What aspect of porcelain does overglazing NOT typically affect?

Overs glazing is a process applied to porcelain restorations, which primarily enhances their surface characteristics and aesthetic properties. While overglazing can impact aspects such as color change due to the presence of different materials and firing processes, it does not typically affect the porcelain's intrinsic resistance to temperature changes.

Temperature resistance in porcelain is largely determined by its composition and structure rather than by the superficial qualities modified through overglazing. Therefore, the material's fundamental ability to withstand thermal stress is maintained despite the application of an overglaze.

In contrast, overglazing may contribute to other aspects, like introducing risks of fracture due to changes in the surface integrity or altering the shine, which could make restorations look less natural. The bluish-grey color change can occur if the glazing material interacts unfavorably with the underlying porcelain. Thus, while overglazing can affect many surface properties, it does not compromise the thermal resistance of the porcelain itself.