Periodonit (az peri… va yun. odontos — dandon), gazaki pardai resha va boftahoi atrofi dandon. Asosan badi kariesi dandon paydo meshavad. Ammo az takroran zarb khurdani dandon (masalan, az rui odat gazidani angusht, qalam, mekh, bo dandon kandani rishta va gayra) niz ba vujud meoyad.
Periodontit shadid va muzmin meshavad. Hangomi Periodontiti shadid dardi dandon jonkoh meshavad, kom, lab yo lunj varam mekunad va bazan harorati badan baland megardad. Dar mavridi Periodontit m u z m i n az dahon bui nokhush meoyad va bemor hangomi khurokkhuri norohat meshavad.
M u o l i j a: plomba kardan yo kandani dandon; agar fasod jam shuda boshad, chok kardani varam; istemoli antibiotikho.