Synthesis of a Calcium Silicate Cement Containing a Calcinated Strontium Silicate Phase.

Objectives: The positive effects of strontium on dental and skeletal remineralization have been confirmed in the literature. This study aimed to assess the properties of a calcium silicate cement (CSC) containing a sintered strontium silicate phase. Materials and Methods: The calcium silicate and strontium silicate phases were synthesized by the sol-gel technique. Strontium silicate powder in 0 (CSC), 10 (CSC/10Sr), 20 (CSC/20Sr), and 30 (CSC/30Sr) weight percentages was mixed with calcium silicate powder. Calcium chloride was used in the liquid phase. X-ray diffraction (XRD) of specimens was conducted before and after hydration. The setting time and compressive strength were assessed at 1 and 7 days after setting. The set discs of the aforementioned groups were immersed in the simulated body fluid (SBF) for 1 and 7 days. The ion release profile was evaluated by inductively coupled plasma-optical emission spectrometry (ICP-OES). Biomineralization on the specimen surface was evaluated by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Data were analyzed by the Kolmogorov-Smirnov test, one-way and mixed ANOVA, Levene's test, and LSD post hoc test (P < 0.05). Results: Except for an increasement in the peak intensity of hydrated specimens, XRD revealed no other difference in the crystalline phases of hydrated and nonhydrated specimens. The compressive strength was not significantly different at 1 and 7 days in any group (P > 0.05). The setting time significantly decreased by an increase in percentage of strontium (P < 0.05). Release of Ca and Si ions significantly decreased by an increase in percentage of strontium (P < 0.05). SEM/EDS showed the formation of calcium phosphate deposits at 1 and 7 days. Conclusion: Incorporation of 10-30 wt% sintered strontium silicate phase as premixed in CSC can significantly decrease the setting time without compromising the compressive strength or biomineralization process of the cement.

The association of endodontic prognostic factors with the presence of periapical lesion, its volume, and bone characteristics in endodontically treated molars: a cross-sectional study.

BACKGROUND: This study intended to evaluate the association between several endodontic prognostic factors with the presence of periapical lesions (PLs), their volume, and bone characteristics including cortical bone destruction (CBD) and buccal plate bone height (BPBH) in root-filled molar teeth using cone-beam computed tomography. METHODS: A collection of 143 scans of endodontically treated maxillary/mandibular first or second molars recorded over 8 years, were obtained from a specialized radiology center. Data on prognostic factors including tooth number, gender, jaw type, the status and number of missed canals, obturation length, restoration type, presence of a separated instrument, presence of a post or screw in the canals, and presence of perforation were collected. The assessed outcomes included PL presence, PL volume, CBD, and BPBH. The association between prognostic factors and outcomes was evaluated using multiple logistic regression models with adjusted covariates and multifactorial ANOVA at a significance level of 0.05. RESULTS: A total of 282 molars from 82 women and 50 men with a mean age of 40.6 ± 12.27 were included. Among those, 139 teeth presented PL with a mean volume of 18.68 mm3. CBD was prevalent in 137 teeth and the mean BPBH appeared to be 9.45 mm. The presence of a missed canal (OR = 10.022, P < .05), underfilled canal (OR = 3.725, P < .05), overfilled canal (OR = 15.859, P = .018), and perforation (OR = 15.261, P = .013) was significantly associated with PLs. None of the prognostic factors could considerably contribute to the CBD (P > .05). The presence of a missed canal was positively associated with the PL volume (P < .05). Similarly, missed canals (P < .05), perforation (P < .05), and separated instruments (P = .004) were associated with a significantly reduced BPBH. CONCLUSIONS: Overfillings, perforations, missed canals, and underfillings were identified as remarkable predictors of PL, arranged in descending order of their respective impact. The only factor capable of significantly increasing the PL volume was the missed canal. In brief, obturation length errors, perforations, missed canals, and separated instruments were robustly correlated with endodontic failure, which highlights the importance of mitigating the potential for errors by following the fundamentals of endodontics.

