International endodontic journal最新文献

Aim: Dens invaginatus (DI) is a developmental anomaly often associated with caries and periapical pathosis. This report describes guided access and filling of an infected invagination in a maxillary lateral (tooth #22) with long-term preservation of pulp vitality.

Summary: A 9-year-old male presented with a palatal sinus tract associated with immature tooth 22. Based on clinical and radiographic examination, a type IIIa DI with a pseudo-foramen midway along the mesial aspect of the root was identified. The tooth had a healthy pulp and peri-invagination periodontitis. A guided endodontic cavity was prepared to selectively access the invagination without compromising the pulp and the invagination filled with a bioceramic calcium silicate-based material. At 36 months the tooth was asymptomatic, and the pulp tested positive. Radiographically, root development was complete with bony healing of the lesion. This case report highlights the effectiveness of guided cavity preparation to access an invagination in an immature tooth with DI while preserving pulp vitality.

Aim: Biomaterial-based strategies offer therapeutic potential for inherited disorders such as Dentinogenesis imperfecta type II (DGI-II). DGI-II, a hereditary dental disorder caused by dentine sialophosphoprotein (Dspp) gene mutations, results in fragile, discoloured teeth susceptible to wear and decay. This study investigates the structural alterations in the dentine matrix induced by mutant DSPP and the underlying molecular mechanisms. Furthermore, we evaluated a therapeutic strategy combining nanofibrous substrates with molecular activation of the Wnt5a-Cdc42 pathway, aiming to mitigate these structural defects and restore dentine integrity.

Methodology: A maxillary first premolar extracted from a patient with dentinogenesis imperfecta type II (DGI-II) carrying a known DSPP frameshift mutation was analysed using micro-computed tomography and scanning electron microscopy. MDPC-23 mouse dental pulp pre-odontoblasts were cultured in vitro on electrospun nanofibrous scaffolds with tunable fibre diameters. Dspp expression was silenced to investigate its regulatory role in cell-cell contact formation, while the Wnt5a-Cdc42 pathway was activated via recombinant Wnt5a protein and a small molecule. Data were analysed using Student's t-test or one-way ANOVA with a significance threshold of p < 0.05.

Results: Decalcified or freeze-fractured samples exhibited thick fibres, sparse dentinal tubules, and a disorganised, non-layered dentine matrix, indicating that disrupted cell-cell junctions impair directional appositional dentine formation. Silencing Dspp expression in dental pulp cells led to reduced expression of junctional proteins, Zona occludens-1 (ZO-1) and Connexin43 (Cx43), which are essential for vectorial matrix apposition. Modulating fibre thickness and activating the Wnt5a-Cdc42 signalling axis restored both the expression and cellular localisation of ZO-1 and Cx43, thereby re-establishing cell-cell junctions and paracellular permeability in Dspp-silenced dental pulp cells.

Conclusion: The results provide evidence that Dspp contributes to the structural integrity of dentine by modulating ZO-1 and Cx43 expression and suggest that biomaterial and molecular interventions may offer supportive strategies to restore dentine structure and function in DGI-affected teeth, though they do not address the underlying genetic defect.

Aim: This in vitro study evaluated the feasibility, precision and efficiency of robot-assisted tooth autotransplantation compared with static template-guided and freehand techniques.

Methodology: A total of 120 mandibular resin-bone models were randomly assigned to robot-assisted (RA), template-guided (TG) or freehand (FH) socket preparation (n = 40 each). Preoperative CBCT and intraoral scans were merged for virtual planning. In RA, a Yakebot integrated autonomous drilling and dynamic navigation. Accuracy and efficiency were assessed by 10 metrics (CDD, IPDD-C, IPDD-R, LAD, MDAD, BLAD, RAD, Hausdorff distance, Dice coefficient and socket preparation time). Statistical analyses were performed using the Kruskal-Wallis test followed by Dunn's post hoc tests with Bonferroni correction.

