Impaction commonly affects mandibular third molars. An inverted impacted mandibular premolar is rare.
We describe an inverted impacted mandibular premolar, the crown of which was exposed from the lower border of the mandible. The patient was a 67-year-old man with swelling and spontaneous pain of the left submandibular area. Radiographic examination showed dental material restoration at the apex of the inverted impacted mandibular premolar. After antibiotic chemotherapy, incision, and drainage, an operation was done from an extraoral approach with the patient under general anesthesia. An incision, about 3cm in length, was made on the skin of the left submandibular region. The crown of the impacted tooth was exposed vertically from the lower border of the mandible. The tooth was removed carefully. The postoperative course was uneventful.
