Journal of endodontics最新文献

Autogenous tooth transplantation (ATT) using open-apex donor teeth may preserve pulp vitality, but atraumatic retrieval of impacted third molars is challenging. This case report describes an interdisciplinary workflow combining orthodontic donor activation with digitally guided, vitality-preserving ATT. A 27-year-old woman with an edentulous maxillary left first molar site (tooth #14) underwent ATT using an immature mandibular right third molar (tooth #32) as the donor. After 6 weeks of orthodontic traction, cone-beam computed tomography and intraoral scans were registered for virtual planning and fabrication of a 3-dimensional-printed donor replica and trephine-compatible osteotomy and seating guides. The recipient site was prepared under trephine guidance, platelet-rich fibrin was applied, and the transplant was stabilized with splinting. Clinical and radiographic follow-up was performed for 24 months. Radiographs showed progressive trabecular fill and stable crestal bone through 18 months. At 24 months, the transplant was functional and responded to sensibility testing (electric pulp test: #14, 69; control tooth #3, 26). Cone-beam computed tomography demonstrated near-complete apical closure, stable alveolar bone, and donor-site bone regeneration (1310.53 mm³), with no evidence of external root resorption or ankylosis. Orthodontic activation combined with guide-assisted preparation may facilitate vitality preserving ATT using an open-apex third molar in a posterior maxillary site.

Introduction: To investigate the influence of different types of intracanal medicaments and root canal sealers on root dentine fracture resistance at different time intervals.

Methods: A total of 180 single-rooted human mandibular premolars were used. Samples were divided into 3 groups: negative control (unprepared and unfilled, n = 10), positive control (prepared but unfilled, n = 10), and experimental groups (10 groups, n = 15). Root canals were prepared chemomechanically. In single-visit groups, canals were filled with either AH Plus or Bio-C Sealer. In medicament-applied groups, Ultracal XS or Bio-C Temp was applied for 1 week or 1 month before obturation with AH Plus or Bio-C Sealer. Root dentine fracture resistance was measured under vertical loading using a universal testing machine. Material-dentine interface of 10 experimental samples were examined using scanning electron microscope/energy dispersive x-ray spectroscopy. Data were analyzed using the analysis of variance followed by post hoc Tukey's tests, with significance set at P < .05.

Results: Root dentine fracture resistance was highest in the negative control and lowest in the positive control (P < .001). Single-visit groups demonstrated significantly higher root dentine fracture resistance than the medicament-applied groups (P < .001). No significant differences were found in the single-visit AH Plus and Bio-C Sealer (P > .05). Similarly, no significant difference was observed between the groups filled with AH Plus or Bio-C Sealer after application of Ultracal XS or Bio-C Temp (P > .05). Furthermore, the time of medicament application (1 week-1 month) was found to have no significant effect on root dentine fracture resistance (P > .05).

Conclusions: Different intracanal medicaments (Ultracal XS, Bio-C Temp) and root canal sealers (AH Plus, Bio-C Sealer) exhibited similar effects on root dentine fracture resistance at different time intervals. However, both Ultracal XS and Bio-C Temp may adversely affect root dentine fracture resistance due to their tendency to leave residues on the dentine surface.

Introduction: This study employed metatranscriptomics to investigate the endodontic microbiome and resistome in acute apical abscesses (AAA) and asymptomatic apical periodontitis (AAP).

Methods: Root canal samples were collected from 20 patients, including 10 cases of AAA and 10 cases of AAP. RNA sequencing was conducted using the NovaSeq 6000 system. Taxonomic analysis utilized the expanded Human Oral Microbiome Database (eHOMD) database and functional annotation was executed using the DIAMOND and EGGNOG databases. Resistome analysis was conducted with the Comprehensive Antibiotic Resistance Database (CARD) and BacMet - Antibacterial Biocide and Metal Resistance Database. Differential expression analysis was carried out using DESeq2 from the DESeq2 R package (P < .05).

Results: Taxonomic analysis showed more gram-negative species in AAA samples (P < .05), particularly from the Bacteroidota phylum. In functional analysis, Tannerella forsythia and Streptococcus anginosus group (SAG) showed the highest transcriptional activity in AAA. T. forsythia displayed high expression of Rag/SusD proteins, suggesting a potential virulence mechanism. The main protein family found in both conditions was the adenosine triphosphate-binding cassette (ABC) transporter. Transcripts possibly involved in resistance against various antibiotics (cephalosporins, fluoroquinolones, lincosamides, macrolides, tetracyclines), metals (silver, chromium, zinc), and disinfectants (phenolic compounds, acids, and bases) were identified.

Conclusions: T. forsythia and SAG demonstrated high activity within the root canal microbiome in cases of AAA, suggesting their involvement in the pathogenicity of the community associated with acute infections. The ABC transporter may play a significant role in antimicrobial resistance through an antibiotic efflux mechanism and contribute to tolerance against disinfectants and antiseptics.

