Hi everyone, I'm Prateek and in this video we're going to be looking at the anatomy of panoramic
films or OPTs, DPTs or OPGs. If you haven't done so already please make sure to check out my book
Single Best Answer Questions for Dentistry. For anyone sitting dental examinations this is a
key revision resource with over 280 single best answer questions - all the links are in
the description. OPTs can be quite difficult to interpret if you're not used to looking at them
but hopefully in this video I'll go through some of the key anatomical landmarks on OPTs to help
you become more confident with interpreting them. So first let's look at the mandible. Here we can
see the mandibular condyle so this will be seen as a rounded radiopaque area located within
a glenoid fossa towards the lateral aspect of the panoramic film. The glenoid fossa remember is that
concave area that we have in the zygomatic process of the temporal bone and it forms part of the
temporomandibular joint. The coronoid process can be seen more medial to the condyle as a
radiopaque, triangular area typically overlying the maxillary tuberosity and maybe some of the sinus.
If we're looking at the mandibular condyle and the glenoid fossa just in front of this you can
see the articular eminence and remember how again this is a key component of the temporomandibular
joint. If we follow down from the mandibular condyle and the coronoid process, we follow on to the ramus
of the mandible. This then joins onto the body of the mandible and the location that these two
come together is the angle of the mandible. Within this area, we'll be able to see a radiolucent
canal that has two parallel radiopaque lines and this is the inferior alveolar canal where you
have the inferior alveolar nerve traveling through. This radiolucent band will travel from the middle
of the ramus through the body of the mandible and then will ultimately reach a radiolucent, round
or ovoid area roughly around the apex of the lower four and five region and this is where we have the
mental foramen where the mental nerve will exit the mandible. We also have the lower border of the
mandible which is a thick radiopaque band that we can see here. Next let's look at the maxilla.
So we have the maxillary sinus either side and this is seen as a large radiolucent
area above the maxillary dentition. Surrounding this radiolucent area we have the walls, or the
borders, of the maxillary sinuses and these are seen as thin radiopaque lines. Often these lines
can come very close to the maxillary teeth hence the reason that we warn patients of the risk of
oro-antral communication. On an OPT, if we think of how the imaging is done, the machine rotates around
the patient and therefore you have to consider the panoramic film as the patient's face flattened out.
So when we're looking at the maxillary sinus walls on a panoramic film, we are seeing the posterior
wall and we're seeing the floor of the maxillary sinus. These are key areas to look at if we're
considering identifying any sinister pathology - if these lines are missing, it's of significant concern.
We can then also see the zygomatic process of the maxilla or the malar buttress
and this usually comes down as a U, V or J shaped radiopaque area usually around the
first or second maxillary molars and this is why sometimes it can be difficult to take these teeth
out because the bone is usually quite dense in this region. If we then look at the nasal cavity,
the borders of the nasal cavity can be seen as radiopaque lines medial to the maxillary
sinus. We can also see a soft tissue within the nasal cavity this includes the nasal septum
which is a radiopaque area at the centre of the panoramic film as well as potentially the inferior
nasal turbinate, which is seen as a round or a curved radiopaque mass within the nasal cavity. You
can see the floor of the nasal cavity as well, or the hard palate, and this will be present as a thin
radiopaque line and it may again be superimposed over other structures such as the maxillary sinus
or the maxillary teeth. If we then move to other structures of the midface. We can often see
the orbital rim which is a thick, semi-circular radiopaque line superior to the maxillary sinuses.
Additionally, lateral to the maxillary sinuses we can often see the pterygomaxillary fissure which
is an inverse teardrop shape of radiolucency surrounded by a very thin radiopaque line.
Next we may also see the zygomatic bone. So we've already spoken about the zygomatic process of the
maxilla so if we look at this area and then we follow it backwards we can see the zygomatic bone
and going onto the zygomatic arch. So we have this radiopaque area distal from the zygomatic process
and with the path that is taking it will usually be superimposed of the maxillary tuberosity and
the pterygomaxillary fissure. Other little bits of anatomy that you may notice on an OPT. You may see
the external auditory meatus as a round or ovoid radiolucent area lateral to the glenoid fossa
or the condyles of the mandible. You may also see the soft tissue of the earlobe and this is again
seen as a radiopaque area roughly superimposed or around the areas of the ramus of the mandible.
The cervical spine is also seen on a panoramic film. You will typically have superimposition
of the cervical spine through the centre of the film and this can often make interpreting anterior
anatomy quite difficult but also depending on the positioning of the patient, you may also see
the cervical spine on the lateral aspects of the panoramic film. Additionally, adjacent to
the cervical spine if it is present laterally, you may see the styloid process. The styloid process
may be insignificant in most patients, however in some patients an elongated styloid process
can be an indication of conditions such as Eagle Syndrome. Next if we look inferior or just along
the lower part of the mandible we may see the hyoid bone as another radiopaque area. This
can be superimposed over the mandible. So we've got the soft palate as well. The soft palate can
be seen as a radiopaque mask that is found next to the hard palate however it is less radiodense
compared to surrounding boney structures because there is no bone present within the soft palate.
We can also consider the air spaces. So we have the nasopharynx which is found as a radiolucent area
coming off from the nasal cavity. Below this we have the oropharynx which is a radiolucent area
that is attached to the airspace in the mouth and then below this we have the hypopharynx. From the
oropharynx if we follow this into the mouth in some patients who haven't put their tongue to the
roof of the mouth during the panoramic film we may see an obvious shadowing or darkening within the
oral cavity that is indicative of the airspace that is present there. So hopefully this has
covered most of the important anatomy in an OPT and now you'll feel more confident interpreting
this form of imaging. My recommendation in this video is the BrushDJ app, which is an app created
by dentist Ben Underwood in order to help patients with their oral hygiene. If you did find this
video useful, please make sure to like, comment and subscribe - until the next video, take care!