Pus forms when the immune system's white blood cells fight an infection. Pus can be different colors and may emit a foul odor if the infection is severe. Larger abscesses usually need to be drained ...

Cutaneous dental (or odontogenic) sinus tracts are uncommon occurrences in which a channel forms from a dental focus of infection to a drainage site on the skin of the face or neck. Odontogenic sinus ...