Comparative evaluation of root dentin thickness following hand and rotary instrumentation of primary molar root canals using cone-beam computed tomography - an invitro study

BACKGROUND: Remaining Root Dentin Thickness (RRDT) after root canal instrumentation is an important parameter to be assessed with newer file systems. This study aimed to evaluate the root dentin thickness following instrumentation of primary molar root canals using manual or pediatric rotary file systems. METHODS: Fifty-one extracted human primary molars were prepared with access cavity preparation and working length determination. Preliminary Cone Beam Computed Tomography (CBCT) images were obtained with specimens mounted on vinyl polysiloxane templates. Root dentin thickness was measured at three predetermined levels. 51 mesiobuccal canals were randomly divided into 3 groups of 17 each. After instrumentation using the allocated file system i.e. Group 1 - Manual K files; Group 2 - Kedo SG Blue and Group 3 - Kedo S Square rotary files, CBCT images of the specimens were obtained. The remaining root dentin thickness was obtained using measurements of pre-and post-instrumentation CBCT. Data was analysed using paired t-test for intragroup comparisons. Intergroup comparison of RRDT was done using ANOVA. RESULTS: The Remaining Root Dentin Thickness (RRDT) after instrumentation did not differ significantly among the three study groups at the three predetermined levels (p > 0.05). CONCLUSION: Kedo S Square and Kedo SG Blue file systems showed comparable effectiveness to the manual K file system in the instrumentation of mesiobuccal canals of primary molars.