What feature of a temporary crown can negatively affect gingival health?

Overcontouring a temporary crown can negatively affect gingival health because it can lead to gum irritation and inflammation. When a crown is overcontoured, it may extend beyond the ideal contour and shape of the natural tooth, causing excess pressure on the surrounding gingival tissue. This results in a situation where the gum can become compressed or traumatized, leading to discomfort, inflammation, and potential long-term health issues for the gingiva.

In contrast, undercontouring does not generally create the same level of irritation, as it does not impose excess pressure on the gum tissues. A crown that is the right size and is made from proper materials would typically support gingival health as they maintain the correct anatomical relationships and are less likely to provoke adverse reactions in the surrounding tissues. Thus, overcontouring stands out as a critical factor that can detrimentally impact the health of the gums.