Results: RA achieved the smallest deviations across all parameters. Mean CDD was 0.49 ± 0.25 mm in RA, significantly lower than TG (0.63 ± 0.22 mm) and FH (0.69 ± 0.33 mm; p = 0.005). RA also showed the lowest angular errors (LAD 3.81° vs. TG 6.10° and FH 9.54°; p < 0.001) and highest reproducibility. Hausdorff and Dice analyses confirmed superior 3D congruence in RA. Mean socket preparation time was shortest in RA (5.59 ± 0.32 min; p < 0.001).

Conclusion: Under standardised in vitro conditions, robot-assisted autotransplantation achieved higher preparation accuracy, reproducibility and procedural efficiency than template-guided and freehand methods. By integrating robot-guided drilling with dynamic navigation, the system enabled precise socket preparation and may help reduce the technical demands of the procedure. These findings provide preliminary evidence of feasibility and support further validation in clinical studies.

Aim: Irreversible pulpitis poses a significant clinical burden due to progressive inflammatory pulp damage. While inflammatory mechanisms are central to its pathogenesis, they remain incompletely characterised. This study aims to elucidate the role of Nod-like receptor thermal domain associated protein 1 (NLRP1) in irreversible pulpitis pathogenesis.

Methodology: Transcriptomic analysis of public dataset GSE77459 identified dysregulated pyroptosis-related genes (PRGs), with machine learning prioritising hub genes for experimental validation. Key targets were experimentally verified through an integrated approach: in vitro models using lipopolysaccharide (LPS)-stimulated human dental pulp cells (hDPCs) analysed by qRT-PCR, ELISA and Western blot and specific pyroptosis assays (PI uptake, Caspase-1 cleavage); in vivo rat pulpitis models; and clinically validation with human irreversible pulpitis tissues analysed via H&E staining, immunohistochemistry (IHC) and immunofluorescence (IF). Functional roles were further assessed via NLRP1 knockdown and overexpression in hDPCs.

Results: Bioinformatics identified 11 differentially expressed PRGs, with machine learning highlighting six hub genes including unreported NLRP1. Specific pyroptosis assays confirmed that LPS induces membrane pore formation and Caspase-1 activation in hDPCs. Significant post-transcriptional regulation of NLRP1 was demonstrated by pronounced protein upregulation in LPS-stimulated hDPCs despite unaltered mRNA. Functional studies established NLRP1 as a positive regulator, where its knockdown attenuated the LPS-induced inflammatory-pyroptotic response, while its overexpression alone was sufficient to upregulate key mediators. Consistently, elevated NLRP1 expression was observed in rat models and human tissues, where IHC/IF localised prominent expression to inflammatory infiltrates.

Conclusion: NLRP1 is highlighted as a novel pyroptosis biomarker for irreversible pulpitis, with its dysregulation offering diagnostic value for inflammation. These findings suggest its potential involvement in the inflammatory mechanisms of pulpitis, providing a new molecular target for future therapeutic exploration.

Background: In general medicine, melatonin is known to enhance wound healing and promote stem cell differentiation. Its potential relevance in endodontics, however, remains underexplored.

Objectives: This scoping review aimed to systematically assess the available evidence on the effects of melatonin (a) on dental pulp tissue and (b) on human dental pulp stem cells (hDPSCs), particularly regarding cell proliferation and differentiation with regard to endodontics.

Methodology: A comprehensive literature search was conducted in PubMed, Clarivate Analytics' Web of Science and Scopus from inception to July 1, 2025, using Medical Subject Headings (MeSH terms) and supplemented by hand searching and screening of major subject journals.

Results: The initial search yielded 252 records, with one additional record identified through citation mining and relevant journal screening. A total of 22 studies met the inclusion criteria: 11 investigated melatonin's effect on dental pulp tissue regarding anti-inflammatory properties, treatment of pulpitis, wound healing and pulp capping and 11 examined its impact on hDPSCs in terms of cell proliferation and differentiation.

Discussion: The limited evidence obtained from laboratory and animal studies suggests a dose- and time-dependent influence of melatonin, though evidence is insufficient to establish optimal concentrations.

