title: The influence of grain size coating and shaft angulation of different diamond tips on dental cutting.
abstract: OBJECTIVE
  To evaluate the influence of the grain size coating and shaft angulation of ultrasonic and high-speed diamond burs on the dental cutting effectiveness.
  
  
  METHODS
  For the grain size evaluation, cavities were prepared on 40 incisors using high-speed (1092 and 1093F KG Sorensen(®)) and ultrasonic tips (8.2142 and 6.2142-CVDentus(®)). For the shaft angulation evaluation, cavities were prepared on 40 incisors using uniangulated (T1-CVDentus(®)) and biangulated (T1-A CVDentus(®)) ultrasonic tips. The cavities were bisected and examined at ×50 magnification. The width and depth of cavities were measured by Leica QWin software. Kruskal-Wallis non-parametric test was used for analysis.
  
  
  RESULTS
  The grain size did not affect the cutting effectiveness, but the high-speed burs promoted deeper and wider cavities than the ultrasonic tips. The shaft angulation did not affect the cutting effectiveness; both the angulated and biangulated tips had greater cutting efficiency in dentin than in enamel.
  
  
  CONCLUSIONS
  Ultrasonic tips promoted more conservative preparations and seemed promising for cavity preparation.
authors.affiliation: Department of Pediatric Dentistry, Araraquara Dental School, UNESP - Univ Estadual Paulista, Araraquara, SP, Brazil.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Santos-Pinto
authors.forename: Carolina Carvalho
authors.initials: CC
authors.lastname: Bortoletto
authors.forename: Ana Carolina Mascarenhas
authors.initials: AC
authors.lastname: Oliveira
authors.forename: Ary
authors.initials: A
authors.lastname: Santos-Pinto
authors.forename: Angela Cristina Cilense
authors.initials: AC
authors.lastname: Zuanon
authors.forename: Luciana Monti
authors.initials: LM
authors.lastname: Lima