Systematic Review

Size of Master Apical File and Optimal Irrigation of the Apical Zone: A Systematic Review

Anita Aminoshariae, James Kulild

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 424-437

Introduction: To determine what would be the minimal apical diameter for optimal chemomechanical preparation in the root canal system in terms of debridement and/or irrigation delivery, in patients undergoing nonsurgical root canal treatment. Methods and Materials: Randomized controlled clinical trials, cohorts, cross-over studies from peer-reviewed journals published in English from January 1950 to June 2018 which reported outcome in terms of healing, microbial reduction and/or effectiveness of irrigation delivery to the apical third of the root canal system. Two reviewers conducted a comprehensive literature search. There were no disagreements between the two reviewers. The articles that met the inclusion criteria went through a predefined review process. Results: Due to the variety of methodologies and different techniques used to measure outcome for master apical file enlargement, it was not possible to standardize the research data and to perform meta-analysis. Twelve clinical articles were identified that met the inclusion criteria. Conclusions: The overall level of evidence on this topic was moderate (fair). From this systematic review, the majority of the studies collected and referred to recommend sizes higher than #30 as the minimal size in order to adequately prepare the apical region of the root canals. Only 2 out of 12 studies suggested the size #25 as acceptable. From this systematic review it may be concluded that a larger MAF preparation above size 30 aids chemomechanical action.

Keywords: Apical Size; Endodontics; Irrigation; Master Apical Size; Systematic Review

Meta Analysis

Prevalence of Apical Periodontitis in Different Communities: A Meta-Analysis

Shima Sadat Miri, Abbasali Khademi, Zahra Amirkhani, Seyed Mojtaba Amiri, Mohammad Goodarzi, Saber Khazaei

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 438-445

Introduction: The aim of this study was to perform a meta-analysis on the prevalence of apical periodontitis (AP) in different communities to obtain accurate data on its prevalence. Methods and Materials: The prevalence of AP in different communities based on the number of individuals, teeth and root-filled teeth was searched using electronic databases of ISI Web of Knowledge, PubMed, Scopus and also ProQuest and Springer. The Metaprop meta-analysis was done using the software R version 3.3.0 with Meta package. The Logit transformation method and random-effects model were used to calculate the pooled prevalence. Heterogeneity was tested by the Q-test (P<0.1 represented statistical significance), I2 statistics (25%, 50% and 75% represented low, medium and high heterogeneity, respectively) and 2τ (2τ was calculated by DerSimonian-Laird estimator method). Results: A total of 77 studies were identified to qualify for inclusion into this meta-analysis. The prevalence of AP based on the number of individuals, teeth and root-filled teeth with the pooled prevalence was 0.519, 0.0498 and 0.3828, respectively. Conclusions: The results of the present study can be helpful for policy makers to monitor the dental public health demographically and compare it to other communities; they may be able find the strengths and drawbacks of their oral and dental health program.

Keywords: Meta-Analysis; Periapical Periodontitis; Root Canal Therapy

Original Article

Comparison of Antimicrobial Substantivity of Six Root Canal Irrigants against Enterococcus faecalis

Flavio Palazzi, Massimo Del Fabbro, Silvio Taschieri, Zahed Mohammadi, Saeed Asgary, Frédéric Bukiet

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 446-452

Introduction: The antimicrobial substantivity of Mixture of Doxycycline, Citric acid, and Tween 80 (MTAD), Tetraclean, Tetraclean NA, Q-Mix, 2% Chlorhexidine (CHX) and Octenisept was assessed in human root dentine blocks infected with Enterococcus (E.) faecalis. Methods and Materials: A total of 170 dentine tubes were prepared from human maxillary incisors. After crown and apical third removal, cementum was abraded. The remaining center-holed pieces were cut into 4-mm blocks, infected with E. faecalis in Brain Heart Infusion (BHI) broth for 28 days, then randomly divided into 6 experimental groups (n=25) and 2 controls (n=10). At 0, 7, 14, 21 and 28 days, dentine chips were removed from the canals, with sequential round burs with increasing diameters, and collected into freshly prepared BHI broth. After culturing, growing colonies were counted as colony forming units (CFU). Conventional non-parametric tests (Kruskal-Wallis and Mann-Whitney tests) were used to assess intra-group (at different time frames) and inter-group (at each experimental time) differences (P=0.05). Results: Tetraclean yielded the lowest CFU counts (P<0.001) at each observation time. Tetraclean NA and Q-Mix showed better (P<0.001) substantivity than 2% CHX and MTAD (except for Q-Mix versus MTAD at 14 days, P=0.21). Conclusions: In this in vitro study, Tetraclean NA and Q-Mix displayed the best antimicrobial substantivity against E. faecalis after Tetraclean in infected human root dentine. Considering the findings of our study and potential drawbacks of antibiotic-based irrigants, free-antibiotic irrigants may represent viable alternative for final rinse in root canal treatment.

