Aim and objective: To evaluate and compare the depth of cure of two bulk-fill composites with a conventional composite. Materials and methods: A sample size of 36 was taken and divided into three groups based on the type of composite. Standardized cylindrical stainless steel molds were prepared with 8 mm diameter and 10 mm depth. Measurement of depth of cure by the scraping method was performed according to the ISO 4049 (2009). After placing the specimens, the mold was pressed with polyester strips covered by glass slides and curing was initiated using Bluephase 20i (Ivoclar Vivadent US) light-curing unit through the glass slide. Immediately after curing, the specimens were removed from the mold and the uncured part of the specimens was removed by scraping with a plastic spatula. The absolute length of the hardened composite specimen was measured using a digital vernier caliper. The measured length was divided by two and recorded as the ISO depth of cure. Results: The depth of cure of the composite specimens was found to be higher for Voco Xtra Fil bulk-fill composite than for Shofu Beautifil bulk-fill composite and Filtek Z350 XT conventional composite (3M/ESPE). Conclusion: Within the limitations of the study, it can be concluded that the placement of bulk-fill composites with 3-mm increments is mandatory for complete curing. Clinical significance: Depth of cure of bulk-fill composites determines the adaptation of restoration to the tooth structure, and this study aims to evaluate two newly introduced bulk-fill composites using scrape test.

Aim and objective: This research compares the abilities of the preparation of ProTaper Next (PTN; Dentsply-Maillefer) and XP-endo Shaper (XPS; FKG, Switzerland) files in mesial canals of lower molars with separate binary canals and one foramen with isthmus connection using µCT imaging. Materials and methods: The comparison showed 20 roots matched according to the similarities in preoperative canal volume, specimen length, and root curvature using preoperative scans, and then they were indiscriminately separated into two groups and prepared either with PTN or XPS instruments. After chemomechanical preparation, the roots were resubmitted to postoperative scans. Results: There was no variance in instrument systems for the volume of removed dentine, surface area as well as the amount of accumulated debris in the isthmus region (p >0.05). Change in canal surface area and amount of accumulated hard tissue debris (AHTD) was more in the PTN group for total root canal space (p <0.05). PTN instruments increased surface area in a shorter period. Conclusion: Both instrument systems with different design and metallurgic properties had reached the desired volume in different periods; however, neither technique was able to fully prepare the isthmus-containing mesial roots of lower molars.

Aim and objective: This study assessed the fracture resistance and failure mode frequencies in three post and core systems: CAD/CAM-fabricated glassfiber post and core, glassfiber post and core customized with composite resin, and cast metal post and core. Materials and methods: After endodontic obturation and the post space preparation, 30 extracted mandibular premolars were distributed into three groups (n = 10): Group GFP: glassfiber post and core customized with composite resin, Group CPC: cast metal, and Group CAD/CAM: CAD/CAM-fabricated glassfiber post and core. All the specimens were luted with RelyX U200 cement, submitted to thermomechanical cycling, and then submitted to a compression test, applied at a 45° angle relative to the long axis of the tooth, until fracture. The fracture resistance data were submitted to ANOVA complemented by the Tukey test and the failure mode data by Fisher's exact test with the Freeman–Halton extension (α = 5%). Results: There was no significant difference between the fracture resistance values found for groups CPC and CAD/CAM (p >0.05), and these values were significantly higher than those found for Group GFP (p < 0.05). In respect to failure mode frequencies, Group CAD/CAM had equal frequencies of adhesive and cohesive failures, Group GFP had exclusively cohesive failures in the composite core buildup, and Group CPC had 80% of cohesive failures in dentin vs 20% of adhesive failures (p < 0.001). Conclusion: The fracture resistance of CAD/CAM-fabricated glassfiber posts and cores was comparable to that of cast posts and cores, and they were not associated with irreparable root fractures. Therefore, CAD/CAM-fabricated glassfiber posts and cores can be considered an effective method for restoring endodontically treated teeth. Clinical significance: CAD/CAM system proved to be a viable alternative to cast posts and cores, since they were less associated with irreparable root fractures.

Background: The restoration of endodontically treated tooth (ETT) with substantial loss of the tooth structure is challenging as it carries a higher chance of biomechanical failure than vital tooth in restorative dentistry. Post combined with complete coverage restoration is a well-established technique to save such teeth from fracture, but it does not follow the minimal invasive principles of adhesive dentistry. Case description: This case report describes the management of endodontically treated mandibular premolar with lithium disilicate glass-ceramic endocrown (Emax). Conclusion: Endocrown is a feasible option for the restoration of extensively damaged posterior tooth after endodontic treatment. Since posterior teeth are vulnerable to tooth loss, endocrown, which is a single partial restoration, can be regarded as replacing a single crown with intraradicular retention.

Success in root canal treatment is achieved after thorough cleaning, shaping, and obturation of the root canal system. The main reason for the unsuccessful root canal treatment is the lack of knowledge of anatomic variations and the characteristics of the different teeth. A mandibular first molar with the third distal canal is very rare, and its occurrence has been reported to be around 0.6%. This article presents the endodontic management of the first mandibular molar with mid-distal canal, which is not quite common.