Iranian Endodontic Journal最新文献

Introduction: Knowledge of the internal anatomy of mandibular third molars is essential for successful endodontic treatment, yet their complex morphology often complicates management. This study evaluated the root canal morphology of mandibular third molars using cone-beam computed tomography (CBCT) according to Vertucci's classification.

Materials and methods: A total of 653 CBCT scans were screened, and 274 mandibular third molars meeting the inclusion criteria were analyzed. Root canal configurations were classified according to Vertucci, with atypical cases recorded as "type 0" for statistical purposes. Data were analyzed with Fisher's exact test (α=0.05).

Results: Vertucci type I was the most prevalent configuration (62.8%), followed by type V (17.4%). Sex and dental arch side significantly influenced the distribution of configurations (P=0.044 and P=0.013, respectively), while age did not (P=0.569). Distal and distolingual roots were predominantly type I, whereas mesial roots showed greater variability, particularly between sexes.

Conclusion: Mandibular third molars exhibit considerable anatomical variation, with types I and V being most frequent. Patient sex and arch side significantly affect root canal morphology, underscoring the importance of detailed preoperative assessment with CBCT for accurate endodontic planning.

Introduction: This in vitro study assessed the effects of bonding application time (immediate vs. 24-hour delay) and strategy [self-etch (SE) vs. etch-and-rinse (ER)] on cytotoxicity of three calcium silicate-based cements [calcium-enriched mixture (CEM) cement, ProRoot mineral trioxide aggregate (MTA) and Biodentine] at 1mm and 2mm thicknesses.

Materials and methods: Specimens (n=20 per group) were fabricated using CEM, MTA, and Biodentine. Scotchbond Universal was applied immediately or after 24 hours via SE or ER strategies. Cytotoxicity of cement extracts (100%, 50%, and 25% concentrations) on human gingival fibroblasts was evaluated using methyl thiazolyl tetrazolium (MTT) assay. Data were analyzed with four-way ANOVA and Tukey's test (P≤0.05).

Results: The biomaterials showed comparable cytotoxicity (P>0.05), with toxicity decreasing progressively at lower concentrations (25% <50%<100%). At 100% concentration, ER bonding significantly improved cell viability for CEM (P<0.05), while immediate bonding of 1-mm specimens increased cytotoxicity (P<0.05). Immediate SE bonding of 1-mm MTA and Biodentine specimens also resulted in higher cytotoxicity (P<0.05). At 50% concentration, SE strategy and 1-mm thickness increased cytotoxicity, with bonding time effects significant only in ER mode. No significant differences were observed at 25% concentration (P>0.05).

Conclusion: Delayed bonding (24 hours), ER strategy, and ≥2-mm thickness minimize cytotoxicity of calcium silicate-based cements. Clinically, immediate permanent restoration after vital pulp therapy is viable when considering these parameters, eliminating the need for interim protective layers (e.g., glass ionomer bases).

Introduction: This study aimed to assess the thermal behavior of five different commercial gutta-percha brands using optical thermography. We focused on temperature differences and heat transfer characteristics at different apical distances.

Materials and methods: Gutta-percha cones from the following brands were tested: Autofit Greater Taper, Protaper Gold F2, TruNatomy Prime, ZARC Gutta-percha points # 25/0.06, and Reciproc Blue R25. A specific heating system was used to subject the cones to thermal imaging. Measurements were taken at 1-, 2-, 3-, and 4-mm apical distances for 5 mm and 10 mm cone lengths. Statistical analyses included Student's t-tests and Analysis of Variance with the significance level set at 0.05.

Results: Upon intragroup comparison, we found subtle distinctions in thermal behavior when examining gutta-percha cone lengths (5 mm versus 10 mm). TruNatomy exhibited statistically significant variations (P<0.05) at 2- and 3-mm distances. Conversely, ZARC and Reciproc Blue R25 displayed notable differences (P<0.05) at 2-, 3-, and 4-mm distances. In contrast, Autofit Greater Taper and Protaper Gold F2 consistently diverged across all distances (P<0.05). In intergroup comparisons of 5 mm length, significant variances (P<0.05) emerged among brands at 1- and 2-mm distances. At 10 mm length, TruNatomy differed significantly (P<0.05) from other brands across all distances. The heat tip maintained an average maximum temperature of 154.54^°C.

Conclusion: Thermal behavior of gutta-percha brands varied significantly, with implications for endodontic treatments. While differences were observed in heat transfer and maximum temperatures, all brands remained within safe temperature ranges for clinical use. Understanding these variations can aid clinicians in selecting appropriate gutta-percha for specific clinical scenarios, ultimately optimizing root canal obturation quality.