Keywords: Antimicrobial Substantivity; Enterococcus faecalis; MTAD; Qmix; Tetraclean

Introduction: As an attempt to simplify the obturation process and create a tight seal, manufacturers offer gutta-percha (GP) cones matching different sizes of endodontic files. The purpose of this study was to evaluate whether intra-manufacture GP diameters matched the diameters of their corresponding files at different horizontal levels of the canal. Methods and Materials: Twenty files and corresponding GP master cones of Reciproc R 40/0.08 (VDW, Munich, Germany), WaveOne Large (40/0.08) (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper F3 (30/0.09) (Dentsply Maillefer, Ballaigues, Switzerland), and Mtwo (40/0.06) (VDW, Munich, Germany) were examined using laser micrometer (LSM 6000 by Mitutoyo, Japan) with accuracy of 1 nm to establish their actual diameter at D0, D1, D3 and D6. Data were analysed using the independent t-test. The differences were considered as significant for P<0.05. Results: The diameter of GP master cones was significantly larger than the corresponding files at all levels with all the above brands. ProTaper GP diameter were closest to the file diameter at D1 (GP=0.35, File=0.35 mm), and D3 (GP=0.48, file=0.49). Conclusion: This in vitro study showed that within the same manufacturer GP cone diameters do not match the diameters of their corresponding files.

Keywords: Diameter; Gutta-percha Cone; Laser Scan Micrometer; Rotary File; Taper

Histopathological Evaluation of Primary Teeth after Pulp Capping with Calcium-Enriched Mixture and Bioactive Glass

Roza Haghgoo, Saeed Asgary, Roshanak Montazeri

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 457-460

Introduction: Direct pulp capping (DPC) is a conservative vital pulp therapy, which has some limitations in primary dentition. The aim of this study was to evaluate pulpal response of primary teeth after DPC with two biocompatible materials naming calcium-enriched mixture (CEM) and bioactive glass (BAG). Methods and Materials: This study was designed as a randomized clinical trial. After obtaining informed consent, 20 sound primary canines scheduled for orthodontic extraction, were selected. Following mechanical pulp exposure, the exposed site was capped with either CEM cement or BAG and then restored with amalgam. Teeth were extracted after two months and examined histopathologically. Parameters of hard tissue bridge (HTB) formation, its type and pulpal inflammation scores, were compared between the two groups. Data were analysed using the Fisher’s exact test. Results: All CEM specimens showed inflammation scores of 0 (less than 10%). In the BAG group, inflammation scores of 0, 1 and 2 were observed in 7, 2 and 1 specimens, respectively. Fisher’s exact test showed no significant differences (P>0.05). All CEM specimens (100%) formed HTB, which was irregular in all cases. In 7 of 10 teeth in BAG, HTB formed and was irregular. Fisher’s exact test revealed no significant differences between the two groups in this regard (P<0.001). Conclusion: Both CEM and BAG are suitable DPC agents in terms of HTB formation and pulp inflammation scores.

Keywords: Bioactive Glass; Calcium-Enriched Mixture; Direct Pulp Capping; Primary Teeth

A Novel Hybrid Hand Instrumentation Technique for Root Canal Preparation

Iman Bolourchi, Leila Pourmousavi

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 461-468

Introduction: Preparation of root canal system necessitates both enlargement and shaping of the complex root canal space together with disinfection of the easily accessible and hidden areas. The present article introduces a new manual root canal preparation technique and compares it with passive step-back and step-back regarding some items such as shaping efficacy, maintenance of working length and occurrence of procedural accidents. Methods and Materials: This canal preparation technique (Bolourchi Hybrid Technique-BHT) was compared with passive step-back and step-back root through preparation of 30 extracted human mandibular and maxillary molars. Three experienced endodontists evaluated the final radiographies for following items: 1) difficulty of the case 2) shaping efficacy 3) maintenance of working length 4) time of preparation. Two-way ANOVA was used to analyze the data. Multiple comparisons were done using the Tukey’s HSD. Results: Regarding shaping efficacy and maintenance of working length, BHT group showed significantly higher scores and scores for step-back group were significantly the lowest. The difference between BHT group and passive step-back on these items was not significant. No significant differences were found between the techniques in other assessed criteria except for occurrence of procedural accidents which was significantly higher in step-back group. Conclusion: Considering the advantages of this novel technique as well as its comparability to the present routine techniques, it can be considered as an available root preparation technique for teaching in dental schools.

Keywords:Balanced Forced Technique; Hand Instrumentation; Hybrid Hand Instrumentation; Passive Step-Back; Root Canal Preparation; Step-Back


Compressive Strength of Mineral Trioxide Aggregate with and without Disodium Hydrogen Phosphate at Different Mixing Ratios

Hadi Mokhtari, Mehrdad Lotfi, Aysan Mozafari, Mahdi Rahbar, Aydin Sohrabi, Ayda Tadbiri