Introduction: The GentleWave System, based on multisonic ultra-cleaning technology, has been proposed as an irrigation approach capable of enhancing disinfection while preserving dentin structure. However, evidence regarding its comparative efficacy and clinical relevance remains inconsistent. This scoping review aimed to comprehensively evaluate the performance of the GentleWave System in comparison with conventional syringe irrigation and other activation techniques.

Methods: This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. Six electronic databases (PubMed, Scopus, Web of Science, Embase, Cochrane Library, and Google Scholar) were systematically searched without language restrictions. Studies were eligible if they compared GentleWave with at least one other irrigation or activation technique and reported measurable outcomes. In vitro, ex vivo, and clinical studies were included. Study characteristics, irrigation protocols, outcomes, and key findings were extracted and synthesized descriptively across thematic domains.

Results: Twenty-two studies met the inclusion criteria. Laboratory evidence demonstrated that GentleWave enhanced debris removal, irrigant penetration, and calcium hydroxide removal compared to conventional syringe irrigation. However, several studies have reported no significant differences between GentleWave and ultrasonic or sonic activation in terms of smear layer removal, biofilm reduction, or removal of filling materials. Findings related to endotoxin reduction and disinfection were also heterogeneous. Clinical evidence was limited and generally indicated no differences in postoperative pain or early healing when compared with alternative techniques.

Conclusions: The present scoping review indicates that the GentleWave System demonstrates promising performance across multiple laboratory outcomes, particularly in debris removal, disinfection, and irrigant penetration. However, the available evidence remains inconsistent, with several well-designed studies reporting no significant differences between GentleWave and established irrigation or activation techniques.

Introduction: Cyclic fatigue failure is an inherent feature of rotary files when used in curved canals. This study aimed to assess the effect of repeated usage and autoclave sterilization on the dynamic cyclic fatigue resistance of heat-treated nickel-titanium files used to prepare J-shaped canals.

Methods: New ProTaper Ultimate nickel-titanium files (Slider, Shaper, F1, F2) (n = 180) were divided into 3 groups (n = 60): Group N, included new files, were groups US-2 and US-4 included files subjected to 2 or 4 cycles of usage and sterilization, respectively. Files were used to prepare a resin-simulated J-shaped canal (19 mm length, 30° curvature) at 37°C. After each use, files were sterilized in an autoclave at 134°C for 25 minutes. Dynamic cyclic fatigue testing was then performed at 37°C, and the mean number of cycles to failure (NCF) was recorded. Fractured fragment lengths were measured using a digital microcaliper. Statistical analysis was performed using one-way ANOVA and the Kruskal-Wallis test. A P-value <.05 was considered significant.

Results: The Slider file consistently showed significantly higher NCF values than Shaper, F1, and F2 files in all the groups (P < .05). Repeated cycles of usage/sterilizations had an adverse effect on the cyclic fatigue resistance of all files, with a marked reduction after 4 uses.

Conclusions: Repeated usage and autoclave sterilization showed a marked adverse effect on the novel heat-treated files. A positive correlation was seen between the increased number of usage and autoclave cycles and the reduction in NCF.

Introduction: Advanced irrigation plays a crucial role in nonsurgical retreatment cases, as these procedures require the removal of existing obturation materials while preserving dentin. The aim of this study was to compare the effectiveness of laser-activated versus sonic-activated irrigation in removing residual obturation material in the mesial canals of mandibular molars with isthmuses during nonsurgical root canal retreatment.

Methods: Forty mesial canals of extracted mandibular molars were instrumented and obturated with gutta-percha and a bioceramic sealer. Retretments was performed using rotary instruments, followed by a final irrigation protocol consisting of 2.5% NaOCl, 17% EDTA, and a final rinse of 2.5% NaOCl using either sonic-activated or laser-activated irrigation (LAI). Micro-computed tomography scans were obtained before and after final irrigation. The volume of obturation material was measured to calculate the median percentage of remaining material in each group.

Results: The LAI group showed a significantly lower median percentage of remaining filling material than the sonic group (73.9% vs. 93.8%, P = .0165). However, neither irrigation protocol completely eliminates residual obturation material from the canals.

Conclusion: LAI was more effective at removing remaining obturation material compared to sonic-activated irrigation.

Introduction: In early stages of cracked teeth, pulpal inflammation is considered reversible. Cracked teeth with retained pulp vitality demonstrate higher survival rates whereas root canal treatment (RCT) negatively influences survival outcomes. The clinical challenge lies in discerning when RCT is required. This study aimed to develop and validate machine learning (ML) models for predicting pulp survival in cracked teeth with reversible pulpitis and investigating associations between patient- and tooth-related variables and treatment outcomes.

