vitro studies involving bacterial inoculation on human-extracted teeth. Publications from 2013 to 2024 were retrieved from databases such as PubMed, Scopus, the Cochrane Library, and EBSCOhost and were screened according to specific inclusion criteria. Ultimately, 11 studies met these criteria for inclusion in the systematic review. A meta-analysis was not conducted due to the heterogeneity of the studies regarding the duration of medicament application, analytical methods, and result interpretations. The results indicate that NPs combined with calcium hydroxide exhibit superior bactericidal effects compared to Ca(OH)₂ alone, suggesting their potential as effective intra-canal medicaments. Thus, a systematic review concluded that nanoparticle-based Ca(OH)₂ intra-canal medicaments exhibit superior antibacterial/antimicrobial capabilities against E. faecalis when compared to Ca(OH)₂individually.

Clinicians' perspectives, inducements, preferences, and clinical experiences regarding the use of electronic apex locator and apex locator integrated engine-driven instrumentation: a cross-sectional study

BACKGROUND

This study aimed to investigate the perspectives, preferences, and clinical experiences regarding using electronic apex locator and apex locator integrated instrumentation of dentists and endodontists.

METHODS

A web-based questionnaire consisting of 3 parts and 23 closed-ended questions to achieve the objective of the study was carried out in ethical conditions between August and October 2023. The first part of survey included demographic information, while the second part was about evaluating electronic apex locator usage. In the last part, only participants' use of apex locator-integrated instrumentation was evaluated. Data were analyzed at a significance level of p < 0.05.

RESULTS

A total of 297 clinicians, including 59 endodontists and 34 endodontic residents/Ph.D. students participated in the questionnaire. Endodontists and endodontic residents/Ph.D. students perform statistically significantly more root canal treatments per week on average (p = 0.001). For the working length determination method (multiple option question), 78.5% of participants use an electronic apex locator and 39.7% apex locator-integrated engines. However, the preference rate for electronic apex determination technique was generally 95.6%, with the full rate confirmation of endodontists and endodontic residents/Ph.D. students (100%). A total of 21 endodontists out of 59 prefer apex locator integrated engine-driven instrumentation. Although many of these specialized clinicians use this technique, they stated that they measure electronic working length passively for confirmation of the working length before (90.5%) and after the preparation (66.7%).

CONCLUSIONS

Dentists, as well as endodontists, are skeptical about apex locator-integrated engine-driven instrumentation. Using this technique as a supporter rather than a primary way for preparation within safe limits may give safer results in terms of treatment outcomes.

Advances in hybridized nanoarchitectures for improved oro-dental health

On a global note, oral health plays a critical role in improving the overall human health. In this vein, dental-related issues with dentin exposure often facilitate the risk of developing various oral-related diseases in gums and teeth. Several oral-based ailments include gums-associated (gingivitis or periodontitis), tooth-based (dental caries, root infection, enamel erosion, and edentulous or total tooth loss), as well as miscellaneous diseases in the buccal or oral cavity (bad breath, mouth sores, and oral cancer). Although established conventional treatment modalities have been available to improve oral health, these therapeutic options suffer from several limitations, such as fail to eradicate bacterial biofilms, deprived regeneration of dental pulp cells, and poor remineralization of teeth, resulting in dental emergencies. To this end, the advent of nanotechnology has resulted in the development of various innovative nanoarchitectured composites from diverse sources. This review presents a comprehensive overview of different nanoarchitectured composites for improving overall oral health. Initially, we emphasize various oral-related diseases, providing detailed pathological circumstances and their effects on human health along with deficiencies of the conventional therapeutic modalities. Further, the importance of various nanostructured components is emphasized, highlighting their predominant actions in solving crucial dental issues, such as anti-bacterial, remineralization, and tissue regeneration abilities. In addition to an emphasis on the synthesis of different nanostructures, various nano-therapeutic solutions from diverse sources are discussed, including natural (plant, animal, and marine)-based components and other synthetic (organic- and inorganic-) architectures, as well as their composites for improving oral health. Finally, we summarize the article with an interesting outlook on overcoming the challenges of translating these innovative platforms to clinics.

0,1,2,3D nanostructures, types of bulk nanostructured materials, and drug nanocrystals: An overview

Functional materials are required to meet the needs of society, such as environmental protection, energy storage and conversion, integrated product production, biological and medical processing. bulk nanostructured materials are a research concept that combines nanotechnology with other research fields such as supramolecular chemistry, materials science, and life science to develop logically functional materials from nanodevices. In this review article, nanostructures are synthetized by different methods based on the types and nature of the nanomaterials. In a broad sense "top-down" and "bottom-up" are the two foremost methods to synthesize nanomaterials. In top-down method bulk materials have been reduced to nanomaterials, and in case of bottom-up method, the nanomaterials are synthesized from elementary level. The different methods which are being used to synthesize nanomaterials are chemical vapor deposition method, thermal decomposition, hydrothermal synthesis, solvothermal method, pulsed laser ablation, templating method, combustion method, microwave synthesis, gas phase method, and conventional Sol-Gel method. We also briefly discuss the various physical and chemical methods for producing nanomaterials. We then discuss the applications of functional materials in many areas such as energy storage, supercapacitors, sensors, wastewater treatment, and other biological applications such as drug delivery and drug nanocrystals. Finally, future challenges in materials nanoarchitecture and concepts for further development of functional nanomaterials are briefly discussed.

