Cone-beam computed tomography analysis of primary root canals transportation and dentin loss after instrumentation with two-pediatric rotary files

BACKGROUND: This in vitro study aims to compare rotary files (Fanta and Zuanba) with manual K files according to the amount of dentin removed and canal transportation in primary mandibular second molars by CBCT images. METHODS: This experimental study was conducted on 60 extracted human second primary molars. That were divided into three groups according to root canal preparation group "I" instrumented with manual K-files, group "II" instrumented with rotary Fanta files, and group "III" instrumented with rotary Zuanba files. After root canal preparation, teeth were scanned before and after mechanical preparation with CBCT scanner. Then the amount of dentin removed was determined at three levels, including the coronal, middle and apical levels. Data were statically analysed using the Kruskal-Wallis test. RESULT: No statistically significant difference in the amount of dentin removed were noted between the manual and the rotary groups at the coronal and apical RC levels (P = 0.420) and (P = 0.819) respectively but significant difference was noted at the middle third (P = 0.043). Regarding RC transportation, no significant difference was noted among the three groups with the exception of the apical RC level (P = 0.043). CONCLUSION: Although no significant differences were noted between rotary and manual files, the rotary files showed better performance.