Methods: Data from 569 patients with 593 cracked teeth were analyzed using Logistic Regression, Gaussian Processes, Random Forests and Gradient Boosting. Input features included age, gender, tooth type and preoperative restorative material. The binary outcome represented pulp survival. A 10-fold stratified nested cross-validation approach was used: the outer loop estimated model performance and the inner loop optimized hyperparameters. Classification thresholds were tuned for probabilistic models. Performance metrics included AUC, F1-score, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

Results: Logistic Regression achieved the highest AUC (0.64) and F1-score (0.60), with strong PPV (0.76) and moderate NPV (0.48), indicating effective identification of patients requiring RCT. Other models showed similar but slightly lower performance (PPV: 0.74-0.77; NPV: 0.45-0.47). Significant predictors of pulp survival included age and presence of preoperative restorations. Older patients and those with existing restorations were less likely to require RCT.

Conclusion: ML models demonstrated a predictive accuracy of 74-77%. They could improve diagnostic precision and support timely decision-making for endodontic intervention in the management of cracked teeth with reversible pulpitis.

Introduction: This study assesses whether variations to cone-beam computed tomography (CBCT) slice thickness (ST) effect the detection accuracy and volume assessment of periapical lesions.

Methods: Forty periapical lesions were assessed on CBCT reconstructions with 0.125-mm, 0.25-mm, 0.50-mm, 1.00-mm, 1.50-mm, and 2.00-mm ST. Mimics Research was used to perform the semi-automatic segmentation technique to determine periapical lesion volume and CBCT periapical volume index (CBCTPAVI) score on each CBCT reconstruction. Diagnostic accuracy was assessed by determining the percentage of lesions detected on each reconstruction, and the Friedman test was conducted to assess for significant differences in lesion volume between the different CBCT reconstructions. Differences among CBCTPAVI scores were also assessed.

Results: Periapical lesion volume was significantly underestimated on CBCT reconstructions with ST above 1.00 mm. Variations in periapical lesion volume were the greatest among smaller lesions resulting in false negative diagnoses with the utilization of CBCTs with ST above 0.50 mm.

Conclusions: Variations in CBCT ST can significantly influence measured periapical lesion volume, and failure to account for this may lead to misinterpretation of lesion progression or healing. A minimum ST of 0.50 mm was required for the reliable detection of all periapical lesions, and this threshold serves as a benchmark for optimizing CBCT acquisition protocols to preserve diagnostic accuracy while minimizing radiation exposure.

Introduction: There is a need for safe and potent antibiofilm agents for root canal irrigation. The aim of this study was to investigate the antibiofilm activity of enzymatic irrigants (Bromelain and Papain) and their cytocompatibility to mammalian cells.

Methods: Biofilms of Enterococcus faecalis were developed on dentin discs and treated with 0.05% bromelain, 4% papain, 2.5% sodium hypochlorite (NaOCl) or saline for 15 min. The antibiofilm effectiveness was characterized by quantifying the colony forming units (CFU) and confocal microscopic examination of the bacterial cells (live/dead staining) and extracellular matrix polysaccharide using a selective fluorophore binding assay. Cytotoxicity of 0.05% bromelain, 4% papain and 2.5% NaOCl to human periodontal ligament fibroblasts was investigated using a metabolic activity assay. Data were analyzed using analysis of variance and nonparametric tests, with significance set at P < .05.

Results: Papain (4%) and Bromelain (0.05%) demonstrated 5 log CFU reduction, which was comparable to 2.5% NaOCl (P > .05). Confocal microscopy further confirmed that bromelain, sodium hypochlorite, and papain caused significantly greater bacterial cell death compared to saline (P < .05). Papain significantly reduced the extracellular matrix polysaccharide content within the biofilm compared to all other groups (P < .05).

Conclusion: This study demonstrated that bromelain and papain showed comparable antibiofilm activity as 2.5% NaOCl and were more biocompatible than NaOCl, highlighting their potential to be developed as root canal irrigants.

This case report describes the extraction of 3 mandibular posterior teeth (teeth #19, 20 and 21) with extensive invasive external cervical resorption (ECR) followed by guided double auto-transplantation of immature mandibular third molars (teeth #17 and 32). A 17-year-old male with a history of orthodontic treatment reported with intermittent pain in the mandibular left posterior region. Clinical and radiographic examination revealed extensive tooth tissue loss in teeth #19, 20 and 21 that was diagnosed as class 3 ECR (Patel 3Dp for teeth #20 and 21, 3Bp for tooth #19). Guided double auto-transplantation of the immature molar tooth #17 was performed to replace premolar teeth 20 and 21, and tooth #32 to replace tooth #19. At the 6-month follow-up the donor tooth #32 had symptoms of pulpitis and was managed with a full pulpotomy using tricalcium silicate cement. Both teeth were followed-up for 36 months when they were asymptomatic, had no associated periodontal defects, had positive pulp sensibility tests as well as radiographic evidence of substantial periapical bony healing. The roots of tooth #17 had only a limited increase in length, with apical hard tissue barrier deposition, whereas tooth #32 (after pulpotomy) had continued root development. The 36 months follow-up of this case highlights the success of an interdisciplinary approach when integrating three-dimensional guides for double auto-transplantation of immature molars to successfully replace multiple teeth with extensive invasive ECR.