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 469-473

Introduction: Mineral Trioxide Aggregate (MTA) is a substance with favorable physical-mechanical properties. Disodium hydrogen phosphate(DHP) is sometimes added to MTA to reduce its setting time. Therefore, this study was conducted to evaluate the effect of various ratios of liquid to powder of white MTA (WMTA) and addition of DHP on its compressive strength. Methods and Materials: One hundred and twenty samples were prepared with a two-piece stainless steel mold with a height of 6 mm and a diameter of 4 mm in order to evaluate the compressive strength where WMTA was used in 60 samples and DHP in white MTA composition (DHPWMTA) was used in other 60 samples. The compressive strength of WMTA and DHPWMTA was measured in various ratios of liquid to powder including 50, 60 and 70% and at 24 h and 21 days (n=10). Univariate Analysis of Variance test with SPSS 16 software were used to determine the difference between groups. The level of significance was set at 0.05. Results: The maximum and minimum compressive strength of WMTA groups were 63.25±1.96 (50% ratio and 21 days) and 37.79±1.28 (70% ratio and 24 h), respectively. The maximum and minimum compressive strength of DHPWMTA groups were 63.96±1.40 (60% ratio and 21 days) and 37.37±1.62 (70% ratio and 24 h), respectively. The effect of each of factors (type of material, powder to liquid ratio and time) alone were significant on the compressive strength (P<0.05). However, the interactive effect of three factors (type of material, powder to liquid ratio and time) were not statistically significant on compressive strength (P>0.05). Conclusion: Adding 2.5 wt% of DHP to white MTA increased samples compressive strength. Compressive strength in liquid to powder ratios of 50 and 60% compare to 70% and at 21 days compared to 24 h was high.

Keywords: Compressive Strength; Disodium Hydrogen Phosphate; Mineral Trioxide Aggregate

Efficacy of Two Different Views of Video Demonstration in Teaching Access Cavity Preparation to Third Year Dental Students

Hazem Dabbour, Amy Kia Cheen Liew, Eason Soo, Dalia Abdullah

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 474-480

Introduction: Demonstration of the access cavity preparation procedures to dental students is challenging due to the limited operating field and the detailed nature of the procedures. The aim of this study was to develop and evaluate two different views in video demonstrations used to teach access cavity preparation. Methods and Materials: Two videos of access cavity preparation were filmed, one showing the occlusal view (OV) and one showing the sectional view (SV). Third-year dental students (n=57) who consented to participate in the study were divided into two groups to watch one of the videos. The perception and performance of both groups were compared using the Mann-Whitney U test and Fisher’s exact test. Results: At baseline, group OV (n=29) and group SV (n=28) were not significantly different in terms of operative scores (P=0.330). After watching the videos, the basic understanding of the theories was similar in both groups. However, the SV group responded more positively towards the helpfulness of the video in visualizing the inner anatomy of the tooth and in implementing the procedures (P<0.05). The SV group also completed the exercise within a shorter time (P<0.001). Nevertheless, the quality of the prepared access cavities was not significantly different between groups. Conclusion: Within the limitations of this study, the additional step in sectioning a tooth before demonstration of access cavity preparation seems well worth the effort, offering the novice students advantages in visualizing certain anatomical landmarks and implementing access cavity preparation procedure within a shorter timeframe. Nevertheless, it did not improve the final quality of the preparations.

Keywords: Access Cavity; Dental Education; Endodontics; Root Canal Therapy; Video Demonstration

Effect of Smear Clear and Conventional Root Canal Irrigants on Push-Out Bond Strength of Resilon/Epiphany System

Farzaneh Afkhami, Mona Sadegh, Aidin Sooratgar, Elham Montazeri

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 481-485

Introduction: The aim of the present study is to compare the effect of SmearClear and sodiumhypochlorite (NaOCl), chlorhexidine (CHX) and normal saline (NS) on the push-out bond strength of Resilon/Epiphany system to dentine. Methods and Materials: In this in vitro study; 48 single-rooted teeth were selected and decoronated from the CEJ. Then the specimens were divided into four groups (n=12). The roots were prepared by single length technique using MTwo rotary system. The final irrigations of the canals were done using 2% CHX, normal saline, 5.25% NaOCl or SmearClear. The canals were obturated by Resilon/Epiphany system. The teeth were cut perpendicular to their longitudinal axis and four 1-mm-thick sections were obtained from coronal and mid root regions. The push-out bond strength of Resilon/Epiphany system to dentin were calculated and bond failure patterns were assessed. The data were subjected to two-way analysis of variance and Tukey’s tests. Results: The highest bond strength values were reported for SmearClear and the lowest values for the NS solutions. The effects of irrigant type (P<0.05) and canal area (P<0.0001) on the bond strength of Resilon to dentin were significant (P<0.05). Higher bond strength values were obtained in the mid root areas compared to the coronal regions. In two-by-two comparisons, significant differences in bond strength were found between SmearClear and normal saline (P<0.05) while the other irrigants showed no significant differences (P>0.05). Conclusion: SmearClear solution was able to increase the push-out bond strength of Resilon to the dentin similar to other irrigants (NaOCl and CHX). Therefore, it can be used for the root canal irrigation and smear layer removal in the clinical situations.

Keywords: Push-But Bond Strength; Resilon; Root Canal Irrigation; SmearClear; Smear Layer

Biometric Analysis of C-shaped Root Canals in Mandibular Second Molars Using Cone-Beam Computed Tomography

Negin Riazifar, Kamal Amini, Maryam Zangouyi Boushehri, Mahnaz Sheikhi, Kasra Karamifar

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 486-491

Introduction: The configuration of C-shaped root canals, root canal wall thickness and orientation of the thinnest area using CBCT in mandibular second molars were assessed.  Methods and Materials: Seventy five CBCT scans were evaluated. Axial sections were evaluated to determine the configuration of C-shaped canals in the coronal, middle and apical regions. The root canal path from the orifice to the apex, the thinnest root canal wall and its orientation were all determined. Data were analyzed using one-way ANOVA and post hoc Tukey’s test. Results: The most common configurations were Melton's type I in the coronal and middle and types I and IV in the apical region. The mean thicknesses of the thinnest root canal wall were 1.94±0.43, 1.42±0.57 and 1.10±0.52 mm in the coronal, middle and apical regions, respectively. The lingual wall was the thinnest wall in the coronal, middle and apical regions and it was thinner in the apical than in the middle and coronal regions. The lingual wall was thinner in the middle third of the mesial root compared to the distal root (P<0.05). Conclusion: The lingual wall was the thinnest in C-shaped root canals of mandibular second molars of an Iranian population. Type, number and pathway of canals may vary from the orifice to the apex.

