Purpose: To evaluate the adhesion of AH26 and Epiphany sealers to gutta-percha/Resilon surfaces and dentine in the presence or absence of the smear layer.
Methods: Dentine, gutta-percha, and Resilon surfaces were filled with different combinations of AH26 and RealSeal sealers in eight groups: Group 1- Smear (-) dentine, filled with dentin bonding agent and AH26 sealer; Group 2- Smear (+) dentine, AH26; Group 3- Smear (-) dentine, AH26; Group 4- Smear (-) dentine, RealSeal sealer. In the remaning groups, gutta-percha and Resilon pellets were used as experimental surfaces to test the sealer adhesion. The samples were attached to a universal testing machine and pulled at 1 mm/s to determine the tensile bond strengths.
Results: Statistical analyses revealed that the smear free dentine filled with AH26 had a significantly higher bond strength than those of the other groups (p< 0.05). The presence of the smear layer and dentine bonding agent significantly reduced the adhesion of AH26 to dentine (p< 0.05). The bonding of AH26 to Resilon and gutta-percha was significantly better than those of the RealSeal sealer (p< 0.05).
Conclusion: The tensile bond strength of AH26 sealer to gutta-percha/Resilon and dentine was superior to that of RealSeal sealer.

Purpose: The aim is to determine the effect of different lengths of post-space preparation on the incidence of root crack formation using micro-computed tomography (micro-CT).
Methods: Forty-two single and straight-rooted human mandibular premolar teeth were used. Teeth were randomly divided into two groups (n = 21). All teeth were scanned using micro-CT before and after the canal shaping, followed by filling with gutta-percha and a resin-based root canal sealer. Different lengths of post-space (1/2 [Group 1] and 2/3 [Group 2] of the canal length) were prepared for the teeth in Group 1 and Group 2. Teeth were again scanned with micro-CT.
Results: After the post-space preparation, no new microcrack formation was observed. As a result of the propagation of microcracks detected in the first scan, completed fractures were detected in 3 teeth in Group 1 and 2 teeth in Group 2.
Conclusion: It can be concluded that the different lengths of post-space preparation did not affect the incidence of microcrack formation in root dentin.

Purpose: The aim of this study was to evaluate the matching properties of the gutta-percha (GP) cones and different file systems with variable tapers.
Methods: Fifteen files and GP cones TruNatomy Prime (TRN-P), WaveOne Gold Primary (WOG-P), and Reciproc Blue (Rec-B R25) systems were examined under a scanning electron microscope. Diameter measurements of files and GP cones were made from D1 to D16 using AutoCAD software. Data were analyzed with independent samples t-tests. Statistical significance was determined as p< 0.05.
Results: The diameters of the file and GP cones were within the acceptable tolerance range. The file diameter was larger than the GP diameter at all points of incompatibility in the TRN-P system (p< 0.05). In the WOG-P group, the file diameter was wider up to the D10 level, while the GP cone diameter was wider at the D11 point and beyond p<0.05. In the Rec-B group, the file diameter was wider up to the D6 level, while the GP cone diameter was wider at the D7 point and beyond p<0.05.
Conclusion: Three file systems are largely incompatible with the GP cones. In the TRN file system, unlike the other two groups, the GP cone had a narrower diameter than the file at each point.

Purpose: In this in vitro study, the smear layer removal efficiency of 17% ethylenediaminetetraacetic acid (EDTA), 10% glycolic acid (GA), and 18% etidronic acid, 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) solutions was evaluated.
Methods: A total of 80 human mandibular premolar teeth were used in the study. The teeth were prepared using the Reciproc R25 rotary instrument system. A total of 10 mL of 2.5% NaOCl irrigation solution was used: 5 mL during the procedure and 5 mL after it. The teeth were divided into four groups (n = 20): group 1, 17% EDTA + passive ultrasonic activation (PUI); group 2, 10% GA+PUI; group 3, 18% HEBP + PUI; and group 4 (control group), distilled water + PUI. Based on the central parts of the coronal, middle, and apical thirds images were taken under a low vacuum scanning electron microscopy at 2000× magnification. The presence of smear layer in the coronal, middle, and apical thirds was evaluated using a five-score evaluation system. Data were analyzed with Kruskal–Wallis and Dunn tests.
Results: No statistically significant difference was found among the groups 1, 2, and 3 in all regions (p>0.05).
Conclusion: EDTA, GA, and HEBP irrigation did not affect the smear layer removal by PUI.

Purpose: The present study aimed to compare the apical sealing ability of three different obturation techniques, namely cold lateral condensation, carrier-based obturation (GuttaCore), and single cone (GuttaFlow Bioseal) using a dye penetration method.
Methods: Freshly extracted mandibular premolars were collected. After biomechanical preparation, samples were divided into three groups (n = 15) and were obturated. Each root was coated with nail polish except the apical 3 mm. Samples were immersed in 2% methylene blue for 72 h at 37°C. All the roots were sectioned buccolingually. Samples were then examined under a stereomicroscope at 0.8×. The linear extent of dye penetration was measured in mm from the apical end of the preparation.
Results: Cold lateral condensation technique showed the highest amount of apical microleakage, fol- lowed by GuttaCore and GuttaFlow Bioseal. A statistically significant difference was found when GuttaFlow Bioseal was compared with cold lateral condensation and GuttaCore. The results were not statisti- cally significant when cold lateral condensation and GuttaCore were compared.
Conclusion: GuttaFlow Bioseal, in combination with the single cone technique, shows better apical sealing ability when compared to carrier-based obturation (GuttaCore) and cold lateral condensation technique.

We present an unusual case of contact dermatitis of the face following the use of formocresol. A 23-year-old
man presented to our hospital, 3 days after his dental appointment, with moderate pain and a burning sensation related to a patch of darkly discolored skin. Questioning his dentist revealed that he used formocresol as an intracanal medicament. The root canals had been extirpated and formocresol had been placed into tooth #26 as a medicament. The dentist admitted that he accidentally touched the patient’s face with his formocresol-contaminated hands. Formocresol was removed from the canals and calcium hydroxide was placed. Then, a dermatology consultation was requested and it was diagnosed as irritant contact dermatitis. Complete healing was observed with appropriate drug therapy. The present case urges us to pay attention to preventive isolation methods and not to prefer formocresol, which can cause serious clinical manifestations, as an intracanal medicament.

The radicular cysts are the most common odontogenic cysts affecting jaws. Paresthesia is rarely seen and associated with paresthesia is usually associated with the pressure of enlarged endodontic lesions on the mandibular nerve. This case report presents a radicular cyst in a 22-year-old healthy female patient and the treatment based on a review of the literature. The radiography showed a large radiolucency with a radiopaque margin involving the apices of the mandibular right second and third molars. The patient’s complaint of paresthesia disappeared after the endodontic treatment. The patient’s 4-year follow-up showed satisfactory healing with no clinical symptoms, and recovery of the periapical bone bone was observed.