ABSTRACT
Objective This study aimed to evaluate the effect of three different commercially available intra-orifice barriers and bleaching agents on root canal-treated teeth. Materials and methods Forty-five freshly extracted single-rooted incisors, canine, and premolars were collected and stored in 10% formalin. Root canal procedures were performed on the extracted teeth and these were classified into three groups and three subgroups (n=5). Group 1: resin-modified glass ionomer cement (RMGIC); placed at the level of cemento-enamel junction (CEJ) and cured for 20 seconds. Group 2: BiodentinTM (Septodont Ltd., Saint Maur des Fausse´s, France); powder and liquid were mixed according to the manufacturer's instructions and placed at the level of CEJ, and waited for 15 minutes to set. Group 3: bulk-fill composite; placed at the level of CEJ. Group A was treated with 35% carbamide peroxide (Ultradent Opalescence 35% PF regular). Group B was bleached with 35% hydrogen peroxide (Pola Office). Group C, which was the control group, was treated with distilled water. The bleaching procedure was repeated once every seven days for a period of three weeks. After bleaching, every sample was sectioned 2 mm above the level of CEJ to remove the crown. Auniversal testing machine (UTM) was used for the evaluation of the fracture resistance of teeth. Data were analyzed for significance by using analysis of variance (ANOVA) and further pair-wise comparison was performed by pos-hoc analysis. The level of significance was set at p<0.05 Results There was a significant difference between the fracture resistance of the three materials when bleached using distilled water (p<0.05). The fracture resistance of Group 3 was significantly greater than that of Group 2 and Group 1 (p<0.05). The difference in the fracture resistance between Group 1 and Group 2 was nonsignificant (p>0.05). Conclusion Walking bleach performed via bleaching agents 35% carbamide peroxide and 35% hydrogen peroxide leads to a reduction in the fracture resistance of endodontically treated teeth; 35% hydrogen peroxide causes more fracture resistance reduction than carbamide peroxide of the same concentration. The presence of intra-orifice barriers leads to greater fracture resistance and reinforcement of endodontically treated teeth that undergo the walking bleach procedure. Bulk-fill composite can be used as an intra-orifice barrier with good fracture resistance.
ABSTRACT
Digitalization of operative procedures through three-dimensional (3D) navigation is a remarkable advancement in the field of dentistry which allows both precision and accuracy while treating patients. It is an emerging technology with a wide variety of applications in dentistry. In the field of endodontics, these computer-aided 3D systems are being used for accessing and localizing canals in calcified teeth, removal of fiberglass posts, and in peri-apical surgeries etc. Preservation of important anatomical structures becomes necessary while performing root-end resection or peri-apical surgeries. However, it is clinically difficult to achieve accurate root-end resection due to the limited field of view, inconvenient perspective, and interferential bleeding among other factors. 3D guided endodontics play vital role here. 3D guided endodontics can be achieved in two ways- Static and Dynamic navigation. Due to availability of limited literature, there is a need to review new evidence comparing the effectiveness of both techniques of 3D guided endodontic navigation systems. This review paper describes the comparative evaluation of the effectiveness of static as well as dynamic navigation in the field of endodontic microsurgery.
