Trigémino:
The name comes from literally of the name of trillizos, referring to the fact that this nerve has three greater divisions: ophthalmic (V1), maxillary (V2) and mandibular (V3). It is the main nerve sencitivo of the face and inerva several musculos
The nerve surfaces on the expensive mediolateral of the protuberance like a root sensitiva and a root motora. His ganglion sensitivo or ganglion of gasser this situated in a depression designated cavity trigeminal or cavity of Meckel, in the flat of the cranial pit average.
The axones sensitivos in the expensive distal of the ganglion form the 3 greater divisions (V1,2,3)
The axones engines discurren with the mandibular division
Modality of the nervous fibres
Core
Function
Sensitivas General (aferentes)
Trigeminal Spinal
Trigeminal pontino
Mesencefalico Pain, temperature, tato simple, all the modalities sensitivas generals of the face, the conjuntivas, the bulb of the eye, nasal and oral cavities
Touch discriminativo, propiocepcion and sense of vibration
Motoras Branqueales
(eferentes)
Engine (masticatorio)
Inervación Of the muscles of the mastication (masseter, temporary, pterigoideo lateral and medial, tensors of the timpano, of the veil of the palate, the milohioideos and previous belly of the digastrico)
Real origin. The nerve trigémino presents a complex nuclear mass in which they distinguish : the core intercalado sensitivo, the core engine and, in the periphery, a ganglion: the ganglion trigeminal
subdivide In the following cores:
Core mesencefálico: it Is situated in the mesencephalon to the sides of the aqueduct of the brain. It is formed by derivative neurons of the crests neurales, which did not emigrate to the periphery. They receive aferencia propioceptiva of the husos neuromuscular of the muscles of the mastication and others. The core finds connected with the cores cerebelosos, with the colículo upper and with the cores of the pairs III and IV.
MAURO
Core sensitivo or main. It locates in the bridge and receives mainly aferencia exteroceptiva.
Spinal core or bulbar. It is situated in the marrow oblonga and continues with the gelatinous substance of the two first cervical segments. It receives aferencia mainly of type nociceptivo.
The axones of the neurons of the cores intercalados of the trigémino establish sinapsis with neighbouring structures to guarantee the answers reflect, and through the lemnisco trigeminal, establish sinapsis with the core ventroposteromedial of the thalamus.
Core engine. Called also core masticador, is formed by motoneuronas alpha and gamma. It locates in the bridge, above the core of the facial nerve and inside of the core sensitivo of the trigémino.
Apparent origin. The nerve trigémino originates by two roots that surface of the bridge in the limit between the inferior face and the peduncle cerebeloso half, in the line trigémino-facial:
–The root sensitiva is thick and is formed by the union of 40 to 50 filetes nervous very thin, with appearance aplanado and width of 5 mm. It contains the central prolongation of the neurons aferentes of the ganglion
–The root motora, call also nerve crotafítico-buccinatorio, is much thinner that the root sensitiva. Has 2 mm of width and initiates by some 10?filetes Nervous of the neuroeje, inside and above the root sensitiva. The root motora is constituted by the axones of the core engine of the trigémino
Between both roots finds a small eminence of nervous substance, the língula of Wrisberg or bandeleta of Soemmering.
Divisions Oftalmica (V1)
Has 3 main branches: frontal, lacrimal and nasociliar
The frontal nerve: formed by the supraorbital from the front and the uer cabelludo; the nerve supratroclear from the bridge of the nose, medial portion of the parpado sup. And medial of the front. A small branch sensitiva comes from of the aerial breast of the frontal and joins to the frontal nerve
The nerve lagrimal: it transports information sensitiva of the lateral portion of the parpado, the conjuntiva and the gland lagrimal. The fibres secretomotoras for the gland lagrimal from the VII cranial pair can travel in brief with the same in his peripheral portion
CARLOS
The nerve nasociliar: formed by several terminal branches as they are it the nerve infratoclear (medial portion of the parpado), the nasal external (skin of the wing of the nose until the nasal lobule) and internal (ant. Of the nasal septum and wall lat. Nasal) and the ciliary nerves (bulb of the eye)
Maxillary division (V2)
Formed by the zygomatic nerves, infraorbitario, alveolar superio and palatino
Andl nerve cigomatio: has 2 main branches, the sensitivas of the cheek converge to form the facial zygomatic nerve. This discurre haia backwards along flat of orbits it to join with the maxillary nerve near of the fissure orbitaria
The nerve infraorbitario: formed by cutaneous branches of the upper lip, the medial cheek and the side of the nose. East crosses the foramesn infraorbitario and directs to backwards by the channel infraorbitario, where join the previous branches of the alveolar nerve sup. This combined surfaces on the flat of orbits it and turns into maxillary nerve.
Upper alveolar nerves: they are ant, means andp ost, transport aferencias sensitivas, mainly of the pain, mainly of the upper teeth
Nerves palatinos: they originate in the hard and soft palate and rises to the maxillary nerve by the channel pterigopalatino
Mandibular division (V3)
His component sensitivo is formed by the buccal nerves, lingual, alveolar inferior and auriculotemporal
The buccal nerve: it transports information sensitiva from the buccal region (cheek) included the mucosa of the mouth and the encías, discurre and drills the musculo pterigoideo lat. To join to the trunk of the mandibular nerve
Lingual and alveolar nerves inferior: they transport general sensitivity of all the mandibula, including the teeth, the encías and the two thirds ant. Of the tongue
The nerves sensitivos of the chin and of the thebio inferior converge pairto form the nerve mentoniano, that goes in in the jaw through the foramen mentoniano until going through the mandibular channel. Inside this channel the branches denarias join with the nerve mentoniano to form the inferior alveolar nerve, which continuous and goes out by the foramen mandibular for afterwards join to the main trunk with the lingual nerve
Nerve auriculotemporal: it transports the senibilidad of the expensive laterla of the head and the scalp
THE SENSITIVITY OF THE MENNGES OF THE CRANIAL PITS ANT And HALF IS TRANSPORTED BY THE BRANCH MENINGEA OF THE MANDIBULAR NERVE
