title: Comparison of the efficiency of four different ultrasonic tips to remove dentin over time.
abstract: BACKGROUND
  The objective of this study was to compare the efficiency of 4 ultrasonic tips to remove dentin from sectioned third molars.
  
  
  METHODS
  The 4 groups (n = 5) were as follows: ET-18D, BUC-1, TUFI-2, and P5. A P5 Newtron XSTM ultrasonic unit was used. A universal tester applied a downward force of 15g, previously determined in a pilot study, in cycles of 20 seconds for a total of 4 minutes of instrumentation time. Efficiency was measured by change in weight of the dentin specimen measured to the nearest 0.01 mg after 2 and 4 minutes of instrumentation.
  
  
  RESULTS
  There was no statistically significant difference in dentin removal between measurement times for any tip (P>.05). There was a statistically significant difference in dentin removal as a function of tip type (P=.0001), with the BUC-1 tip removing significantly more dentin across time.
  
  
  CONCLUSIONS
  On the basis of the results, the BUC-1TM tip removes dentin more efficiently than the other tips tested.
authors.affiliation: Department of Endodontics, University of Missouri-Kansas City, School of Dentistry, Kansas City, Missouri 64108, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Yelton
authors.forename: Kerri
authors.initials: K
authors.lastname: Lawlor
authors.forename: James C
authors.initials: JC
authors.lastname: Kulild
authors.forename: Mary P
authors.initials: MP
authors.lastname: Walker
mesh_terms: D003762:Dental Instruments; D003804:Dentin / Q000601:surgery*; D004867:Equipment Design; D006801:Humans; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D013997:Time Factors; D014464:Ultrasonic Therapy / Q000295:instrumentation* / Q000379:methods