title: Does cavitation occur around powered toothbrushes?
abstract: OBJECTIVE
  The aim of this investigation was to determine if cavitational activity occurred around powered toothbrushes using a chemical dosimeter system based on terephthalic acid (TA).
  
  
  METHODS
  Five powered toothbrushes were used in this investigation: Braun Plaque Remover D8, Braun Oral-B 3D, Philips Jordan Sensiflex HX2520, Sonicare PS-1 and Sonicare Elite HX 7351/02. Each brush head was inserted into a conical flask containing 50 cm3 of aqueous TA solution. Brushes were operated for 10 and 20 min and a cuvette of the solution was placed in a fluorescence spectrometer (Perkin Elmer 3000). The fluorescence emitted at wavelength 425 nm, which is proportional to *OH radical concentration, was monitored.
  
  
  RESULTS
  Any cavitational activity that may have been produced by the powered toothbrushes was below the limit of detection of the system (<10(-8) M) for the timescales investigated.
  
  
  CONCLUSIONS
  This work has demonstrated that cavitational activity does not occur around powered toothbrushes. Operating the toothbrushes for periods up to 20 min resulted in no cavitational activity being detected.
authors.affiliation: School of Dentistry, The University of Birmingham, St Chad's Queensway, Birmingham, UK. s.lea@bham.ac.uk
authors.forename: S C
authors.initials: SC
authors.lastname: Lea
authors.forename: G J
authors.initials: GJ
authors.lastname: Price
authors.forename: A D
authors.initials: AD
authors.lastname: Walmsley
mesh_terms: D004867:Equipment Design; D006801:Humans; D017665:Hydroxyl Radical / Q000737:chemistry; D008422:Materials Testing; D010795:Phthalic Acids / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013997:Time Factors; D014099:Toothbrushing / Q000295:instrumentation*; D014618:Vacuum
chemical_list: D010795:Phthalic Acids; D017665:Hydroxyl Radical; C011363:terephthalic acid