Influence of Glide Path on Apically Extruded Debris in Curved Root Canals During Root Canal Preparation Using Three Different Single-file Instrumentation Systems with Improved Alloy Technology: An In Vitro Study

The apically extruded debris (AED) is an unwanted complication during root canal preparation, especially in curved canals.

This study aimed to assess the impact of the glide path on the quantity of AED during root canal preparation with three different single-file systems with improved alloy technology in extremely curved canals.

One hundred and twenty maxillary first molar teeth with mesiobuccal root curvature (25°-45°) were randomly assigned to six groups (n=20). No glide path was created in three groups, whereas in the remaining three groups, a glide path was established in the mesiobuccal canals. Root canal instrumentation of the mesiobuccal canals was performed using three single-file systems: Reciproc Blue (RCB), WaveOne Gold (WOG), and TruNatomy (TN). AED was collected in pre-weighed Eppendorf tubes, which were subsequently stored in an incubator at 37 °C for two weeks. The weight of the dry extruded debris was determined by subtracting the pre-instrumentation weight from the post-instrumentation weight of the Eppendorf tubes. Statistical analysis was conducted using the Kruskal-Wallis test followed by Dunn’s post-hoc test with Holm correction (p<0.05).

RCB and WOG without glide path extruded significantly more debris than other groups (p<0.05). The canal preparation required significantly less time in teeth with a glide path than the teeth without a glide path (p<0.05).

Glide path preparation enhances shaping efficiency and significantly reduces apically extruded debris, especially in curved canals. The results of this in vitro study, along with existing literature, support the incorporation of glide path preparation into routine protocols to improve clinical outcomes. These findings may be translated into clinical practice to enhance endodontic treatment predictability and safety.

Within the limitations of this in vitro study, all tested instruments caused debris extrusion. A glide path significantly reduced the amount of AED and the preparation time. TN files extruded less debris compared with RCB and WOG.