The last tooth in the mouth is swollen and painful, if it is wisdom tooth pericoronitis, you need to rinse the local medicine, if it is pulpitis, apical periapical inflammation, you need to carry out root canal treatment. 1. Wisdom tooth pericoronitis: Wisdom teeth are located at the end of the tooth row, there are often blocked, easy to trigger wisdom tooth pericoronitis, generally use hydrogen peroxide and saline alternately rinse the gingival pocket, local povidone-iodine medication, and to be considered in the chronic phase after the removal of wisdom teeth. 2. Pulpitis, periapical inflammation: If the tooth pain is in the acute stage, pulpitis, periapical inflammation of the need for endodontic treatment to open the pulp drainage, to be turned into a chronic period after the wisdom teeth are recommended to be removed, and if it is the other molar need to carry out the next step of endodontic treatment. Swelling and pain of teeth in the oral cavity is recommended to seek medical treatment in a timely manner to avoid the spread of inflammation caused by interstitial infection.