Iranian Endodontic Journal最新文献

Root canal mishaps such as perforations, separated instruments, and canal ledges remain significant challenges in endodontic retreatment. This case report describes the successful non-surgical management of a mandibular first molar presenting with a strip perforation in the mesiobuccal canal, a separated file in the mesiolingual canal, and a ledge in the distal canal. The tooth was generally asymptomatic with only mild sensitivity to percussion, without any pockets of endodontic origin. Radiographic examination revealed periapical and furcation radiolucencies. The tooth had a previous endodontic treatment with an infected root canal system and chronic apical periodontitis. Notably, the tooth was left undressed for approximately three months following the initial mishap, negatively influencing prognosis. Nonetheless, considering the patient's preference and the favorable periodontal and restorative conditions, non-surgical retreatment was initiated. Treatment included thorough chemomechanical preparation, bypassing the separated file and ledge, and sealing the perforation with calcium-enriched mixture cement. The tooth was subsequently restored with bonded composite resin. At 12-month follow-up, radiographic signs of healing were evident, and at 18 months, the tooth remained asymptomatic with no clinical or radiographic signs of apical or furcation pathology.

Dens invaginatus is a developmental malformation that is caused by the invagination of the enamel organ into the internal region of the dental papilla before tissue calcification. The aim of the present report is to discuss a clinical case of endodontic treatment of tooth #12, using bioceramic sealer. The extraoral examination revealed atypical anatomy, while vitality and percussion tests were negative, palpation test was positive. Edema was observed in the adjacent gingival mucosa. Based on clinical and tomographic findings, the diagnosis was pulp necrosis with chronic periapical abscess and Oehlers' type II dens invaginatus. In the first session, access surgery was performed with spherical drills with the aid of an operating microscope (OM) and an ultrasonic diamond tip. Four canals were located, and they were partially debrided and medicated. In the second session, odontometry and chemical-mechanical preparation with nickel-titanium instruments were performed. The irrigation solution was 2.5% sodium hypochlorite. The root canals were filled with calcium hydroxide paste and the chamber was temporarily sealed. During the third session, ultrasonic irrigation was applied for final washing and the root canals were filled with Bio-C sealer using the classic single-cone technique. At 6-month follow-up, the tooth was asymptomatic and the radiography revealed significant bone repair. It was concluded that tomography, operating microscope, ultrasonic irrigation, and materials with greater flow, such as bioceramic sealers, enhanced the clinical success of the clinical case.

Introduction: The present study aimed to evaluate the instrumentation time and transportation ability of three file sequences sharing the same physical properties (diameter, tip design, cross-sectional shape, and taper), each manufactured entirely of one single alloy type (Pink, Blue, or Gold).

Materials and methods: One hundred and eighty simulated curved resin canals were instrumented using the BlueShaper system, with full Z1-Z4 sequences, each made entirely of a single alloy type (Pink, Blue, or Gold). Images before and after instrumentation of each specimen were overlaid with Photoshop software to evaluate centering ability in the coronal, middle, and apical thirds. Data were analyzed using one-way analysis of variance (ANOVA) with post hoc multiple comparisons or the non-parametric Kruskal-Wallis test for intergroup analysis.

Results: No significant differences were found between the different alloys in the centering ability of the simulated canals in the coronal third (P>0.05). The Blue alloy of the BlueShaper system showed significantly less transport ability in the middle third than Pink and Gold alloys (P<0.05). A significantly lower centering ability (P<0.001) was observed in the apical third between the Blue and Pink alloys than the Gold alloy.

Conclusions: It was concluded that the Blue alloy performed better than the Pink and Gold alloys in the middle and apical thirds. The pink alloy performed better than the Gold alloy in the apical third.

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.