Pericoronitis is a condition in which the gum tissue becomes swollen and possibly infected around a tooth.  It is usually around a partially erupted wisdom tooth, most commonly on the lower arch.   When only part of the tooth has erupted into the mouth, it can create a flap of gum tissue that easily holds food particles and debris and is a hotbed for bacteria.

Symptoms can include painful, swollen gum tissue with possibly a bad smell or taste in the mouth.  There can even be a discharge of pus from the gums near the tooth.  Pericoronitis can be managed with antibiotics and warm salt water rinses.  However, if the partially erupted tooth does not completely enter the mouth, the food debris and bacteria will continue to accumulate under the flap of gums, and pericoronitis will more than likely return.  It is important to treat the cause of the problem so that it does not continue to occur.