Anatomy of Maxillary and Mandibular Nerves PDF

Anatomy of the neck Maxillary and mandibular nerves By Dr. Rania Elsyade Assistant professor of anatomy and embryology  Objectives By the end of this lab, students will be able to: - Describe the anatomy of the maxillary an...

Anatomy of the neck Maxillary and mandibular nerves By Dr. Rania Elsyade Assistant professor of anatomy and embryology  Objectives By the end of this lab, students will be able to: - Describe the anatomy of the maxillary and mandibular nerves.  Describe the anatomy of the trigeminal nerve ✓ The fifth cranial nerve. ✓ It has large sensory and small motor roots (Mixed motor and sensory). ✓ The large sensory root relay in the trigeminal ganglion and has three branches: 1. Ophthalmic nerve (CN V1) 2. Maxillary nerve (CN V2) 3. Mandibular nerve (CN V3)  Describe the anatomy of the Maxillary nerve Origin: ✓ It is the second division of the trigeminal nerve. ✓ It is pure sensory. ✓ It arises from the trigeminal ganglion in the middle cranial fossa. Course: In the middle cranial fossa, the maxillary nerve runs forward in the lateral wall of the cavernous sinus. It passes through the foramen rotundum to enter the pterygopalatine fossa.  Describe the anatomy of the Maxillary nerve Course: Then, it passes through the pterygomaxillary fissure to enter the infratemporal fossa. Then, it passes through the inferior orbital fissure to enter the orbit as the infraorbital nerve. Termination: The infraorbital nerve runs forward on the floor of the orbit in infraorbital groove → infraorbital canal → infraorbital foramen → the face.  Describe the anatomy of the Maxillary nerve Branches: A) In the cranial cavity: Meningeal branch. Arises as the maxillary nerve in the lateral wall of the cavernous sinus. Supplies the dura mater of the middle cranial fossa. B) In the pterygopalatine fossa Ganglionic branches: 2 roots to the pterygopalatine ganglion.  Describe the anatomy of the Maxillary nerve, Branches: C) In the infratemporal fossa 1- Zygomatic nerve. Enters the orbit through the inferior orbital fissure → then, it runs forward along the lateral wall of the orbital cavity. It ends by dividing into 2 terminal branches: Zygomaticofacial → runs through the zygomaticofacial foramen to enter the face. Zygomaticotermporal → runs through the zygomaticotemporal foramen to enter the temporal fossa. 2- Posterior superior alveolar nerve Enters the posterior surface of the maxilla. Supplies the upper 3 molar teeth.  Describe the anatomy of the Maxillary nerve Branches: D) Branches of the infraorbital nerve: In the orbit 1. Middle superior alveolar nerve Descends along the lateral wall of the maxillary sinus. Supplies the upper 2 premolars. 2. Anterior superior alveolar nerve Descends along the anterior wall of the maxillary sinus. Supplies the canine and the incisors. In the face 1. Palpebral branch → the lower eye lid. 2. Nasal branch → the side of the nose. 3. Labial branch → the upper lip. Describe the anatomy of the Maxillary nerve Test your self  Describe the anatomy of the Mandibular nerve Origin: small motor root large sensory root It is the 3rd division of the trigeminal nerve. It is formed by 2 roots: large sensory and small motor. Course: ✓ The 2 roots leave the cranial cavity through the foramen ovale. ✓ Just below the foramen ovale, The 2 roots unite to form the main trunk of the mandibular nerve. ✓ It descends vertically in the infratemporal fossa infront of the middle meningeal The main trunk of the artery between the lateral pterygoid mandibular nerve. laterally and the tensor palati medially.  Describe the anatomy of the Mandibular nerve small anterior divisions large posterior divisions Termination: It divides into 2 terminal divisions undercover of the lateral pterygoid muscle; small anterior and large Nervus spinosus posterior. Branches: A) From the trunk (1 sensory + 1 motor): 1- Nervus spinosus Enters the cranial cavity through the foramen spinosum with the middle meningeal artery. Supplies the dura mater of the middle cranial fossa (sensory nerve).  