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So this is an example of a retromolar trigon carcinoma.

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It's located posterior to the right maxillary tuberosity and anterior to the

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anterior portion of the ramus.

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So this is the example here of the retromolar trigon carcinoma.

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Now one thing about this retromolar trigone carcinoma is that what I want

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you to do is look at the left side.

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See how this cortex here of the ramus of the mandible is intact.

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And look at the signal within the ramus of the left mandible on the left hand

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side, on the right hand side,

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the anterior portion of the ramus of the mandible that's eroded.

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And there's abnormal enhancement here involving the marrow.

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So this is an example of a retromolar trigone that also extended posteriorly to

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erode the anterior ramus of the mandible.

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So one thing I've noticed about retromolar trigone is that they tend to be one

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of the most under staged tumors.

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And that is if you look at in the retromolar trigone,

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if you've ever looked in someone's mouth, it's very,

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very hard to peer and look around that last tooth.

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So the surgeons can see this component of the retromolar trigone tumor,

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but they can't see that deep component.

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And because of the proximity of the rec, the um,

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ramus of the mandible to the maxillary tuberosity,

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if you have a three centimeter lesion in the oral tongue,

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well it's just gonna kind of burrow its way into the tongue.

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But if you put that same three centimeter lesion located right here,

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notice how it's gonna completely abut and grow into the bone.

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And this bone erosion is oftentimes clinically occult.

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So I strongly recommend, um,

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getting both CT and MR in patients with retromolar trigone

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carcinomas because of the early likelihood of tumor

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spread into the anterior portion of the ramus of the mandible.

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So let me stop there and do you have any questions on that?

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So this is the part right here is a tonsil.

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So this is the anterior tonsor pillar. This is the palatine tonsil,

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and this is the posterior tonsor pillar.

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This muscle right here is the superior constrictor muscle,

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and this is the bator muscle.

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So where the superior constrictor muscle interdigitates with the bator muscle.

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That tendon right there is the tego mandibular.

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The teeth are the central incisor lateral incisor, canine first,

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premolar second premolar, first molar, second molar third molar.

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This space behind the third molar is the retromolar trigone.

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So here is the ramus of the mandible.

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So if you have tumors that are involved in the retromolar trigone,

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they can grow posteriorly.

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They can jump here along the superior constrictor muscle.

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They can involve the tego mandibular and they can extend and then they

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can involve the bone. Once tumors get on this region,

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they can grow posteriorly along the superior constrictor muscle.

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They can grow anteriorly along the vaccinator muscle or

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They can jump on the tego mandibular ra and extend all the way up into the

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superior skull base. So in this particular case,

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this retromolar Trigon carcinoma extended into the region

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of the Tego mandibular ra.

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And this is associated with erosion here of the anterior portion of the

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mandible.

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So this is a nice example here of the Retromolar Trigo carcinoma.

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And in this case, look at the left hand side.

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We can see the superior constrictor muscle here.

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And notice on the right hand side,

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we can see this tumor growing along the superior constrictor muscle.