hi let's talk about the oral cavity and the sublingual space so the oral cavity can be
divided into two major regions the oral vestibule which is everything that is superficial to the
gingiva and the dental arches so basically everything between the the labial surfaces
and the buccal surfaces and the the teeth and the gingiva is the oral vestibule and then deep
to the gingiva and the dental arches is the oral cavity proper in that oral cavity proper is going
to run from the roof of the mouth which we can't see here down to the mylohyoid muscles anything
below the floor of the oral cavity here is going to be the sublingual space which is
a part of the oral cavity proper so that's it's kind of an important thing to to wrap your mind
around that the oral cavity proper is everything from the roof of the mouth down to the mylohyoid
muscles and those mylohyoid muscles are going to be the floor of the oral cavity proper but
dividing the oral cavity from the sublingual space which is part of the oral cavity proper
is going to be that that oral mucosa at the that's contiguous with the ventral surface of
the tongue so here we have a very similar view this time cadaveric photograph and the mucosa
of the floor of the the mouth there has been incised and removed and we're able to see some
features here so laterally here I can see there's one sublingual gland there's another sublingual
gland those when enveloped by mucosa would be the sublingual folds I can also see distal portions
of the submandibular or Wharton's duct that would be heading out towards the current goal
there to excrete into the oral cavity proper and just flanking the genial glosses which is
this muscle coming from the posterior portion of the mental portion of the mandible up into
the tongue I can see lingual nerves which are branches of v3 so that that mandibular division
of the trigeminal nerve here is a lateral view of the sublingual space so here is the tongue
the mucosa has been removed from the side of the tongue so we can see some of the the musculature
here is just a little bit of the mandible most of it has been carved away for reference and
we have a few structures here that are going to be very very obvious to us the first being the
sublingual gland here so the sublingual gland is going to occupy quite a large portion of the
the sublingual space flanking that genioglossus muscle which we can see there we can also see
one of its colleagues the submandibular gland the submandibular gland is going to traverse
two spaces so the submandibular space is going to hold the superficial portion of the submandibular
gland which we can see there and then wrapping around the mandible we can see the deep love
of the submandibular gland we can also see let's see it's a little challenging but we can see the
duct you can see Wharton's duct moving across and then just snuggling the sublingual gland
out towards the the coronal distally we can also see and this would be coming from the
the infra temporal fossa the lingual nerve coming down and then it's cradling the duct
here so this is Wharton's duct I'm just gonna color this in and so there's the remainder of
the lingual nerve wrapping around the duct so this is a v3 branch coming down and associated
with that lingual nerve is the submandibular ganglion that submandibular ganglion is getting
its preganglionic parasympathetic fibers from chorda tympani which is facial and then those
fibers jump right back on and then they can serve the submandibular gland they can serve this up
lingual gland and those chorda tympani fibers can continue on with the lingual nerve to serve
the anterior 2/3 of the tongue for taste what else can we see here oh this is an interesting
thing so descending down here laterally and cutting across is the hypoglossal nerve
so that's going lateral to our external carotid artery
coming across in so hypoglossal nerve is going to be an important offense to the tongue muscles and
it has an accompanying vein so this is a vena comitans of the hypoglossal nerve the remainder
of that vein has been removed here and let's see if we can see any of the lingual artery
here yes well let's let's start where the the lingual artery would begin from the external
carotid and we can see that originating here from the external carotid artery and
heading into the sublingual space I imagine that in this next image we'll get a little bit better
of a look at it let's start there so this might be a little out of water so here's our external
carotid artery and I'll just follow this lingual artery up continue and then here it's diving deep
to the Hyoglossus muscle running between the hyoid bone and into the tongue and then it emerges from
the anterior margin the high up glasses to serve the sublingual space and there will be
deep branches that are actually going into the tongue here so in this particular image we've
removed the any aspect of the lateral mandible we still have some of the mandible out towards
the the mental region there now we can see here is the superior border of the thyroid cartilage
their hyoid bone is going to be approximately there and we can get a view of the lingual nerve
although this has been displaced superiorly is the lingual nerve coming around the the submandibular
duct has been removed because we've removed the submandibular gland we get a really nice view
of the lingual nerve there and we can see the hypoglossal nerve here cutting across coming
over and one of the things that I wanted to point out to you is that in this posterior portion of
the the sublingual space the hyoglossus muscle is going to form a partition and so lateral to
that partition we find things like the lingual nerve and the hypoglossal nerve and then we'll
also have the the submandibular duct and then deep or medial to that partition we'll have the
the lingual artery so nerves lateral arteries deep the only little bit of vasculature that
will also find lateral is the the vena comitans of the hypoglossal nerve as it as it traverses
that space along with the hypoglossal nerve and now we'll we'll take a few of the lateral or a
lateral view of the submandibular space we can see just one of the the anterior borders of that
so this is the anterior belly of the digastric muscle the posterior belly of the digastric muscle
has been rotated away but we get a good view of the superficial lobe of the submandibular gland
that's in that space we can also see 12 to the hypoglossal nerve traversing down and in this
case it's going deep to the mylohyoid muscle so here's mylohyoid mylohyoid muscle is running from
the mylohyoid line of the mandible across to the midline to meet its counterpart so this is
the floor of the oral cavity proper we can also see in this particular donor that the lingual
artery which is originating there and the facial artery which is originating there are coming from
a common trunk that happens sometime but here is the lingual artery moving in it's going deep
deep and we can see that there's a little bit of the hyoglossus muscle there that's separating the
lingual artery from the hypoglossal nerve and its accompanying vein which we can see there so
we've we've talked a little bit about the oral cavity and a lot about the sublingual space and
the submandibular space one final thing that I'd like to to leave you on before I sign off
in this video is that the sublingual space and the submandibular space can communicate with one
another when you go to that posterior border of mylohyoid those two spaces are contiguous with
one another and as we move posterior to those two spaces we have the lateral pharyngeal space and
so both the sublingual space and the submandibular space can communicate with that lateral pharyngeal
space with the retropharyngeal space so any sort of infection cellulitis etc that enters
into the the sublingual space or originates from that submandibular space can then move
through the lateral and retropharyngeal spaces and that's going to encircle the the pharynx
the aerodigestive pathway and so this is the the basis for Ludwig's angina which is an emergent
situation where it is a severe compromise of of the airway thank you very much for your time