Which type of shank is NOT typically associated with a contra-angle handpiece?

A hexagonal shank is not typically associated with a contra-angle handpiece, primarily because it is designed for different types of instruments and applications. Contra-angle handpieces are known for their ability to provide operator comfort and visibility while working within a patient's oral cavity.

The latch-type shank is designed to work securely with the contra-angle handpiece, allowing for a firm grip during dental procedures. Similarly, the friction grip shank is also compatible, as it is designed to fit tightly within the handpiece to ensure stability when high-speed rotation is required.

Standard shank instruments can sometimes be used with various handpieces but are not specifically made for contra-angle applications. In contrast, the hexagonal shank is generally utilized in handpieces that require a different attachment method, making it unsuitable for use with a contra-angle handpiece that relies on the specific designs of latch-type or friction grip shanks for optimal function.