Benefits and disadvantages of impedance-ratio measuring method in new generation of apex-locators

Comparison of Electrical Equivalent Circuits of Human Tooth used for Measuring the Root Canal Length

“…Prior to this study we have used equivalent circuits with two or three linear elements (resistors and capacitors) to model the tooth [8,10,[12][13][14][15]. They could represent impedance behavior in a narrow frequency range, but their elements had to be frequency dependent in order to describe impedance in wider frequency range.…”

“…Various tooth morphology and the presence of irrigants used during the endodontic treatment influence the impedance of different tooth segments and cause inaccuracy of apex locators [2,4,8]. Influence of those physical parameters on the accuracy of apex locators can be minimized by measuring the impedance at more than one frequency [9,10].…”

“…In our previous work possibilities of using two-element and three-element equivalent circuits that include linear frequency-independent components were examined [8,10,[12][13][14][15]. Some authors have also proposed a few simpler [16] and more complex [17] equivalent circuits.…”