Systematic Review


Effect of Obturation Techniques on the Quality of Root Canal Fillings: A Systematic Review and Meta-analysis of in Vitro Studies

Gabriel Barcelos Só, Natália Backa Abrahão , Theodoro Weissheimer, Tathiane Larissa Lenzi, Marcus Vinicius Reis Só , Ricardo Abreu Rosa

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 61-74
https://doi.org/10.22037/iej.v19i2.40210

Introduction: The current study aimed to compare the quality of root canal obturation performed with cold lateral condensation with other obturation techniques. Materials and Methods: Diverse Search was conducted using six electronic/academic databases following PICOS (i.e. population, intervention, control, outcomes, and study design) strategy: (P) Extracted mature permanent teeth; (I) Obturation techniques except for cold lateral condensation; (C) Cold lateral condensation tyechnique; (O) Quality of root canal obturation; and (S) In vitro studies assessing parameters using micro-computed tomography. The statistical method used for the meta-analyses was the “inverse variance DerSimonian-Laird test”. The heterogeneity data was calculated using the T2, Cochran Q test, and I2 statistics. Results: Fifteen studies were included for the final analysis; one had a low risk of bias, eight a moderate risk, and six a high risk of bias. Ten studies were selected for meta-analyses; three studies comparing cold lateral condensation with carrier-based gutta-percha techniques [P=0.96; mean difference (MD)=-0.02; confidence interval (CI): (-0.77, 0.73); I2=21%]; three comparing cold lateral condensation with single-cone techniques [P=0.75; MD=-0.39; CI: (-2.77, 1.99); I2=92%]; two comparing cold lateral condensation and thermo-plasticized injectable techniques [P=0.37; MD=5.91; CI: (-7.13,18.94); I2=99%]; and five comparing cold lateral condensation with warm vertical condensation techniques [P<0.0001; MD=5.29; CI=(2.84, 7.74); I2=92%]. The overall effect reported significant results [P=0.0003; MD=2.69; CI=(1.23, 4.16); I2=96%]; favoring fewer voids and gaps for the other used obturation techniques. Conclusions: Cold lateral condensation and single-cone techniques presented no statistical differences. Nonetheless, Warm vertical condensation technique had better results compared to cold lateral condensation.

Effect of Foraminal Enlargement on Periapical Healing in Necrotic Teeth: A Systematic Review

Gustavo Oliveira Campos, Alexandre Henrique dos Reis Prado , Isabella Figueiredo de Assis Macedo, Isabella da Costa Ferreira , Gabriela da Costa Ferreira , Francine Benetti, Isabella Faria da Cunha Peixoto , Ana Cecília Diniz Viana

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 75-84
https://doi.org/10.22037/iej.v19i2.44037

Introduction: Foraminal Enlargement (FE) is a cleaning performed in the apical-most region of the tooth, in order to optimize root disinfection. This systematic review evaluated the influence of FE during root canal treatment on bacterial reduction and repair of the periapical lesion. Materials and Methods: Searches in PubMed/MEDLINE, Scopus, Cochrane Library, Web of Science, Embase, Scielo, Lilacs and OpenGrey were performed until January-2024. Ex vivo and in vivo studies evaluating the effects of FE in the bacterial reduction and repair of the periapical lesion were included, respectively, followed by risk of bias assessment (modified version of Joanna Briggs Institute’s for ex vivo studies and Systematic Review Centre for Laboratory animal Experimentation’s risk of bias tools for in vivo studies). The meta-analysis was not feasible and a qualitative summary for each outcome was provided. Results: Of 950 studies, 2 in vivo studies were eligible, using animal models with infected teeth. Of these two, periapical repair was evaluated with hematoxylin-eosin stain, and FE improved periapical healing. Regarding ex vivo studies, 3 were eligible, using extracted human teeth. The inoculations in ex vivo models were performed with Enterococcus (E.) faecalis, and FE reduced E. faecalis in the ex vivo models. Conclusions: Foraminal enlargement seems to increase bacterial reduction within the root canal, and provide major periapical tissue repair on the histological analysis in animal studies. However, caution is necessary when translating these results to the clinical environment.

