One month ago, a 63-year-old woman was treated for a dental abscess on her right lower jaw. Resolution was achieved with oral penicillin. However, a small red bump appeared on the overlying skin. The lesion developed into an erythematous papule with retracted surrounding skin. It appeared to be fixed to the underlying jaw structures. The patient noted that the growth was slightly tender to the touch, with occasional discharge. There was no accompanying fever, and the woman was otherwise healthy.

What is your diagnosis?

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