Journal of endodontics最新文献

Introduction: This study aimed to evaluate the effects of a virtual reality haptic simulator (VRHS, VirTeaSy Dental) and a mobile application (Dental EndoMaster) on the manual competency, stress, and self-confidence levels of 4th-year dental students in endodontic clinical practice.

Methods: Thirty dental students were randomly assigned to 3 groups as follows (n = 10): Group 1 (VRHS), Group 2 (mobile application), and Group 3 (control). Before clinical training, Groups 1 and 2 completed 3 standardized practice sessions and one final assessment session using VRHS and a mobile application. In contrast, Group 3 directly started with the clinical procedure without prior exposure to VRHS or the mobile application. All students performed access cavity preparations on maxillary incisors diagnosed with chronic apical periodontitis. Clinical performance was evaluated by an endodontist. Self-clinical scores and drilling time were recorded. Upon the termination of clinical practice, students completed a self-confidence survey. Stress levels were measured using a visual analog scale at different time points. Statistical analyses were conducted with significance set at P < .05.

Results: Students in Group 1 showed significantly higher clinical and self-clinical scores and reduced drilling time compared to Group 3 (P < .05). Students in Groups 1 and 2 exhibited lower stress levels before the clinical procedures (P < .05). Groups 1 and 2 reported greater self-confidence and perceived preparedness for clinical endodontic procedures compared to Group 3.

Conclusions: The integration of artificial inteligence-enhanced VRHS and a mobile application into endodontic training significantly enhanced students' clinical performance, reduced stress levels, and increased self-confidence during their first clinical procedures.

Introduction: This study aimed to evaluate the effect of topical application of strontium under thermocycling conditions on average crack length, crack density, tubular density, and tubular diameter in both healthy and diabetic root dentin.

Methods: Sixty mid-root dentin discs from extracted premolars (n = 30 healthy, n = 30 diabetic) were allocated to 6 groups: no Sr treatment (CTL), Sr treatment before thermocycling (Sr-PRE), or Sr after thermocycling (Sr-POST) for both metabolic conditions. Sr treatment involved a 5-minute application of 1.8 μM L-ascorbic acid-2-phosphate strontium solution. All specimens underwent 2000 thermal cycles (5°C-55°C). Scanning electron microscopy was used to assessed average crack length, crack density, tubule density, and tubule diameter. Data were analyzed using two-way ANOVA (metabolic status × Sr regimen; α = 0.05) using GraphPad Prism software (10.5.0.774 version; GraphPad Software, San Diego, CA).

Results: Diabetic dentin exhibited significantly greater crack growth (P < .05) and tubule density (P < .05) after thermocycling compared to healthy controls. Sr-PRE reduced crack growth by approximately 70% in diabetic dentin and 56% in healthy dentin (P < .05), significantly lowering tubule density and diameter. Sr-POST provided intermediate protection. Sr's protective effects were most pronounced in diabetic dentin.

Conclusions: A brief chairside Sr rinse applied before thermal stress markedly reduced crack metrics and tubule density/diameter relative to controls after thermocycling.

Cracked teeth represent a growing concern in endodontic practice, driven by biomechanical, evolutionary, and lifestyle factors. While traditionally approached as a condition requiring reactive treatment, contemporary endodontics must now shift toward prevention. This article explores the multifactorial nature of cracked teeth, including parafunctional habits, malocclusion, modern dietary patterns, and the evolutionary mismatch between human dentition and present-day lifestyles. The paper outlines key risk factors such as bruxism, malocclusion, and enamel demineralization, while also discussing effective preventive strategies. These include occlusal assessment, orthodontic or equilibration interventions, dietary counseling, and use of occlusal splints. Management of asymptomatic cracks and stabilization through full-coverage restorations or bonded restorations is emphasized to reduce the likelihood of structural failure. For teeth requiring endodontic therapy, the inclusion of bonded intraorifice barriers, timely restorations, and occlusal adjustment significantly improves long-term outcomes. Notably, recent evidence challenges outdated assumptions regarding poor prognosis for cracked teeth, highlighting the effectiveness of interdisciplinary protocols. The article calls for a paradigm shift in endodontic care from solely treating cracked teeth to actively preventing their occurrence. By integrating principles from preventive medicine and anthropology, endodontists can better preserve natural dentition. Ultimately, ensuring that the first diagnosed crack is the last one aligns with both ethical obligations and the long-term success of endodontic treatment.

Introduction: Immune cell-mesenchymal stem cell interactions modulate repair and regeneration, with cell-to-cell interactions being a necessary component facilitating this crosstalk. This study used a collagen-based organoid model to examine direct cell-to-cell interactions between stem cells from apical papilla (SCAP) and macrophages (MQ). The aim was to better understand how adhesion molecules contribute to apical periodontitis dynamics in the immature permanent tooth.

