title: Ultrasonic versus high-speed cavity preparation: analysis of increases in pulpal temperature and time to complete preparation.
abstract: BACKGROUND
  The use of ultrasonic tips has become an alternative for cavity preparation. However, there are concerns about this type of device, particularly with respect to intrapulpal temperatures and cavity preparation time.
  
  
  OBJECTIVE
  The purpose of this study was to analyze pulpal temperature increases generated by an ultrasonic cavity preparation with chemical vapor deposition (CVD) tips, in comparison to preparation with a high-speed handpiece with a diamond rotary cutting instrument. The time required to complete the cavity preparation with each system was also evaluated.
  
  
  METHODS
  Thermocouples were positioned in the pulp chamber of 20 extracted human third molars. Slot-type cavities (3 x 3 x 2 mm) were prepared on the buccal and the lingual surfaces of each tooth. The test groups were: high-speed cavity preparation with diamond rotary cutting instruments (n=20) and ultrasonic cavity preparation with CVD points (n=20). During cavity preparation, the increases in pulpal temperature, and the time required for the preparation, were recorded and analyzed by Student's t test for paired samples (alpha=.05).
  
  
  RESULTS
  The average pulpal temperature increases were 4.3 degrees C for the high-speed preparation and 3.8 degrees C for the ultrasonic preparation, which were statistically similar (P=.052). However, significant differences were found (P<.001) for the time expended (3.3 minutes for the high-speed bur and 13.77 minutes for the ultrasound device).
  
  
  CONCLUSIONS
  The intrapulpal temperatures produced during cavity preparation by ultrasonic tips versus high-speed bur preparation were similar. However, the use of the ultrasonic device required 4 times longer for the completion of a cavity preparation.
authors.affiliation: Department of Dental Materials and Prosthodontics, São Paulo State University at São José dos Campos-UNESP, São Paulo, Brazil.
authors.forename: Aleska Dias
authors.initials: AD
authors.lastname: Vanderlei
authors.forename: Alexandre Luiz Souto
authors.initials: AL
authors.lastname: Borges
authors.forename: Bruno Neves
authors.initials: BN
authors.lastname: Cavalcanti
authors.forename: Sigmar Mello
authors.initials: SM
authors.lastname: Rode
mesh_terms: D001831:Body Temperature; D003737:Dental Cavity Preparation / Q000295:instrumentation* / Q000379:methods; D003754:Dental High-Speed Equipment; D003782:Dental Pulp / Q000502:physiology*; D018130:Diamond; D006801:Humans; D013997:Time Factors; D014465:Ultrasonics
chemical_list: D018130:Diamond