Which of the following is NOT a common dental emergency?

Whitening treatment is not considered a common dental emergency because it is a cosmetic procedure that is typically planned and can be scheduled at the patient's convenience. Unlike dental abscesses, fractured teeth, and tooth avulsions—all of which require immediate attention due to pain, potential infection, or risk of losing a tooth—whitening is a non-urgent treatment focused on enhancing the appearance of teeth over time. This distinguishes it from the other scenarios listed, which present acute situations demanding prompt professional intervention to alleviate discomfort and prevent further complications.