B

Idiopathic bone cavity (simple/traumatic bone cyst) is a mandibular pseudocyst that consists of an empty or fluid-filled space without any epithelial lining, unlike true cysts such as dentigerous or keratocyst and unlike the blood-filled, fibrous-lined aneurysmal bone cyst [Kim, 2023, PMID 38174037; Kumar, 2015, PMID 26028875].