Primary and supplementary anesthetic efficacy of a modified two-step buccal infiltration of 4% articaine in mandibular molars with symptomatic irreversible pulpitis: a randomized clinical trial.

OBJECTIVES: To evaluate a modified two-step buccal infiltration (MBI) of 1.7 mL 4% articaine as primary or supplemental anesthesia in mandibular first and second molars diagnosed with symptomatic irreversible pulpitis (SIP). MATERIALS AND METHODS: One hundred and eight patients with SIP were randomly assigned to one of three groups (n = 36). They were given an inferior alveolar nerve block (IANB) of 2% lidocaine with 1:80.000 epinephrine or a primary MBI of 4% articaine with 1:100.000 epinephrine in the IANB and MBI groups, respectively. Patients in the IANB + MBI group received an IANB followed by an MBI. Pain levels during the injection, access cavity preparation, and initial filing were recorded on the Heft-Parker visual analog scale (HP-VAS). No or mild pain (HP-VAS ≤ 54) upon access cavity preparation and initial filing was considered a success. Chi-square and Kruskal-Wallis tests were used to analyze the data. RESULTS: MBI (77.8%) and IANB + MBI (94.4%) had both significantly higher success rates than IANB (50.0%) (P < .001). However, when the Bonferroni adjustment was applied, there was no statistically significant difference between the MBI and IANB + MBI techniques (P = .041 > .017). MBI was associated with significantly less injection pain than IANB (P < .001). CONCLUSIONS: Both primary and supplemental MBI with 4% articaine were superior to IANB with 2% lidocaine in mandibular first and second molars diagnosed with SIP. Further research may be needed to confirm the findings of this study. CLINICAL RELEVANCE: The findings of this study suggest that supplemental or primary MBI can be a clinically viable alternative to IANB, which has a relatively low success rate when managing mandibular molars diagnosed with SIP.

Guided Endodontic Treatment for Calcified Central Incisor with Discoloration, a Conservative Approach Preserving Incisal Edge: A Case Report.

Pulp canal obliteration (PCO) in calcified teeth presents a challenge for endodontic treatment, especially when accompanied by discoloration. Guided endodontic access (GEA) has emerged as an advanced method for root canal therapy (RCT) in such cases. This case report describes the successful treatment of a calcified maxillary central incisor with discoloration using GEA. A 32-year-old female with a history of dental trauma presented with discoloration in the left maxillary central incisor that did not respond to external bleaching. Clinical examination revealed a pulpless infected canal with asymptomatic apical periodontitis. Cone-beam computed tomography (CBCT) and intraoral scanning were utilized to create a three dimensional (3D) template, enabling minimally invasive access preparation through the palatal aspect. The RCT was performed in a single visit, followed by tooth whitening using hydrogen peroxide. At 18 months follow-up, the tooth was asymptomatic, and the apical lesion was healed. GEA offers a predictable and conservative approach, preserving tooth structure and providing enhanced long-term prognosis for teeth with calcified canals and discoloration.

Comparative Evaluation of Canal Transportation and Centering Ratio in Curved Canals: A Study of Cone-beam Computed Tomography and Micro-computed Tomography.

Introduction: This study aimed to compare the accuracy and agreement between cone-beam computed tomography (CBCT) and micro-computed tomography (micro-CT) in the assessment of canal transportation and centering ratio following root canal instrumentation with rotary files. Material and Methods: Twenty mesiobuccal canals of mandibular molars were prepared using the 2Shape sequential rotary system. CBCT and micro-CT scans were performed before and after instrumentation, and the magnitude of transportation and centering ratio were measured. The acceptable transportation was set at ≤0.15 mm. The accuracy and agreement between CBCT and micro-CT were calculated, and the intra-class correlation coefficient (ICC) and kappa coefficient were determined to assess the agreement between the two modalities. Statistical analyses were performed using repeated measures ANOVA. Results: Transportation was detected by both modalities at all distances from the apex after instrumentation. The agreement between CBCT and micro-CT in assessing canal transportation was observed in 80%, 85%, 75%, and 75% of specimens at 1-, 3-, 5-, and 7-mm from the apex, respectively. The ICC for transportation and centering ratio was much lower than 0.75, indicating poor agreement between the modalities. The kappa coefficient did not show acceptable agreement between the methods. Conclusions: CBCT and micro-CT demonstrated poor agreement in assessing canal transportation and centering ratio. Micro-CT remains the preferred modality for in vitro investigations, while CBCT should be limited to clinical settings.

