International endodontic journal最新文献

Introduction: The aim of this study was to investigate the applications of cone beam computed tomography (CBCT) amongst endodontic specialists in the United Kingdom (UK) via an online survey.

Methods: An online invitation to take part in the survey was sent out to 306 specialist endodontists registered on the UK specialist register. The survey consisted of a series of questions associated with demographics, access and use of CBCT, utilization of dose optimization parameters, and frequency of use in different clinical scenarios.

Results: In total, 202 respondents completed the survey (a response rate of 66.3%), 128 were male (63.4%), and 74 were female (36.6%). Of the 202 respondents, 174 (85.7%) used CBCT for diagnosis and/or management of endodontic problems. A CBCT scanner was on-site in 71.3% (n = 124) and 28.7% (n = 50) being off-site. A small field of view (FOV) was the prescribed scan in most cases (88.5%, n = 154/174). The cost of the CBCT scan was included in the assessment/treatment fee in 21.8% (38/174) of cases, with 78.2% (136/174) charged a separate fee for the scan. In total, 89.1% (155/174) respondents used CBCT 'often or always' for management of complex root canal anatomy, 87.4% (152/174) for root resorption, 84.5% (147/174) for periapical microsurgery, only 20.7% (36/174) of respondents would use CBCT to assess the outcome of treatment. Only 35.1% (61/174) of respondents would prescribe a CBCT scan for a pregnant patient and 78.2% (136/174) would take a CBCT scan for a paediatric patient. In total, 22.4% (39/174) of respondents did not report or request reports of their CBCT scans. Respondents chose to alter the exposure parameters depending on the patient's age or if the dentition was deemed extensively restored. Of the clinicians who incorporate CBCT into their practice, 93.7% (164/174) believe it improves the quality of the care they provide, and 93.6% (163/174) felt that the use of CBCT improves confidence in their diagnosis.

Conclusions: The use of CBCT amongst specialist endodontists in the UK is commonplace. However, usage does not appear to completely follow best practice guidance for certain clinical scenarios and highlights the need for further training in CBCT.

Aim: The aim of this study was to investigate the characteristics of vertical root fractures (VRFs) at early stages and compare them with previously reported dentinal microcracks.

Methodology: Endodontically treated teeth with vertical root fractures at early stages were collected. The characteristics of these VRFs were evaluated by in vitro observation and micro-CT scanning: (1) the number of fractures (buccal, lingual, mesial and distal were counted separately); (2) vertical extension on the roots (classified into four categories according to cemento-enamel junction and root apex involved or not); (3) the direction of fractures (bucco-lingual or mesial-distal); (4) horizontal extension of fractures (involved the root canal wall or the root surface or both); (5) the width of fractures (measured at the widest site on the axial micro-CT image); and (6) the location of the widest fractured site on the root (coronal third portion, middle third portion and apical third portion).

Results: A total of 28 vertical root fractures at early stages were collected in this study, involving 30 roots with a total of 51 fractures. All fractures involved the middle portion of root; all fractures were bucco-palatal/lingual and extended from the root canal wall to the root surface. The maximum width of these fractures were <150 μm, and widest fractures may be at the coronal, middle or apical third portion of the tooth root.

Conclusions: All vertical root fractures involved the middle portion of root, initiated from the root canal wall and directed buccal-lingually. The fractures were irregular and tortuous, with fracture widths exhibiting considerable variability. These characteristics help us to have a better understanding of the initiation and development of VRFs, and also supply evidence dentinal microcracks are an experimental phenomenon.

Stimuli-responsive hydrogels are smart and functional materials that respond to various environmental stimuli, including temperature, light, magnetic field, pH, redox, enzymes and glucose. This responsiveness allows for the controlled release of therapeutic agents encapsulated within the hydrogels, enhancing treatment precision, improving therapeutic outcomes and minimizing side effects. Such hydrogels show great potential in root canal disinfection, management of dental pulp inflammation and pulp regeneration, making them promising candidates for more personalized and effective endodontic treatments. This article provides an overview of the latest advancements in the design and application of stimuli-responsive hydrogels in endodontics, emphasizing their potential to revolutionize endodontic treatments. It also addresses current challenges and explores future directions in the field, aiming to inspire and motivate researchers to further engage in or intensify their efforts within this promising area of research.

Aim: To evaluate whether performing apical patency (AP) poses a risk for the development of osteonecrosis in rats treated with the antiresorptive drugs Zoledronic Acid (ZA) or Denosumab (DMAB).

