POWERED SURGICAL DRILL WITH INTEGRAL DEPTH GAUGE THAT INCLUDES A PROBE THAT SLIDES OVER THE DRILL BIT

There is disclosed a transducer assembly configured to be coupled to a surgical drill handpiece having a drill housing surrounding a drill bit to measure a depth of a bore formed by the drill bit, said transducer assembly comprising: a shell configured to be coupled to the drill housing of the surgical drill; a probe being slidably mounted to the shell so as to extend forward from the shell and to retract into the shell; a gear rotatably coupled to the shell and configured to rotate in response to extension and retraction of the probe; and a transducer configured to generate signals responsive to rotation of the gear that are representative of a distance the drill housing moves relative to a distal end of the probe when the drill bit is operatively coupled to the surgical drill handpiece and the shell is coupled to the drill housing.