Oral Medicine OSCE Questions-Guess the condition

This patient is a 28 year old male presented to the clinic with a 1 month history of chronic ulceration. n. The oral ulceration caused the patient considerable discomfort and significantly affected his normal oral function. ulcers appeared spontaneously and there was no improvement with the medication he had.Initially lesions appear as blisters and they coalesce to make a ulcer. His past medical history was not significant. Intra oral examination revealed that bilateral buccal mucosa, Gingiva and palate is affected with similar type of ulcers on the lips. Dermatologist confirmed that the patient had cutaneous lesions.

Guess the condition ???

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