Keywords: Biometric Identification; C-shape Root Canal; Cone-Beam Computed Tomography

Effect of Field of View and Resolution in Detection of Horizontal Root Fractures in CBCT images: An In Vitro Study

Sanaz Sharifi Shoshtari, Nasim Shams, Arash Dabbaghi, Ali Rohani, Makan Dadollahi, Negin Khosravi

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 492-497

Introduction: New cone-beam computed tomography (CBCT) devices are capable of imaging with different resolutions and field of views (FOVs), in which higher resolutions and FOVs impose a higher dose to the patient. This study was an attempt to investigate the detection accuracy from different FOVs and resolutions in detection of horizontal root fractures.  Methods and Materials: Through this experimental study, in five different field of views (FOV) and resolutions (voxel size) of New Tom VGi CBCT (Italy) system was used to scan fifty teeth with horizontal root fractures in half of them. The images were evaluated by four observers (two maxillofacial radiologists and two general dentists) who recorded the presence or absence of horizontal root fractures. The data were analyzed by SPSS 22 software and MacNemar and kappa test were used to compare results with reality. Results: The highest sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy (AZ) were attributed to 8×8 FOV and high resolutions (0.125 mm voxel size) but the difference between sensitivity, specificity, PPV and NPV was not significant. Kappa values for inter-observer agreement between radiologists and general dentists and also intra-observer agreement were in excellent ranges. The highest Kappa in both cases was attributed to 8×8 FOV and high resolutions. Conclusion: There was no significant difference to diagnose of horizontal root fracture between two observer groups and for all of the FOVs and voxel sizes. 

Keywords: Cone-Beam Computed Tomography; Field of View; Horizontal Root Fracture 

Canal Transportation and Centering Ability of Reciproc Blue, WaveOne Gold and ProTaper Next in Simulated Curved Canals

Priscila Florentino Silva, Esio Coelho, Nayane Chagas Carvalho Alves, Silmara Andrade Silva, Fábio Cavalcanti Pereira, Diana Santana Albuquerque

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 498-502

Introduction: The aim of this study was to evaluate the canal transportation and centering ability of ProTaper Next (PTN), WaveOne Gold (WOG) and Reciproc Blue (RCB) in simulated curved resin canals. Methods and Materials: A total of 43 blocks of simulated resin canals with 40° of curvature were prepared to an apical size of 0.02. Flexofile #15 instruments were used along the root canal to reach patency. The blocks were randomly assessed and sequence instruments were used according to each system: PTN, RCB and WOG. The imposition of pre and post instrumentation images were composited and analyzed. The canal transportation and apical centralization were measured using the software GIMP (2.8.4, Creative Commons - Share Alike 4.0 International License, 2013). Data were statistically analyzed using the Shapiro-Wilk test, ANOVA test and Tukey's test. The level of significance was set at 0.05. Results: There were no statistical differences in canal transportation between three systems. The general assessment of three systems presented the RCB group with higher values of centralization and more numbers of centralized points with significant differences between the PTN and RCB groups (P<0.05). Conclusion: In this in vitro study, there were no statistical differences in canal transportation between the RCB, WOG and PTN systems. The lowest transportation was observed in the apical region at 3 mm performed with RCB system, followed by WOG and PTN systems. The RCB demonstrated higher values of centralization and more centralized points when assessed by regions.

Keywords: Canal Transportation; Centering Ability; Reciprocating; Rotary Instrumentation

Cone-Beam Computed Tomographic Evaluation of Radicular Grooves in Maxillary Anterior Teeth in a Selected Iranian Population

Yasamin Ghahramani, Bahare Safarzade Haghighi, Abbas Abbaszadegan, Shole Shahidi

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 503-507

Introduction: The region of maxillary anterior teeth is susceptible to numerous anomalies such as radicular groove (RG). RG usually begins by the cingulum of the tooth and proceeds to the root surface in various lengths and depths. This anomaly can prone the tooth to periodontal and endodontic pathosis. The aim of this study was to evaluate the prevalence of RG in maxillary anterior teeth in an Iranian population using cone-beam computed tomography (CBCT). Methods and Materials: A total of 552 CBCT images of maxillary anterior teeth were randomly selected from the archive of a radiology clinic in Shiraz, Iran. Eighteen hundred maxillary anterior teeth met the inclusion criteria. The variants including patient's gender, tooth type, presence or absence and unilateral or bilateral incidence of RGs, their types, and mesiodistal location of RGs were analyzed using the Chi-square test. Results: RGs were diagnosed in 0.5% of central incisors, 2.6% in lateral incisors and 0.16% in canines. The prevalence of RGs in maxillary incisors and maxillary anterior teeth were calculated 1.58% and 1.11%. Statistical analysis showed that there was no significant relationship between gender and the presence, symmetry and location of RGs, but different tooth types had significant differences in the presence of RGs. Conclusion: In this cross sectional study the prevalence of RG had higher frequency in lateral incisors in comparison with canines and central incisors. CBCT is very useful in RG cases and is beneficial in RG diagnosis and treatment planning.

