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Mandibular Nerve
In neuroanatomy, the mandibular nerve (V) is the largest of the three divisions of the trigeminal nerve, the fifth cranial nerve (CN V). Unlike the other divisions of the trigeminal nerve ( ophthalmic nerve, maxillary nerve) which contain only afferent fibers, the mandibular nerve contains both afferent and efferent fibers. These nerve fibers innervate structures of the lower jaw and face, such as the tongue, lower lip, and chin. The mandibular nerve also innervates the muscles of mastication. Structure The large sensory root emerges from the lateral part of the trigeminal ganglion and exits the cranial cavity through the foramen ovale. Portio minor, the small motor root of the trigeminal nerve, passes under the trigeminal ganglion and through the foramen ovale to unite with the sensory root just outside the skull. The mandibular nerve immediately passes between tensor veli palatini, which is medial, and lateral pterygoid, which is lateral, and gives off a meningeal br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandibular Division
In neuroanatomy, the mandibular nerve (V) is the largest of the three divisions of the trigeminal nerve, the fifth cranial nerve (CN V). Unlike the other divisions of the trigeminal nerve (ophthalmic nerve, maxillary nerve) which contain only afferent fibers, the mandibular nerve contains both afferent and efferent fibers. These nerve fibers innervate structures of the lower jaw and face, such as the tongue, lower lip, and chin. The mandibular nerve also innervates the muscles of mastication. Structure The large sensory root emerges from the lateral part of the trigeminal ganglion and exits the cranial cavity through the foramen ovale. Portio minor, the small motor root of the trigeminal nerve, passes under the trigeminal ganglion and through the foramen ovale to unite with the sensory root just outside the skull. The mandibular nerve immediately passes between tensor veli palatini, which is medial, and lateral pterygoid, which is lateral, and gives off a meningeal branch (ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foramen Ovale (skull)
The foramen ovale (Latin: oval window) is a hole in the posterior part of the sphenoid bone, posterolateral to the foramen rotundum. It is one of the larger of the several holes (the foramina) in the skull. It transmits the mandibular nerve, a branch of the trigeminal nerve. Structure The foramen ovale is an opening in the greater wing of the sphenoid bone. The foramen ovale is one of two cranial foramina in the greater wing, the other being the foramen spinosum. The foramen ovale is posterolateral to the foramen rotundum and anteromedial to the foramen spinosum. Posterior and medial to the foramen is the opening for the carotid canal. Variation Similar to other foramina, the foramen ovale differs in shape and size throughout the natural life. The earliest perfect ring-shaped formation of the foramen ovale was observed in the 7th fetal month and the latest in 3 years after birth, in a study using over 350 skulls.In a study conducted on 100 skulls, the foramen ovale ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tensor Tympani
The tensor tympani is a muscle within the middle ear, located in the bony canal above the bony part of the auditory tube, and connects to the malleus bone. Its role is to dampen loud sounds, such as those produced from chewing, shouting, or thunder. Because its reaction time is not fast enough, the muscle cannot protect against hearing damage caused by sudden loud sounds, like explosions or gunshots. Structure The tensor tympani is a muscle that is present in the middle ear. It arises from the cartilaginous part of the auditory tube, and the adjacent great wing of the sphenoid. It then passes through its own canal, and ends in the tympanic cavity as a slim tendon that connects to the handle of the malleus. The tendon makes a sharp bend around the ''processus cochleariformis'', part of the wall of its cavity, before it joins with the malleus. The tensor tympani receives blood from the middle meningeal artery via the superior tympanic branch. It is one of two muscles in the tymp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medial Pterygoid Muscle
The medial pterygoid muscle (or internal pterygoid muscle), is a thick, quadrilateral muscle of the face. It is supplied by the mandibular branch of the trigeminal nerve (V). It is important in mastication (chewing). Structure The medial pterygoid muscle consists of two heads. The bulk of the muscle arises as a deep head from just above the medial surface of the lateral pterygoid plate. The smaller, superficial head originates from the maxillary tuberosity and the pyramidal process of the palatine bone. Its fibers pass downward, lateral, and posterior, and are inserted, by a strong tendinous lamina, into the lower and back part of the medial surface of the ramus and angle of the mandible, as high as the mandibular foramen. The insertion joins the masseter muscle to form a common tendinous sling which allows the medial pterygoid and masseter to be powerful elevators of the jaw. Nerve supply The medial pterygoid muscle is supplied by the medial pterygoid nerve, a branch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior Belly Of Digastric
The digastric muscle (also digastricus) (named ''digastric'' as it has two 'bellies') is a small muscle located under the jaw. The term "digastric muscle" refers to this specific muscle. However, other muscles that have two separate muscle bellies include the suspensory muscle of duodenum, omohyoid, occipitofrontalis. It lies below the body of the mandible, and extends, in a curved form, from the mastoid notch to the mandibular symphysis. It belongs to the suprahyoid muscles group. A broad aponeurotic layer is given off from the tendon of the digastric muscle on either side, to be attached to the body and greater cornu of the hyoid bone; this is termed the suprahyoid aponeurosis. Structure The digastricus (digastric muscle) consists of two muscular bellies united by an intermediate rounded tendon. The two bellies of the digastric muscle have different embryological origins, and are supplied by different cranial nerves. Each person has a right and left digastric muscle. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mylohyoid Muscle The mylohyoid muscle or diaphragma oris is a paired muscle of the neck. It runs from the mandible to the hyoid bone, forming the floor of the oral cavity of the mouth. It is named after its two attachments near the molar teeth. It forms the floor of the submental triangle. It elevates the hyoid bone and the tongue, important during swallowing and spe |
