Comparing the Coronal Flaring Efficacy of Five Different Instruments Using Cone-Beam Computed Tomography.
INTRODUCTION
Fearless removal of tooth structure during canal preparation and shaping has negative effects on the prognosis of treatment. On the other hand, sufficient pre-enlargement facilitates exact measurement of the apical size. The present in vitro study aimed to compare the efficacy of Gates-Glidden drills, K3, ProTaper, FlexMaster and RaCe instruments in dentin removal during coronal flaring using cone-beam computed tomography (CBCT).


METHODS AND MATERIALS
A total of 40 mandibular molars were selected and the coronal areas of their mesiobuccal and mesiolingual root canals were randomly prepared with either mentioned instruments. Pre- and post-instrumentation CBCT images were taken and the thickness of canal walls was measured in 1.5- and 3-mm distances from the furcation area. Data were analyzed using the one-way ANOVA. Tukey's post hoc tests were used for two-by-two comparisons.


RESULTS
At 1.5-mm distance, there was no significant difference between different instruments. However, at 3-mm distances, Gates-Glidden drills removed significantly more dentin compared to FlexMaster files (mean=0.18 mm) (P<0.02); however, two-by-two comparisons did not reveal any significant differences between the other groups.


CONCLUSION
All tested instruments can be effectively used in clinical settings for coronal pre-enlargement.
['Homayoon|Amin|A|', 'Hamidi|Mahmood Reza|MR|', 'Haddadi|Azam|A|', 'Madani|Zahra Sadat|ZS|', 'Moudi|Ehsan|E|', 'Bijani|Ali|A|']
Coronal Flaring Cone-Beam Computed Tomography Coronal Pre-Enlargement Root Canal Preparation Root Canal Treatment