Keywords: Cone-Beam Computed Tomography; Dental Anomalies; Radicular Groove

Comparative Evaluation of Clinical and Radiographic Success of MTA and Propolis in Pulpotomy of Primary Molars

Samaneh Aghazadeh, Roza Haghgoo, Majid Mehran, Fatemeh Kadkhodaei

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 508-514

Introduction: In this study, the results of using MTA and propolis in the pulpotomy of primary molar teeth are evaluated clinically and radiographically. Methods and Methods: A total of 25 healthy 4 to 8 year old children each having two carious primary molar teeth in one arch, based on inclusion criteria were selected. In each child, random assignment of the pulpotomy medicaments was done as follows: Group I, MTA in one side; Group II, Propolis in another side. All the pulpotomized teeth were evaluated at 3, 6, and 9 month clinically and radiographically, based on the scoring criteria system. Finally data was analyzed using GEE analysis. Results: Results showed that the effects of treatment and time on two scores were tested. Based on the results of this model, the chances of having clinical score 2, versus score 1 are about 2.7 times higher in MTA treatment than in propolis (P=0.001). Similarly, the chance of having a clinical score 2 relative to its one, at 9th month is approximately 6.8 times higher than the 3th month (P=0.000) and at 6th month is approximately 2.8 times higher than the 3th month (P=0.005). The chance of having higher scores of radiographies in treatment of propolis is approximately 6.5 times than that of MTA (P=0.000). Also, the chance of having higher scores of radiographic index at 6th month is approximately 5 times and at 9th month is approximately 27 times more than the 3th month (P=0.00). Conclusions: Based on the results of this experimental study, teeth treated with MTA showed more suitable clinical and radiographic results as compared to propolis at 9 months follow-up.

Keywords: Mineral Trioxide Aggregate; Primary Teeth; Propolis; Pulpotomy

Biocompatibility of Acetazolamide and Its Association with Calcium Hydroxide in Rat Subcutaneous Tissue

Carolina Lazarotto, Aline Cristina Batista Rodrigues Johann, Everdan Carneiro, Patrícia Vida Cassi Bettega, Vânia Portela Ditzel Westphalen

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 515-521

Introduction: The aim of this study was to evaluate the biocompatibility of acetazolamide and its association with the calcium hydroxide in rat subcutaneous tissues as an intracanal medication for an avulsed tooth. Methods and Materials: Three medications with acetazolamide base were evaluated: group 1 liquid acetazolamide associated with calcium hydroxide powder (LACH); group 2 liquid acetazolamide (LA); and group 3 acetazolamide powder associated with physiological saline (PAPS). The calcium hydroxide associated to physiological saline represented the control group. The medications were implanted in subcutaneous tissues of thirty-nine male rats for 7, 15 and 45 days; after surgery the animals were sacrificed and the sections were stained with hematoxylin and eosin to be evaluated qualitatively or semi-quantitatively with an optical microscope. The inflammation intensity and type of inflammatory cells and the repair process, were assessed. The obtained data were statistically compared through the Kruskal-Wallis test conducted at the 5% level of significance. Results: On the seventh day, there was statistically significant difference between PAPS and LA, in relation to the number of neutrophils (P=0.0016). There was a statistically significant difference in the total number of inflammatory cells in PAPS compared to LACH (P=0.0038) on the fifth day. The total number of inflammatory cells from PAPS was significantly higher in relation to LACH (P=0.0038), as well as LA from LACH (P=0.0038) on forty fifth day. A statistically significant reduction in the value of lymphocytes was also observed in LACH (P=0.0072) and LA (P=0.0010) groups in the same period. Conclusion: The results of this animal study suggest that the association of the liquid acetazolamide with the calcium hydroxide promoted an inflammation reduction and a faster repair process than in the LA and PAPS groups evaluated in 15 and 45 days. 

Keywords: Acetazolamide; Calcium Hydroxide; Root Resorption

Effects of Two Calcium Silicate Cements on Transforming Growth Factor-β1 Secretion from Human Dental Pulp Stem Cells

Salma Omidi, Mehdi Bagheri, Mozhgan Fazli, Naghmeh Ahmadiankia

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 522-527

Introduction: The aims of this in vitro study were to evaluate the effects of two calcium silicate based cements, Calcum-enriched Mixture (CEM) and Biodentine  on proliferation of human dental pulp stem cells (hDPSCs) and the effects of proposed cements on the secretion of Transforming Growth Factor β1 (TGF-β1). Methods and materials: The cell cultures of human Dental Pulp Stem Cells (hDPSCs) at passage 3-5 were treated with various dilutions (1/1, 1/2, 1/4, 1/8, 1/16, and 1/32) of CEM and Biodentine extracts to assess the cell proliferation using 3-(4, 5-dimethylthiazol-2-Y1)-2, 5-diphenyltetrazolium brovide (MTT) assay after 48 and 72 h. The amount of TGF-β 1 secretion were estimated after 72 h using an enzyme-linked immunosorbent assay. Data were analyzed using the one-way analysis of variance (ANOVA) followed by the Dunnett’s test at the level of significance set at 0.05. Result: CEM showed the highest rates of cell proliferation compared to Biodentine after 72 h (P<0.05). A greater amount of TGF-β1 was secreted by hDPSCs treated with Biodentine compared to CEM (P<0.05). These differences were statistically significant (P<0.05). Conclusion: In this in vitro study hDPSCs showed more proliferation capacity with CEM rather than Biodentine and TGF-β1 secretion rate in Biodentine was higher.

