Objective: The purpose of this prospective, randomized clinical trial was to evaluate the effect of cooling a 2% lidocaine solution with 1: 200,000 epinephrine, administered as a supplementary intraligamentary injection to overcome a failed primary inferior alveolar nerve block (IANB).
Methods: The study was preceded by a pilot study to evaluate the anesthetic efficacy of plain lidocaine solutions given as intraligamentary injections. In the subsequent randomized clinical trial, one hundred and thirty-eight patients received IANB with 2% lidocaine with 1: 80,000 epinephrine for endodontic man- agement of a mandibular molar with symptomatic irreversible pulpitis. Eighty-eight patients reported pain greater than 54 mm on a visual analog scale (Heft-Parker VAS) were categorized as unsuccessful anesthesia. These patients received either of the following intraligamentary injections: 2% lidocaine with 1: 200,000 epinephrine at room temperature; or 2% lidocaine with 1: 200,000 epinephrine at 4°C. Anes- thetic success was again evaluated after re-initiation of the endodontic treatment. The heart rates of the patients were measured using a finger pulse oximeter. The categorical success rates were statistically analyzed with the Pearson chi-square test at 5% significance levels. The heart rate measurements were analyzed using a t-test.
Results: The intraligamentary injections with anesthetic solutions at room temperature presented a suc- cess rate of 59.1%, while the injections with a solution at 4°C gave a success rate of 52.27%. There were no significant differences between the success rates of the groups (χ2=0.41, p=0.52). Regarding the heart rates, there were no differences between the two solutions at baseline (T=1.2, p=0.2) or after injections (T=0.64, p=0.52).
Conclusion: Reducing the temperature of 2% lidocaine with 1: 200,000 epinephrine to 4°C does not affect the anesthetic efficacy of supplemental intraligamentary injections, given after a failed primary IANB. (EEJ-2023-03-044)

Objective: The objective of this study was to evaluate the effectiveness of preoperative analgesics on inferior alveolar nerve blocks (IANB) during root canal treatment in patients with symptomatic irreversible pulpitis of the mandibular molars.
Methods: This study was a randomized, double-blinded, superiority trial with a parallel study design. A total of 120 subjects with symptomatic irreversible pulpitis were randomly assigned to one of four groups: group A (con- trol, Vitamin E, Evion 400 mg), group B (Diclofenac sodium, Voltral SR100 100 mg), group C (Piroxicam, Feldene 20 mg), and group D (Tramadol, Tramal 50 mg). The patients recorded preoperative pain levels, and after admin- istration of local anaesthesia intraoperative pain levels using the Heft-Parker visual analogue scale before and after the oral administration of the analgesics. Statistical analysis was performed using the Kruskal-Wallis test.
Results: All the analgesic groups showed a significant effect on the efficacy of the inferior alveolar nerve block in contrast to the control group (p<0.05). However, no significant difference was found between the drug groups on the effectiveness of the inferior alveolar nerve block (p>0.05). No side effects were reported in the present study.
Conclusion: Preoperative analgesics significantly increase the effectiveness of inferior alveolar nerve block in patients with symptomatic irreversible pulpitis. Therefore, preoperative analgesics should be considered to increase the effectiveness of inferior alveolar nerve block in patients with symptomatic irreversible pulpitis on the mandibular molars. (EEJ-2023-02-033)

Objective: The primary objective of this randomised clinical trial was to evaluate the efficacy of Calcium Enriched Mixture (CEM) cement compared to Mineral Trioxide Aggregate (MTA) and Calcium Hydroxide (CH) in maintaining pulp vitality when used for direct pulp capping (DPC) of deep carious lesions with reversible pulpitis and secondary objective was to assess the overall success of DPC in carious exposures.
Methods: One hundred and fifty patients diagnosed with reversible pulpitis with deep carious lesions were included in this study. Patients were randomly allocated into three groups (n=50), Group C: CEM group, Group M: MTA group, and Group D: CH (Dycal) group. After caries removal by mechanical excavation except for one carious spot, the removal of which resulted in the exposure of the pulp, the final carious spot was removed with a sterile no.2 round carbide bur. After haemostasis, the pulpal wound was dressed by a capping agent, followed immediately by permanent restoration. Patients were assessed for successful outcomes based on positive vitality tests, absence of clinical signs and symptoms, and PAI scores after 1, 3, 6, 12, and 18-month follow-up periods. The ANOVA test was employed to analyse quantitative variables, and the Pearson Chi-square test was used for qualitative variables. A Bonferroni Test was employed as the post hoc test for intergroup comparison. The significance level was set at p≤0.05 within all tests.
Results: The percentage of success in Group C was 86.7%, Group M was 77.3%, and Group D was 57.9%. This study’s overall success rate after direct pulp capping of deep carious lesions was 74.8%. A statistically significant difference in PAI score was found between Groups C and D. Pain on percussion and response to vitality tests also showed significant differences among the three groups at the one-month follow-up.
Conclusion: CEM cement had comparable efficacy to MTA and was superior to CH in maintaining pulpal vitality following DPC in teeth with reversible pulpitis. An overall success rate of 74.8% indicated that DPC in deep carious lesions with reversible pulpitis could yield favourable clinical outcomes. (EEJ-2022-11-134)

