Reducing Apical Bacterial Extrusion: The Impact of Reciproc File Size and Irrigation Technique

Area of Science:

• Endodontics
• Microbiology

Background:

• Apical bacterial extrusion is a concern in root canal preparation.
• Reciproc files are widely used, but their impact on extrusion needs evaluation.

Purpose of the Study:

• To compare apical bacterial extrusion using Reciproc files 25/0.08 and 40/0.06 with different irrigation techniques.

Main Methods:

• Seventy human premolars contaminated with Enterococcus faecalis were instrumented with Reciproc 25/0.08 or 40/0.06.
• Irrigation methods included conventional syringe irrigation and passive ultrasonic irrigation (PUI) with one or two activation cycles.
• Extruded debris was collected, cultured, and quantified as colony-forming units (CFU/mL).

Main Results:

• Instrumentation with Reciproc 25/0.08 resulted in significantly higher bacterial extrusion compared to Reciproc 40/0.06 (P<0.05).
• Passive ultrasonic irrigation (PUI) further increased bacterial extrusion when used with the smaller Reciproc 25/0.08 file.

Conclusions:

• All tested instrumentation techniques led to apical bacterial extrusion.
• Using larger file sizes, such as Reciproc 40/0.06, was associated with reduced apical bacterial extrusion.