Methods: Two-dimensional SCAP-MQ co-cultures were compared to three-dimensional (3D) SCAP-MQ self-assembled tissue constructs under 3 conditions: non-stimulated, lipopolysaccharide (LPS), and interleukin (IL)-4 for up to 7 days. Expression of 5 candidate adhesion molecules (CD200, CD200 R, intercellular adhesion molecule (ICAM)-1, N-cadherin, and lymphocyte function-associated antigen (LFA)-1) were assessed by quantitative real time polymerase chain reaction and confocal microscopy.

Results: LPS decreases CD200 and CD200 R immunofluorescence in an organoid model (P < .05). N-CADHERIN gene expression increased on day 5 in the 3D model in response to LPS (P < .05). LFA-1 showed a trend toward increased immunofluorescence in the juxtacrine zone of the organoid model under LPS stimulation, though this difference was not significant. ICAM-1 gene expression in the 2D model increased in response to LPS (P < .05) but no change was observed with IL-4.

Conclusion: Extracellular collagen and inflammatory conditions modulate adhesion molecule expression in SCAP-MQ co-cultures. LPS promoted N-cadherin, ICAM-1, and LFA-1 expression, while IL-4 increased CD200, CD200 R, and ICAM-1. These findings highlight the molecular mechanisms underlying SCAP-MQ interactions and validate the use of 3D models to potentially inform future therapeutic strategies for enhancing pulpal regeneration.

Introduction: Successful endodontic therapy depends on effective microbial control and the biocompatibility of irrigants. While sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) are widely used, concerns regarding their cytotoxic and genotoxic potential remain. Triton, a novel all-in-one irrigant, combines NaOCl with chelators and surfactants, potentially simplifying irrigation. This study aimed to evaluate the cytotoxicity and genotoxicity of Triton compared with NaOCl and EDTA in human periodontal ligament fibroblasts.

Methods: Human periodontal ligament fibroblasts were exposed to 4% NaOCl, 6% NaOCl, 17% EDTA, and Triton for 1 and 10 minutes. Cytotoxicity was assessed using the Cell Counting Kit-8 assay. Genotoxicity was evaluated via immunofluorescence staining for γH2AX and 53BP1, markers of DNA double-strand breaks. A total of 0.9% sodium chloride and phosphate-buffered saline served as the negative controls, while lysis buffer and hydrogen peroxide served as positive controls in respective studies.

Results: Triton exhibited cytotoxicity comparable to 4% and 6% NaOCl but significantly lower than 17% EDTA. Immunofluorescence analysis showed no genotoxicity with Triton or NaOCl at either concentration or time point. In contrast, 17% EDTA induced a time-dependent increase in γH2AX/53BP1 colocalized foci, indicating DNA damage.

Conclusions: Triton has shown cytotoxicity and genotoxicity levels comparable to those of NaOCl while demonstrating significantly lower toxicity than 17% EDTA in both assays. These findings suggest that Triton may serve as a beneficial addition to the current endodontic irrigation armamentarium, offering a simplified protocol.

Introduction: This bibliometric review aimed to analyze research trends and key characteristics of studies related to ethylenediaminetetraacetic acid (EDTA) in endodontics.

Methods: A comprehensive search was performed in May 2025 using the Web of Science Core Collection database. All study types were considered. Two independent reviewers extracted data on citations, publication year, journal, study design, topic, country, continent, institutions, authorship, and keywords. VOSviewer software was used to generate collaboration networks, and Spearman's correlation assessed relationships between variables.

Results: A total of 1947 articles were identified, of which 944 met the inclusion criteria. The most cited article received 466 citations. The Journal of Endodontics was the most prevalent journal (n = 239). Laboratory studies represented 93% of all included publications. The most common research topics involved comparisons between EDTA and other chelating agents, as well as the deleterious effects of EDTA on dentin (n = 310). Scanning electron microscopy was the most widely used imaging technique (n = 277). The most productive author was Ballal NV (n = 24). Brazil led in number of publications (n = 180), while the Asian continent accounted for the highest overall output (n = 407). Spearman's analysis showed a strong negative correlation between citation count and publication year (r = -0.792), and a weak positive correlation with journal impact factor (r = 0.235).

Conclusions: This review demonstrates sustained global interest in EDTA. Brazil and Turkey are key contributors to this field. The predominance of in vitro studies highlights the need for future research to include more clinical trials and systematic reviews to enhance the strength of evidence.

Introduction: Over the past 2 decades, numerous researchers have focused on identifying cell populations capable of regenerating the pulp-dentin complex. Most research focused on dental tissue-derived mesenchymal stromal cells (dMSCs), which possess multipotent differentiation potential and can be isolated from various dental tissues. However, these dMSCs have limitations, prompting researchers to explore alternative cell sources that offer greater scalability and sustained regenerative potential while preserving the unique expression and functional profile of dMSCs. This study aimed to test the odontogenic properties of mesenchymal progenitor cells derived from human induced pluripotent stem cells (i-MPCs) as a promising alternative to dMSCs.

