This is a tutorial on the facial skeleton. It’s the second tutorial on the skull. Hopefully, you’ve watched the first tutorial which was on the bones of the upper skull, so the bones which house the brain and which I refer to as the calvaria, so all these bones here. This tutorial is on the rest of the skull, the lower and anterior part, which is called the facial skeleton or the viscerocranium.
If you just remember from the last tutorial, the skull consists of the upper part and the lower part. The mandible isn’t actually considered part of the cranium. I’ll do a separate a very, very short tutorial on the mandible, but this is just focusing on the facial skeleton.
There are several bones which make up the facial skeleton. You’ve got the nasal bones, the maxilla, the zygomatic bone, the lacrimal bone on either side. Then you’ve got the vomer, the palatine bone and the inferior nasal conchae. I’m going to just talk you through those bones and hopefully, you’ll have a good understanding of those by the time I finish with this tutorial.
Just loads of things in anatomy, there’s a mnemonic for remembering these bones and that’s ‘Virgil cannot make my pet zebra laugh.” That’s vomer, conchae, nasal bone, maxilla, mandible (which isn’t technically part of the facial skeleton, but anyway, it’s included in this mnemonic), palatine, zygomatic and lacrimal. I’ll just talk you through those.
You’ve got these nasal bones up here, which articulate with the frontal bone and the maxilla on either side. And where they meet the frontal bone and where they join together, this point here is known as the nasion, which I’ve talked about in my tutorial on sutures. Those are the nasal bones.
And here, you’ve got this bone here, the maxilla. This, as you can see, makes up the medial part of the orbit as you can see here. It’s got a few processes. First, this is just something that basically just sticks out. This process is called the frontal process because it articulates with the frontal bone. And then you’ve got this process here, which is the zygomatic process of the maxilla because it articulates with the zygomatic bone laterally. And then this here is called the alveolar process because it articulates with the teeth. You’ve got the alveolar process, the zygomatic process and the frontal process.
And then you can probably see this little hole here. You’ve got quite a lot of these tiny, little holes, these openings on the skull. They are foramen. Any little hole, a natural opening in the body, which allows structures to pass through is known as a ‘foramen’ and the plural of ‘foramen’ is ‘foramina’. You’ve got a lot of these on the skull because I think I’ll do a separate tutorial on them because you’ve got so many and they’re quite important to know about and in particular, know what structures pass through them.
This one here is the infraorbital foramen and you’ve also got the supraorbital foramen, which is part of the frontal bone. You can’t quite just about make it out. It’s more of a notch. I think it’s called the supraorbital notch. They just allow the infraorbital and supraorbital vessels to pass through and nerves to pass through. That’s the maxilla bone.
Next, just moving around laterally, you’ve got the zygomatic bone. This bone is the bone which is referred to as the cheek bone. You can feel it on yourself. It’s the bone here which articulates with the temporal bone here, the frontal bone and the maxilla.
Again, you can see the lower lateral orbit is made up of the zygomatic bone. And again, you’ve got a little foramen here and I’ll talk about these in another tutorial.
This big hole here is called the piriform aperture. That’s obviously where the nose sits. If I just show you the nasal cartilage, that’s where the nose sits. It opens to all the passageways of the nose. It’s quite important to just look at some of the structures through this piriform aperture.
You can see this structure here. I don’t think I talked about it in my last tutorial, but this is the perpendicular plate of the ethmoid bone. It’s called the ‘perpendicular plate’ because it drops perpendicularly down from the ethmoid bone.
And then these structures that you can see from this anterior view on either side are the concha or conchae in plural. These are bony structures that make up the passageways of the nose. This is the middle conchae. You can’t see the superior concha from this view. The middle nasal concha makes up a part of the upper cranium. They’re part of the calvaria and not the facial skeleton.
This structure here is the inferior nasal concha. If we just zoom in, you can see that. This long bone that extends posteriorly, this is the inferior nasal concha and it’s part of the maxilla bone. You can see this is the maxilla bone and the inferior nasal concha is part of that. The inferior nasal concha is another bone of the viscerocranium.
