SEM Evaluation of Various Intracanal Irrigation Devices on Smear Layer Removal: A Comparative Study.

AIM: The present study aimed at assessing the effectiveness of different intracanal irrigation devices on the removal of the smear layer. MATERIALS AND METHODS: The recently extracted 80 lower premolars having single canal were chosen for this in vitro study. A round diamond bur was used to gain endodontic access and the root canal was entered with a #15 K-file until the tip was just seen at the apical foramen. Manual instrumentation of root canals of all teeth was done using the step-back method. The samples were later divided randomly into four groups. Later, each sample was exposed to final irrigation by using four different irrigation systems, group 1: conventional needle irrigation, group 2: irrigation with ultrasonic activation, group 3: irrigation with EndoVac system activation, group 4: irrigation with EndoActivator. The samples were next mounted and visualized under scanning electron microscope (SEM) for the absence or presence of the smear layer. RESULTS: Irrigation with EndoVac system activation showed the presence of least smear layer (2.40 ± 0.32), followed next by EndoActivator (3.24 ± 0.46) and ultrasonic activation (4.96 ± 0.54) and conventional needle irrigation (5.20 ± 0.10). No statistically significant difference was found in the apical and coronal thirds of the root canal in removal of the smear layer on an intragroup comparison. However, a statistically significant (p < 0.001) difference was seen between the groups at the apical and coronal thirds on an intergroup comparison. CONCLUSION: This study demonstrated the EndoVac system group to be efficient in removal of the smear layer when compared to the EndoActivator system, ultrasonic activation, and conventional needle irrigation group. CLINICAL SIGNIFICANCE: The definitive objective of endodontic therapy is to transform the affected teeth to a healthy and functional state. The irrigants can reach the working length when delivered by an effective irrigation delivery system. This type of delivery system should deliver adequate volume of irrigants all the way up to the working length and have sufficient flow and be efficient at debridement of complete canal system.

Electrochemical dissolution and retrieval of broken NiTi endodontic files from root canal using chloride based isotonic fluids as electrolytes - An in vitro study.

Objective: The electrochemical dissolution method of instrument retrieval emphasizes on the dissolution of the instrument rather than sacrificing dentine. Most of the studies conducted for electrochemical dissolution used fluoride-containing electrolytes and were performed inside a beaker. In this study, we used chloride-based fluids as electrolytes. Materials and Methods: Fifty extracted mandibular first premolars were divided into five groups based on the electrolytes used. Canals were enlarged to ProTaper Universal F2, and files were intentionally broken inside the canal. These specimens were subjected to electrochemical characterization by applying the potential of 9V for 20 min. Optical images were taken to assess the change in surface topography. The results were analyzed statistically by one-way analysis of variance (analysis of variance [ANOVA]). Results: The rate of dissolution based on the electrolyte used decreased in the following order, viz. Tyrode's solution>artificial saliva>normal saline>Ringer's lactate/physiological serum. Conclusion: Apart from fluoride, chloride-based electrolytes could be an efficient alternative.

Management of Tooth Fractures Using Fiber Post and Fragment Reattachment: Report of Two Cases.

Reattachment of the tooth fragment is an ultraconservative technique for managing coronal tooth fractures when the tooth fragment is available, and there is minimal violation of the biological width. The advances in adhesive dentistry have allowed dentists to use the patient's own fragment to restore the fractured tooth which provides fast and esthetically pleasing results. This article reports fragment reattachment technique and presents two clinical cases of complicated crown fracture.