Irrigant flow within a prepared root canal using various flow rates: a Computational Fluid Dynamics study

• Published in: International endodontic journal 2009-02, Vol.42 (2), p.144-155
• Main Authors: Boutsioukis, C., Lambrianidis, T., Kastrinakis, E.
• Format: Article
• Language: English
• Subjects: computational fluid dynamics; Computer Simulation; Dental Pulp Cavity - pathology; Dentistry; Equipment Design; flow rate; Humans; Image Processing, Computer-Assisted; irrigation; Models, Chemical; needle; Needles; Rheology; Root Canal Irrigants - chemistry; Root Canal Preparation - instrumentation; Software; Surface Properties; Syringes; Therapeutic Irrigation - instrumentation; Tooth Apex - pathology
• ISSN: 0143-2885; 1365-2591
• DOI: 10.1111/j.1365-2591.2008.01503.x

Aim  To study using computer simulation the effect of irrigant flow rate on the flow pattern within a prepared root canal, during final irrigation with a syringe and needle. Methodology  Geometrical characteristics of a side‐vented endodontic needle and clinically realistic flow rate values were obtained from previous and preliminary studies. A Computational Fluid Dynamics (CFD) model was created using FLUENT 6.2 software. Calculations were carried out for five selected flow rates (0.02–0.79 mL sec−1) and velocity and turbulence quantities along the domain were evaluated. Results  Irrigant replacement was limited to 1–1.5 mm apical to the needle tip for all flow rates tested. Low‐Reynolds number turbulent flow was detected near the needle outlet. Irrigant flow rate affected significantly the flow pattern within the root canal. Conclusions  Irrigation needles should be placed to within 1 mm from working length to ensure fluid exchange. Turbulent flow of irrigant leads to more efficient irrigant replacement. CFD represents a powerful tool for the study of irrigation.