In implant site preparation, the surgeon uses the B20-8 between the surgical motor and the drill. The motor supplies the rotation, and the fixed gear train delivers one revolution at the chuck for every twenty at the input. This relationship remains the same as the motor speed changes. The external line supplies coolant to the working instrument as the surgeon positions the head at the site.
Different stages of an implant procedure can call for drills with different cutting diameters. The relevant fit at the handpiece is the shank diameter, the portion held by the chuck. Two compatible drills can share that dimension while their cutting ends differ. The operator can release one with the button, fit the next and keep the body sections locked throughout the change.
The handpiece also has a role away from the chair. After use, the team responsible for instrument care can separate its body by hand. That gives access to the parts of the drive enclosed during surgery and to the surfaces where the sections meet. The lock therefore serves a different purpose from the release button used to exchange drills during the case.
At the working end, the double seal limits the path debris can take into the head as the instrument rotates. The external spray line follows the neck towards the bur, with the coolant outlet positioned alongside the working end. For a dental surgery using this combination of drill fit and irrigation, the same attachment reduces speed during the procedure and provides access to the mechanism during subsequent maintenance.