Treatment of Peri-Invagination Lesion and Vitality Preservation in Type III Dens Invaginatus in Bilateral Immature Maxillary Lateral Incisors: A Case Report.

The superior lateral incisors are primarily affected by the developmental deformity known as dens invaginatus (DI). Oehler's type III DI has the highest complexity rendering a root canal treatment (RCT) an arduous challenge for this type, so early diagnosis and treatment before pulp involvement are important. This report presents two maxillary lateral incisors with type IIIb DI, the left one being associated with a periapical lesion and the right one with normal pulp. A nine-year-old boy was referred to our clinic complaining of mobility of the maxillary left lateral incisor (LLI) associated with gumboil throughout the previous two months. Periapical radiolucency was visible on radiographs, as well as an invagination that crosses the apical foramen from the pulp chamber in both maxillary lateral incisors. The pulp of the main canal of LLI was vital and pseudo canals were necrotized and associated with chronic apical abscess. Based on the condition of the main pulp of maxillary lateral incisors, two separate treatments were carried out. RCT was done only for the pseudo canals in the LLI, while the main root canal was preserved. The right maxillary lateral incisor (RLI) had vital pulp with normal periapical tissue So the invagination was sealed as the tooth was erupting. During the one-year follow-up period, the development of the root in LLI with a thick root wall and closed apex was observed in the periapical radiograph but pseudo canals became infected and the tooth became symptomatic, therefore retreatment for pseudo canals was carried out. The RLI root was developed and the tooth was clinically asymptomatic, so it didn't need further treatment. Maintaining pulp vitality is crucial for type III Dens invaginated young permanent teeth since it could support root formation and improve long-term prognosis, and in cases with pulp involvement, non-surgical RCT is clinically predictable.

Analgesic Efficacy of Ketoprofen Transdermal Patch versus Ibuprofen Oral Tablet on Postendodontic Pain in Patients with Irreversible Pulpitis: A Randomized Clinical Trial.

Materials and Methods: In this randomized clinical trial, 64 patients who had mandibular first and second molars with irreversible pulpitis were randomly divided into two groups (n = 32) by stratified permuted block randomization. The experimental group used 60 mg KTP every 6 hours, and the control group received 400 mg ibuprofen tablets every 6 hours for 1 day. The severity of pain experienced by patients was quantified before and at 2, 4, 8, 12, 24, and 48 hours after endodontic treatment, using the numerical rating scale (NRS). Data were analyzed by using the t-test, Mann-Whitney test, and generalized estimating equation (GEE) (alpha = 0.05). Results: The pain score was not significantly different between the two groups at the baseline or any other postoperative time point (P > 0.05). The reduction in the pain score was significant in both groups from 2 to 10 hours and 10 to 48 hours, postoperatively (P < 0.001). The interaction effect of time and group was not significant on the postoperative pain score in the abovementioned time intervals, and the pattern of pain reduction was the same over time in both groups (P > 0.05). Conclusion: Both KTP and ibuprofen effectively decreased postendodontic pain. Considering the comparable pattern of pain reduction, KTP can be used as an alternative to ibuprofen tablets for effective pain control after endodontic treatment of mandibular first and second molars with irreversible pulpitis.

Antibacterial Efficacy of Polymer-Coated Ceramic Microparticles Loaded with a Modified Combination of Antibiotics on the Enterococcus faecalis Biofilm.