Methodology: Forty-two male Wistar rats were divided into six groups according to the medication administered and whether apical patency was performed (n = 7): ZA, ZA-AP, DMAB, DMAB-AP, and the control groups CON and CON-AP. The ZA and ZA-AP groups received 0.125 mg/kg of ZA, while the DMAB and DMAB-AP groups received 0.25 mg/kg of DMAB, both administered via intraperitoneal injection twice a week for 4 weeks. One week after completing drug administration, endodontic access was performed on the distal occlusal fossa of the lower left first molars in all animals. AP was carried out in the distal canal of the ZA-AP, DMAB-AP, and CON-AP groups using a size 10 K-file with the aid of an electronic apex locator, extending beyond the apical foramen. In the other groups, the file was inserted up short of apex as determined by electronic apex locator measurement. Coronal sealing was performed and after 21 days, the animals were euthanized, and visual analysis, micro-CT, and histopathological assessments were conducted to evaluate the presence or absence of osteonecrosis. Statistical analysis was performed using frequency statistics and a GLM multivariate ANOVA model followed by Tukey's test with significance at p < .05.

Results: None of the animals exhibited bone exposure or other clinical signs associated with medication-related osteonecrosis of the jaw. No cortical bone destruction, periosteal reaction, or bone sequestration was observed in the micro-CT or histopathological assessments. Medication significantly influenced some micro-CT parameters (p < .05), while the apical patency alone did not (p > .05). When interacting with medication*apical patency, the ZA-AP group showed a significantly lower percentage of bone volume and bone mineral density compared to the ZA group, a tendency not observed in DMAB groups (p < .05).

Conclusions: Apical patency in rats treated with zoledronic acid or denosumab did not cause osteonecrosis of the jaw, only micro-CT changes in bone microarchitecture that cannot be linked to osteonecrosis in zoledronic acid treated animals.

Aim: Clinical and in vitro evidence indicates that chronic inflammatory responses initiated by dental caries can persist in the dental pulp even after treatment, necessitating the formation of reparative dentin to restore tissue homeostasis and health. Human dental pulp stem cells (hDPSCs) serve as crucial precursors in this reparative process. This study explores the role of B cells and their secreted factor, Angiopoietin Like 1 (ANGPTL1), in promoting hDPSCs differentiation into odontoblasts under carious conditions, with a particular focus on the activation of Forkhead box O1 (FoxO1).

Methodology: Single-cell RNA sequencing (scRNA-Seq) data from the GEO database were analysed to explore cellular interactions and molecular mechanisms in dental pulp. Immunofluorescence staining was used to investigate the expression patterns of B cells or hDPSCs in dental pulp and hydroxyapatite/tricalcium phosphate (HA/TCP) scaffolds. The expression levels of ANGPTL1 were quantified using enzyme-linked immunosorbent assay (ELISA). Odontoblast differentiation capacity was assessed by alkaline phosphatase activity, alizarin red S staining, and western blotting analysis. hDPSCs were overexpressed or knocked down FoxO1 with lentiviruses. The regulatory interaction between FoxO1 and the DSPP promoter was evaluated through dual-luciferase reporter assay and chromatin immunoprecipitation assay. Statistical analyses were conducted using Student's t-test or one-way analysis of variance (anova) with a p-value of <.05 considered statistically significant.

Results: scRNA-Seq data indicated a significant increase in B cells and ANGPTL1 expression in carious dental pulp. Functional analyses confirmed that ANGPTL1 secreted by B cells activated FoxO1 expression in hDPSCs, enhancing their differentiation into odontoblast-like cells. Blocking ANGPTL1 signalling with a specific antibody reduced FoxO1 expression, indicating a regulatory link between ANGPTL1 and FoxO1. Overexpression of FoxO1 in hDPSCs promoted their differentiation into odontoblasts and facilitated mineralized matrix formation. Mechanistic studies revealed that FoxO1 directly binds to the DSPP promoter, thereby inducing its expression.

Conclusions: Our study reveals a novel mechanism in which ANGPTL1 secreted by B cells in a carious environment promotes the odontoblast differentiation of hDPSCs by upregulating FoxO1. This finding highlights a potential therapeutic target for enhancing dental pulp repair and regeneration.

Aim: To compare the outcome of full and deep pulpotomy performed in mature permanent teeth with extremely deep carious lesion and symptomatic irreversible pulpitis.

Methodology: This parallel-group, double-blind, non-inferiority randomized controlled trial was conducted after ethical clearance. Patients with mature permanent teeth with extremely deep carious lesion and diagnosis of symptomatic irreversible pulpitis were recruited. Teeth were randomly allocated to two study groups, i.e. Group I: full pulpotomy (excision of pulp tissue up to the level of root canal orifices) and Group II: deep pulpotomy (excision of radicular pulp tissue 2-3 mm apical to root canal orifices). Haemostasis was achieved using cotton pellet moistened with 2.5% NaOCl for up to 10 min. Mineral trioxide aggregate was used as a pulp capping agent and teeth were restored in the same visit with resin composite. Outcome assessment was performed at 12-month follow-up based on clinical and radiographic evaluation. The success rate was determined by intention-to-treat (ITT) and per-protocol (PP) analysis. Two sample t-tests were used to compare the time taken to achieve haemostasis and determine its association with treatment outcome.

