hello everyone this is doctor O and in this video we are going to talk
about temporal mandibular disorders so what are temporal mandibular disorders and what
occurs with dislocation of the jaw also known as subluxation of the temporal mandibular joint
so temporal mandibular disorders is sort of a broad term that encompasses all inflammation
of the temporomandibular joint this can involve many different types of structures
such as the bony articular surfaces that can be affected in arthritis either
osteoarthritis or rheumatoid arthritis this can also affect the articular disk
inflammation can also present in the retro articular tissue you'll remember that this
is where the neural vasculature sits and it is also within the articular capsule one other
structure that could be affected but all can be are the muscles of mastication so with overuse
of these muscles or chronic spasms this can also view to this temporomandibular disorder
any changes in the bone or the cartilage or misaligned teeth can lead to changes in the
temporomandibular joint and this disorder typically someone with temporal mandibular
disorders will experience a reduced range of motion as there is less space for that
joint to move around or the structures that are moving it are fatigued or not quite functioning
as usual people also experience pain this can be directly around the TMJ but it can also radiate
to the ear or to generally the feelings around a headache with chewing or speech people will
also often have crepitus or clicking of the joint and what this is related to is likely
this disc and it has a bit of a delayed movement through sort of the change in the joint structure
and that clicking is something you can hear but it also would lead to dysfunction of the joint
now for a temporal mandibular joint dislocation or subluxation of the mandible what this looks
like is starting in a closed position we see the condyle or the condylar process of the
mandible sitting in the mandibular fossa of the temporal bone when someone is yawning or
taking a really big bite or potentially at the dentist office and getting their teeth cleaned
the condylar process of the mandible displaces anteriorly now this displacement anteriorly is
what we call a protraction and some level of it is absolutely normal in order to get our mounts
fully open we need to see some protraction however if the condylar process Pro tracks or displaces
anteriorly beyond this articular tubercle that we can see here that then is a dislocation
and now you see that it kind of law into place anteriorly here and it locks open so typically
someone with a dislocated jaw or TMJ you'll see will be stuck sort of in an open position
when this yawning or really opening the mouth wide is happening that lateral pterygoid is
contracting so remember the lateral pterygoid muscle will protract but it will also depress
the mandible so if there's excessive contraction of this muscle that can lead
to kind of the rocking forward of that past that articular tubercle to a dislocation you
and in terms of the supportive structures of the TMJ the lateral ligament that course is
sort of on this lateral side and reinforces the capsule on the lateral side is really important
in preventing posterior displacements as well as lateral and so it is very infrequent that
there is a posterior dislocation of the TMJ so as well as that lateral ligament
we also see the bony structures kind of prevent the displacement posterior lis
whereas anteriorly there's a little bit more space to displace forward so I'd like you to
answer the following question I want you to describe the actions from a closed position
to a dislocated position of the TMJ so go ahead and pause so you can write out these actions
you
when you're ready let's talk through what happens so the first action that needs to take place to
get us closer to that dislocated position is depression so we see depression of the mandible
we saw that we started out here in the mandibular fossa that condylar
process is very well situated in the mandibular fossa and here it
looks like it's moved anteriorly so what is that action called
so the action in the anterior-posterior plane here would be Pro traction
and as we see here protraction beyond this articular tubercle
and now we're in a dislocated position
so thank you so much for your attention in this video I look forward to seeing
you in the next one and always feel free to reach out with any questions you may have