the temporal and infra temporal fossa the inter temporal fossa has the following borders and contents yellow arrow shows where the temporal fossa is and it's called the inferred temporal fossa gates we move in an inferior direction and go below that zygomatic arch and deep to the ramus of the mandible that's when we're inside that infra temporal fossa we now take a look at an inferior view of the skull and we're now in this infer temporal fossa that dotted green area is showing the borders and what are the borders of the infra temporal fossa well first this is the area that's deep to the zygomatic arch posterior to the maxilla anterior to the mastoid process of the temporal bone and lateral to the pterygoid plate of the sphenoid bone there we have the borders of the info temporal fossa what are the contents of the infra temporal fossa they include the following there's the foramen ovale that transmits the mandibular branch of the trigeminal nerve vn3 and there's the mandibular nerve entering the inferred temporal fossa so if you remember this picture from previous tutorials there is where the framing of valley is located and that's where v3 gets into the info temporal fossa next is the foramen spinosum that transmits the middle meningeal artery well there's the framing spinosum in that middle meningeal artery and so remember this picture there's a middle meningeal artery that supplies the dura mater and that is how the middle meningeal artery gets from in for temporal fossa to the scalp prior to the dura mater pardon me next is the infraorbital fissure that transmits cranial nerve v to the maxillary nerve and there we've got that infraorbital fissure then here we've got in green showing the v 2 and that's the infraorbital fissure where the V 2 is going to transmit to go from in for temporal fossa to the maxillary region next is some opening called the petro tympanic fissure that's what trans it's the chorda tympani nerve as evidenced there's just medial and posterior to the mandibular fossa so remember this picture that shows the in blue that chorda tympani nerve as it joins a lingual nerve well that's how the chorda tympani nerve gets into the info temporal fossa to bind to the lingual nerve and finally the mandibular fossa is a concave surface it serves as an articulation for the temporal mandibular joint and there we have it so those are the borders and contents now let's do some other things for the info temporal fossa for example let's talk about the temporomandibular joint so the temporal mandibular joint also known as the TMJ has the following components there's the mandibular fossa remember in green arrow there then there's an articular disk in this articular disc is fibrocartilage that resides between the mandibular fossa and the mandibular condyle that's going to articulate with the mandibular fossa to make a synovial by conjul or hinge joint then the joint capsule is a is the extension of the periosteum from the mandibular condyle that wraps around and goes to the mandibular fossa so there we have the components of the temporomandibular joint let's talk now about the muscles of mastication that act on the temporomandibular joint so first is our masseter muscle that arises from the zygomatic arch and then courses down to attach to the ramus of the mandible and it's what is the action of this muscle is to elevate the mandible with power at the TMJ and it's innervated by cranial nerve v3 the mandibular branch of the trigeminal nerve next is our temporalis muscle it arises from the temporal fossa and courses down to attach to the coronoid process of the mandible and notice it goes deep to the zygomatic arch the action of this muscle is also to elevate the mandible with power as in mastication chewing and in this muscles also innovated by creme Euler v3 now the medial pterygoid muscles and muscle it attaches its deep to the ramus of the mandible and it courses from the ramus of the mandible to the pterygoid plate and the action of this muscle is a side-to-side movement of the mandible as in chewing and this muscle is also innervated by cranial nerve v3 the lateral pterygoid muscle arises from the coronoid the condyloid process of the mandible and courses to the pterygoid plate and this muscle is going to help depress the mandible and move the mandible protract the mandible forward and the lateral pterygoid is innervated by granular v3 the mandibular branch of the trigeminal nerve so here we have the temporal mandibular joint again now the condylar head of the mandible is seated in the mandibular fossa the articular disk is situated between the condyle and the fossa so there is mandibular fossa there's articular disc which is between the mandibular fossa and that mandibular condyle and there we have the lateral pterygoid muscle so the lateral pterygoid muscle contracts it pulls the mandibular condyle in articular discs inferiorly and anteriorly and this is how we can get the jawed open up so wide so the contraction of the lateral pterygoid muscle pulls both the condylar head in articular discs anterior inferior to depress the mandible in this fashion all right now the muscles of mastication what branchial arch does the mandible mandible and associated muscle derives from it's derived from the first Branca large that meckel's cartilage and the mandible and all these muscles of form around it muscles of mastication and so forth so therefore the common innervation is the first branchial arch that gives rise to muscles of mastication is the trigeminal are specifically granular v - 3 all right also in the m4 temporal fossa are now nerves so nerves of the m4 temporal fossa so we have the info alveolar nerve in the mental nerve and the lingual nerve let's focus on the first two there we have the foramen ovale that transmits the mandibular nerve cannula v3 into the inferred temporal fossa and gives rise to the inferior alveolar nerve branch of v3 which goes to the TI mandibular teeth and then exits via this mental foramen to give rise to innovating the skin of the chin and lower lip in this picture there is the infallible alveolar nerve but it's been cut we can see that mental nerve exiting the mental foramen and then there's our lingual nerve as well and the lingual nerve in yellow there is let yellow is going to bring general sensation from the front of the tongue but also has contributions from cranial nerve seven and so they're in greening to do that a couple of times you see in green right there there is our quarter tympani nerve it's a branch of cranial nerve seven here we now have cranial nerve seven specifically talking about the chorda tympani branch so there's the court at mpany nerve and in green there it is as it enters the infant temporal fossa via that petrol tympanic fissure and once inside the infant temporal fossa the quarter tympani nerve is going to innervate our sublingual and submandibular salivary glands as well as bring special sensation from the anterior two-thirds of the tongue or taste and so how is that nerve going to get to house according to empathy when you get to its structure well here we've got cranial nerve II - 3 so the chorda tympani nerve is going to hitchhike on cranial nerve II - 3 to get from the tongue and from the salivary glands in that infer temporal fossa so here we have it again there is our lingual nerve from v3 and there's the quarter tympanic branch from 7:00 in the in four temporal fossa