Introduction: Nano-technology applied for the local delivery of different agents and/or drugs has made its path to endodontics. In the current study, the antibacterial efficacy of biopolymer-coated ceramic microparticles loaded with a modified combination of triple antibiotics, i.e. Penicillin G, Metronidazole and Ciprofloxacin (PMC), was evaluated against two strains of Enterococcus faecalis (E.faecalis); a standard clinical strain obtained from previously root-filled teeth with persistent periapical lesions, and compared to the most common antimicrobials used in endodontics. Methods and Materials: After synthesis of the polymer-coated microparticles loaded with antibiotics, the 21-day release of antibiotics were evaluated and a stock solution was produced using the maximum released amount of drugs and distilled water. The antibacterial activity of PMC, triple antibiotic paste (TAP), calcium hydroxide (CH), chlorhexidine (CHX) and sodium hypochlorite (NaOCl) against two bacterial strains was determined using "Minimum Inhibitory Concentration" and "Agar Diffusion Test". Additionally, "Microtiter Plate Assay" was performed to assess anti-biofilm properties. Results: Minimum inhibitory concentration values reported for TAP and PMC were 1/256. PMC showed the maximum diameter of growth inhibition in both strains (33 mm and 35 mm), while CH had the minimum diameters (13 mm and13 mm). Based on microtiter plate assay, TAP showed higher biofilm formation than PMC. Biofilm formation was higher in the standard strain for PMC; however, NaOCl, CHX and CH completely inhibited biofilm formation. Conclusions: Based on the findings of the present study, it could be concluded that PMC and TAP were the most effective medicaments against E.faecalis in its planktonic form; however, none could inhibit its biofilm formation. Further studies using larger sample size and "Confocal Scanning Laser Microscopy" are recommended.

The Evaluation of Debris and Smear Layer Generated by Three Rotary Instruments Neo NiTi, 2Shape and Revo_S: An Ex-vivo Scanning Electron Microscopic Study.

Introduction: This study compared the cleaning effectiveness of NeoNiTi, 2Shape and Revo_S rotary instruments. Materials and Methods: Fifty mandibular molar mesial roots were selected with an angle of curvature less than 20 degrees divided into three groups (n=15). Five samples were selected as negative control group. In all three systems, the final file was 25, 6%. The score of debris and smear layer in three thirds (coronal, middle and apical) of the root canal walls were evaluated using scanning electron microscopic (SEM) magnification. The data were analyzed using the Kruskal Wallis and Mann Whitney U tests for intergroup comparison (P≤0.05) and Freidman and Wilcoxon signed-rank test was employed for intragroup comparison (P≤0.05). Results: Residual debris of the 2Shape system in the apical region was significantly higher than the other two systems (P=0.039). Revo_S and 2Shape groups had significantly higher quantities of debris in the apical than the coronal region (P=0.029 and P=0.02, respectively). In the 2Shape group, the amount of mid-region debris was significantly higher (P=0.005) than the coronal. In inter-group comparison there was no significant difference in residual smear layer between the systems. In intra-group comparison in all three systems, the amount of smear layer in the coronal third was significantly higher than in the other two areas. (P=0.017, P<0.001 and P=0.032, respectively). Conclusion: 2Shape left the highest amount of debris in the apical region. The amount of debris in Revo_S and 2Shape groups in the apical region was significantly higher than in the coronal. The amount of smear layer in all three groups in the coronal area was higher than the middle and apical areas.

Analgesic Efficacy of Ibuprofen and Diclofenac Potassium on Postoperative Endodontic Pain in Maxillary and Mandibular First Molars with Irreversible Pulpitis: A Randomised Controlled Trial.