Contemporary research trends on nanoparticles in endodontics: a bibliometric and scientometric analysis of the top 100 most-cited articles

Objectives

Advancements in nanotechnology have led to the widespread usage of nanoparticles in the endodontic field. This bibliometric study aimed to determine and analyze the top 100 most-cited articles about nanoparticles in endodontics from 2000 to 2022.

Materials and Methods

A detailed electronic search was conducted on the "Clarivate Analytics Web of Science, All Databases" to receive the most-cited articles related to the topic. Articles were ranked in descending order based on their citation counts, and the first 100 were selected for bibliometric analysis. Parameters such as citation density, publication year, journal, country, institution, author, study design, study field, evidence level, and keywords were analyzed.

Results

The top 100 most-cited articles received 4,698 citations (16-271) with 970.21 (1.91-181) citation density in total. Among decades, citations were significantly higher in 2011-2022 (p < 0.001). Journal of Endodontics had the largest number of publications. Canada and the University of Toronto made the highest contribution as country and institution, respectively. Anil Kishen was the 1 who participated in the largest number of articles. The majority of the articles were designed in vitro. The main study field was "antibacterial effect." Among keywords, "nanoparticles" followed by "Enterococcus faecalis" were used more frequently.

Conclusions

Developments in nanotechnology had an impact on the increasing number of studies in recent years. This bibliometric study provides a comprehensive view of nanoparticle advances and trends using citation analysis.

Modern Therapeutic Strategies in Endodontics and Restorative Dentistry

Modern endodontics aims to reduce or eliminate bacterial load inside root canals [...].

Smear Layer and Debris Removal from Root Canals Comparing Traditional Syringe Irrigation and 3D Cleaning: An Ex Vivo Study

Background: Endodontic treatment objectives comprise eliminating or decreasing bacterial load inside the complex endodontic space. Removing the smear layer and debris becomes mandatory to achieve good three-dimensional (3D) cleaning. Aim: This study assesses the difference in smear layer removal using the 3D cleaning technique and traditional syringe needle irrigation. The 3D cleaning technique includes the ultrasonic activation of intracanal-heated NaOCl. Materials and Methods: Our current study used single-rooted human mandibular premolar teeth to test the earlier-mentioned technique (n = 30). Initially, an endodontic access cavity was performed. Consequently, specimens were randomly distributed into three study groups according to irrigation protocol. The groups were Group 1, where the traditional syringe needle irrigation system was applied; Group 2, where the 3D cleaning technique was performed; and Group 3, in which teeth remained uncleaned as it was regarded as the control group. Once the experiment was completed, the teeth were decoronated at the cementoenamel junction (CEJ) and examined using scanning electron microscopy (SEM). Debris and smear layers were viewed in 1000× magnification and scored. Results: Statistical analysis was performed with a standard statistical software package (SPSS, version 28.0; SPSS IBM, Armonk, NY, USA). Data were analyzed with a nonparametric analysis of variance (Kruskal−Wallis ANOVA) among the groups tested and among the thirds of the canals. The level of significance was set at p < 0.05. A statistically significant (p < 0.05) lower mean smear layer and debris score was observed in both study groups compared to the control group. Group 2 showed better results compared to Group 1. Conclusions: The present study concluded that the 3D cleaning technique is an effective irrigation method for removing debris and smear layers. Future research, such as CLSM (Confocal Laser Scanning Microscopy) and Histological study, should be employed to confirm this study’s conclusion.

Treated Dentin Matrix in Tissue Regeneration: Recent Advances

Tissue engineering is a new therapeutic strategy used to repair serious damage caused by trauma, a tumor or other major diseases, either for vital organs or tissues sited in the oral cavity. Scaffold materials are an indispensable part of this. As an extracellular-matrix-based bio-material, treated dentin matrixes have become promising tissue engineering scaffolds due to their unique natural structure, astonishing biological induction activity and benign bio-compatibility. Furthermore, it is important to note that besides its high bio-activity, a treated dentin matrix can also serve as a carrier and release controller for drug molecules and bio-active agents to contribute to tissue regeneration and immunomodulation processes. This paper describes the research advances of treated dentin matrixes in tissue regeneration from the aspects of its vital properties, biologically inductive abilities and application explorations. Furthermore, we present the concerning challenges of signaling mechanisms, source extension, individualized 3D printing and drug delivery system construction during our investigation into the treated dentin matrix. This paper is expected to provide a reference for further research on treated dentin matrixes in tissue regeneration and better promote the development of relevant disease treatment approaches.

Development of Root Caries Prevention by Nano-Hydroxyapatite Coating and Improvement of Dentin Acid Resistance

There is no established method for optimizing the use of dentin to prevent root caries, which are increasing in the elderly population. This study aimed to develop a new approach for root caries prevention by focusing on bioapatite (BioHap), a new biomaterial, combined with fluoride. Bovine dentin was used as a sample, and an acid challenge was performed in three groups: no fluoride (control group), acidulated phosphate fluoride treatment (APF group), and BioHap + APF treatment (BioHap group). After applying the new compound, the acid resistance of dentin was compared with that of APF alone. The BioHap group had fewer defects and an increased surface hardness than the APF group. The BioHap group had the smallest lesion depth and least mineral loss among all groups. Using a scanning electron microscope in the BioHap group showed the closure of dentinal tubules and a coating on the surface. The BioHap group maintained a coating and had higher acid resistance than the APF group. The coating prevents acid penetration, and the small particle size of BioHap and its excellent reactivity with fluoride are thought to have contributed to the improvement of acid resistance in dentin. Topical fluoride application using BioHap protects against root caries.