Results: A total of sixty teeth received treatment in both study groups. The bleeding time was significantly more in Group I (6.13 ± 1.59 min) compared to group II (5.23 ± 1.22 min) (p < .0171). The recall rate was 86.6% at study end point when fifty-two teeth were analysed at 12-month follow up. The success rate was 88.46% and 92.30% for per protocol analysis and 76.67 and 80% for ITT analysis for Group I and Group II, respectively, without any statistically significant difference (p = .610). The absolute risk difference between each treatment was within the 10% non-inferiority limit. There was no statistically significant association between time taken to achieve haemostasis and treatment outcome in both study groups.

Conclusions: There was no significant difference between full and deep pulpotomy techniques, with respect to achievement of haemostasis and treatment outcome for management of teeth with extremely deep caries and irreversible pulpitis.

Aim: Endodontic conditions are associated with severe odontogenic infections. However, no studies have explicitly explored their role in the infectious process. This study aimed to assess associations between tooth-related and patient-related factors resulting in severe odontogenic infections and clinical care needs.

Methodology: A retrospective audit was conducted of all records of patients who presented with severe odontogenic infections requiring admission between 2018 and 2023, at the largest public hospital in South Australia. Pericoronitis, postoperative, and non-odontogenic infections were excluded. Associations between tooth-related factors (type, location, presence/absence of caries, restorations, root canal filling, apical periodontitis, and space of infection), patients-related factors (diabetes and smoking statuses), clinical management (length of admission, intensive care unit admission number of days, and need for general anaesthesia) were explored. χ², Mann-Whitney's test and Fisher's exact test were used for statistical analysis, and the level of statistical significance was set at 5%.

Results: Of 382 records identified, 189 met the inclusion criteria. Mandibular (95.8%) molars (92.1%) were the most commonly offending teeth. Eight (4.2%) were root canal filled, 27 (14.3%) restored, 166 carious (87.8%), and 181 (95.8%) were associated with an apical radiolucency. Over half the sample were smokers (56.9%) and 16.4% were diabetics. The most common infection involved the submandibular space (56.1%). Intensive care unit admission was required for 157 patients (83.1%), and stay depended on the space of infection, with buccal space having the shortest duration (median 1 day) compared with submandibular (median 4 days) (p < .001). Need for general anaesthesia was associated with Ludwig's angina (n = 3, 100%) (p = .04) and submandibular space infection (n = 104, 98.1%) (p < .001), plus intensive care unit admission (p < .001). Conversely, for buccal space infection, the need for general anaesthesia was lower (n = 5, 23.8%). No further significant differences were found.

Conclusion: Untreated mandibular molars with apical periodontitis were the most frequent tooth-related findings. Results from the present study suggest associations between the most severe clinical presentations (Ludwig's angina and submandibular infection) and complexity in clinical care. Buccal space infections required the least complex management.

Aim: To develop and validate an artificial intelligence (AI)-powered tool based on convolutional neural network (CNN) for automatic segmentation of root canals in single-rooted teeth using cone-beam computed tomography (CBCT).

Methodology: A total of 69 CBCT scans were retrospectively recruited from a hospital database and acquired from two devices with varying protocols. These scans were randomly assigned to the training (n = 31, 88 teeth), validation (n = 8, 15 teeth) and testing (n = 30, 120 teeth) sets. For the training and validation data sets, each CBCT scan was imported to the Virtual Patient Creator platform, where manual segmentation of root canals was performed by two operators, establishing the ground truth. Subsequently, the AI model was tested on 30 CBCT scans (120 teeth), and the AI-generated three-dimensional (3D) virtual models were exported in standard triangle language (STL) format. Importantly, the testing data set encompassed different types of single-rooted teeth. An experienced operator evaluated the automated segmentation, and manual refinements were made to create refined 3D models (R-AI). The AI and R-AI models were compared for performance evaluation. Additionally, 30% of the testing sample was manually segmented at two different times to compare AI-based and human segmentation methods. The time taken by each segmentation method to obtain 3D models was recorded in seconds(s) for further comparison.