Review Article


Artificial Intelligence in Endodontics: A Scoping Review

Saeed Asgary

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 85-98
https://doi.org/10.22037/iej.v19i2.44842

Artificial intelligence (AI) is transforming the diagnostic methods and treatment approaches in the constantly evolving field of endodontics. The current review discusses the recent advancements in AI; with a specific focus on convolutional and artificial neural networks. Apparently, AI models have proved to be highly beneficial in the analysis of root canal anatomy, detecting periapical lesions in early stages as well as providing accurate working-length determination. Moreover, they seem to be effective in predicting the treatment success next to identifying various conditions e.g., dental caries, pulpal inflammation, vertical root fractures, and expression of second opinions for non-surgical root canal treatments. Furthermore, AI has demonstrated an exceptional ability to recognize landmarks and lesions in cone-beam computed tomography scans with consistently high precision rates. While AI has significantly promoted the accuracy and efficiency of endodontic procedures, it is of high importance to continue validating the reliability and practicality of AI for possible widespread integration into daily clinical practice. Additionally, ethical considerations related to patient privacy, data security, and potential bias should be carefully examined to ensure the ethical and responsible implementation of AI in endodontics.

Original Article


Propolis-enhanced Calcium Hydroxide Combination for Direct Pulp Capping: Impact on Oxidative Stress Markers in Wistar Rat Teeth

Ira Widjiastuti, Sri Kunarti , Evri Kusumah Ningtyas , Ayu Rafania Atikah , Khadijah Fauzi Basalamah, Amelia Evita Puspita , Novelia Ayu Widianti , Tengku Natasha Eleena binti Tengku Ahmad Noor

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 99-104
https://doi.org/10.22037/iej.v19i2.42269

Introduction: This study explored the effects of propolis extract calcium hydroxide (Ca(OH)2) combination on malondialdehyde and superoxide dismutase expression in dental pulp, aiming to assess its potential as a direct pulp capping material. Materials and Methods: Thirty male Wistar rats were randomly assigned to three groups. Mandibular molar teeth were prepared using a low-speed round bur. In Group I, no material was applied; in Group II, teeth were treated with Ca(OH)2; and in Group III, teeth were treated with Propolis extract-Ca(OH)2, followed by Cention N filling. Immunohistochemistry was conducted on pulp tissue samples obtained on the third and seventh days post-treatment to assess malondialdehyde and superoxide dismutase expression. Statistical analyses included the Shapiro-Wilk test, Levene test, ANOVA, and Tukey’s HSD. Results: The samples treated with propolis extract-Ca(OH)2 combination exhibited significantly lower malondialdehyde expression on both days compared to samples treated with Ca(OH)2 (P<0.05), indicating reduced oxidative stress. Superoxide dismutase expression in the propolis extract-Ca(OH)2 group was higher (P<0.05), suggesting an enhanced antioxidant activity. The control group showed intermediate results. Statistical analyses confirmed significant differences between groups for both malondialdehyde and superoxide dismutase expressions (P<0.05). Conclusion: The study suggests that the propolis extract-Ca(OH)2 combination holds promise for direct pulp capping applications by minimizing oxidative stress and promoting antioxidant defense mechanisms in dental pulp.

Influence of Passive Ultrasonic Irrigation of the Photosensitizer Used in Photodynamic Therapy on Microbial Reduction in the Root Canal System: An in Vitro Study

Danuza Santos Silvestre de Almeida, Alexandre Sigrist De Martin, Daniel Guimarães Pedro Rocha, Carlos Eduardo Fontana, Rina Andréia Pelegrine, Carlos Eduardo da Silveira Bueno, Sérgio Luiz Pinheiro

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 105-111
https://doi.org/10.22037/iej.v19i2.36934

