An<unk>  is a rare and benign but locally aggressive developmental cyst. It most often affects the posterior mandible and most commonly presents in the third decade of life.<unk> s make up around 19% of jaw cysts. In the WHO/IARC classification of head and neck pathology, this clinical entity had been known for years as the<unk> ; it was reclassified as<unk> ic<unk>  tumour (KCOT) from 2005 to 2017. In 2017 it reverted to the earlier name, as the new WHO/IARC classification reclassified<unk>  back into the cystic category. Under The WHO/IARC classification,<unk>  underwent the reclassification as it is no longer considered a neoplasm due to a lack of quality evidence regarding this hypothesis, especially with respect to clonality. Within the Head and Neck pathology community there is still controversy surrounding the reclassification, with some pathologists still considering<unk>  as a neoplasm in line with the previous classification.
Odontogenic keratocyst
Dentigerous cyst
Glandular odontogenic cyst
Cholesteatoma
Pseudolymphoma
Aquarium granuloma
Enamel pearl
Idiopathic facial aseptic granuloma