OBJECTIVE: The management of postoperative endodontic pain (PEP) is essential to contemporary endodontic practice. Diclofenac and ibuprofen (IBU) are two of the most widely-used non-steroidal anti-inflammatory analgesics. However, their comparative data are neither sufficient nor conclusive. This prospective randomised clinical trial aimed to compare the analgesic efficacy of diclofenac potassium (DFK) with IBU on PEP in maxillary and mandibular first molars diagnosed with irreversible pulpitis after single-visit non-surgical root canal treatment. METHODS: Sixty-four patients were randomised into two groups of DFK (n=32) and IBU (n=32), using the stratified permuted randomisation method, and 61 participants completed the trial. After root canal treatment, patients randomly received IBU 400 mg every 6 hours (n=31) or DFK 50 mg every 8 hours (n=30) for 24 hours. Patients recorded their pain level on 0-100 mm visual analogue scales (VAS) at 2, 4, 6, 12, and 24 hours after the treatment. Recorded VAS scores and the number of pain-free patients (VAS<5) were compared between the two groups. A generalised linear estimation equation model, Chi-Square test, and Mann-Whitney U test were used to analyse the data. RESULTS: The mean overall PEP score was statistically significantly lower in the DFK group than the IBU group with a p value of 0.030. Pain scores at 2 (p=0.034), 4 (p=0.021), and 24 hours (p=0.042) after the treatment were also significantly lower for DFK than IBU. The number of pain-free patients was also significantly higher in the DFK group at 2-hour (p=0.015) and 4-hour (p=0.048) time points and overall (p=0.013) compared to the IBU group. There was no adverse effect observed in either group. CONCLUSION: Based on the results, taking multi-dose DFK 50 mg by the clock had better analgesic outcomes than multi-dose IBU 400 mg for PEP management. (EEJ-2022-01-07).

Antibacterial efficacy of antibiotic pastes versus calcium hydroxide intracanal dressing: A systematic review and meta-analysis of ex vivo studies.

Background: Conflicting findings on the potency of antibiotic pastes versus calcium hydroxide (CH) have been evident in the literature. Aims: To compare the antibacterial efficacy of single antibiotic paste (SAP), double antibiotic paste (DAP), triple antibiotic paste (TAP), and modified TAP (mTAP) with CH on bacterial biofilms. Methods: PubMed, Scopus, and Embase were comprehensively searched until August 23, 2021. The study protocol was registered in the PROSPERO. Ex vivo studies performed on Enterococcus faecalis or polymicrobial biofilms incubated on human/bovine dentin were selected. The quality of the studies was assessed using a customized quality assessment tool. Standardized mean difference (SMD) with a 95% confidence interval (CI) was calculated for the meta-analysis. Meta-regression models were used to identify the sources of heterogeneity and to compare the efficacy of pastes. Results: The qualitative and quantitative synthesis included 40 and 23 papers, respectively, out of 1421 search results. TAP (SMD = -3.82; CI, -5.44 to -2.21; P < 0.001) and SAPs (SMD = -2.38; CI, -2.81 to - 1.94; P < 0.001) had significantly higher antibacterial efficacy compared to the CH on E. faecalis biofilm. However, no significant difference was found between the efficacy of DAP (SMD = -2.74; CI, -5.56-0.07; P = 0.06) or mTAP (SMD = -0.28; CI, -0.82-0.26; P = 0.31) and CH. Meta-regression model on E. faecalis showed that SAPs have similar efficacy compared to TAP and significantly better efficacy than DAP. On dual-species (SMD = 0.15; CI, -1.00-1.29; P = 0.80) or multi-species (SMD = 0.23; CI, -0.08-0.55; P = 0.15) biofilms, DAP and CH had similar efficacy. Conclusions: Ex vivo evidence showed that antibiotic pastes were either superior or equal to CH. The studied SAPs had considerably higher or similar antibacterial effectiveness compared to DAP, CH, and TAP. Hence, combined antibiotic therapy was not necessarily required for root canal disinfection ex vivo.

Anesthetic efficacy of supplemental buccal infiltration versus intraligamentary injection in mandibular first and second molars with irreversible pulpitis: a prospective randomized clinical trial.

