Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 9 On the Twelve Bones of the Upper Maxilla, Including the Bones of the Nose

Third maxillary bone

The third bone [lamina orbitalis ossis ethmoidalis] of the upper maxilla (Q in figure 1), like the second, appears thin and translucent like a scale. When it is broken, it is seen to abound with large, air-filled cavities [cellulae ethmoidales]. It is nearly quadrangular, located in the inner side of the eye socket. On top (from T to V in fig. 1), it ends at the suture [sutura fronto-ethmoidalis] common to the frontal bone and the upper maxilla. Anteriorly (from V to c in fig. 1), its suture [sutura ethmoidolacrimalis] is common to the second maxillary bone; posteriorly (from T to d in fig. 1), its suture [sutura spheno-ethmoidalis] is common to the cuneiform bone [os sphenoidale]. In its lower portion (from c to d in fig. 1), it has a suture [sutura ethmoidomaxillaris] common to the fourth maxillary bone. This third bone is therefore connected to four bones: the frontal bone above, the second maxillary bone [os lacrimale] in front, the cuneiform [os sphenoidale] behind, the fourth maxillary [maxilla] below. On the inside, where it faces the nasal cavity [cavum nasi], it meets an irregular construction of bones [labyrinthus ethmoidalis] in the top of the nostrils.



Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 9 On the Twelve Bones of the Upper Maxilla, Including the Bones of the Nose