Effect of Gates Glidden, La Axxess, SX and ultrasound on the circularity and area of mesial canals of mandibular molars

Resumo

Biomechanical preparation must provide a taper
shape at crown-apex direction for root canal resulting in adequate
space for irrigation and enabling an effective obturation. However,
this stage requires a cervical preparation aiming to remove the
interferences to make the access to the apical portion easy for
instrumentation. Objective: To evaluate in vitro the effect of coronal
flaring on the root canal area and in the circularity of mesial
canals of lower molars after using Gates Glidden, La Axxess, Sx
file or a ultrasonic TU-24tip. Material and methods: Twenty-four
lower molars had their roots embedded into acrylic resin. Then
the roots were sectioned horizontally at 2 mm below the cementenamel junction. The sections were photographed before and after
the different coronal flaring. All images were analyzed using Image
J software to calculate the root canal area and the circularity of
the root canal. One-way Anova was used to compare the circularity
among the groups, while Kruskal-Wallis test was used for comparing
the areas. A Pearson test was used to correlate root canal area
and circularity data. Results: There was no significant difference
among the groups neither for the circularity (p > 0.05) nor for the root canal area (p > 0.05). There was observed a significant inverse
correlation between the root canal area and the circularity (r2 =
0.135; p < 0.05). Conclusion: Different coronal flaring techniques
have produced similar root canal area and circularity, however the
larger the canal area the lower the circularity.