Root Canal Treatment With a Single Instrument: A Micro CT Evaluation

Objective. This study was conducted to evaluate the performance of a new NiTi instrument during root canal treatment. Background. Since the advent of NiTi rotary instruments root canal therapy has become a standard. All manufacturers have claimed that their 5 or 6 instruments are the best in performing root canal therapy. Methods. Teeth total, comprising of recently extracted mandibular molars (n=22) were obtained and stored in deionized water and thymol. No previous endodontic treatment had been performed on the specimens, and the presence of large or metallic restorations, cervical defects and root fractures would exclude the tooth from the study. All tooth handling and preparation was performed using appropriate barrier techniques to prevent potential cross-infection and all the experimental procedures were carried out by one experienced operator. Removal of adherent soft tissue and calculus was performed after soaking the teeth for 10 m in 5.25% sodium hypochlorite by hand scaling. The teeth had endodontic access cavity preparations prepared without coronal preflaring, under copious water spray. To ensure canal patency a number 10 K file was used to penetrate the canals to the terminus and an interproximal radiograph was taken with the file in situ to confirm the presence of either a Type II or III canal system and to exclude any root segments having unusual canal anatomy. The 4 file was placed at the level of the apical foramen and measured; the working length was determined to be 1 mm short of this length. All teeth were cleaned and shaped using one single instrument in one canal and another NiTi in the other canal. Results and Conclusions. Will be presented at Research Day.