In gum assessments, what change may put a patient at risk for tooth loss?

Gum recession is a significant change that can put a patient at risk for tooth loss because it involves the periodontal tissue pulling away from the tooth, exposing the roots. When the gums recede, the protective barrier provided by the gums is lost, which can lead to increased sensitivity, susceptibility to decay, and ultimately tooth instability or loss if not managed properly. As the gum tissue diminishes, the underlying structures that support the teeth may also become compromised, contributing to the potential for periodontal disease and tooth mobility.

In contrast, the other options, while they can indicate other forms of gum disease or oral health issues, do not directly imply the loss of gum tissue and its protective role in maintaining tooth stability. Patchy pigmentation, discoloration, and thick white patches might suggest various conditions or alterations in oral health but are not as directly linked to the structural integrity of the gums and the risk of tooth loss as gum recession is.