Nose, sinuses and orbit

Why this matters

A dental student will be told that the nose, the sinuses and the orbit belong to ENT and ophthalmology. The measurements say otherwise. When a prospective series took 134 consecutive patients with unilateral sinus disease and complete maxillary opacification on CT, 60 of them (45%) turned out to be odontogenic — and of those 60, 65.5% of the CT reports made no mention of dental pathology [R74].

The big picture

This is one continuous space with thin partitions. A maxillary molar apex sits under the floor of an air-filled box whose only natural exit is about 3 cm higher up its medial wall; that exit opens into a narrow shared corridor in the middle meatus that also drains the anterior ethmoid and the frontal sinus; the ethmoid's paper-thin lateral wall is the medial wall of the orbit; and the orbit opens backwards, through the inferior orbital fissure, into the same fossae that a posterior maxillary infection can reach…

The 15 cards in this lesson

1. 01One corridor: from a molar apex to the eye
2. 02The nose in section: vaults, boundaries, mucosa and the septum
3. 03The lateral wall: conchae, meatuses and what each one receives
4. 04Four drainage lines the textbooks get wrong
5. 05Two carotids feed one nose
6. 06Clinical alert — in the lesson
7. 07The nerves of the nose are the nerves of the upper teeth
8. 08The olfactory apparatus: measured, inferred, and simply repeated
9. 09The four paranasal sinuses side by side
10. 10The sinus floor and the roots: what the measurements say
11. 11Clinical alert — in the lesson
12. 12The orbit: seven bones, four walls and the doors infection uses
13. 13In front of the septum or behind it
14. 14Clinical alert — in the lesson
15. 15What to carry out of this lesson

You have got it when

You can build the nasal cavity from its walls and say what each meatus receives — and say which part of that map is constant and which part depends on where the uncinate process attaches. You can name the two carotid systems that supply the nose, the three consistent contributors to Little's area and the study that demonstrated them, and explain why correct first aid can fail.