The impression automix system is used for each, EXCEPT one. Which is the EXCEPTION?

The impression automix system is a convenient and efficient way to dispense and mix impression materials for dental procedures. It is typically used for applications that require precise mixing and the right consistency of the material.

In the context of the options given, the automix system is designed for use with syringe material, tray material, and bite registration. These materials benefit from the accuracy and ease of use that the automix system provides, allowing for controlled dispensing and consistent mixing, which is critical for achieving the desired properties for effective impressions in dentistry.

However, putty wash materials, while they may also be used in conjunction with other impression materials, are typically mixed by hand rather than being dispensed through an automix system. The nature of putty wash requires a different handling technique that is not suited for the automix dispensing method, which is why it is the exception among the listed options. This manual mixing allows for the necessary adjustments in viscosity and consistency that are often required in clinical situations when adhering to specific impression techniques.