Effect of Movement Kinematics and Heat-Treated Alloys on the Apical Extrusion of Debris: An In Vitro Study.

Background: Apically extruded debris can be affected by some features of the file systems such as kinematics or metallurgic properties.

Aims: This in vitro study aimed to evaluate the effect of movement kinematics (reciprocation or rotation) and heat-treated alloys (C.Wire) on the amount of debris extrusion.

Methods: Seventy-two mesiobuccal root canals were assigned into three experimental groups related to the single-file system used (n = 24): two rotational; One Shape (Conventional Ni-Ti), One Curve (C.Wire), and one reciprocating; and One Reci (C.Wire). The file systems were used according to the advisable speed and torque according to the manufacturers' suggestion. The weight of debris was calculated by subtracting the preweights from postweights of Eppendorf tubes. Kruskall-Wallis and Mann-Whitney U tests were used to analyze the data (P = 0.05).

Results: One Shape produced the greatest amount of extruded debris compared with One Curve (P < 0.001) and One Reci (P < 0.001), respectively. No statistical difference was found between One Curve and One Reci concerning amount of apical debris extrusion (P = 0.489).

Conclusion: Metallurgical properties of files may affect apical debris extrusion. Alloy type is an important factor in the amount of debris extrusion. File kinematics does not affect apical debris extrusion.