Keyword: Biodentine; Calcium-Enriched Mixture; Human Dental Pulp Stem Cells; Proliferation; Transforming Growth Factor-β

Effect of Topical Epigallocatechin-Gallate on Lipopolysaccharide-induced Pulpal Inflammation in Rat Models

Kun Ismiyatin, Soegeng Wahluyo, Djoko Agus Purwanto, Retno Pudji Rahayu, Adioro Soetojo, Indri Safitri Mukono

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 528-533

Introduction: Pulpal inflammation can be marked by an increase in tumor necrosis factor-α (TNF- α), malondialdehyde (MDA) and calcitonin gene-related peptide (CGRP) level. Epigallocatechin-3-gallate (EGCG) demonstrates the ability to reduce cytokine expression, influence immune receptors, reduce inflammation, neutralize reactive oxygen species (ROS) and to inhibit pain conduction. The present research aimed to determine the anti-inflammatory, antioxidant and pain conduction inhibition of topical EGCG hydrogels in Lipopolysaccharide (LPS)-induced pulpal inflammation in rats. Methods and Materials: A total of 28 male Wistar rats were divided equally into four groups. The negative control group (N) received no treatment, while the positive control group (C) and the other two treatment groups (T1, T2) were induced with LPS for 6 h, followed by the application of topical polyethylene glycol (PEG) hydrogels for C group, 25 ppm EGCG hydrogels for T1 group and 75 ppm EGCG hydrogels for T2 group, before being filled with glass ionomer cement (GIC). After 24 h, PEG and EGCG were reapplied and refilled with GIC for 24 h. The pulp tissue samples were examined by means of immunohistochemistry (IHC) to identify TNF-α, MDA and CGRP expression. All the data obtained was analyzed with one-way analyses of variance (ANOVA) test. Results: The T1 and T2 groups showed a significant decrease in TNF-α and CGRP expression compared to the control group, but there was no significant decrease in MDA in either group (P<0.05). Conclusion: Based on the results of this study, topical application of 75 ppm EGCG hydrogels to the tooth cavities with six hours of pulpal inflammation has the optimal result in reducing the expression of TNF-α and CGRP, but not of MDA.

Keywords: Calcitonin Gene-related Peptide; Epigallocatechin-3-Gallate; Malondialdehyde; Pulpal Inflammation; Tumor Necrosis Factor-α

Comparison of Antibacterial Effect of Four Irrigation Solutions in Primary Root Canal Infections: A Clinical Study

Sedigheh Khedmat, Nooshin Fakhari, Mohammad Emaneini, Reza Beigverdia

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 534-539

Introduction: Reducing the bacterial count from the root canal system is one of the main stages in root canal treatment. The aim of the present clinical study was to compare the antibacterial effect of four intracanal irrigants in primary endodontic infections using both microbiological culture and quantitative Real-time Polymerase Chain Reaction (qRT-PCR) technique. Methods and Materials: Forty patients with primarily infected single rooted premolars were selected and then randomly divided into 4 groups according to the intra canal irrigant used: 5.25% Sodium hypochlorite (NaOCl), Hypoclean (Ogna Laboratori Farmaceutici, Muggiò, Italy), 2% chlorhexidine glouconate (CHX) and CHX-Plus (Vista Dental Products, Racine, WI, USA). Samples were collected before and after chemomechanical preparation and were evaluated by bacterial culture and RT-PCR technique for Enterococcus faecalis and Fusobacterium nucleatum. Data analyzed by repeated measured ANOVA. The significance level was set at 0.05. Results: Four irrigation solutions significantly reduced the total numbers of cultivable bacteria (P<0.05). No statistically differences were found among the antibacterial effects of 5.25% NaOCl (99.93%), Hypoclean (99.94%), 2% CHX (99.77%) and CHX-Plus (99.83%) in reducing cultivable bacteria. Enterococcus faecalis and Fusobacterium nucleatum were no longer detected after preparation using four irrigants (100% reduction). Conclusions: All tested irrigants including 5.25% NaOCl, Hypoclean, 2% CHX and CHX-Plus significantly reduced the number of bacterial colonies in primary endodontic infections.

