Human dental pulp stem cells (hDPSCs) have increasingly gained interest as a potential therapy for nerve regeneration in medicine and dentistry, however their neurogenic potential remains a matter of debate. This study aimed to characterize hDPSC neuronal differentiation in comparison with the human SH-SY5Y neuronal stem cell differentiation model. Both hDPSCs and SH-SY5Y could be differentiated to generate typical neuronal-like cells following sequential treatment with all-trans retinoic acid (ATRA) and brain-derived neurotrophic factor (BDNF), as evidenced by significant expression of neuronal proteins βIII-tubulin (TUBB3) and neurofilament medium (NF-M). Both cell types also expressed multiple neural gene markers including growth-associated protein 43 (GAP43), enolase 2/neuron-specific enolase (ENO2/NSE), synapsin I (SYN1), nestin (NES), and peripherin (PRPH), and exhibited measurable voltage-activated Na⁺ and K⁺ currents. In hDPSCs, upregulation of acetylcholinesterase (ACHE), choline O-acetyltransferase (CHAT), sodium channel alpha subunit 9 (SCN9A), POU class 4 homeobox 1 (POU4F1/BRN3A) along with a downregulation of motor neuron and pancreas homeobox 1 (MNX1) indicated that differentiation was more guided toward a cholinergic sensory neuronal lineage. Furthermore, the Extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor U0126 significantly impaired hDPSC neuronal differentiation and was associated with reduction of the ERK1/2 phosphorylation. In conclusion, this study demonstrates that extracellular signal-regulated kinase/Mitogen-activated protein kinase (ERK/MAPK) is necessary for sensory cholinergic neuronal differentiation of hDPSCs. hDPSC-derived cholinergic sensory neuronal-like cells represent a novel model and potential source for neuronal regeneration therapies.

Recent literature has suggested a potential association between inflammatory bowel diseases (IBD) and apical periodontitis (AP). The present systematic review and meta-analysis sought to analyse and appraise the available evidence regarding the reported association. Following 2020 PRISMA guidelines, a comprehensive search of multiple online databases (PubMed, Scopus, Web of Science, and Google Scholar) was conducted for all relevant studies published from the date of inception until 27 April 2023 using various relevant keywords. All observational studies that assessed the association between IBD and AP in humans were eligible for inclusion. The quality of the selected studies was carried out independently by two reviewers, and meta-analysis was performed using Comprehensive Meta-Analysis Version 2.2.064. Six studies (five case-control studies and one cohort study) were included. A total of 657 patients (277 with IBD) were included in 5 case-control studies, and 48,223 subjects (35,740 with AP) were included in the cohort study, where 188 developed IBD on follow-up. The pooled data from the five case-control studies revealed that IBD was significantly associated with a higher risk of AP (OR=1.71, 95% CI: 1.21–2.42; I2=10.337%, fixed-effect, p=0.002). The qualitative analysis also showed that most of the included studies found a higher mean number of teeth with AP in IBD groups than the healthy controls. Newcastle-Ottawa Scale (NOS)-based quality appraisal results demonstrated that five studies were of high quality, and one was of moderate quality. The results suggest a potential association between IBD and AP. Large-scale and prospective studies are required to further confirm and elucidate the nature of such an association. (EEJ-2023-05-057)

Background: Low‐intensity pulsed ultrasound (LIPUS) has been highlighted as a potential therapy for tissue repair and regeneration. However, little is known about LIPUS effects on neuromodulation. This research was conducted to study LIPUS effect on the proliferation of human neural stem cells.Materials and methods: The human SH‐SY5Y neuroblastoma cell line was used as a neural stem cell model. The well‐documented SH‐SY5Y neurogenic protocol, which involves treatment with all trans‐retinoic acid (ATRA) for 5 days and then brain‐derived neurotrophic factor (BDNF) for 7 days, was used to synchronise the growth cell cycle to G1 phase of the cell cycle before proliferation testing. Subsequently, the neural stem cells were then treated with single or triple 20‐min LIPUS exposures (Intensity I_SATA: 60 mW/cm², frequency: 1.5 MHz, pulse repetition: 100 Hz, and duty cycle: 20%). Cell proliferation was analysed using cell counting of β‐tubulin and neurofilament medium‐positive neural stem cells, Ki67‐cell proliferation marker and metabolic‐based assays (cell counting kit‐8 and alamarBlue). The involvement of ERK signalling was investigated by quantification of phospho‐ERK1/2 levels and cell proliferation with and without MEK/ERK inhibitor (U0126).Results: The results show that LIPUS exposure(s) induced cell proliferation, as evidenced by an increase in the numbers of neural stem cells. ERK signalling is involved in LIPUS‐induced neural stem cell proliferation, as evidenced by concurrent inhibition of LIPUS‐induced phospho‐ERK levels and cell proliferation in the presence of the MEK/ERK inhibitor.Conclusion: This study provides original evidence that LIPUS can stimulate neural stem/progenitor cell proliferation. LIPUS may be suggested as a sole or an adjunct therapeutic application to promote the neural stem cell pool in stem cell therapies and tissue engineering approaches for nerve repair and regeneration for the management of traumatic nerve injuries and regenerative endodontic treatment.

