| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem in which a measuring needle is moved up and down and further revolved at the time of measurement of the length of the root canal to also perform work of the expansion or the like of the root canal but, since a holder cylinder for clipping the measuring needle is constituted of resin, the leading end part of the holder cylinder is shaven by the rotation of the measuring needle, the holding force of the measuring needle lowers and foreign matter further becomes easy to get mixed in the holder cylinder from the shaved place. <P>SOLUTION: A dental root canal length measuring instrument is electrically detected that the tip of the conductive root canal length measuring needle 1a reaches the root apex and the push-in depth of the root canal length measuring needle into the root canal 3 at this time is replaced with the stopper 4 provided to the root canal length measuring needle 1a in a freely movable manner to measure the length of the root canal 3 from the length from the tip of the root canal length measuring needle 1a to the stopper 4. A measuring electrode wire having the clip part 6a brought into contact with the root canal length measuring needle 1a is inserted into the leading end part and the leading end part has a measuring needle clip holder cylinder 11 made of resin cooperated with the clip part 6a to hold the root canal length measuring needle 1a. The outer surface of the tip part 11' of the holder cylinder 11 is coated with a metal. <P>COPYRIGHT: (C)2012,JPO&INPIT |
