/per'ee oh don tuy"tis/ , n. Dentistry.
inflammation of the periodontium caused by bacteria that infect the roots of teeth and the surrounding gum crevices, producing bleeding, pus formation, and gradual loss of bone and the tissues that support the teeth. Cf. pyorrhea (def. 2).
[ 1870-75; PERIODONT(IUM) + -ITIS ]