<prompt> All are exploring instruments for a root canal except:DG-16JK-17CK-17JW-17  <response>: The DG-16 endodontic explorer is used to identify canal orifices and to determine canal angulation.The CK-17 endodontic explorer serves the same purpose, but its thinner, stiffer tip can be useful for identifying calcified canals.Micro JW-17 - Thin Canal Explorer, Double-Ended, Single instrument.JK-17 - Dental explorer or sickle probe. 