COM July 2007

This is a 15-year-old white female who presented with a history of increasing swelling without pain in the left mandible. Her mother noted the swelling and took her to the family dentist for a clinical evaluation where a periapical radiograph was taken. The dentist then referred this patient to Dr. Grace who took a panoramic radiograph (Fig 1). This radiograph revealed a large scalloped radiolucency in the left posterior mandible extending into the ramus. There is a hit of multilocular appearance of the radiograph. Also identified were multiple missing teeth. There was no impacted third molar in the site. She had no soft tissue swelling or pain at the site and no parasthesia.

Figure 1. Panoramic view at first presentation demonstrating large radiolucency with scalloped border and a hint of multilocular appearance extending high into the ramus.  Notice the missing teeth and the absence of teeth # 17 and 18.

The patient is otherwise healthy with no significant medical or family history.

At presentation, a swelling in the left mandible was identified. The swelling was not painful. The panoramic radiograph showed a large radiolucency with scalloped border and a hint of multilocualrity. The swelling started at the left posterior mandible and extended into the ramus. The radiograph revealed multiple missing teeth with no impacted third molar tooth in the site. There was no evidence of soft tissue swelling or parasthesia. The CT scan revealed a radiolucent lesion with no mass or evidence of tumor.

Figure 1. Panoramic view at first presentation demonstrating large radiolucency with scalloped border and a hint of multilocular appearance extending high into the ramus. Notice the missing teeth and the absence of teeth # 17 and 18.

Histologic examination revealed multiple pieces of hard and soft tissue made up of ribbons of loose and vascular connective tissue and early bone formation (Fig 2). In one area, a piece of loose connective tissue with cholesterol clefts and multinucleated foreign body type giant cells were present (Fig 3). The specimen also contained small aggregates of extravasated erythrocytes (Fig 4) which were interpreted to be surgically induced.

Figure 2. Low power (x100) histology shows small fragments of viable early bone formation and loose and vascular fibrous connective tissue.

Figure 3. Low power (x100) histology shows a cluster of cholesterol granuloma made up of cholesterol cleft surrounded by multinucleated foreign body type giant cells.

Figure 4. Low power (x100) histology shows clusters of extravasated erythrocytes and bone fragments with viable osteocytes.