Assessment of irrigant flow and apical pressure in simulated canals of single-rooted teeth with different root canal tapers and apical preparation sizes: An ex vivo study

BACKGROUND: Irrigation dynamics vary in optimally shaped canals. Various factors combine to create a stress-induced environment leading to a dynamic irrigant flow. AIM: The aim of the study is to evaluate the irrigant flow and apical pressure using 30G open-ended needle in virtually created root canal model of single-rooted teeth. MATERIALS AND METHODS: Sixty extracted single-rooted premolars were selected and prepared using a single rotary instrument Hyflex CM and grouped as – Group I: 30 size 0.6% taper (n = 15), Group II: 30 size 0.4% taper (n = 15), Group III: 25 size 0.6% taper (n = 15), and Group IV: 25 size 0.4% taper (n = 15). Postinstrumentation imaging was carried out using cone-beam computed tomography, and computer-aided design models were obtained. Subgrouping was done based on the nozzle position, and computational fluid dynamic analysis was carried out for the respective parameters assessed. RESULTS: Statistical significance was elicited in all the groups at different nozzle positions analyzed (P < 0.05). A post hoc test revealed significance in the mean flow rate and flow velocity in Group I at low nozzle position (P < 0.05) as compared to others. CONCLUSIONS: 30 size 0.6% tapered preparations proved efficient irrigant flow and least apical pressures at all nozzle positions.