Keywords: CHX-Plus; Endodontic Infection; Enterococcus faecalis; Fusobacterium nucleatum; Hypoclean

Influence of Immediate Coronal Restoration Placement on Microhardness of CEM Cement: An In Vitro Study

Maryam Kazemipoor, Maedeh Tamizi

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 540-544

Introduction: Coronal restoration could affect the setting reaction of the underlying CEM cement. The aim of the present study was to evaluate the effect of immediate coronal restoration placement on the subsurface microhardness of CEM cement. Methods and Materials: In 50 extracted human mandibular molars, access cavities were prepared and CEM cement was placed in the pulp chamber at a 3-mm thickness. Samples were divided into ten groups (n=5). CEM cement was placed and after 10 min, two groups were restored with Zonalin temporary restoration and eight groups were restored with glass ionomer cement (GIC), resin modified glass ionomer (RMGI), resin based composite and amalgam respectively. Vickers microhardness number (VHN) of CEM cement was measured in two time intervals (7- and 21-days). Data was analyzed with SPSS and two-way analysis of variance and Bonferroni tests. Level of significance was set at the 5%. Results: The mean VHN of CEM cement showed statistically significant differences only between Zonalin and amalgam groups (P=0.021). There were also significant differences considering the effect of time (P=0.042) and material (P=0.046). Although the effect of time-material on the microhardness values showed no statistically significant differences (P=0.636). Conclusion: Based on the results of the present study, immediate placement of final restorations affects the setting reaction in underlying CEM cement. Therefore, sufficient moist curing and hydration should be guaranteed before the placement of the coronal restoration.

Keywords: Calcium-enriched Mixture; CEM Cement; Dental Restoration; Setting Time; Vickers Microhardness

Cone-Beam Computed Tomographic Evaluation of Artifact Effects of Three Different Sealers

Maryam Tofangchiha, Marjan Bolbolian, Sahar Rahrovan, Monirsadat Mirzadeh, Neda Hajihassani

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 545-548

Introduction: Cone-beam computed tomography (CBCT) is one of the most important diagnostic tools in maxillofacial imaging. Nowadays different sealers are used in root canal therapy and some of them can create artifact in CBCT images. The aim of this study was to evaluate the effect of different sealers including AH-26, Diadent, and Anyseal in creation of artifact bands in the CBCT images based on voxel size. Methods and Materials: A total of 44 single rooted extracted teeth were selected. The canals were prepared by crown-down technique. All teeth were manually filed up to master apical file (MAF) size 45 and 1 mm shorter than the apical foramen. The teeth were divided into 4 equal groups. The canals were filled with gutta-percha and either of sealers AH-26, Diadent or Anyseal by lateral condensation technique. The control group were filled just with gutta-percha without any sealer. The CBCT images were taken in voxel sizes of 0.3 and 0.15. The Fisher exact and McNemar tests were used for statistical analysis. Results: Although, the control group had the lowest ratio of presence to absence of artifact, the ratio of presence to absence of artifact in voxel size of 0.3 and 0.15 mm were significantly lower in Anyseal than AH-26 (P=0.031, P=0.020) and Diadent (P=0.001, P=0.002). No significant difference was detected between two voxel sizes (P>0.05). Conclusion: In this in vitro study, all evaluated sealers induced artifacts in the CBCT images. Anyseal sealer had the lowest artifact in both evaluated voxel sizes.

Keywords: Artifacts; Canal Sealer; Cone-Beam Computed Tomography; Root Canal Filling Material; Root Fracture

Incidence of Dentinal Crack Formation Using ProTaper Universal and WaveOne Systems in Straight and Curved Root Canals

Nahid Mohammadzade Akhlaghi, Abbas Delvarani, Vanousheh Norouzi, Pooneh Mohebbi, Naghmeh Meraji

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 549-553

Introduction: This study aimed to compare dentinal micro crack formation following root canal instrumentation with ProTaper Universal (PTU) and WaveOne (WO) rotary systems in straight and curved root canals. Methods and Materials: One hundred mesiobuccal (MB) straight and curved canals of mandibular molars meeting inclusion criteria were divided into two control (n=10) and four experimental groups (n=20). After mounting the teeth and simulating the periodontal ligament, all the MB canals were coronally flared using Gates-Glidden drills #3 and 2 respectively. Then, in the experimental groups, the canals were instrumented with either PTU files (Sx, S1, S2, F1, F2), or Primary WO (25/0.08). Afterwards, roots were horizontally sectioned at 2, 4, and 6 mm from the apices, and evaluated under a microscope under 20× magnification. Data were analyzed with the Chi-Square and Kruskal-Wallis tests. The significance level was set at 0.05. Results: The control groups showed no cracks. There was no significant difference between the two systems in the straight root canals (P>0.05). But in the curved root canals, PTU produced significantly more cracks (P<0.05) with the complete crack type which was dominant (P=0.013) compared to WO. Conclusions: This in vitro study showed that in curved root canals, instrumentation with reciprocal WO system may be safer than full rotational PTU instruments regarding crack formation.

Keywords: Crack; Dentin; Instrumentation; Reciprocating; Root Canal Preparation


Comparison of Flexural Strength of Mineral Trioxide Aggregate, Calcium-enriched Mixture and BioAggregate

Negar Moghaddam, Morteza Ebadi Jokandan, Masoud Nouri-Vaskeh, Amin Salem Milani

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 554-558

Introduction: The aim of this study was to compare the flexural strength of mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM), and BioAggregate (BA). Methods and Materials: In this study, the flexural strength of materials was measured using a 3-point bend test. After being prepared, MTA, CEM, and BA were inserted into the intra-putty molds using amalgam plugger. The specimens were covered with a sponge wetted with synthetic tissue fluid (STF) and incubated for 96 h. They were then subjected to a 3-point bend test using Universal Testing Machine. The Kruskal-Wallis and Mann-Whitney U tests were used to compare flexural strength in groups. In this study, P<0.05 was considered as the significant level. Results: There were significant differences between the three groups in terms of the flexural strength (P<0.001). The mean flexural strength in the BA, CEM, and MTA groups were 27.32±2, 9.09±1.16, and 10.25±1.6, respectively. Pairwise comparison showed significant differences between the three groups. Conclusion: This in vitro study showed that BA has the highest and CEM has the lowest flexural strength.

