Background: In the endodontic therapy, the success of treatment depends solely on the endodontic triad, “diagnosis + anatomy +debridement =success”. Successful treatment depends on the debridement of the canal system with proper cleaning and shaping of canals being of utmost importance. So, we planned this study to evaluate the periapical healing and the incidence of procedural errors of molar teeth treated endodontically using a rotary technique as compared with manual preparation with stainless steel hand files. Materials and Methods: From the computerized hospital database, there were 973 primary (ie, first-time treatment, all retreatments excluded) nonsurgical root canal treatments completed for both maxillary and mandibular first and second permanent molars. Of these, 126 cases were randomly selected and constituted the group for which root canal instrumentation was performed by hand with a filing technique using stainless steel instruments (group 1). There were 973 primary endodontic treatments completed for the maxillary and mandibular first and second molars. A random Selection of 138 records were retrieved and checked to confirm that Root canal preparation had indeed been performed with the hybrid rotary technique using NiTi (continuous reaming by hand or engine Driven) instruments (group 2). All treatment records were examined in detail. Results: A total of 264 molars in 227 patients were examined; all of them had received treatment from a dental undergraduate or postgraduate student. Of all 225 teeth analyzed, totally, n=67 were deemed to be a failure to heal, whereas n = 197 showed complete resolution or definitive sign of healing. The group 2 was associated with a significantly higher rate of favorable/complete healing ( p < 0.05, chi-square test) and lesser amount of procedural errors (p < 0.05, Mann-Whitney test) than the group 1. Conclusion: Within the limitation of this study, we would conclude that NiTi instrument should be the choice for preparing root canals in primaryendodontic treatment, especially for inexperienced operator and forteeth with preoperative radiolucent lesions.
Keywords: Apical periodontitis, complications, failure, ledging, nickel-titanium instruments, periapical healing, procedural errors.