We randomly assigned college students to conditions in which they learned that they had gum disease, were at risk of having gum disease, or did not have gum disease. Then we examined their coping responses both immediately after the diagnosis and 2 days later. Students that told they had gum disease saw the disease as more prevalent than students in the other conditions; students identified as at risk saw the disease as more common than students who were told they had no disease. In addition, disease and at-risk diagnosis subjects believed that the disease was less serious but, during the 2-day interval between tests, they reported experiencing more bleeding–a symptom of gum disease. All of these responses to diagnosis were similar immediately after diagnosis and 2 days later. The data support a model of how persons react to illness signs (Ditto, Jemmott, & Darley, 1988) and have practical implications for dental professionals involved in diagnosing gum disease.