Dens invagination (DI) is a developmental dental anomaly characterized by the infolding of the enamel organ into the dental papilla. Type IIIb DI, involving deep invagination that extends apically along the root, poses significant challenges in endodontic treatment due to its complex anatomy. We describe a case of type IIIb DI in a 13-year-old female referred with the chief complaint of spontaneous pain on the left maxillary lateral incisor. Clinical examinations showed tenderness to percussion and palpation as well as a positive response to cold test with lingering pain. Cone-beam computed tomography (CBCT) confirmed the presence of type IIIb DI associated with a periapical lesion. The final diagnosis was irreversible pulpitis with apical periodontitis for main canal (distal) and pulpless and infected root canal system with secondary acute apical periodontitis according to Abbott classification for the other canal. Two separate access cavities were prepared with the guidance of CBCT. Root canal therapy was performed on both root canals, using photodynamic therapy (PDT) and ultrasonic-activated sodium hypochlorite for enhanced disinfection. Calcium-enriched mixture cement was used to obturate the apical third, followed by thermoplastic gutta-percha in the middle and coronal thirds. The patient was asymptomatic at 6- and 12-month follow-ups, with radiographic evidence of complete healing. This case highlights the effectiveness of conservative endodontic treatment using PTD in managing complex DI cases, with a focus on maintaining tooth structure and achieving long-term success.

The management of extensive periapical lesions poses a significant challenge in endodontic therapy due to their potential cystic nature, anatomical proximity to critical structures, risk of cortical perforation, and complex infection dynamics. This report presents a successful case of a large through-and-through periapical lesion managed conservatively via decompression. Initial periapical radiographs revealed poor-quality root canal therapy and a large radiolucent lesion associated with a maxillary lateral incisor. Cone-beam computed tomography (CBCT) imaging confirmed a through-and-through lesion approximately 12×9.5×10.5 mm in size. Based on the clinical and radiographic features, pulpal diagnosis was previous endodontic treatment with an infected root canal system and the periapical diagnosis was a radicular cyst; however, a definitive diagnosis would have required a serial sectioning biopsy, which was not feasible under the present circumstances. Initial non-surgical retreatment as the first treatment choice, with multiple intracanal medicament replacements, proved ineffective due to persistent discharge of the canal. Furthermore, surgical intervention was deemed high-risk due to the lesion's proximity to the incisive foramen, palatal mucosa, sinus floor, and nasal cavity. Decompression, a minimally invasive technique with low morbidity, was selected. Following drainage, a drain was inserted via the thinnest cortical plate, and daily irrigation was initiated. The lesion was monitored every two weeks, with progressive reduction in size documented radiographically. After 5 months, the root canal was obturated and the tooth was restored by composite resin due to the cessation of drainage. The drain was removed at 6 months, and by the 9-month follow-up, significant bone regeneration was evident radiographically. The tooth was asymptomatic, exhibited no mobility or sensitivity to percussion or palpation, and periodontal probing revealed no pathologic pockets.

Treating coronal dens invaginatus (CDI) with pulp infection typically involves the removal of the invaginatus, which increases the risk of fracture and perforation, compromising tooth structure. Minimally invasive endodontic management of coronal dens invaginatus is highly recommended. This case report presents the management of a 19-year-old female patient with a permanent maxillary lateral incisor exhibiting two distinct dens invaginatus anomalies. Cone-beam computed tomography (CBCT) was used to assist in the diagnosis of tooth morphology and canal location. CBCT confirmed that the buccally positioned orifice was classified as Oehlers Type II, while the one with a palatally positioned orifice corresponded to Oehlers Type l. The pulp and periapical diagnosis of this tooth was pulpless and an infected root canal system with chronic apical periodontitis according to Abbott classification. The pulp chamber was carefully accessed with minimal intervention, and the root canals were explored under magnification. All root canals were prepared using EDMax rotary files, followed by irrigation with sodium hypochlorite (NaOCl). Calcium hydroxide medication was also applied. Root canal obturation was performed using the warm vertical compaction, employing AH-Plus sealer in combination with thermosplasticized gutta-percha. After 6 and 12 months, the patient showed healing of the periapical region, with the absence of symptoms and normal dental function. Favorable radiographic and clinical findings were observed during both follow-up sessions. At the 18-month follow-up, the lesion was completely healed.

Introduction: The dental pulp is a specialized connective tissue responsible for maintaining tooth vitality through a complex interplay of cellular, vascular, and immunological components. Despite the clinical use of conventional capping materials, their limited regenerative potential often results in pulp devitalization and compromised structural integrity. Recent advances in tissue engineering, particularly the application of three-dimensional scaffolds, have demonstrated promising outcomes in promoting dentin-pulp complex regeneration and biomimetic tissue repair. This systematic review and meta-analysis evaluated the efficacy of three-dimensional matrices, with or without bioactive materials, as direct pulp capping agents in animal models. Outcomes included cellularity, dentin thickness, dentin bridge formation, dystrophic calcification, inflammation control, and pulp organization compared to commercial materials.