Methods: Patient-specific human-induced pluripotent stem cells were differentiated to generate mesenchymal progenitors via a cranial neural crest intermediate, replicating embryonic tooth development. The expression profile of the i-MPCs was assessed and compared to stem cells of the apical papilla (SCAPs) through a panel of cell surface markers: CD90, CD73, CD105, CD13, CD14, CD271, CD57, and CD146, using flow cytometry, differentiation potential through trilineage differentiation assays, and average gene expression through bulk RNA sequencing. The odontogenic differentiation (OD) potential of the cell types was determined and compared after odontogenic induction using RNA sequencing and proteomics analysis, Alizarin red staining, and alkaline phosphatase quantification.

Results: The i-MPCs demonstrated CD90⁺, CD73⁺, CD105⁺, CD13⁺, CD14^-, CD271^-, CD57^-, and CD146⁺ and their trilineage differentiation capabilities were comparable to SCAPs. The average gene expression revealed a clear distinction, with the highest expression of neural and embryonic markers in i-MPCs and odontogenic markers in SCAPs. The proteomics analysis revealed a higher baseline expression of proteins involved in OD and mineralization in SCAPs. In contrast, the differentiated cells revealed enrichment in more common pathways responsible for OD in i-MPCs. The Alizarin red staining and quantification confirmed the OD of both cell types through mineralization and calcification at 7 and 14 days. Alkaline phosphatase activity of the OD cells significantly increased on days 7 and 14 in the i-MPCs, compared to SCAPs.

Conclusions: i-MPCs and SCAPs demonstrated comparable phenotypic characteristics, with distinct transcriptomic profiles and expressions associated with their origin. Proteomics analysis of the odontogenically induced cells revealed more significant enrichment of OD pathways in i-MPCs compared to SCAPs, indicating a stronger response to differentiation cues.

Introduction: This study evaluated the accuracy and consistency of two large language models developed by Alphabet Inc., Google Gemini (GG), a base configuration, and NotebookLM (NLM), a document-grounded configuration, when answering clinical questions regarding external cervical resorption using a retrieval-augmented framework.

Methods: Forty-six dichotomous clinical questions related to external cervical resorption were developed by three academic endodontists based on established sources. Each question was submitted to GG and NLM using three independent user accounts, yielding 276 responses. The retrieval-augmented generation configuration was replicated by NLM, which was programmed to generate responses exclusively from the documents provided. Three endodontic experts independently evaluated all responses against predefined gold standard answers. Accuracy was defined as agreement with the gold standard; consistency referred to identical responses across the three trials. Statistical analyses included 95% confidence intervals (CIs) (Wald and Wilson), Fleiss' kappa, and Fisher's exact test.

Results: GG achieved an accuracy of 89% (41/46; 95% CI, 76.96-95.27) and a consistency rate of 93% (κ = 0.89; P < .001). NLM achieved an accuracy of 96% (44/46; 95% CI, 85.47-98.79) and the same consistency (κ = 0.90; P < .001). No significant differences occurred between the large language models for accuracy and consistency.

Conclusions: The NLM and GG models exhibited a high level of accuracy and consistency. Although NLM had a slightly superior performance, retrieval augmentation did not significantly enhance the responses to structured clinical tasks.

Introduction: The objective of this study was to evaluate which registration strategy (the number, configuration, and distribution range of fiducial markers) could obtain the optimal registration accuracy for guided root canal therapy.

Methods: One 3-dimensional-printed mandibular jaw model was created. The fiducial markers used for registration were prepared on the crowns of anterior and posterior teeth. The models were scanned using cone-beam computed tomography, and digital models were built. Different numbers (3, 4, 6, 8, and 10), configurations (quadrilateral, triangular, and linear) and distribution ranges (target tooth, adjacent teeth, and mandibular dentition) of fiducial markers were applied for registration of the dynamic navigation system. The target registration error (TRE) was measured. One-way analysis of variance was applied to assess registration error between groups. The significance level was set at .05.

Results: The TREs of 4 markers were significantly lower than those of three for both anterior tooth (0.32 mm vs 0.62 mm; P < .05) and posterior tooth (0.22 mm vs 1.43 mm; P < .05); increasing the number of markers to ten did not further reduce the TREs (P > .05). The TREs of markers arranged in a quadrilateral configuration were significantly lower than those in linear and triangular configurations (P < .05). The TREs of the markers selected on the target tooth and adjacent teeth were significantly lower than those in the mandibular dentition region for anterior tooth (P < .05).

Conclusions: In endodontic treatment, the best registration accuracy was obtained by selecting four spatial quadrilateral fiducial markers localized around the target tooth.