Background: This cone beam computed tomography (CBCT) endodontics study aimed to compare the canal-centering ability and canal transportation of Edgefile X7 and HyFlex EDM files in moderately curved mesiobuccal (MB) root canals of 30 mandibular first permanent molar teeth. Material/Methods: Thirty permanent mandibular first molars with 10 degrees and 24 degrees of mesial root curvature were selected and scanned with CBCT. Two experimental groups of 15 each were made: group I: HyFlex EDM, and group II: Edgefile X7. The MB canals were instrumented, and CBCT scans were repeated. The distance from MB canal to the outer wall of the root was measured on pre- and post-instrumentation scans at 3 mm, 6 mm, and 9 mm from the apex. Canal transportation and centering ability were determined using established calculation methods. Results: For HyFlex EDM, average canal transportation was 0.01 +/- 0.17 mm,-0.10 +/- 0.21 mm, and 0.03 +/- 0.33 mm at 3 mm, 6 mm, and 9 mm, respectively; for Edgefile X7, average canal transportation was-0.02 +/- 0.21 mm, 0.07 +/- 0.22 mm, and-0.12 +/- 0.23 mm, respectively. HyFlex EDM group showed considerable canal transportation at 6 mm (P<0.05), while both groups showed non-significant differences at 3 mm and 9 mm. Conclusions: At levels of 3 mm, 6 mm, and 9 mm, canal transportation was observed either on the mesial or distal surface of the canal curvature by HyFlex EDM and Edgefile X7 file systems. Compared with the HyFlex EDM file system, the Edgefile X7 file system showed reduced canal transportation and improved canal-centering ability.

Background: The bioactive molecules released from dentine are key to stem‐cell recruitment, proliferation and differentiation in regenerative endodontics. However, there is limited and conflicting information regarding current and potential agents for releasing dentine bioactive molecules for regenerative endodontic procedures. Objectives: To answer a focused and PICOS‐designed question: are there any available experimental agents [Intervention (I)] comparable to EDTA [Comparison/Control (C)] in releasing bioactive molecules [Outcome (O)] from dentine [Population (P)] for regenerative endodontic procedures? Method: A systematic search was conducted (PubMed, Web of Science, Scopus, Medline [Ovid], Embase [Ovid], ProQuest Central, Google Scholar and citation searching: backwards and forwards), from inception until August 2025. The selection process followed the PICOS model to define inclusion and exclusion criteria. Original studies investigating experimental agents for the release of bioactive molecules from the dentine, compared with EDTA, were included. The risk of bias was strictly assessed using the QUIN tool for in vitro dental studies. Qualitative analysis was performed, while meta‐analysis was not possible. Results: Out of the 1364 studies screened, 32 were included. These studies from 2000 to 2025 investigated 23 experimental agents in comparison with EDTA. All were in vitro; of the studies, two had a low risk of bias, 25 had a moderate risk (11 with the minimum score) and five had a high risk of bias. A lack of methodological rigour was identified in approximately 80% of the included studies, including omissions of pH measurements for experimental groups, deficiencies in data assessment or normalisation to account for potential inter‐sample variability and deficiencies in validation against detection limits. The qualitative analysis indicated that 9% etidronic acid (known as HEBP), 1% phytic acid, chitosan and 10% citric acid released TGF‐β1 and/or VEGF levels as effectively as both 10% and 17% EDTA. Conclusion: Qualitative analysis suggested that 9% etidronic acid (HEBP), 1% phytic acid, chitosan and 10% citric acid might serve as alternatives to 17% EDTA use for releasing bioactive molecules from dentine. However, the methodological issues and lack of robust evidence limit the strength and comparability of the findings, highlighting the need for further well‐designed and rigorous studies before clinical translation. Registration: Open Science Framework (OSF) registries: 10.17605/OSF.IO/SPDUQ (Registration DOI: https://doi.org/10.17605/OSF.IO/SPDUQ )