Comparison between the accuracy of NovApex apex locator and radiographs in determining radiographic apex

Determination of the canal working length with radiographs has many drawbacks. Electronic apex locators have been developed to overcome some of these problems. Recently, a newly designed apex locator called NovApex has been introduced. All the studies conducted to determine the accuracy of NovApex have been carried out in-vitro on extracted teeth. The aim of this in vivo study was to evaluate the accuracy of NovApex compared with traditional radiographic method. Twenty-five patients whose lower molars that were candidates for extraction were selected. The teeth were accessed, and the radiographic working length was determined by measuring the length of the initial file 0.5mm short of the radiographic apex. Then, NovApex apex locator was used to measure the electronic working length. Subsequently, the tooth was extracted, and the actual working length was measured by introducing a size #15 K-file into each canal until the file tip was visible at the apex, then 1.5mm was subtracted to attain the working length. Cohen's Kappa was computed for each of the methods versus actual working length as a measure of reliability. The accuracies were compared using Chi-square test. The accuracy of NovApex apex locator and radiographic method in detecting the apical end point within +/- 0.5mm was 74.7% and 68%, respectively; this was not significantly different [P<0.001]. The NovApex apex locator is useful in detecting the apical end point with the accuracy similar to radiographic method. However, neither technique is fully reliable in detecting the apical end point of the canal

Endodontic management of a fused mandibular second molar and paramolar: a case report

Tooth fusion is a developmental anomaly characterized by the union between the dentin and/or enamel of at least two separately developing teeth. The fusion of posterior teeth is an uncommon occurrence. In this article, we report a rare case of unilateral fusion of a mandibular second molar with a paramolar. Carious exposure mandated endodontic treatment. The unusual morphology and complex root canal system makes diagnosis and treatment difficult. In this case, successful endodontic management was carried out with precise application of hand and rotary techniques

Cytotoxicity of cold ceramic compared with MTA and IRM

Biocompatibility is a desirable feature for root-end filling materials. In this study we aimed to compare a new material called cold ceramic [CC] with intermediate restorative material [IRM] and mineral trioxide aggregate [MTA] using Methyl-tetrazolium bromide [MTT] assay. The materials were tested in fresh and set states: [n=108]. The cytotoxicity was compared using L929 fibroblasts as an indicator; tested materials were eluted with culture medium according to ISO: 109935 standard. Distilled water and culture medium served as positive and negative controls, respectively [n=36]. The results were evaluated at 1, 24 hours and 7 days. Data were statistically analyzed by one-way ANOVA for each time interval and material status and t-tests. The cytotoxicity of the tested materials were statistically different at the various time intervals [P<0.001]. IRM was the most cytotoxic root-end filling material [P<0.001], MTA demonstrated the least cytotoxicity followed by CC. Despite displaying the greatest cytotoxicity, IRM is approved by the American Food and Drug Administration [PDA]. Cold ceramic had significantly lower cytotoxicity compared to IRM, in all but one subgroup. Further investigations are required to assess the clinical applicability of this novel material