A Comparative Evaluation Of The Apical Foraminal Deformation Caused By Three Rotary File Systems: An In Vitro Study

Background: Apical foramen enlargement is considered beneficial during endodontic treatment of necrotic teeth. However, this causes deformation and deviation of the apical foramen which may lead to faulty obturations, sealer extrusion, etc. Aim: To compare the apical foramen deformation caused by Protaper Gold, Profit S3, and Hyflex CM rotary file systems in mandibular molars. Materials and Methods: Thirty mesial root canals in fifteen extracted mandibular molars were included in the study. Access cavities were prepared, WL was established at the apical foramen. The canals were divided into 3 groups (n=10) : Group 1 - Protaper Gold(PTG); Group 2 - ProFit S3(PS3); Group 3 - Hyflex CM(HCM). Instrumentation was done up to file size #25/0.06. Pre and post instrumentation AF areas (A0, A1) were assessed using a stereomicroscope at 100X magnification. Foraminal deformation was calculated for each canal by subtracting A1-A0. Statistical analysis was done using ANOVA and posthoc Tukey tests. Results: Apical foraminal deformation was present in all samples. The mean area of apical foramen, postoperatively, was 0.01804mm for Protaper Gold, 0.01046mm for Profit S3 and 0.01476mm for Hyflex CM systems. Profit S3 system showed the least AF deformation compared to Protaper Gold and Hyflex CM systems. Conclusion: ProFit S3 system showed the least foraminal deformation compared to the Protaper Gold and Hyflex CM systems. The alloy, taper, and cross-section of the file may play an important role in the degree of deformation produced.