Introduction: The success of endodontic treatment is based on microbial reduction promoted by the interaction of chemical and mechanical procedures. Photodynamic therapy (PDT) is used as an adjunct to conventional treatment, with significant microbial reduction. This study aimed to evaluate the influence of passive ultrasonic irrigation (PUI) of the photosensitizer (PS) used in PDT on microbial reduction in the root canal system. Materials and Methods: Forty-five mesiobuccal root canals from extracted human mandibular molars that were inoculated with standard strains of Enterococcus faecalis, Candida albicans, and Streptococcus mutans for 21 days were selected. The root canals were prepared using the ProTaper Next system and randomly divided into 3 groups (n=15): 1) PDT: PDT alone; 2) PUI+PDT: PUI followed by PDT; and 3) PUI/PS+PDT: PUI of the PS followed by PDT. Microbiological samples were collected from the canals before and after using the protocols described above. The data were analyzed by analysis of variance (Tukey’s test) at a significance level of 5%. Results: Microbial counts before PDT, PUI+PDT, and PUI/PS+PDT did not differ significantly (P>0.05), showing methodological standardization in the microbial contamination of the root canal system. There was a significant reduction in microbial counts after PDT (61.05%), PUI+PDT (65.04%), and PUI/PS+PDT (68.58%) (P<0.01), but with no statistically significant difference between the three groups (P>0.05). Conclusion: Based on the present findings, it was concluded that the combination of PUI with PDT or PS activation did not influence microbial reduction achieved by PDT alone.

Filling Material Bond Strength to Dentin Is Positively Influenced by the Agitation of Endodontic Final Irrigating Solutions

Alessandra Aparecida da Silva Trandafilov, Renata Grazziotin-Soares , Amanda Palmeira Arruda Nogueira, Etevaldo Matos Maia-Filho, Meire Coelho Ferreira, Rudys Rodolfo de Jesus Tavarez, José Bauer, Ceci Nunes Carvalho

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 112-119
https://doi.org/10.22037/iej.v19i2.34108

Introduction: The final step of irrigation has been considered to of increase the bonding strength of filling material to dentin. This study investigated the impact of three final-step irrigation methods on the endodontic sealer bond strength to dentin by using a micro push-out test. Materials and Methods: Palatal roots of human maxillary molars were cleaned and shaped and randomly divided in six groups (n=15) according to the final-step irrigation method and the type of root canal sealer used. The solutions used for the final-step irrigation were 17% ethylenediaminetetraacetic acid and 2.5% sodium hypochlorite, which underwent three methods: 1) syringe-needle irrigation/conventional, 2) passive ultrasonic irrigation, and 3) XP-endo Finisher agitation. The root canal sealers used were: EndoSequence BC Sealer, and AH-Plus sealer. Roots were obturated with the single cone technique and then, cross-sectioned in 2-mm-thick slices (3 slices from each root). Push-out test was performed on the sliced specimens (cervical, middle, and apical thirds) with a universal testing machine. Bond strength values were recorded in megapascal (MPa). Subsequently, each specimen was longitudinally split to verify the type of failure. Data analysis was performed using Johnson transformation, three-way analysis of variance, Tukey’s post-hoc tests, and the partial Eta squared test. Results: There were significant differences in bond strength between the sealers [AH: 4.46±2.24 and BC: 3.47±2.19 MPa (P<0.001)]; between final-step irrigation methods [passive ultrasonic irrigation: 4.52±2.25, XP-endo Finisher: 3.93±3.93 and syringe-needle irrigation/conventional: 3.37±2.51 MPa (P<0.001)], and between the root canal thirds represented by the sliced specimens [cervical: 5.45±2.39, middle: 4.14±1.99 and apical: 2.30±1.30 MPa (P<0.001)]. The interaction between the variables had no significance (P>0.05). Conclusion: Agitation of the final irrigating solution may improve the bonding of the sealer to canal walls. AH-Plus sealer had the highest bond strength. The bond strength reduced significantly towards the apical third.

Case Report


Revascularization of a Previously Treated Mandibular First Molar with Open Apices: A Case Report

Mojgan Feli , Anita Taheri , Mahgol Mehrabani

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 120-123
https://doi.org/10.22037/iej.v19i2.43321

In this case report, the regeneration method was used to treat the previously treated first molar, which presented with symptoms of pain during chewing and secondary acute apical periodontitis. Due to the importance of preserving the patient's permanent teeth in order to maintain optimal space and function, the regeneration treatment was performed in two visits and according to the American Association of Endodontists (AAE) guidelines. The continuation of tooth root development, healing of periapical radiolucency and positive response to sensibility test (cold test) were observed during follow-up radiographs at intervals of 6 months, 1 year & 2 year.