Results: The AI-driven tool demonstrated highly accurate segmentation of single-rooted teeth (Dice similarity coefficient [DSC] ranging from 89% to 93%; 95% Hausdorff distance [HD] ranging from 0.10 to 0.13 mm), with no significant impact of tooth type on accuracy metrics (p > .05). The AI approach outperformed the manual method (p < .05), showing higher DSC and lower 95% HD values. In terms of time efficiency, manual segmentation required significantly more time (2262.4 ± 679.1 s) compared to R-AI (94 ± 64.7 s) and AI (41.8 ± 12.2 s) methods (p < .05), representing a 54-fold decrease.

Conclusions: The novel AI-based tool exhibited highly accurate and time-efficient performance in the automatic root canal segmentation on CBCT, surpassing the human performance.

Aim: Autotransplantation of teeth (ATT) is a viable biological method for addressing dental defects. The objective was to achieve occlusal reconstruction-orientated ATT to enhance functionality and obtain optimal location and adjacency. This study proposes a new concept of a guide (a fully guided system) to achieve position-predictable ATT.

Methodology: This study included 30 transplants in 29 patients who were randomly divided into two groups during the initial examination using a single-blind method. The experimental group comprised 15 transplants in 14 patients who underwent surgery using a fully guided system. Fifteen transplants were performed on 15 patients in the control group using only a replica.

Results: The mean number of repeated teeth autotransplantation attempts and mean preparation time exhibited no significant differences. The mean follow-up period was 1 year. Twenty-six transplants were followed up clinically, while four were only followed up by phone calls. The experimental group demonstrated a 100% success rate, whereas the control group exhibited a 70% success rate, with an overall 100% survival rate. 3D analysis: Deviation of both angle and distance was calculated for evaluation of accuracy. The mean centre deviation of teeth in experiment group was 0.79 mm (95% confidence interval [CI], 0.51-1.08) compared to 1.79 mm (95% CI, 1.10-2.47) in control group (p < .05). The mean of average index points distance deviation showed a significant difference. The mean angle deviation of long axis in experiment group was 3.87° (95% CI, 2.25-5.49) compared to 12.98° (95% CI, 8.64-17.31) in control group (p < .05). The angle deviation of long axis in mesio-distal direction, buccal-lingual direction and rotation showed a significant difference also.

Conclusions: The results of the analysis indicated that the fully guided system increased the predictability of achieving an ideal transplant position with intuitive data, establishing a solid foundation for optimal dental functional recovery and restoration. However, this study had limitations regarding the generalisability of the design of the optimal location for transplantation and the equipment requirements for clinical procedures. Therefore, further research on the screening of indications for guided systems and location planning is necessary.

Clinical trial registration: This study was registered on the Chinese Clinical Trial Registry (Registration Number: ChiCTR 2300074646).

Background: Circadian rhythm disruption (CRD) affects the expression levels of a range of biological clock genes, such as brain and muscle ARNT-Like-1 (BMAL1), which is considered to be an important factor in triggering or exacerbating inflammatory response. However, the underlying effect of CRD on the pathogenesis of apical periodontitis, a common oral inflammatory disease, currently remains unknown. Exploring the effects and pathogenic mechanisms of CRD on apical periodontitis will be beneficial in providing new ideas for the prevention and treatment of apical periodontitis.

Methodology: The cross-sectional study was conducted among patients with apical periodontitis visiting to hospital. Rat models combining CRD and apical periodontitis were constructed, and the destruction of periapical alveolar bone was assessed by Micro-CT, H&E, and TRAP staining assay. Rat periapical alveolar bone tissues were collected for RT-qPCR and immunohistochemistry to further detect the expression of periapical biological clock genes. A model of apical periodontitis was constructed using Bmal1^-/- and WT rats to further verify the key role played by Bmal1. Finally, rats raised in CRD environment were intraperitoneally injected with melatonin to restore the circadian rhythm, and the periapical alveolar bone repair was observed by Masson's staining and staining of osteogenic markers (ALP, RUNX2).

Results: A close association between CRD and acute exacerbation of chronic apical periodontitis (CAP) in patients was first found in an epidemiological survey. By constructing animal models of CRD and apical periodontitis, it was found that CRD could aggravate the inflammatory stress of apical periodontitis and even drive the acute exacerbation of CAP. Further investigations suggested that the expression of crucial clock genes, especially Bmal1, were significantly disrupted in the periapical tissue of apical periodontitis. In addition, the periapical tissue from Bmal1 knockout rat displayed stronger inflammatory response and more severe alveolar bone destruction in apical periodontitis. Restoring circadian rhythm by melatonin supplementation could effectively alleviate both the inflammatory response and alveolar bone loss in apical periodontitis.

Conclusion: CRD is a novel trigger in aggravating the inflammatory response and alveolar bone loss of apical periodontitis. Melatonin is expected to be used in the dental clinic as an important adjunctive therapy strategy for the healing of periapical tissue in apical periodontitis.