Comparison of cutting efficiencies between electric and air-turbine dental handpieces
Statement of problem
Dentistry is gravitating toward the increased use of electric handpieces. The dental professional should have sufficient evidence to validate the switch from an air-turbine handpiece to an electric handpiece. However, there is little research quantifying the cutting efficiency of electric and air-turbine handpieces. Studies that do quantify cutting efficiency typically do so with only a single material.
Purpose
The purpose of this study was to compare the cutting efficiency of an electric handpiece and an air-turbine handpiece, using various materials commonly used in dentistry.
Material and methods
Seven materials: Macor (machinable glass ceramic), silver amalgam, aluminum oxide, zirconium oxide, high noble metal alloy, noble metal alloy, and base metal alloy, were each cut with a bur 220 times; 110 times with an electric handpiece, and 110 times with an air-turbine handpiece. The weight difference of the material was calculated by subtracting the weight of the material after a cut from the weight of the material before the cut. The cutting efficiency was calculated by dividing the weight difference by the duration of the cut (g/s). Data were analyzed by a 2-way analysis of variance followed by Tukey's Honestly Significant Difference (HSD) test (α=.05).
Results
The electric handpiece cut more efficiently than the air-turbine handpiece (F=3098.9, P<.001). In particular, the high noble metal alloy, silver amalgam, and Macor were cut more efficiently with the electric handpiece (0.0383 ±0.0002 g/s, 0.0260 ±0.0002 g/s, and 0.0122 ±0.0002 g/s, respectively) than with the air-turbine handpiece (0.0125 ±0.0002 g/s, 0.0142 ±0.0002 g/s, and 0.008 ±0.0002 g/s, respectively).
Conclusions
The electric handpiece is more efficient at cutting various materials used in dentistry, especially machinable glass ceramic, silver amalgam, and high noble alloy, than the air-turbine handpiece.
aFormer Prosthodontic Resident, Postdoctoral Program in Prosthodontics, Department of Endodontics, Prosthodontics, and Operative Dentistry, Baltimore College of Dental Surgery, University of Maryland, Baltimore, Md
bProfessor, Program Director, Advanced Education Program in Prosthodontics, Department of Endodontics, Prosthodontics, and Operative Dentistry, Baltimore College of Dental Surgery, University of Maryland, Baltimore, Md
cProfessor, Department of Health Promotion and Policy, Baltimore College of Dental Surgery, University of Maryland, Baltimore, Md
Corresponding author: Dr Carl F. Driscoll, University of Maryland Dental School, 666 W Baltimore St, Rm 3-D-08, Baltimore, MD 21201, Fax: 410-706-3028
Supported by the American Academy of Fixed Prosthodontics, Tylman Research Grant, July 2005.
ABSTRACT