Postdoctoral Program in Prosthodontics, Department of Endodontics, Prosthodontics, and Operative Dentistry, Baltimore College of Dental Surgery, University of Maryland, Baltimore, MD, USA.
J Prosthet Dent. 2010 Feb;103(2):101-7. doi: 10.1016/S0022-3913(10)60013-3.
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.
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.
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 (alpha=.05).
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).
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.
牙科正逐渐倾向于更多地使用电动手机。牙科医生应该有足够的证据来验证从空气涡轮机手机切换到电动手机的合理性。然而，很少有研究量化电动和空气涡轮机手机的切割效率。那些确实量化切割效率的研究通常也只是针对单一材料。
本研究的目的是比较电动手机和空气涡轮手机在使用牙科中常用的各种材料时的切割效率。
七种材料：Macor（可加工玻璃陶瓷）、银汞合金、氧化铝、氧化锆、高贵金属合金、贵金属合金和贱金属合金，每种材料用磨头切割 220 次；电动手机切割 110 次，空气涡轮手机切割 110 次。通过从切割前的材料重量中减去切割后的材料重量来计算材料的重量差。通过将重量差除以切割持续时间（g/s）来计算切割效率。数据通过双因素方差分析和 Tukey 的 Honestly Significant Difference（HSD）检验（α=.05）进行分析。
电动手机的切割效率高于空气涡轮手机（F=3098.9，P<.001）。特别是高贵金属合金、银汞合金和 Macor 用电动手机切割的效率更高（分别为 0.0383 +/-0.0002 g/s、0.0260 +/-0.0002 g/s 和 0.0122 +/-0.0002 g/s），而用空气涡轮手机切割的效率较低（分别为 0.0125 +/-0.0002 g/s、0.0142 +/-0.0002 g/s 和 0.008 +/-0.0002 g/s）。
与空气涡轮手机相比，电动手机在切割牙科中使用的各种材料（特别是可加工玻璃陶瓷、银汞合金和高贵金属合金）方面效率更高。
