Castle Rock, Washington ... in the mid-eighties

Latest Update Saturday, January 17, 1998

Many teeth, especially lower molars, have two canals but only one common apex.

Generally, the way to test for this occurrence is to place one file in each canal alternately pushing one to the apex, then the other and testing to see of the other will also go.

If they won't it's because of that unique scientific phenomenon that two things cannot occupy the same space at the same time.

But there is another way. Dr. Bob Manthe of Castle Rock passes this on to you.

Radio Shack sells multi-meters for about $13. One of the functions is to test resistance.

If you touch one probe to one file and the other to the other file and those two files are touching, the resistance is zero ohms.

If both of those files are in canals, then the two canals converge. Simple.

After putting both files in the canals, the dental assistant touches the two probes to the two files and voila! Instant answers.

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