J Korean Acad Conserv Dent.  2010 Jul;35(4):246-256. 10.5395/JKACD.2010.35.4.246.

An evaluation of rotational stability in endodontic electronic motors

• Park SH
• Seo HW
• Hong CU

• KMID: 2176378
• DOI: http://doi.org/10.5395/JKACD.2010.35.4.246

Abstract

The purpose of this study was to evaluate a rotational stability of endodontic electronic motors by comparing the changes of rotational speed, depending on the number of usages and with/without static load. Twelve new endodontic electronic motors were used in this study. Non contact type digital tachometer was used for measuring the rotational speed of handpiece. True RMS Multimeter was used for measuring the voltages and the electric currents. All measurements were recorded every 10 seconds during 10 minutes and repeated 9 times. Five repetition was done per each electronic motor. To statistical analysis, student t-test, repeated measures and Scheffe's post-hoc tests were performed. In the same motor group, there was no significant difference in all measurements. In all groups, there was no significant difference in the amount of rotational speed changes depending on the number of usages and with/without static load. In the limitation of this study, the results showed that all kinds of endodontic electronic motors in this study had an established rotational stability. Therefore they could be safely used in root canal treatment with a reliable maintenance of rotational speed, regardless of the number of usages and with/without load.

Keyword

Rotational stability; Electronic motor; Rotational speed; RPM; Endomate TC; X-Smart

MeSH Terms

Dental Pulp Cavity
Electronics
Electrons
Humans

Figure

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  Figure 1 Diagram of measuring method. a: Measurement of TECNIKA and AEU-25, under the unloading condition. b: Measurement of TECNIKA and AEU-25, under the loading condition. c: Measurement of X-Smart and Endomate TC, under the unloading condition. d: Measurement of X-Smart and Endomate TC, under the loading condition.

• 

  Figure 2 Actual rotational speed (rpm) of each electronic motors. horizontal axis: The number of measuring times (× 10 seconds), vertical axis: Rotational speed (RPM). a: Actual rotational speed of TECNIKA, under the unloading condition. b: Actual rotational speed of TECNIKA, under the loading condition. c: Actual rotational speed of AEU-25, under the unloading condition. d: Actual rotational speed of AEU-25, under the loading condition. e: Actual rotational speed of X-Smart (AC adapter), under the unloading condition. f: Actual rotational speed of X-Smart (AC adapter), under the loading condition. g: Actual rotational speed of X-Smart (Battery), under the unloading condition. h: Actual rotational speed of X-Smart (Battery), under the loading condition. i: Actual rotational speed of Endomate TC, under the unloading condition. j: Actual rotational speed of Endomate TC, under the loading condition.

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  Figure 3 Actual DC voltage (V) depending on repeated using. a: X-Smart (AC adapter) under the unloading condition. b: X-Smart (AC adapter) under the loading condition. c: X-Smart (Battery) under the unloading condition. d: X-Smart (Battery) under the loading condition. e: Endomate TC under the unloading condition. f: Endomate TC under the loading condition.

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  Figure 4 Actual DC current (mA) depending on repeated using. a: X-Smart (AC adapter) under the unloading condition. b: X-Smart (AC adapter) under the loading condition. c: X-Smart (Battery) under the unloading condition. d: X-Smart (Battery) under the loading condition. e: Endomate TC under the unloading condition. f: Endomate TC under the loading condition.

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