This study aimed to evaluate the overall treatment outcomes of direct pulp capping in permanent teeth and investigate the prognostic factors. MEDLINE via Ovid, EMBASE, PubMed, Cochrane Library, and manual search methods were used to select the included studies. After thorough screening, the criteria for quality assessment and data extraction were determined. Meta-analysis was performed using the random-effects model and meta-regression analysis. This systematic review included 33 studies, 11 prospective cohort studies, 9 retrospective cohort studies, and 13 randomised clinical trials. After applying the quality assessment criteria, 26 articles were included in the meta-analysis. The weighted pooled success rate was 83%, with a 95% confidence interval of 79-87% in studies that ranged from 6 months to 10 years. The meta-regression analysis showed that rubber dam isolation throughout all procedures was significantly more effective than other techniques (risk ratio=1.44; 95% confidence interval 1.06-2.16, p<0.05). This study provides evidence of successful treatment outcomes in direct pulp capping of permanent teeth, with "adequate tooth isolation" identified as a significant prognostic factor. (EEJ-2023-07-097)

Discipline-specific terminology is a central element of the vocabulary used by dentists and scientists in the context of their professional activities and plays a critical role in the understanding of dentistry. A number of controversial terms and non-standardized definitions exist in the field of endodontology. For example, in root and canal anatomy, variations are evident in the definitions of root morphology (including apical bifurcation, fusion and dilaceration), pulp chamber anatomy (including the outline of the floor, pulp horns and location of the root canal orifice), apical root canal bifurcations, canal isthmuses, accessory canals and apical foramen. This narrative review provides a critical analysis of a range of controversial terms currently used to describe root and canal anatomy. It also addresses the consequences of using such controversial terms on the accuracy and reliability of research findings and clinical practice. (EEJ-2024-07-119)

Objective: Endoplasmic reticulum (ER) stress plays important roles not only in stress avoidance, but also in cell differentiation and maturation, cell proliferation, and promotion of bone formation. This study aimed to investigate the involvement of ER stress in the onset of pulpitis.
Methods: Immunohistochemical analysis was conducted on human teeth extracted for orthodontic reasons. The effects of tunicamycin (TM), an inducer of ER stress, lipopolysaccharide (LPS), and 4μ8c, an inhibitor of inositol-requiring enzyme 1 (IRE1) on cultured human dental pulp cells (hDPCs) were also examined.
Results: The expressions of two ER stress markers, X-box binding protein (XBP)-1 and binding immunoglobulin protein (BiP)/78 kDa glucose-regulated protein (GRP78), were found in the human pulp tissues of a decayed tooth that had not developed irreversible acute pulpitis, but not in an impacted tooth without inflammation in pulp tissue. Both TM and LPS increased the mRNA levels of XBP-1, interleukin (IL)-6, and IL-8, whereas TM, but not LPS, enhanced the mRNA expression of BiP/GRP78 in hDPCs. 4μ8c significantly suppressed the in-creased level of XBP-1 by LPS.
Conclusion: This study demonstrated that XBP-1, in addition to inflammatory cytokines, may participate in the onset of pulpitis through IRE1. These findings provide a more comprehensive understanding of pulpitis pathogenesis through the cooperation of ER stress and inflammatory cytokines. (EEJ-2024-05-082)

Objective: To evaluate the effect of a newly developed MTA-based material and two antibacterial-enhanced MTAs as pulp capping materials in immature permanent dental elements underwent full pulpotomy.
Methods: The present animal study included 20 Wistar albino rats that, after full pulpotomy, were randomly divided into 4 groups receiving different MTA formulations as pulp capping materials: conventional MTA, Tricalcium aluminate (TCA)- free MTA, and MTA enhanced with metronidazole or doxycycline. Histopathological assessments were carried out at 7- and 28-days post-treatment to evaluate dentinal bridge formation, inflammatory reactions, pulp tissue necrosis and internal resorption.
Results: Seven days post-treatment, all groups exhibited inflammation and pulp necrosis, that were minimal in Groups III and IV than Group I. Group II showed a statistically significant difference only in terms of pulp necrosis (p<0.001). At 28-days all Groups showed slight inflammation and pulp necrosis, mainly in Groups I. Dentinal bridge formation was appreciated in all samples belonging to Groups II, III and IV and in 7/10 specimens of Group I, resulting in a statistically significant difference (p≤0.001).
Conclusion: TCA-free MTA and antibiotic-enhanced MTAs showed superior performances in dentinal bridge formation and exhibited minimal pulpal necrosis than conventional MTA. The inclusion of antibiotics might contribute to create a more sterile environment that would improve the outcomes, favoring deposition of a mineralized matrix. However, further studies are needed to support these preliminary results. (EEJ-2024-10-157)