Successful Management of a Rare Distant Endodontic Lesion: A Case Report

Mohammad Jafar Eghbal; Ardavan Parhizkar , Saeed Asgary

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 124-129
https://doi.org/10.22037/iej.v19i2.44860

The current case report aims to document a rare presentation of a distant odontogenic lesion of a 35-year-old male patient with mild clinical discomfort in the mandibular right first molar; exploring the diagnostic and therapeutic intricacies of an uncommon distant endodontic pathosis ultimately resolved through meticulous nonsurgical retreatment. Despite a normal oral examination, diagnostic radiography revealed a suboptimal root canal treatment and apical lesions surrounding mesial- and distal-root apices; including a distinct radiolucency beneath the apex of the second mandibular molar discovered through panoramic radiography, and confirmed via cone-beam computed tomography. In addition, the computed tomography disclosed a previously unreported and unusually large endodontic lesion that extended toward the mandibular canal; highlighting a necessity for the continued exploration of a unique endodontic presentation. A nonsurgical endodontic retreatment led to a remarkable reduction in the radiolucent lesions within one year; emphasizing the significance of comprehensive diagnostic approaches and individualized treatments.

Endodontic treatment in dens invaginatus anomaly is associated with challenges in all stages. This case report outlines the therapy provided for tooth #10 with occasional pain. In examinations, tenderness to percussion and touch and non-response to sensibility tests were observed, and pulp necrosis and symptomatic periapical periodontitis were diagnosed. Radiographic evaluation showed a structural anomaly related to the dens invaginatus and the associated periapical lesion. Cone-beam computed tomography confirmed the presence of DI type II. Endodontic treatment combined with photodynamic therapy and active irrigation using a dental operating microscope was successful and radiographic examinations showed periapical healing along with bone formation in 6-month and 1-year follow-ups.

Pulp Canal Obliteration Following Traumatic Dental Injury in an Upper Lateral Incisor: A Case Report with 3-year Follow-up

Marina da Cunha Isaltino, Wesley Viana de Sousa , Luiza de Almeida Souto Montenegro , Christianne Tavares Velozo Telles, Marcely Cristiny Figueredo Cassimiro da Silva , Diana Santana de Albuquerque

Iranian Endodontic Journal, Vol. 19 No. 2 (2024), 20 March 2024, Page 134-138
https://doi.org/10.22037/iej.v19i2.43307

Endodontic management of teeth afflicted with pulp canal obliteration faces a challenge due to the heightened risk of complications including excessive wear, perforation, and suboptimal chemomechanical preparation. This report aims to elucidate the clinical endodontic strategy employed in addressing pulp canal obliteration after a history of dental trauma and an associated periradicular lesion in an upper lateral incisor. A patient visited the dental emergency department with symptoms of apical swelling, acute persistent pain, and discoloration of tooth 22. Following comprehensive clinical evaluation and cone-beam computed tomography, the diagnosis of pulp canal obliteration involving the cervical and middle thirds of the tooth, alongside an acute periradicular abscess was established. Root canal was accessed using tomographic image planning, augmented by loupe magnification and ultrasonic instrumentation. Precise identification of the access cavity was radiographically confirmed, preceded by thorough irrigation with 2.5% sodium hypochlorite and subsequent cervical and middle third preparation. Verification of the working length by an electronic apex locator ensured precise apical preparation, followed by passive ultrasonic irrigation to optimize disinfection and to enhance penetrability of intracanal calcium hydroxide medication, administered for 15 days to eliminate microbial invasion. Upon resolution of symptoms, root canal obturation employing thermo-mechanical compaction and coronal sealing with composite resin was accomplished. Radiographic assessment after a one-year interval presented evidence of lesion regression and bone repair. Subsequent cone-beam computed tomography imaging at the three-year follow-up confirmed complete healing of the periradicular tissues, attesting to the efficacy of the endodontic intervention.