Numerous symptoms will signal if an infection is present in the body. A strong indicator of infection is fever, which is considered a temperature over 100.4 degrees Fahrenheit. With an infection, your pain will likely be more severe and can radiate through the jaw, temporomandibular joint (TMJ), and ear. In addition, you may notice your tooth to be more sensitive to temperature and food. Swelling is another common sign of a tooth infection. Swelling may be seen in two places, the cheeks, and jaw, as a result of inflammation or in the lymph nodes around the face and neck, which is caused by increased immunity activity when an infection is present.