A 13 year old boy presents to OPD with pain in lower right tooth region with no remarkable medical history. On intraoral examination, 85 was found to be carious and did not respond to EPT. Radiographs taken are shown below. What is the most probable diagnosis?

Radicular cysts are the most common type of cyst in the jaws. They arise from nonvital teeth  (i.e., teeth that have necrotic pulps because of extensive caries, large restorations, or previous trauma). Radicular cysts often produce no symptoms unless secondary infection occurs. A cyst that becomes large may cause swelling.