The following case originated from upstate New York. The case was be posted from July 27 to August 16, 1998.  A summary of the responses is available here.
 

Clinical History

A 10 month-old girl presented with an expansile 1.5 cm firm mass of the left anterior maxilla. Radiographically, the tumor was lucent, primarily unilocular and exhibited expansile borders although a small erosion through the palate was indicated. Developing tooth buds noted on the contralateral side seemed to be caught up in this process.

The following are 8 representative microscopic fields (stained with H&e) of the tumoral mass. Clicking any small image will present a much larger version of the image in a separate browser window. After viewing an image in this separate window, you may close, hide, or minimize that window and return to this page.

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Fig. 2. Low power view demonstrates a solid lesion. (0.5 x)

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Fig. 3. Low power view reveals odontogenic epithelium with plexiform and follicular patterns.  The connective tissue stroma is highly cellular. (2.3 x)
 

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Fig. 4. This magnification discloses the presence of ameloblastic epithelium in a highly cellular stroma. (6.3 x)

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Fig. 5. This field shows a highly cellular and myxomatous stroma. Mitotic activity is observed. (40 x)

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Fig. 6. At least three mitotic figures are observed in this slide.  The upper right field shows a row of basal cells of the ameloblastic epithelium.  (40 x)

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Fig. 7. Island of ameloblastic epithelium showing mitotic activity. (40 x)

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Fig. 8. Ameloblastic epithelium with a follicular configuration and a mitotic figure in the "stellate-reticulum"-like area. (40 x)