Odontogenic cyst. Light micrograph (LM) of inflammation within an odontogenic cyst. Large numbers of inflammatory sells including polymorphonuclear neutrophils (PMN) are present. Odontogenic cyst are a group of jaw cysts that are formed from tissues involved in odontogenesis (tooth development). Odontogenic cysts are closed sacs, and have a distinct membrane derived from rests of odontogenic epithelium. It may contain air, fluids, or semi-solid material. Magnification: x160 when printed 10cm wide.