Objective: This study aimed to evaluate pulp regeneration by comparing the application of native chitosan-based scaffolds with enzymatically modified chitosan-based scaffolds in mature teeth with apical lesions, using clinical and radiographic assessments.
Methods: The eligibility criteria for this study were participants aged between 15–45 years, free from systemic diseases and with necrotic mature single-rooted teeth with periapical lesions. The teeth were equally and randomly allocated into three groups (1: 1: 1 allocation): Group A received treatment with a Blood Clot (BC) scaffold; Group B with a combination of Native Chitosan and Blood Clot (NCS+BC) scaffold; and Group C with Enzymatically-Modified Chitosan and Blood Clot (EMCS+BC) scaffold. Clinical procedures were performed over two appointments. During the first appointment, canals underwent standardized mechanical and chemical preparation, followed by a modified triple antibiotic paste application, then sealed with glass ionomer cement. After three weeks, the antibiotic paste was removed. Subsequently, the regenerative procedure was conducted based on the group assignment. Participants were monitored at one, three, six-, and twelve months post-treatment to evaluate the treated teeth clinically and radiographically, focusing on the status of periapical lesions and tooth sensibility through cold testing. Statistical analysis included the Kruskal-Wallis and Mann-Whitney U tests to determine significant differences in healing degrees among the three groups over time. Additionally, the Chi-square test was used to assess significant differences in tooth sensibility frequencies during the cold test across the groups.
Results: Thirty teeth from twenty-four participants were included. There were no significant differences in the frequencies of healing degrees among the three studied groups (BC, NCS+BC, EMCS+BC) after one, three, and twelve months. The degree of healing after six months in the EMCS+BC group was higher than in other groups, and there were no statistically significant differences in the frequencies of healing degrees after six months between the NCS+BC group and BC group. The frequencies of tooth sensibility in the cold test among the three studied groups (BC, NCS+BC, EMCS+BC) were significantly different after six and twelve months. The tooth sensibility in the BC group was smaller than that of both the NCS+BC group and EMCS+BC group, and there were no statistically significant differences in the frequencies of tooth sensibility between the NCS+BC group and EMCS+BC group.
Conclusion: The application of the EMCS+BC scaffold demonstrates superior outcomes in pulp regeneration after six months, with a higher degree of healing observed compared to the NCS+BC and BC groups. There were no statistically significant differences at one month, three months, and twelve months. Additionally, tooth sensitivity was more pronounced in the EMCS+BC and NCS+BC groups. (EEJ-2024- 08-132)

Objective: The purpose of this randomized, controlled study was to evaluate the effectiveness of Biodentine compared with MTA used as a pulp space barrier in healing periapical lesions and regaining pulp sensitivity after regenerative treatment in mature single-canal permanent teeth with pulp necrosis and apical periodontitis.
Methods: The study involved 36 patients with mature teeth with necrotic pulp and apical periodontitis. The patient underwent a regenerative treatment that utilized the blood clot technique. Teeth were randomly allocated to either the intervention, Biodentine, group (n=18) or the control, MTA, group (n=18). The healing of periapical lesions and tooth sensibility were evaluated throughout follow-up visits for up to 18 months.
Results: The study analyzed 31 patients; two patients within the biodentine group and three in the MTA group were lost to follow-up. After 18 months, both groups showed effective healing of periradicular lesions; 21 out of 31 patients (67.7%) were healed, ten patients (32.3%) were healing, and no failure cases occurred. There were no significant differences between the groups (p=1.00). More than 70% patients (22 out of 31) regained teeth sensibility, and the groups had no statistically significant difference (p=0.703).
Conclusion: Regenerative treatment using blood clots with either MTA or Biodentine effectively resolved periapical lesions and regained the sensibility of mature teeth. (EEJ-2024-03-053)

