PURPOSE:

To assess the vibration characteristics of oscillating objects with the scanning laser vibrometer (SLV). A laser is scanned over the surface of a vibrating target and the reflected, Doppler frequency shifted beam is used to determine the displacement amplitude and frequency of the vibration. This communication reports on a preliminary investigation to assess unloaded powered toothbrush oscillations, using Scanning Laser Vibrometry.

METHODS:

Four powered toothbrushes were selected for this study including the Sonicare, Philips/Jordan Sensiflex HX2520, Braun 3D and Braun D8. Each toothbrush was clamped in position and 10 area scans of their heads were taken from the side orientation to determine the displacement amplitude and frequency of oscillation.

RESULTS:

The fundamental frequency of oscillation of each brush was determined: Sonicare: 262.5Hz; Philips: 62.5Hz; 3D: 75Hz and D8: 62.5Hz. The maximum displacement amplitude (half the peak-to-peak excursion) for each brush (at the tips of the longest bristles) was Sonicare; 2.51 +/- 0.32mm, Philips; 2.60 +/- 0.15mm, Braun 3D; 2.14 +/- 0.18mm and Braun D8; 2.14 +/- 0.21.