It’s like a little shelf that allows the passage of air into the nasal cavity and down into the pharynx and ultimately, into the trachea and lungs. You can see this little concave indentation, that’s where the passageways for air run. The passageway is known as the meatus and that extends into the posterior nasal cavity.
There’s quite a lot to talk about with the conchae and the meatus and all the structures of the nose, but I think I’ll do that as a separate tutorial on the actual nose.
What you want to know here is that the inferior nasal concha is part of the maxilla and is a bone of the facial skeleton and just that this is the perpendicular plate of the ethmoid bone and these structures are middle nasal concha. You’ve got superior nasal concha, which you can’t see here and they’re part of the upper cranium.
Next, we’ve got the little lacrimal bones. These are the tiny bones that lie here. Anteriorly, you’ve got the maxilla and then you’ve got this sphenoid bone, the zygomatic bone and the frontal bone. you can just see if I zoom in a bit more, this is the lacrimal bone here, this little bone. You’ve got it on both sides obviously. these little paired lacrimal bones.
I’ve talked about the nasal bones, the maxilla, the zygomatic bones, the bones that you can see through the piriform aperture, the inferior nasal concha on both sides. I didn’t talk about this bone here, which is the vomer. I’ll just come on to show you that now.
You can see the vomer through here, but I think I’ll rotate around to a different view and show you the other bone, the palatine bone. I’ll just switch the view around there.
If we look inferiorly, I’m rotating the skull around so we’re looking at it from the bottom of the skull now. if we’ll just see what I did, I just rotated the skull so it’s tilted backwards. And now if we just keep around this maxilla bone and you can see as you rotate it around, we’re just looking at the underside of the maxilla, just there.
Here, this whole structure here is the hard palate. You can feel this in yourself. If you put your tongue to the roof of your mouth, you can feel your hard palate. And if you moved your tongue posteriorly, you can feel the soft palate, which is made up of soft structures. This whole structure is the hard palate and it consists of two bones, this anterior part here is made up of the maxilla and then this posterior part is the palatine bone and this is another bone of the facial skeleton. you’ve got left and right palatine bones. And anteriorly, you’ve got the maxilla. But this whole structure is the hard palate. The hard palate consists of the maxilla and palatine bones.
If we just remember, I was talking about the vomer, if I rotate it around, you can see – oh, what have I done? Let’s get that view back. if we just zoom in a bit, you can see something that’s extending backwards from the palatine bone. This is the vomer which you saw through the piriform aperture. This bone here is the vomer.
I think a good way to sort of visualize or understand this bone is by showing, coming from behind and having a look. Just looking at the vomer from here, you can see I’m just going to rotate it around and we’re going to have a look posteriorly. you can see this is the vomer here. And then you can see the palatine bones and the maxilla, which makes up the hard palate, this whole structure here. the posterior part is the palatine bone. And then you can see how the vomer sits on top of the palatine bone and it extends backwards like that.
Just rotating around again so you can see the vomer here. I’m rotating completely to posterior view. You can see how it separates these two oval shaped openings. These are known as the posterior nasal apertures or the choanae. This is the opening into the nasopharynx from the nasal cavity. that’s the vomer. You can see it here sitting on the palatine bones and extending all the way around to here.
just to recap what I’ve gone through, the bones of the facial skeleton, you’ve got the nasal bones, the maxilla, the zygomatic bones on either side and then you’ve got the bones which you can see through the piriform aperture, the inferior nasal conchae (which are part of the maxilla), the vomer and the palatine bones. And then medially, making up the medial wall of the orbit, you’ve got the lacrimal bones on either side.
You can remember these bones of the lower skull with the mnemonic ‘Virgil can not make my pet Zebra laugh.” That’s vomer, conchae, nasal, and maxilla, mandible, palatine, zygomatic and lacrimal. But remember that the mandible isn’t actually part of the facial skeleton. It’s just included in the mnemonic to help you remember bones of the lower skull.
That’s covered all the bones of the skull. Hopefully, having a good look at those has helped you remember them.