Objective: Our purpose was to investigate the physicochemical properties of Bio-C Temp (Angelus, Londrina, PR, Brazil), a bioceramic intracanal medication, and whether its residues remain adhered to dentine walls after conventional manual irrigation (CMI) or passive ultrasonic irrigation (PUI) in comparison to the Calen (SS. White, Rio de Janeiro, RJ, Brazil).
Methods: The pH after 12 hours, 1 day, 3 days, 7 days, 14 days, 21 days and 28 days and the flow, radiopacity, and solubility of the medications after immersion for 7 and 30 days in distilled water (dH2O) or phosphate-buffered saline (PBS) solution were evaluated. Filling capacity and volumetric changes after 14 days were assessed by micro-computed tomography (micro-CT). The residues of medications after CMI or PUI were analysed with scanning electron microscopy. Statistical analysis was performed using ANOVA and Tukey’s post-hoc test, Student’s t-test, or the Kruskal-Wallis and Dunn post-hoc test (α=0.05).
Results: Bio-C Temp presented lower pH, flow, volumetric change, and weight loss after immersion in PBS on the 7th and 14th days (p<0.05) and greater radiopacity and filling capacity (p<0.05) than Calen. Both medications showed lower solubility in PBS than in dH2O (p<0.05). There was no difference in the residue content of the two medications between the two irrigation methods in three-thirds of the roots (p>0.05).
Conclusion: Although Bio-C Temp had less volumetric loss and satisfactory filling capacity, this medication provided lower alkalinity than Calen. Furthermore, neither CMI nor PUI completely removed the medicament residues within the human root canal. (EEJ-2024-02-041)

Objective: To evaluate the outcome of teeth filled with a single cone technique and a premixed bioceramic sealer at 3 years of follow-up.
Methods: Healthy patients were consecutively treated by a cohort of postgraduate operators. Root canal filling procedures were performed with NiTi rotary instrumentation, while non-surgical retreatments were performed using NiTi reciprocating instruments. Root canal filling procedures were performed using Ceraseal and the single cone technique. Post-endodontic restorations were performed after 15 days. Provisional and definitive crowns were positioned in case of non-sufficient coronal structure. Periapical radiographs were made before treatment, after filling, and at each follow-up visit (6, 12, 24 and 36 months). The periapical Index (PAI) was used to assess the presence of periapical lesions and their modifications over time. Success (absence of periapical radiolucency, PAI <3) and survival rates were evaluated. The presence of apical extrusion was also radiographically assessed. Linear regression analysis was used to investigate changes in mean PAI scores, and logistic regression analysis was used to investigate changes in the percentage of healed cases. All analyses were replicated using two distinct approaches: per protocol (PP) (treatments who completed the follow-up) and intention to treat (ITT) (all root canal treatments). A significance level of 5% was used for all statistical tests (α=0.05).
Results: Fifty-eight endodontic treatments in 52 patients were performed (ITT). Thirty-eight endodontic treatments in 33 patients completed the 3 years of follow-up with a survival rate of 92.7%. The success rate was 85.4% (PP).
Conclusion: The use of Ceraseal associated with the single cone technique was safe in maintaining endodontically affected teeth. (EEJ-2024-01-02)

Objective: To investigate significant differences in selected radiomic parameters when classifying periapical lesions based on volumetric size, cortical expansion, erosion, and shape using Cone Beam Computed Tomography (CBCT).
Methods: A retrospective analytical and comparative study was conducted on 100 small field of view (FOV) 50×50 mm CBCT scans collected between the years 2018 and 2023. The study involved qualitative classification of periapical lesions, followed by segmentation and extraction of radiomic parameters. The extracted parameters included first-order features such as energy, entropy, total energy, and uniformity; texture features like grey-level co-occurrence matrix contrast (GLCMC) and neighbouring grey tone difference matrix contrast (NGTDMC); and shape features including elongation, flatness, sphericity, and mesh volume, utilising 3D Slicer and Pyradiomics. The normal distribution of the variables was determined using the Shapiro-Wilk test. Various tests were used to assess significant differences, including Student’s t-test, Mann-Whitney U test, ANOVA, and Tukey’s post hoc analysis.
Results: Significant differences were observed in the following parameters among the classification levels when classifying periapical lesions according to their volumetric size. There were significant differences in energy with a p-value of 0.001 and total energy with a p-value of 0.02. NGTDMC also showed a significant difference with a p-value of 0.001. A larger volumetric size is associated with greater energy and lower contrast. Significant differences in periapical lesions with erosion were found in shape sphericity (mean 0.34, SD 0.10, p=0.01), energy (mean 3.73×10¹⁰, SD 4.52×10¹⁰, p=0.002), and NGTDMC (mean 0.05, SD 0.02, p=0.001) compared to lesions without erosion. GLCMC was lower in erosive lesions (mean 18.94, SD 6.81, p=0.03) than in non-erosive ones (mean 22.28, SD 8.48). Regular-shaped periapical lesions demonstrated significantly greater elongation (mean 0.794, SD 0.115, p=0.006) and flatness (mean 0.614, SD 0.107, p=0.005) than irregular-shaped lesions. These findings suggest that regular-shaped periapical lesions are more elongated and flatter than irregular ones. No significant differences were found in radiomic features depending on the presence or absence of expansion in the periapical lesion.
Conclusion: There are significant differences in texture and first-order radiomic features in periapical lesions classified based on size, erosion, and shape. This research's relevance lies in its potential to improve the quantitative characterisation of periapical lesions, leading to an objective interpretation. (EEJ-2023-11-159)

