The floor of the nasal cavity that is visible on radiographs is actually the junction of the floor and lateral wall or vomer. On intraoral radiographs this will appear as a single radiopaque straight line superior to the maxillary teeth. It is visible on any periapical radiograph (anterior and posterior). On a pantomograph it may appear as a single radiopaque line or up to three radiopaque lines may be visible. The appearance of three lines is created by the two lateral walls (right and left) meeting the floor and the vomer meeting the floor. Below are examples on periapical radiographs and a pantomograph.
Premolar periapical radiograph showing a straight radiopaque line near the superior aspect of the image (floor of the nasal cavity).
If you have any radiographic examples, questions or comments about the floor of the nasal cavity, please leave them below. Thanks and enjoy!