Conclusions: (a) Melatonin demonstrates anti-inflammatory, antioxidant and anti-fibrinolytic effects on dental pulp tissue. (b) Melatonin has potential as a stem cell modulator by promoting odontogenic differentiation and may improve migration and proliferation of hDPSCs.

Background: Cell-based regenerative endodontic procedures (REPs) using dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHEDs) and those from apical papillae have shown great potential for authentic pulp regeneration, as evidenced by reports from preclinical studies and limited clinical trials. However, challenges, such as low cell survival rates, immune rejection during allogeneic transplantation and inconsistent protocols, hinder their widespread clinical implementation.

Objectives: This review aimed to summarise the regenerative methodologies widely used in studies involving autologous and allogenic DPSC/SHED transplantation and their clinical outcomes, analyse the discrepancies between preclinical and clinical studies, explore the potential mechanisms underlying alloimmune responses in allogeneic cell transplantation and provide possible strategies to minimise this type of immune rejection.

Methods: A comprehensive search was conducted on clinicaltrials.gov using keywords '(dental pulp stem cells) OR (dental pulp mesenchymal cells) OR (DPSCs) OR (human deciduous teeth stem cells) OR (stem cells from human exfoliated teeth) OR (SHED),' followed by inputting keywords '(NestaCell) OR (Cellavita HD).' Clinical trials not registered on the website and case reports were also included via advanced search on PubMed using keywords '(dental pulp stem cells) OR (dental pulp mesenchymal cells) OR (DPSCs) OR (human deciduous teeth stem cells) OR (stem cells from human exfoliated teeth) OR (SHED)' with filters '(Case reports) AND (Clinical trial).'

Results: Twenty-seven clinical trials and 11 case reports were included. Whereas these studies related to endodontic diseases revealed favourable outcomes for teeth treated with pulp regeneration approaches, preclinical studies observed limited cell survival in vivo, indicating that DPSCs exhibit environment-dependent immunogenicity and immunoregulatory properties under favourable conditions but become immunogenic in stressful microenvironments such as cell passage and differentiation, hypoxia and inflammation. Potential strategies have been developed to prolong DPSC survival.

Conclusions: Despite encouraging preliminary results, significant limitations remain in the establishment of standardised protocols and the development of reliable techniques for longitudinal cell tracking. In future research, optimised delivery systems, immune-evasive cell engineering and rigorous clinical trial designs should be optimised to advance REPs towards predictable, clinically viable therapies.

Introduction: Accessory canals (ACs) are anatomical features that may harbour residual infected tissue and contribute to persistent periradicular inflammation. Although filling of these structures is occasionally achieved passively, their intentional mechanical negotiation remains rarely documented in clinical practice. This case series aims to describe the clinical approach, outcomes and imaging strategies used in the intentional debridement and filling of ACs.

Methods: Six teeth with identifiable ACs on cone-beam computed tomography (CBCT), in association with bone resorption, were included. All cases underwent chemomechanical preparation using rotary instrumentation with 2% chlorhexidine gel, active saline irrigation and final EDTA activation with passive ultrasonic irrigation. Intentional mechanical debridement of ACs was performed using small-diameter hand files. All fillings were performed with gutta-percha and AH Plus Jet sealer. Follow-up was performed using CBCT and periapical radiographs after a mean period of 10.16 months. Three-dimensional segmentation was used to aid localization and planning.

Results: All ACs were successfully negotiated and filled with endodontic sealer. Tomographic analysis confirmed evidence of partial or complete periradicular healing in all six cases. No patients presented with clinical symptoms at follow-up.

Conclusion: This case series presents successful intentional instrumentation and obturation of ACs, supported by CBCT-based planning and follow-up. Although limited by the lack of a control group, the findings highlight the potential role of CBCT imaging and segmentation in identifying and accessing complex anatomy. Further prospective studies are needed to determine the impact of this approach on long-term clinical outcomes.