Background: To compare the anesthetic efficacy of supplemental buccal infiltration (BI) (1.7 ml) versus intraligamentary (IL) injection containing 0.4 ml of 4% articaine with 1:100.000 epinephrine after an inferior alveolar nerve block (IANB) with 1.7 ml 2% lidocaine in the first and second mandibular molars diagnosed with irreversible pulpitis (IP). Methods: One hundred subjects diagnosed with IP of either the mandibular first (n = 50) or second molars (n = 50) and failed profound anesthesia following an IANB were selected. They randomly received either the IL or BI techniques of anesthesia. Pain scores on a 170 mm Heft-Parker visual analog scale were recorded initially, before, and during supplemental injections. Furthermore, pulse rate was measured before and after each supplemental injection. During the access cavity preparation and initial filing, no or mild pain was assumed to indicate anesthetic success. The chi-square test, Mann-Whitney U test, and independent samples t-test were used for the analyses. Results: The overall success rates were 80% in the IL group and 74% in the BI group, with no significant difference (P = 0.63). In the first molars, there was no significant difference between the two techniques (P = 0.088). In the second molars, IL injection resulted in a significantly higher success rate (P = 0.017) than BI. IL injection was statistically more successful (P = 0.034) in the second molars (92%) than in the first molars (68%). However, BI was significantly more successful (P = 0.047) in the first molars (88%) than in the second molars (64%). The mean pulse rate increase was significantly higher in the IL group than in the BI group (P < 0.001). Conclusions: Both the IL and BI techniques were advantageous when used as supplemental injections. However, more favorable outcomes were observed when the second molars received IL injection and the first molars received BI.

Comparison of pulse oximeter, cold test, and electric pulp test for assessment of pulp vitality in permanent immature teeth.

INTRODUCTION: Pulp sensitivity tests are commonly used for assessment of pulp vitality. However, indirect assessment of pulp vitality by evaluation of nerve response and subjective nature are the main limitations of these tests. Pulse oximetry is used for assessment of blood oxygen saturation in medicine, and its efficacy for assessment of pulp vitality needs to be evaluated.

The application of selenium nanoparticles for enhancing the efficacy of photodynamic inactivation of planktonic communities and the biofilm of Streptococcus mutans.

OBJECTIVE: Streptococcus mutans is one of the principal causative agents of dental caries (tooth decay) found in the oral cavity. Therefore, this study investigates whether selenium nanoparticles (SeNPs) enhance the efficacy of photodynamic therapy (PDT) against both planktonic communities and the one-day-old biofilm of S. mutans. In this study, the planktonic and 24-h biofilm of S. mutans have been prepared in 96-cell microplates. These forms were treated by methylene blue (MB) and SeNPs and then were exposed to light-emitting diode (LED) lighting. Finally, the results have been reported as CFU/ml. RESULTS: The outcomes demonstrated that MB-induced PDT and SeNPs significantly reduced the number of planktonic bacteria (P-value < 0.001). The comparison between the treated and untreated groups showed that combining therapy with SeNPs and PDT remarkably decreased colony-forming units of one-day-old S. mutans biofilm (P-value < 0.05). The findings revealed that PDT modified by SeNPs had a high potential to destroy S. mutans biofilm. This combination therapy showed promising results to overcome oral infection in dental science.

Evaluation of Residual Debris and Smear layer After Root Canal Preparation by Three Different Methods: A Scanning Electron Microscopy Study.

Introduction: This study investigated the amount of debris and smear layer remaining followed chemomechanical preparation using three systems: ProTaper Universal, reciprocating SafeSider, and hand K-Flexofiles with scanning electron microscope (SEM). Materials and Methods: Sixty-five mandibular molars with mesiobuccal canal curvature (25 to 40°) were extracted and divided into one control group (n=5), and three experimental groups (n=20) according to the preparation method; K-Flexofile, ProTaper Universal and SafeSider instruments. All canals were irrigated with 3 ml of 5.25% sodium hypochlorite solution and 3 mL of 17% EDTA. Subsequently, the canals were irrigated with 5 ml of normal saline. Then the teeth were examined under the scanning electron microscope (SEM). Kruskal-Wallis, Dunn-Q Bonferroni, and Friedman tests were used for statistical analysis of results. Results: To assess the accumulation of debris, statistically significant differences were observed only in the coronal area among ProTaper Universal, SafeSider, K-Flexofile, and the control group. (P=0.029). To evaluate the residual smear layer amount, statistically significant differences were observed only in the coronal and middle areas, following the preparation of the canals using ProTaper Universal, SafeSider, and hand K-Flexofiles and control groups (P=0.019). Conclusions: Based on the present in vitro study, we can declare that the canals were utterly cleaned of debris and smear layer in none of the groups. Manual Flexofile and ProTaper Universal groups result in cleaner canal walls than reciprocal SafeSider, in the coronal and middle thirds.