Objective: The final irrigation solution should have the capability of a chelation agent to remove the smear layer. The purpose of this study was to determine the effect of Ethylenediaminetetraacetic acid (EDTA), novel silver citrate, and chitosan nanoparticles as a final irrigation solution on the mechanical properties of root canal dentine, namely the flexural strength and elastic modulus.
Methods: Thirty-two intact, single, and straight roots, with no caries, no cracks, and no restoration of premolars, were assigned into four groups of 8 teeth each. Group 1: irrigated with EDTA; Group 2: irrigated with novel silver citrate; Group 3: irrigated with chitosan nanoparticles; Group 4: irrigated with saline as control. Using a Universal Testing Machine, each sample was tested for flexural strength and elastic modulus with a three-point bend test. The data were analysed using one-way ANOVA and followed by the Tukey’s test with a significance level of 0.05 (p=0.05).
Results: Chitosan nanoparticles generated the highest flexural strength and elastic modulus of root canal dentine (212.03±1.64 and 16.40±1.05, respectively) than EDTA (127.10±0.90 and 7.37±0.94) and novel silver citrate (177.87±2.03, and 12.27±1.01) (p<0.05). However, chitosan nanoparticles have similar flexural strength and elastic modulus of root canal dentine when compared to saline (213.76±1.48, 17.02±1.14, respectively) (p>0.05).
Conclusion: Among final irrigations used, chitosan nanoparticles produced the highest flexural strength and elastic modulus of root canal dentine compared to EDTA and novel silver citrate. (EEJ-2024-02-035)

Objective: This study aimed to evaluate the antibacterial efficacy of different concentrations of GH12 on a simulated multispecies biofilm comprising Enterococcus faecalis, Streptococcus mutans, Fusobacterium nucleatum and Porphyromonas gingivalis.
Methods: Single rooted teeth were decoronated, cut into 1.5 mm sections to obtain dentine discs which were randomly allocated into five groups: (n=12 each), Group 1: Phosphate Buffered Solution (PBS) - negative control, Group II: 5% Sodium hypochlorite (NaOCl) - positive control, Group III: Minimum Inhibitory Concentration (MIC) of GH12, Group IV: 2x MIC of GH12, Group V: 4x MIC of GH12. Colony forming units, Crystal violet assay and scanning electron microscopy examinations were performed. One-way ANOVA and Turkey’s test were applied for statistical analysis using the SPSS software version 22.0.
Results: Group II (NaOCl) showed maximum reduction in bacterial load followed by Group V (GH12 16mg/mL) with no statistically significant difference (p=1.000). On comparing the mean CFU reduction, the maximum reduction was identified for S. mutans and the least was for P. gingivalis. There was marked erosion observed in the NaOCl group whereas the GH12 group showed no erosive changes in the morphology and no bacterial colonies was identified.
Conclusion: The findings revealed that GH12 at higher concentrations inhibits and disrupts the growth of multispecies endodontic biofilm comparable to NaOCl but without erosive effects to the dentine, further highlighting its potential to be used as an antimicrobial solution. (EEJ-2023-10-147)

