Abstract
With regard to the present electronic method for measuring the root canal length, various studies are being carried out especially on variable factors having effects on measured values, purposing to establish more accurate measuring method.But, it still involves many problems to be solved.The author, in the present study purposing to get fundamental data showing the phases of change in meter-indicating values that appear in case the reamer is inserted into a root canal in the process of measuring its length by the present electronic method, using glass tubes in place of root canals to be erected in the normal saline solution used as electrolytic solution, into which inserts uncovered or covered electrode made of stainless steel wire the same material as of reamer, to measure and record the change in impedance by the electronic apparatus for measuring the root canal length on the market, and examined the effects of the surface area of electrode contacted with the solution and the inner diameter of glass tube.The following results were obtained.The glass tube functioned as impedance and its effect became larger, in case it was smaller in inside diameter.The covered electrode, different from the uncovered one, had a fixed surface area to be in contact with the solution.Consequently, when it was inserted into the glass tube in the solution, the meter-indicating value became low, and constant without fail once the electrode came out of the glass tube.
