A dental abscess is an infection at the base of a tooth. It means a fund of pus has formed at the tip of a tooth root in your jawbone.However, it can spread to the goo near the tooth, If the infection is not treated. This causes swelling and pain. More serious infections spread to the face. This causes your face to swell (cellulitis). This is a veritably serious condition. Once the lump begins, it can spread snappily. A dental abscess generally starts with a crack or depression in a tooth. The pain is frequently made worse by drinking hot or cold potables, or smelling on hard foods. The pain may spread from the tooth to your observance or the area of your jaw on the same side.