Objective: To compare rotations to failure and tip separation length of a nickel-titanium (Ni-Ti) rotary in- strument within a simulated mesio-buccal canal of a mandibular molar with a conventional or contracted endodontic cavity.
Methods: Two identical lithium disilicate #30 crowns were milled. A conventional or contracted endodontic cavity was prepared. A custom glass tube was fabricated with taper and length replicating a mesio-buccal canal, including buccal and lingual curvature, and placed at the mesio-buccal orifice of each crown, held in a silicone mold. Instrumentation was simulated using 30/.04 Ni-Ti rotary files following manufacturer recommended 1.8 Nm torque and 500 RPM (n=20 per access type). Instrumentation was video recorded to determine time (sec- onds) and rotations to failure. The length of broken tips was measured. The experimental data were compared using a t-test (significance level 0.05). Stresses in the instruments were examined using finite element analysis.
Results: Number of rotations to failure (mean±standard deviation) was 599±126 for conventional and 465±65 and for contracted access; tip separation lengths (mean±standard deviation) were 3.99±0.29 for conventional and 4.90±1.02 mm for contracted access. Number of rotations to failure and tip separation lengths were signifi- cantly different between the two access openings (p<0.001). Finite element analysis confirmed higher file curva- ture and accompanying higher stress levels with contracted access and the maximum stress further from the tip.
Conclusion: Within the limitations of this study, the contracted access caused earlier failure of the Ni-Ti in- strument with longer tip separation lengths than the conventional access due to higher stresses towards the middle section of the instrument. (EEJ-2022-11-143)

Objective: The aim of this study was to compare the effect of ultrasonic activation (UA) on tubular penetration between Bio-C Temp and Ultracal XS intracanal medicaments.
Methods: Forty single-rooted human premolars were endodontically prepared and divided into 4 experimental groups (n=10): Bio-C Temp, Bio-C Temp+UA, UltraCal XS and UltraCal XS+UA. All medicaments were previously mixed with a specific calcium marker (Fluo-3) and passively injected into the canals. The samples were incubated for 7 days. For each tooth, 1 mm thick sections were obtained from the middle and apical thirds of the canals. The samples were examined by confocal laser scanning microscopy (CLSM) and the depth and area of penetration were determined for each group. The Student t test was used to compare results between groups (p<0.05).
Results: UA increased the depth and penetration area of Bio-C Temp and Ultracal XS, showing significant differences
in the penetration area of the apical third for Bio-C Temp (p<0.0339). Bio-C Temp presented greater tubular penetration than Ultracal XS, showing significant differences in the depth of penetration in the apical third (p<0.0005), and in the penetration area in the middle (p<0.0016) and apical third (p<0.0339) after UA.
Conclusion: UA increases tubular penetration (both depth and area) of Bio-C Temp at the apical third but has no significant effect on Ultracal XS. Bio-C Temp has a greater depth and tubular penetration area than Ultracal XS after UA. (EEJ-2023-02-024)

Objective: Mechanical instrumentation of the root canal system generates a smear layer on the canal walls which are removed most commonly with the help of chelators such as ethylenediaminetetraacetic acid (EDTA) but can potentially cause severe dentinal erosion. Considerable research has been conducted to find an al- ternative to EDTA which removes the smear layer without causing dentinal erosion. The current study aimed at evaluating the ability of sodium gluconate compared with that of 17% EDTA in smear layer removal along with its effect on dentine decalcification when used as a final irrigant.
Methods: Twenty single-rooted mandibular premolars were collected and prepared based on the pre-set criteria. Following preparation, the specimens were exposed to the test solutions as a final irrigant. Then the specimens were subjected to (Scanning electron microscope) SEM analysis at 1000x for evaluating the smear layer and 5000x for evaluating the dentinal erosion, and a Vickers microhardness tester was used for evaluat- ing the reduction in dentine microhardness post-treatment. The values obtained were analysed using SPSS software for a statistically significant difference with Mann-Whitney U test for evaluating of smear layer remov- al and dentinal erosion and using one-way (Analysis of variance) ANOVA test for microhardness evaluation.
Results: The smear layer removal capability of sodium gluconate was as effective as EDTA on the contrary so- dium gluconate did not cause any dentinal erosion compared to EDTA with a statistically significant difference (p=0.002 in middle third and p=0.001 in apical third of the canal). Microhardness reduction caused by sodium gluconate was less compared to EDTA, however, no statistically significant difference (p=0.113) was noted.
Conclusion: Sodium gluconate, therefore, can produce a balance between smear layer removal and dentinal decalcification and can be considered a potential alternative to EDTA. (EEJ-2023-01-017)

