Microfluidics and Nanofluidics

, Volume 16, Issue 6, pp 1165–1177 | Cite as

Irrigant transport into dental microchannels

  • B. Verhaagen
  • C. Boutsioukis
  • C. P. Sleutel
  • E. Kastrinakis
  • L. W. M. van der Sluis
  • M. Versluis
Research Paper


The root canal system of a tooth is a complex geometrical entity, consisting not only of the main root canal, but also of accessory and lateral canals. Bacteria can reside up to hundreds of micrometers inside those channels and may be difficult to reach for the antimicrobial agents with which root canals are irrigated during a root canal treatment. A combined numerical and experimental study was performed to assess the penetration rate of a root canal irrigant into the lateral canals and tubules, considering both diffusion and convection. The numerical model was validated experimentally using a fluorescent dye. Convection was studied separately using a Computational Fluid Dynamics model, validated with Particle Imaging Velocimetry experiments. Both diffusion and convection were found to be slow on the timescale of an irrigation procedure. The contribution of convection was limited to two canal diameters from the canal entrance, making diffusion the main irrigant transport mechanism. More than 10 min of fresh irrigant delivery was required to obtain an 86 % concentration of the irrigant at the far end of a tubule, in the ideal case of a straight tubule without reaction taking place. Diffusion was even slower when the concentration at the lateral canal entrance was not kept constant, as in the case of a single delivery, which suggests that frequent irrigant replenishment and/or irrigant activation during a root canal treatment are beneficial. Alternative methods should be considered to improve irrigant penetration into lateral canals and tubules.


Endodontics Transport Lateral canals Cavity flow Diffusion 



This study was funded through Project 07498 of the Dutch Technology Foundation STW (B.V.) and a Marie Curie Intra-European Fellowship for Career Development (C.B.). The authors are grateful to R.G. Macedo and Prof. L. Lefferts for valuable discussions; Assoc. Prof. L. Vasiliadis is acknowledged for the SEM images.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • B. Verhaagen
    • 1
  • C. Boutsioukis
    • 2
  • C. P. Sleutel
    • 2
  • E. Kastrinakis
    • 3
  • L. W. M. van der Sluis
    • 4
  • M. Versluis
    • 1
    • 2
  1. 1.Physics of Fluids Group and Institute for Biomedical Technology and Technical Medicine MIRAUniversity of TwenteEnschedeThe Netherlands
  2. 2.Physics of Fluids Group and MESA+ Institute for NanotechnologyUniversity of TwenteEnschedeThe Netherlands
  3. 3.Department of Chemical Engineering, Polytechnic SchoolAristotle University of ThessalonikiThessaloníkiGreece
  4. 4.Center for Dentistry and Oral HygieneUniversity Medical Center GroningenGroningenThe Netherlands

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