A 30 year old male presents to the OPD with pain in lower right tooth region with no remarkable medical history. Extra-oral examination reveals hard swelling corresponding to ramus of the mandible. On intra-oral examination 48 is absent. Aspiration reveals a thick, yellow cheesy material. OPG of patient is given below. What is the most probable diagnosis?

Clinical Features KOTs usually have no symptoms, although mild swelling may occur. Pain may occur  with  secondary  infection.  Aspiration  may  reveal  a  thick,yellow, cheesy material (keratin). In contrast to cysts, KOTs have a high propensity for recurrence, possibly because of small satellite cysts or fragments of epithelium left behind after surgical removal of the cyst. Differential Diagnosis When in a pericoronal position, a KOT may be indistinguishable from a dentigerous cyst. The lesion is likely to be a KOT if the cystic outline is connected to the tooth at a point apical to the cementoenamel junction or if no expansion of the cortical plates has occurred. Also, although KOTs can develop occlusal to developing teeth, often the follicle of the involved tooth is not enlarged as in dentigerous cysts. The typical scalloped margin and multilocular appearance of the KOT may resemble an ameloblastoma, but  the latter has a greater propensity to expand.  Radiographic interpretation- As with cysts, KOTs usually show evidence of a cortical border, unless they have become secondarily infected. The cyst may have a smooth, round or oval shape identical to that of other cysts, or it may have a scalloped outline (a series of contiguous arcs). Oral Radiology, Principles and Interpretation / Stuart C. White, Michael J. Pharoah - 7th ed pg- -343