Comparison of Canal Transportation and Centering Ability of One-G, EdgeGlidePath, and Neolix: A MicroComputed Tomography Study of Curved Root Canals.

AIMS: A glide path is created prior to root canal instrumentation by nickel-titanium (NiTi) rotary files to increase the efficiency and safety of cleaning and shaping. This study aimed to assess root canal transportation in use of different glide path files in curved canals. MATERIALS AND METHODS: 30 sound mesiobuccal root canals of mandibular molars with 20° to 40° curvature were selected and randomly assigned to 3 groups of EdgeGlidePath (EGP, EdgeEndo), One-G (Micro-Mega), and Neolix (Neoniti). The specimens were scanned before and after glide path creation by microcomputed tomography (micro-CT). The pre- and postoperative micro-CT scans were superimposed, and the degree of canal transportation and centering ratio were measured at 1, 3, 5, and 7 mm distances from the apical foramen. Statistical Analysis. The data were analyzed by two-way and one-way ANOVA. RESULTS: The effects of distance from the apical foramen and instrument type and the interaction effect of the two were not significant on the centering ability of the files or canal transportation. CONCLUSION: EdgeGlidePath, One-G, and Neolix files fabricated from the conventional NiTi alloy or heat-treated M-Wire alloy showed similar performance regarding centering ability and canal transportation in glide path preparation in curved canals.

Antimicrobial effects of selenium nanoparticles in combination with photodynamic therapy against Enterococcus faecalis biofilm.

BACKGROUND: Selenium Nanoparticles (SeNPs) were reported as an agent that may enhance the effectiveness of Photodynamic Antimicrobial Chemotherapy (PACT). This in vitro study evaluates the effect of SeNPs on the efficacy of Methylene Blue (MB)-induced PACT against the biofilm formated in 96-well plates and the dentine tubule biofilm of Enterococcus faecalis. METHODS: Chitosan coated SeNPs were synthesized using chemical reduction method and were characterized by Transmission Electron Microscope (TEM) and Dynamic Light Scattering (DLS). Twenty-four-hour biofilms of E. faecalis were developed on 96-well plates and treated with SeNPs, MB, and Light-Emitting Diode (LED). Also, three-week biofilms of E. faecalis were formed on 67 specimens of dentinal tubules, and the antibacterial effects of MB+SeNPs on these biofilms were studied. RESULTS: The average hydrodynamic diameter of SeNPs was 80/3 nm according to DLS measurement. The combined use of MB and SeNPs significantly reduced Colony-Forming Units (CFUs) of one-day-old E. faecalis biofilms in comparison with the control group (P value < 0.05). Besides, combination therapy had the most antibacterial effect on root canal E. faecalis biofilms at both 200 and 400 µm depths of dentine tubules (P value < 0.001). Of note, about 50% of human fibroblast cells survived at a concentration of 128 µg/ml of SeNPs, compared to the control group. CONCLUSION: The results demonstrated that the photodynamic therapy modified by SeNPs could be an effective disinfection alternative to the destruction of E. faecalis biofilms and root canal treatment.

Anaesthetic Efficacy of 4% Articaine in Comparison with 2% Lidocaine as Intraligamentary Injections after an Ineffective Inferior Alveolar Nerve Block in Mandibular Molars with Irreversible Pulpitis: A Prospective Randomised Triple-Blind Clinical Trial.

