Presentation
Hard lump in the floor of the mouth.

Photo of a mandibular torus (as viewed in an intraoral mirror)
Image credit: D Rosenbach. See case discussion for full attribution.
Case Discussion
Image attribution
Author: D Rosenbach
Original file: https://en.wikipedia.org/wiki/File:Torus_cropped.jpg
License:
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Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.
Modifications: square crop