Evaluation of coronal leakage and pathway of dye leakage after obturation with various materials for open apical foramina.

The aim of this study was to investigate coronal leakage after obturation with mineral trioxide aggregate (MTA), resin-based sealer, and silicon-based sealer for open apical foramina and to evaluate pathway of leakage. Twenty-eight maxillary premolars were used, and instrumented to ISO size #80. Teeth were randomly divided into four groups as follows: Group A filled with MTA, Group B with gutta-percha and resin-based sealer, Group C with polymer-based material and resin-based sealer, and Group D with gutta-percha and silicon-based sealer. All samples were evaluated for coronal leakage with methylene blue solution and spectrophotometry. After leakage testing, samples were cut, and sections were observed. Dye leakage of Group A was significantly lowest among all groups at 15 days and 30 days. Defects which induced coronal leakage in resin-based sealer were observed at 7 mm from the apex. Coronal leakage after obturation with MTA for open apical foramina was significantly lower than resin-based sealer and silicon-based sealer.

Detection of root surface fractures with swept-source optical coherence tomography (SS-OCT).

OBJECTIVE: The purpose of this study was to compare optical coherence tomography (OCT) with the existing technologies, to assess its accuracy and utility in detecting vertical root fractures of extracted human teeth. BACKGROUND DATA: The detection of root fractures in teeth that have undergone root canal treatment is challenging because of the great difficulty in differentiating these fractures from morphologic or radiographic anomalies. OCT methods are based on depth-resolved optical reflectivity and have been developed to reduce the invasiveness and radiation exposure inherent to other techniques. METHODS: Twelve extracted human mandibular teeth (totaling 25 roots) that were free of caries, calculus, and root treatment were used, and assessed by microfocus computed tomography, the current gold standard for fracture detection. The ability of appropriately trained observers to detect root fractures using visual, microscopic, and swept-source OCT (SS-OCT) techniques were compared. micro-CT and SS-OCT produce three-dimensional images of the tooth from which to diagnose fractures, but CT scanning involves radiation exposure that is not required in SS-OCT. RESULTS: Seventeen of the 25 roots were found to have fractures by microfocus CT. These findings were replicated by SS-OCT, which revealed fractures exhibiting identical origin, size, and angulation within the root. We found that SS-OCT gave results compatible to the gold standard technique, and that SS-OCT and microscopy were more effective for identifying root fractures than was visual observation alone. CONCLUSIONS: SS-OCT may represent a novel, noninvasive, noncontact and nonexposure alternative to the conventional methods used for assessing root fractures in teeth.

Clinical management of dens invaginatus in a maxillary lateral incisor with the aid of cone-beam computed tomography--a case report.

This report describes non-surgical endodontic treatment of Oehlers' type III dens invaginatus in a maxillary lateral incisor with the aid of postobturation cone-beam computed tomography (CBCT). The endodontic treatment was initiated with the aid of a surgical operating microscope, and two canals, one of which represented the invagination, were instrumented, irrigated under passive ultrasonic activation and obturated with the lateral condensation technique. As postobturation periapical radiographs suggested the presence of untereated and/or unfilled areas in the root canal and invagination, CBCT was taken to assess the possibility of further treatment. The CBCT scans demonstrated inaccessible and unfilled canal and invagination areas because of complex internal morphology characterized by (i) C- or ring-shaped cross-sectional canal configuration with constrictions at different points in different root levels and (ii) a prominent intraradicular cavity that was communicated with the enamel-lined invagination and opened into the apical periodontium. Thus, it was judged that further endodontic treatment was not feasible. A 14-month follow-up revealed a satisfactory clinical and radiographic outcome, suggesting that the chemomechanical debridement may have sufficed to induce periapical healing. CBCT greatly helped the decision of avoiding further intervention that could have been difficult to negotiate.