The objective of the current study was to compare the anaesthetic efficacy of supplemental intraligamentary (IL) injection of 4% articaine with that of 2% lidocaine in the mandibular first and second molars with irreversible pulpitis after an ineffective inferior alveolar nerve block injection (IANB) using the same anaesthetic in a randomised triple-blind clinical trial. Seventy-six adult patients, who were diagnosed with irreversible pulpitis in the mandibular first or second molars, were divided into 2 groups and received IANB randomly. In patients with lip numbness, anaesthesia was evaluated with the cold and electrical pulp (EPT) tests, and if the reported number on EPT was below 100, supplemental IL injection was administered using the same anaesthetic. The teeth were retested after 5 minutes. The Heft-Parker visual analogue scale was used to evaluate pain after IANB and IL injections. Statistical analysis was performed using repeated measures ANOVA, chi-square, and independent-sample and paired-sample t-tests. The results showed that there was no significant difference in the success rates of supplemental IL and IANB injections between articaine and lidocaine. Furthermore, there was no significant difference in the success rates of supplemental IL injection with lidocaine between the mandibular first and second molars. However, there was a significant difference in the success rates of supplemental IL injection with articaine between the mandibular first and second molars. Moreover, supplemental IL injections indicated no significant difference in the anaesthetic efficacy between articaine and lidocaine; nevertheless, they were more effective in the mandibular second molars, especially with articaine.

Effect of Rotary and Reciprocating Instrumentation Motions on Postoperative Pain Incidence in Non-Surgical Endodontic Treatments: A Systematic Review and Meta-Analysis.

OBJECTIVE: A systematic review and meta-analysis were conducted to determine whether there are postoperative pain differences resulting from rotary and reciprocation engine-driven instrumentation motions in non-surgical endodontic treatment or retreatment at 12, 24, and 48 hours. METHODS: Four electronic databases (PubMed, Embase, Cochrane Library, and Scopus) were searched to identify randomised controlled trials that compared the effects of rotary and reciprocating instrumentation motions on postoperative pain. Two authors independently screened the search results, extracted the data, and assessed the quality using the Cochrane risk of bias tool. Due to numerous variables across studies, the random effect inverse variance method for meta-analysis was applied. When significant heterogeneity among studies was present, the random effects multi-variable meta-regression analysis was performed to determine the source of heterogeneity. RESULTS: At all time intervals, the incidence of postoperative pain was higher in the reciprocating instrumentation group, but was not statistically significant. There was no significant difference in the analgesic intake between groups. Meta-regression analysis determined study population sizes as a significant heterogeneous factor, while significance was not observed for preoperative pain or the pulpal diagnosis. CONCLUSION: There was no difference in postoperative pain at 12, 24, and 48 hours after non-surgical root canal treatment and retreatment, using reciprocating or rotary instrumentation motions.

Identification of microorganisms in irreversible pulpitis and primary endodontic infections with respect to clinical and radiographic findings.

OBJECTIVES: The aim of this study was to evaluate the composition of microbiota of irreversible pulpitis and primary endodontic infections with respect to clinical and radiographic findings by performing cultures and 16s rDNA sequencing in Iranian patients. MATERIAL AND METHODS: In this prospective cross-sectional study, samples were collected from 41 root canals for 4 main groups of patients. Bacterial identification was performed by the polymerase chain reaction (PCR) and 16s rDNA sequencing of aerobic and anaerobic cultivable colonies taken from patients' culture plates. Additionally, the presence of 13 bacterial species and 3 nonbacterial species was also explored using PCR and species-specific primers. RESULTS: Sixteen microbial species, 1 fungus (Candida albicans), and 1 virus (Herpes simplex virus) were discovered and isolated. Species with the highest prevalence were Dialister invisus (68.3%), Porphyromonas gingivalis (58.8%), Streptococcus salivarius (58.5%), and Treponema denticola (56.1%). Lysinibacillus fusiformis (19.1%) was detected in the root canals for the first time. Candida albicans was seen in 11 cases (26.8%). Herpes simplex virus (HSV) was seen in 4 patients (9.8%). CONCLUSIONS: Our results suggest that Gram-negative anaerobic oral bacteria are the majority of the microbes in primary endodontic infections. Various combinations of bacterial species were related to different clinical and radiographic conditions. Lysinibacillus fusiformis was detected for the first time in primary endodontic infections. CLINICAL RELEVANCE: The results of this investigation might help clinicians choose to identify suspected endodontic pathogens in the etiology of each form of pulpal and periradicular diseases to determine the best therapeutic measures.