Materials and methods: A comprehensive search was conducted in indexed databases and gray literature. A random-effects meta-analysis used standardized mean differences and the inverse variance method. Heterogeneity (I²), publication bias (Egger's and Begg's tests), and risk of bias (SYRCLE's RoB tool) were assessed. Statistical analyses were conducted using RevMan (P<0.05).

Results: Seventeen studies met the inclusion criteria, with 13 included in the meta-analysis. The risk of bias was predominantly low, yet the certainty of evidence was very low. Scaffolds significantly enhanced cellularity (P=0.02; I²=91%), dentin thickness (P<0.00001; I²=87%), and inflammation control (P=0.03; I²=20%) compared to controls. No significant differences were observed for dentin bridge formation (P=0.30; I²=63%), dystrophic calcification (P=0.14; I²=32%), or pulp organization (P=0.10; I²=0%).

Conclusion: Three-dimensional scaffolds demonstrated potential in promoting cellular activity, dentin formation, and inflammation control. However, their impact on dentin bridge formation, pulp organization, and dystrophic calcification remains inconclusive. Further high-quality studies are required to validate their clinical applicability.

An acute apical abscess (AAA) is a rapid-onset inflammatory condition characterized by spontaneous pain, pus formation, and swelling, often resulting from pulp necrosis. Complications may include systemic manifestations and severe outcomes, such as tooth extrusion. This case report describes a rare instance of AAA causing rapid extrusion of a maxillary central incisor in a 17-year-old female. The patient presented with spontaneous pain and mobility of the extruded tooth, accompanied by localized swelling. Clinical and radiographic evaluations revealed pulp necrosis, an AAA, and apical bone rarefaction. Emergency treatment was initiated, including intracanal medication with calcium hydroxide and temporary splinting of the tooth. Subsequent treatment involved obturation with gutta-percha and sealer, followed by permanent restoration. Radiographic and clinical recalls up to 5 years demonstrated complete periapical healing, normal tooth mobility, and no recurrence of symptoms. Effective management, including timely root canal therapy and splinting, led to successful long-term outcomes. This case underscores the importance of prompt diagnosis and immediate, tailored treatment to manage AAA and prevent severe complications.

Introduction: The middle mesial canal (MMC) of mandibular molars is of particular interest in endodontics due to its complexity. This study investigated the association between MMC presence in first and second mandibular molars and the radiolucency in the furcation area using cone-beam computed tomography (CBCT) scans.

Materials and methods: CBCT scans of 400 patients referred to the largest radiology center in Kerman City from January 1, 2022, to January 1, 2023, were examined. All CBCT scans were assessed for radiolucency in the furcation area and the presence of MMC. Variables, including age, gender, tooth number, and MMC presence were recorded. Chi-squared tests and logistic regression analyses were employed to compare MMC frequency and its impact on furcation radiolucency.

Results: Of 201 examined teeth, 37 (18.4%) had MMC, and 23 (11.4%) exhibited furcation radiolucency. However, teeth with a mesial canal showed a higher prevalence of furcation lesions compared to those without (38% vs. 5.2%) (P<0.001). A significant association was observed between a mesial canal and furcation radiolucency, with odds of furcation radiolucency at 12.7 after controlling for age and gender (P<0.001).

Conclusion: A strong association exists between MMC presence in first and second mandibular molars and furcation radiolucency, unaffected by age and gender.

Introduction: This study compared apical transportation and centering ability of TruNatomy, EDMax, and Reciproc Blue in curved mesiobuccal canals of mandibular molars.

Materials and methods: This ex vivo study was conducted on curved (20-40 degrees) mesiobuccal canals of 60 mandibular molars. The teeth were randomly assigned to 4 groups (n=15) for instrumentation of the mesiobuccal canals with (I) TruNatomy, (II) EDMax, (III) Reciproc Blue, and (IV) Reciproc Blue+R-Pilot. Cone-beam computed tomography (CBCT) scans were obtained before and after instrumentation. Changes in canal wall thickness in mesiodistal (MD) and buccolingual (BL) directions were assessed at 1, 2, 3, and 4 mm from the apex using OnDemand software. Data were analyzed by the Kruskal-Wallis, Bonferroni, Friedman, and Fisher's exact tests (alpha=0.05).

Results: TruNatomy showed significantly lower transportation than Reciproc Blue and EDMax in the apical, middle, and coronal thirds (P<0.05). Reciproc Blue and EDMax had no significant difference in transportation (P>0.05). Using the R-Pilot glider had no significant effect on transportation (P>0.05). Canal transportation was not significantly different within each group at four distances from the apex (P>0.05). TruNatomy showed significantly higher centering ability than Reciproc Blue+R-Pilot in the BL dimension at 3 mm from the apex (P<0.05).

Conclusion: TruNatomy showed significantly lower canal transportation than Reciproc Blue and EDMax at all distances from the apex. The files had no significant difference in centering ability except at 3 mm in BL dimension, where TruNatomy had significantly higher centering ability than Reciproc Blue+R-Pilot.