Effect of Cervical Preflaring on Initial Apical File Size Determination in Maxillary Central Incisors and First Molars

Abstract

Background: Cervical or coronal preflaring allows a more accurate assessment of the apical diameter of the root canal. This article investigates the influence of cervical preflaring-using different rotary instruments on the determination of initial apical width of the canal. Materials and Methods: 40 maxillary central incisors and maxillary first molars were assigned for this study. Actual canal length (working length [WL]) was determined with patency file. The teeth were divided into four Sub groups-Sub Group A had no preflaring. Sub Group B-preflaring with Gates Glidden. Sub Group C-preflaring with Quantec Flare series instruments. Sub Group D-preflaring with LA (line angle) Axxess burs. Each canal was instrumented starting with size 08 files and file sizes were increased until a binding sensation was felt at the WL. The apical region was then observed under a stereomicroscope, and the differences between a root canal and maximum file diameters were evaluated for each sample. Results: Significant differences were found among experimental groups regarding anatomical diameter at the WL and the first file to bind in the canal (P < 0.0001, 95% confidence interval). The major discrepancy was found when no preflaring was performed (0.172 mm for incisors and 0.162 mm for molars average). The LA Axxess burs produced the smallest differences between anatomical diameter and first file to bind (0.03 mm for incisors and 0.042 mm for molars average). Gates Glidden drills and flare instruments were ranked in an intermediary position, with no statistically significant differences between them. Conclusion: From the present study, it can be inferred that the canals preflared with LA Axxess burs presented the lowest discrepancy values between the file size and anatomical diameter, thus proving its role as an adjunct in root canal preparation procedures.

Effect of Coronal Flaring on Initial Apical File Size Estimation in Curved Canals Using Three Distinct Rotary Instruments: A Comparative In Vitro Study

“…Previous studies have mentioned that it is beneficial to eliminate coronal third obstruction before doing apical instrumentation. Multiple studies have suggested that modifying the upper third of the canals affects the dimensions of the file that fits tightly at the tip [ 14 , 15 ]. Advancements in this domain have led to the creation of novel types of rotary tools that are specifically engineered for cervical flaring.…”