• The trigeminal nerve arises as a short, thick sensory trunk and a smaller motor component from the ventrolateral aspect of the pons.
• Sensory to the following structures: 1. the face, 2. the greater part of the scalp, 3. the teeth, 4. the oral and nasal cavities, 5. the dura mater
Motor to the following structures: 1. the masticatory muscles, 2. the anterior belly of the digastric, 3. tensor tympani, 4. tensor veli palatini, 5. and the mylohyoid.
ROUTE OF THE TRIGEMINAL NERVE
• The nerve passes anteriorly over the petrous temporal ridge into a tunnel of dura mater (trigeminal or Meckel’s cave) within the middle cranial fossa. Within the cave, the nerve flattens out as the large trigeminal (semilunar) ganglion• And this, in turn, gives rise to three divisions:
V1 - Opthalmic N. (Sensory)V2 - Maxillary N. ( Sensory)V3 -Mandibular N. (Mixed)
THE OPHTHALMIC NERVE
• The superior and the smallest of the trigeminal division, and is wholly sensory. It supplies the following:1. the eyeball,2. the lacrimal gland and conjunctiva,3. part of the nasal mucosa,4. the skin of the nose, eyelids, forehead and part of the scalp.
Passes thru the supraorbital fissure and divides into three branches:1. Lacrimal n.2. Frontal n.3. Nasociliary n.
The Lacrimal Nerve- the smallest of the main ophthalmic branches- enters the orbit through the lateral part of the supraorbital fissure
The Frontal Nerve- the largest of the ophthalmic division- enters the orbit by the supraorbital fissure- has 2 branches: a. Supraorbital N. b. Supratrochlear N.
The Nasociliary Nerve- intermediate size between the frontal and lacrimal nerves- has 4 branches: a. Short ciliary n., b. Long ciliary n., c. Anterior and posterior ethmoidal n. d. Infratrochlear n.
THE MAXILLARY NERVE
- The intermediate division of the trigeminal nerve is wholly sensory.- It leaves the trigeminal ganglion between the ophthalmic and mandibular divisions to pass through the foramen rotundum.
Branches:1. Meningeal Nerve2. Branches to the Sphenopalatine Ganglion3. Zygomatic Nerve4. Posterior Superior Alveolar Nerve5. Infraorbital Nerve
Location of the Branches of the Maxillary Nerve:In the cranial cavity MeningealIn the pterygopalatine fossa Ganglionic, Zygomatic, Posterior Superior AlveolarIn the infraorbital canal Middle superior alveolar, Anterior superior alveolarOn the face Palpebral, Nasal, Superior labial
Infraorbital canal IOForamen
THE MANDIBULAR NERVE
• The largest trigeminal division, and is both sensory and motor,exits the skull through the foramen ovale.• It supplies the following structures: a. the teeth and the gums of the mandible, b. The skin in the temporal region, c. Part of the auricle including the external meatus and tympanum, d. The lower lip, e. The lower part of the face , f. The muscles of mastication, g. The mucosa of the anterior 2/3s of the tongue, h. And the mucosa of the floor of the mouth
N. To Medial Pterygoid MF
Anterior Division 1 2 3 4
N. To Medial Pterygoid MF
Posterior Division1 2 3
Local Infiltration of Individual Teeth
Local Infiltration of Maxillary Teeth (Incisive Fossa)
Local Infiltration of Maxillary Teeth (Canine Ridge)
Local Infiltration of Maxillary Teeth (Canine Fossa)
Local Infiltration ofPalatal Mucosa and Gingiva
ASAN and MSAN Nerve Block (Infraorbital)• Nerves Blocked:1. Terminal branches of the infraorbital nerve2. ASAN3. MSAN