What is the pattern of cancellous bone in the posterior maxilla?

• A. Very different, with tiny marrow spaces.
• B. Dense with no marrow spaces.
• C. Similar to anterior maxilla but with slightly larger marrow spaces.
• D. Coarse pattern like anterior mandible.

Answer: (C)

Cancellous bone in the maxilla is a network of trabeculae with marrow spaces, and the pattern in the posterior region resembles that of the anterior maxilla. The main regional difference is that the marrow spaces tend to be a bit larger in the posterior maxilla, reflecting regional variations in remodeling and vascularity. This is why the best description is that the posterior maxilla has a cancellous pattern similar to the anterior maxilla but with slightly larger marrow spaces.

The other descriptions don’t fit because cancellous bone by definition contains marrow spaces, so it isn’t “dense with no marrow spaces.” It isn’t a very different pattern from the anterior maxilla, nor does the posterior maxilla resemble the coarse pattern typical of the anterior mandible.