A tooth abscess or root abscess is pus enclosed in the tissues of the jaw bone at the tip of an infected tooth. Usually the abscess originates from a bacterial infection that has accumulated in the soft pulp of the tooth. This is usually, but not always, associated with a dull, throbbing, excruciating ache. A tooth abscess typically originates from dead pulp tissue, usually caused by untreated tooth decay, cracked...