title: Noise levels in dental schools.
abstract: OBJECTIVE
  To measure and analyse noise levels in the learning-teaching activities at the Dental School of the University of Porto (Portugal).
  
  
  METHODS
  Sound levels were measured in five different practice areas and laboratories, selected as representative of a variety of learning-teaching activities. The noise levels were determined using a precision sound level meter that was positioned at ear level and at 1 m distance from the operator.
  
  
  RESULTS
  The noise levels registered vary between 60 and 99 dB(A) and are similar to the data of other international studies. The results recorded differences in sound levels when the equipment was merely turned on and during cutting operations. Differences between brand new and used equipment were also noted. It appears that hearing damage risk may be lesser amongst dentists who use brand new equipment.
  
  
  CONCLUSIONS
  The noise levels detected in this study are considered to be close to the limit of risk of hearing loss.
authors.affiliation: Department of Fixed Prosthesis, Faculty of Dentistry, University of Porto, Portugal.
authors.forename: J C
authors.initials: JC
authors.lastname: Sampaio Fernandes
authors.forename: A P O
authors.initials: AP
authors.lastname: Carvalho
authors.forename: M
authors.initials: M
authors.lastname: Gallas
authors.forename: P
authors.initials: P
authors.lastname: Vaz
authors.forename: P A
authors.initials: PA
authors.lastname: Matos
mesh_terms: D000162:Acoustics / Q000295:instrumentation; D003740:Dental Clinics; D003748:Dental Equipment; D003754:Dental High-Speed Equipment; D006801:Humans; D007754:Laboratories, Dental; D009623:Noise, Occupational; D011174:Portugal; D011476:Prosthodontics / Q000295:instrumentation; D012307:Risk Factors; D012575:Schools, Dental