Describe the anatomy of the Mandibular nerve tensor tympani muscle 2- Nerve to medial pterygoid (supplies 3 muscles) Supplies the medial pterygoid muscle (motor nerve). Gives 2 small branches that tensor palati muscle pass through the otic ganglion without relay to supply the tensor palati and the tensor tympani muscle. Nerve to tensor palati Nerve to medial pterygoid medial pterygoid muscle  Describe the anatomy of Nerve to the lateral pterygoid the Mandibular nerve Deep temporal nerves Branches: B) From the anterior division: 3 motor and 1 sensory 1- Nerve to the lateral pterygoid (2 in number) 2- Deep temporal nerves (2 in number): Buccal nerve Supplies the temporalis muscle. 3- Nerve to masseter (2 in number): 4- Buccal nerve Emerges between the 2 heads of the lateral pterygoid muscle. Supplies the skin and the mucous membrane of the check. (The only sensory nerve of the anterior division).  Describe the anatomy of the Mandibular nerve Branches: C) From the posterior division: three branches arise deep to the lateral pterygoid muscle. 1- Auriculo temporal nerve: It arises by 2 roots that encircle the middle meningeal artery, just below the foramen spinosum. 2- Lingual nerve: (in front of the Inferior alveolar nerve) Auriculo temporal nerve 3-Inferior alveolar nerve: (behind the lingual nerve) Inferior alveolar nerve Both emerge at the lower border of the lateral pterygoid Lingual nerve muscle.  Describe the anatomy of the Mandibular nerve 1- Auriculo-termporal nerve Course: It enters the substance of the parotid gland and leaves the upper pole of the parotid gland to reach the lateral side of the scalp. Distribution: a. Sensory fibers: The skin of the temporal region, lateral surface of the auricle. The external auditory canal. The outer surface of the tympanic membrane. The parenchyma of the parotid gland. The temporomandibular joint. b. Autonomic fibers: Parasympathetic → secretomotor to the parotid gland. Sympathetic → vasomotor to the blood vessels of the parotid gland.  Describe the anatomy of the Mandibular nerve 2- Lingual nerve: It joins the chorda tympani branch of the facial nerve. Describe the anatomy of the Mandibular nerve 2- Lingual nerve: Course: It descends on the lateral surface of the medial pterygoid muscle deep to the ramus of the mandible. It enters the floor of the mouth by passing behind and below the last molar teeth (dangerous position). Then, it enters the submandibular region where it runs forward on the lateral surface of the hyoglossus muscle deep to the mylohyoid muscle. Finally, it reaches the genioglossus muscle, hooking around the submandibular duct. Termination: It ends on the undersurface of the tongue by dividing into 2 terminal branches to the anterior 2/3 of the tongue and the floor of the mouth. Describe the anatomy of the Mandibular nerve 2- Lingual nerve: Distribution: a. Sensory fibers General sensation from: The anterior 2/3 of the tongue. The floor of the mouth. The gum of the lower teeth. The parenchyma of the submandibular & sublingual glands. Taste sensation from: The anterior 2/3 of the tongue (through chorda tympani nerve). b. Autonomic fibers Parasympathetic (through chorda tympani nerve) → secretomotor to the submandibular and the sublingual salivary Lingual nerve glands. Submandibular ganglion Sympathetic → vasomotor to the blood vessels of the submandibular and the sublingual glands.  Describe the anatomy of the Mandibular nerve 2- Inferior alveolar nerve: Course: behind the lingual nerve and in front of the inferior alveolar vessels. It descends between the medial pterygoid muscle medially and the ramus of the mandible laterally. Inferior alveolar nerve It enters the mandibular foramen to run in the mandibular canal. It ends at the level of the mental foramen, by dividing into incisive and mental branches.  Describe the anatomy of the Mandibular nerve 2- Inferior alveolar nerve: Distribution: 1. Mylohyoid nerve It arises 1cm before the inferior alveolar nerve enters the mandibular foramen → then it runs in the mylohyoid groove. It supplies the mylohyoid muscle and the anterior belly of the digastric muscle (the only muscular branch of the posterior division).  Describe the anatomy of the Mandibular nerve 2- Inferior alveolar nerve: Distribution: 2. Dental nerves They arise from the inferior alveolar nerve in the mandibular canal. They supply the teeth of the lower jaw posterior to the canine (molar and premolar).  Describe the anatomy of the Mandibular nerve 2- Inferior alveolar nerve: Distribution: 3. Incisive nerve It arises at the level of the mental foramen. It supplies the canine and the incisive teeth. 3. Mental nerve It emerges from the mental foramen. It supplies the skin and the mucous membrane of the lower lip.