An instrument for measuring root canal length and apex location. A rapid technique

The invention of a new instrument (the Apexfinder) for measuring the root length and apex location is reported. This instrument is an accurate and reliable tool for the apex determination. The application method is based on the insertion of a plastic, fine-tapered barbed shaft through a beveled tube into the root canal. When resistance to withdrawal is felt, which indicates that one of the barbs has engaged the apical margin, the shaft is marked at the level of the cusp tip. The distance between the mark and the barbs which caused the resistance is measured. These barbs will show apical inclination, which would be opposite to the direction of the rest of the barbs. The practitioner can rely on this technique in the majority of cases provided that a full range of plastic shafts, with different dimensions, is available for use with the outer tube.