What does the term syneresis refer to regarding impression material?

The term syneresis specifically refers to the process where an impression material experiences shrinking and distortion as a result of evaporation. This phenomenon typically occurs when the water content within the impression material begins to evaporate, causing the material to lose volume and potentially altering its shape and accuracy.

In the context of dental impressions, syneresis is a critical consideration because it can impact the precision of the mold created for procedures like crown fittings or dentures. Understanding this process helps dental professionals manage impression materials more effectively, ensuring that the final outcomes align with the intended treatment plans.

The other choices relate to different processes or characteristics of impression materials that do not accurately define syneresis. For instance, hardening and cooling pertain to the setting reactions of dental materials, while mixing refers to the preparation of those materials prior to application.