A computational simulation study on the acoustic pressure generated by a dental endosonic file: Effects of intensity, file shape and volume

• Acoustic pressure generated is affected by the working volume.
• Endosonic files were able to generate high acoustic pressures in a confined space.
• The acoustic pressure generated contributes to the production of cavitation.
• Decrease in size of the root canal model causes an increase in acoustic pressure.

One of the uses of ultrasound in dentistry is in the field of endodontics (i.e. root canal treatment) in order to enhance cleaning efficiency during the treatment. The acoustic pressures generated by the oscillation of files in narrow channels has been calculated using the COMSOL simulation package. Acoustic pressures in excess of the cavitation threshold can be generated and higher values were found in narrower channels. This parallels experimental observations of sonochemiluminescence. The effect of varying the channel width and length and the dimensions and shape of the file are reported. As well as explaining experimental observations, the work provides a basis for the further development and optimisation of the design of endosonic files.