Keywords: BioAggregate; CEM Cement; Flexural Strength; Mineral Trioxide Aggregate


Effect of Endodontic Irrigants and Medicaments Mixed with Silver Nanoparticles against Biofilm Formation of Enterococcus faecalis

Yasamin Ghahramani, Fariba Yaghoubi, Ramin Motamedi, Akram Jamshidzade, Abbas Abbaszadegan

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 559-564

Introduction: The aim of this study was to evaluate the effectiveness of chlorhexidine (CHX), sodium hypochlorite (NaOCl), calcium hydroxide (CH) and double antibiotic paste (DAP) mixed with silver nanoparticles (AgNPs) against Enterococcus faecalis. Methods and materials: Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and biofilm formation inhibition (after 72 h) of the experimental substances alone or mixed with AgNPs were measured against E. faecalis using microtiter plate method. Bacterial cultures turbidity was measured using a spectrophotometer. All procedures were performed in triplicates. Results: The MIC values for CHX, NaOCl, CH and DAP were equal to 0.012, 1.25, 1.6 and 0.156 mg/mL, and their MBC’s were 0.025, 2.5, 0 and 0.625 mg/mL. After mixing them with AgNPs, the MIC’s for CHX, NaOCl, CH and DAP were reduced to 0.0032, 0.158, 0.2 and 0.0391 mg/mL, while their MBC’s were reduced to 0.0064, 0.0632, 0.401 and 0.0156 mg/mL. Biofilm formation inhibition occurred in higher dilutions of all irrigants and medicaments as they were mixed with Ag NPs. Conclusions: Adding AgNPs resulted in an increased antimicrobial activity at the tested dilutions for all experimental substances. More investigations in in vivo conditions are required to confirm the results of this study.

Keywords: Calcium Hydroxide; Chlorhexidine; Double Antibiotic Paste; Enterococcus Faecalis; Silver Nanoparticles; Sodium Hypochlorite

Evaluation of Canal Transportation after Using Different Types Rotary Glide Path Files

Linz Ali Shalan, Hussain F Al-Huwaizi

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 565-568

Introduction: Canal transportation is a common problem caused by rotary instruments. The purpose of the present study was to evaluate root canal transportation after using WaveOne Gold Glider, ProGlider, Path File and K-file. Methods and materials: Forty resin blocks with L-shaped canals were divided into four groups (n=10). Group 1; canals were prepared with WaveOne Gold Glider, group 2; ProGlider, group 3; Path Files and group 4; #10, #15, and #20 stainless steel manual K-Files. Pre- and post-instrumentation photographic images were superimposed and resin removed from the inner and outer surfaces of the root canal was calculated through 3 points at 3, 6 and 9 mm from the end of canal which represented canal transportation. All data were analyzed by one way ANOVA test. The level of significance was set at 0.05. Results: Statistical analysis by one-way ANOVA test revealed that there was no significant differences (P>0.05) between the tested files in canal transportation in apical, middle and coronal third. The last amount of canal transportation happened at the apical third in WaveOne Gold Glider group. Conclusions: This in vitro study showed that using WaveOne Gold Glider files lead to less canal transportation especially in the apical third area with less significant differences with ProGlider, PathFiles and K-File.

Keywords: Canal Transportation; Glide Path File; Resin Block; WaveOne Gold Glider

Case Report

Double Antibiotic Paste for Management of External Inflammatory Root Resorption

Sedigheh Sabbagh, Alireza Sarraf Shirazi, Hassan Torabzadeh

Iranian Endodontic Journal, Vol. 13 No. 4 (2018), 24 October 2018 , Page 569-572

External inflammatory root resorption (EIRR) is one of the common complications following dental trauma which when remained untreated, may lead to tooth loss. Successful treatment outcomes depend on elimination of bacteria from root canal system and apical sealing. This case presents the endodontic management of an EIRR that was nonresponsive to calcium hydroxide (CH) therapy. An 11-year-old boy was referred for management of a traumatized maxillary central incisor. Tooth #8 was symptom-free, nonresponsive to vitality pulp tests and had an immature root with sever EIRR. Using chemomechanical debridement and CH dressing, the treatment was initiated. The tooth was remained asymptomatic; however, after five weeks the size of periradicular lesion increased and intracanal exudate was present, signifying a resistant endodontic infection. In second appointment, double antibiotic paste (DAP; ciprofloxacin/metronidazole) was applied to the canal. Eight weeks later, the tooth continued to be asymptomatic and the size of the lesion decreased. Finally, the root canal was entirely obturated with calcium-enriched mixture (CEM). At 18-month follow-up, the tooth was asymptomatic/functional, EIRR did not further progress and tooth discoloration was not observed. Based on the results, DAP has the potential to be used to manage the CH-resistant endodontic infection. Furthermore, CEM root filling/sealing seems to be an applicable choice in EIRR management.

Keywords: Antibiotics; Calcium-Enriched Mixture; CEM Cement; Dental Trauma; Endodontics; Intracanal Medicament; Root Resorption