Objective: Hyaluronic acid (HA) is glycosaminoglycan and one of important factors in extracellular matrix. In an inflamed pulp, when niche biology is conducive, the recruitment of human dental pulp stem cells (hDPSCs) will take place and differentiate into odontoblast like cell, creating reparative dentine and expressing dentine sialophosphoprotein (DSPP). Therefore, the purpose of this study was to analyze the potential of hydrogel HA in various concentration towards hDPSCs differentiation via DSPP expression at day 7 and 14.
Methods: After hDPSCs incubation reaching 80% confluence, cells were then starved for 24 hours. Then, culture media were supplemented with osteogenic media. hDPSCs planted into 96 well plate and HA 10 μg/mL, 20 μg/mL, and 30 μg/mL were added. DSPP expression was analysed using elisa reader at day 7 and 14, qualitative result was analysed using alizarin red at day 21. Data was analysed using one-way ANOVA.
Results: At day 7, there was a statistically significant different potential of HA conditioned media in various concentration (p<0.05) towards hDPSCs differentiation via expression of DSPP with HA 30 μg/mL being the most potential concentration to increase DSPP expression.
Conclusion: HA have the potential to increase odontoblast differentiation process via expression of DSPP, with HA 30 μg/mL being the optimum concentration for hDPSCs. (EEJ-2022-12-169)

Objective: To investigate the concentration of Matrix metalloproteinases-9 (MMP-9) and Tumor necroses fac- tor-alpha (TNF- α) in pulpal blood at various stages of pulpal inflammation in diabetics and to establish the relationship between these two biomarkers.
Methods: 77 patients, each having a tooth with pulpal exposure due to caries presenting with distinct stages of pulpitis were grouped into 2 main study groups as based on the HbA1c Levels-Group 1: Non-Diabetics (Control Group) (HbA1c < 5.6%) and Group 2: Type 2 Diabetics (Experimental Group) (HbA1c>6.5%; Random Plasma Glucose > 200) and diabetes mellitus with less than 10-year history. Depending on the radiological and clinical diagnosis, these two groups were again sub-divided into 2 subgroups: Sub-group A: Tooth with Symptomatic Irreversible Pulpitis. Sub Group B: Tooth with Reversible Pulpitis. Thus, for comparison purposes, a total of 4 sub-divisions were formed: Sub-group 1A- Non-Diabetic, Symtomatic Irreversible Pulpitis, Sub- group 1B: Non-Diabetic, Reversible Pulpitis, Sub-group 2A: Diabetic, Symptomatic Irreversible Pulpitis, Sub- group 2B: Diabetic, Reversible Pulpitis. Blood sample was collected from pulp chamber after partial pulpo- tomy was done. The total levels of MMP-9 and TNF-α were assessed by enzyme linked immunosorbent assays (ELISA). Inter-group comparison in levels of MMP-9 and TNF- α were conducted using the Kruskal Wallis test and pairwise comparison was done Mann-Whitney U test.
Results: The inter-group comparison in levels of MMP-9 and TNF- α were conducted using the Kruskal Wallis test and pairwise comparison was done using Mann-Whitney U test. Pearson correlations were conducted in order to investigate correlations between the paired TNF-α and MMP-9 values and also their correlation with the blood sugar levels within the pulp diagnosis groups. MMP-9 and TNF-α levels were significantly higher (p<0.005) in irreversible pulpits than reversible pulpits and also in Type-2 diabetics than non-diabetics. High- est level of MMP-9 and TNF-α was found in Group 2A (Diabetic, symptomaticirreversible pulpitis) and lowest in Group 1B (Non-Diabetic, reversible pulpitis). There exists a very high significant positive correlation between MMP-9 & TNF-α (p<0.005).
Conclusion: These findings show that the inflammatory mediators MMP-9 and TNF-α are significantly in- creased in pulpal blood samples of diabetic patients. Also, in diabetic patients diagnosed with reversible pul- pitis, higher levels of inflammatory pulpal biomarkers were reported that could compromise the success of Vital Pulp Therapy (VPT) and may necessitate endodontic intervention. MMP-9 and TNF- α were reported to have a positive correlation. (EEJ-2023-01-04)