Objective: To investigate the effect of increasing the apical size of roots enlarged for root canal filling on the outcome of non-surgical endodontic treatment for teeth with apical periodontitis.
Methods: In this retrospective study, a total 210 cases of single-rooted canals treated were included at the dental units between October 2009 and January 2022. The International Organization for Standardization (ISO) standard number of gutta-percha points used for root canal filling and the presence or absence of apical bone resorption on dental radiographs were analysed to evaluate the treatment outcome and analyzed by chi-square test and multivariate logistic regression model.
Results: The number of teeth with a root apical size of ≤50 and ≥55 were 158 and 52, respectively. For the teeth with a root apical size of ≤50, 144 (68.6%) had good prognoses and 14 (6.7%) had poor prognoses. For the teeth with a root apical size of ≥55, 28 (13.3%) teeth had good prognoses and 24 (11.4%) had poor prognoses (p<0.0001).
Conclusion: Unfavourable clinical outcomes were observed in root canal-filled teeth with an enlarged apical root size of ≥ 55. Thus, these sizes potentially indicate poor outcomes of nonsurgical endodontic treatments. (EEJ-2023-09-126)

Objective: The present study aimed to evaluate the effect of heat-treated nickel titanium (NiTi) files TruNatomy and XP- Endo Shaper on the major apical foramen deformation and enlargement in curved root canals using area, circularity, and Feret’s diameter ratio.
Methods: Sixty mesio-buccal roots of maxillary and mandibular molars with Vertucci type II root canal were selected. The teeth were decoronated using a carborundum disc. The roots with a length of 13 mm were measured using a digital caliper. The preoperative scanning electron microscope images of apical roots were taken and then divided into 4 groups. Manual (K file, Mani Tochigi, Japan), ProTaper Universal (PTU, Dentsply Maillefer, Ballaigues, Switzerland), XP-Endo Shaper (XPS;FKG Dentaire SA, La Chaux-de-134 Fonds, Switzerland), and TruNatomy (TRN;Dentsply Sirona, Ballaigues, Switzerland) group. After instrumentation, the post-operative scanning electron microscope images were taken. Surface area, circularity, and Feret’s diameter ratio was calculated before and after instrumentation using Image J software. For intergroup comparison of data, student’s independent t-test was employed and for intra-group comparison of data, paired t-test was applied.
Results: The area after instrumentation increased in all groups but the K file and PTU show statistically significant differences compared to TRN and XPS (p<0.001). The circularity tends towards 0 in K file and PTU and canals became ellipticals after instrumentation. However, TRN and XPS showed no difference. There is no significant difference in the Feret’s diameter ratio before and after instrumentation.
Conclusion: The enlargement of the major apical foramen occurs regardless of the type of file system used. The hand K files and PTU result in significant foramen deformation when instrumented up to the major apical foramen. However, TRN and XPS promote minor alterations at the foramen which are not statistically significant. (EEJ-2024-01-20)

Objective: This double-blinded randomized clinical trial aimed to compare postoperative pain using 2Shape® (TS) in rotary (TSRot) and adaptive (TSAK) kinematics in the maxillary and mandibular molars in patients with symptomatic irreversible pulpitis and symptomatic apical periodontitis following single-visit endodontic treatment.
Methods: Seventy patients were randomly assigned to two groups (TSRot /TSAK), (n=35 each). The preoperative and postoperative pain intensities at various time intervals up to 72h using a Visual-Analogue Scale was noted. Mann-Whitney U test (p<0.05*) was used to compare pain intensity, and the chi-square test was used to compare the incidence of pain. Dunns test (p<0.05*) was used for intragroup comparisons. Binary logistic regression was performed at consecutive time intervals.
Results: A total of 67 patients were included in the final analysis, and three were excluded due to medication intake. Both groups showed a gradual reduction in the mean incidence and intensity of postoperative pain from 6 to 72 hours. However, TSAK had a significantly lower intensity and incidence of pain than TSRot at 24h (p=0.02*). There was no statistically significant difference observed in the duration of instrumentation when the TS file was used in either adaptive or rotary kinematics (p=0.41).
Conclusion: Adaptive kinematics (TSAK) resulted in less pain incidence compared with rotary kinematics (TS-Rot). A statistically significant difference in incidence was observed at 24 h but may not be clinically significant. The duration of instrumentation was similar between the TSRot and TSAK groups. Thus, the 2Shape® (TS) file, which is a rotary file, can be used in adaptive kinematics to reduce the postoperative pain. (EEJ-2024-02-036)