Cleaning lateral morphological features of the root canal: the role of streaming and cavitation

J Robinson, R. G. Macedo, B. Verhaagen , M. Versluis, Paul Cooper, L. W. M. van der Sluis , Anthony Walmsley

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)
132 Downloads (Pure)


To investigate the effects of ultrasonic activation file type, lateral canal location and irrigant on the removal of a biofilm-mimicking hydrogel from a fabricated lateral canal. Additionally, the amount of cavitation and streaming was quantified for these parameters. 

An intracanal sonochemical dosimetry method was used to quantify the cavitation generated by an IrriSafe 25 mm length, size 25 file inside a root canal model filled with filtered degassed/saturated water or 3 different concentrations of NaOCl. Removal of a hydrogel, demonstrated previously to be an appropriate biofilm mimic, was recorded to measure the lateral canal cleaning rate from two different instruments (IrriSafe 25 mm length, size 25 and K 21 mm length, size 15) activated with a P5 Suprasson (Satelec) at power P8.5 in degassed/saturated water or NaOCl. Removal rates were compared for significant differences using non-parametric Kruskal– Wallis and/or Mann Whitney U tests. Streaming was measured using high-speed particle imaging velocimetry at 250 kfps, analysing both the oscillatory and steady flow inside the lateral canals. 

There was no significant difference in amount of cavitation between tap water and oversaturated water (P=0.538), although more cavitation was observed than in degassed water. The highest cavitation signal was generated with NaOCl solutions (1.0%, 4.5%, 9.0%) (P<0.007) and increased with concentration (P<0.014). The IrriSafe file outperformed significantly the K-file in removing hydrogel (P<0.05). Up to 64% of the total hydrogel volume was removed after 20 s. The IrriSafe file typically outperformed the K-file in generating streaming. The oscillatory velocities were higher inside the lateral canal 3 mm compared to 6 mm from WL, and were higher for NaOCl than for saturated water, which in turn was higher than for degassed water. 

Measurements of cavitation and acoustic streaming have provided insight into their contribution to cleaning. Significant differences in cleaning, cavitation and streaming were found depending on the file type and size, lateral canal location and irrigant used. In general, the IrriSafe file outperformed the K-file, and NaOCl performed better than the other irrigants tested. The cavitation and streaming measurements revealed that both contributed to hydrogel removal and both play a significant role in root canal cleaning.
Original languageEnglish
Pages (from-to)e55-e64
Number of pages10
JournalInternational Endodontic Journal
Issue numberS1
Early online date31 Jul 2017
Publication statusPublished - Jan 2018


  • lateral canal
  • cleaning
  • streaming
  • cavitation


Dive into the research topics of 'Cleaning lateral morphological features of the root canal: the role of streaming and cavitation'. Together they form a unique fingerprint.

Cite this