Trigeminal Nerve - Mandibular Division PDF

Trigeminal Nerve – Mandibular Branch (V3) Gulshana Choudhury Module: Oral and Dental Sciences GDC Learning Outcomes 1.1.5 Describe relevant and appropriate dental, oral, craniofacial and general anatomy and explain their application to patient management Intended Learning Outcomes Describe t...

Trigeminal Nerve – Mandibular Branch (V3) Gulshana Choudhury Module: Oral and Dental Sciences GDC Learning Outcomes 1.1.5 Describe relevant and appropriate dental, oral, craniofacial and general anatomy and explain their application to patient management Intended Learning Outcomes Describe the function of the mandibular branch of the trigeminal nerve (CN V3) Outline the anatomical regions it supplies Explain the relevance of the mandibular branch of the trigeminal nerve to dentistry  3 terminal branches of trigeminal nerve innervate; skin, mucous membranes and sinuses of face Provide sensation to mandibular teeth Local anaesthetic Why do I need to know this?  Acland's Video Atlas of Human Anatomy Resources Anatomy.tv Teach me Anatomy Trigeminal Nerve Derivatives of 1st pharyngeal arch The largest cranial nerve Knowledge of this nerve is very important for dental professionals 3 Divisions Ophthalmic (V1) Maxillary (V2) Mandibular (V3) Mandibular Branch (V3) Largest of the 3 divisions of the Trigeminal nerve Leaves skull at Foramen Ovale Contains both sensory and motor fibres Supplies teeth and gingivae of mandible Skin of temporal regions (side of face) Part of ear Lower lip Lower part of face Muscles of mastication - motor Anterior 2/3rds of tongue What is supplied? Sensory Motor 1. Mandibular teeth & supporting 1. Muscles of mastication structures 2. Mylohyoid 2. Mucosa of anterior 2/3 tongue & floor of mouth 3. Anterior belly of digastric 3. Skin of lower face 4. Tensor veli palatini 4. Parts of temporal region and outer 5. Tensor tympani ear  Originates from 3 sensory nuclei and 1 motor nucleus Extends from midbrain to medulla Anatomical Course Shortly after it leaves skull it divides into a Small Anterior trunk Larger Posterior trunk Branches from nerve before division: 1. Meningeal branch 2. Nerve to medial pterygoid muscle Branches of V3 Anterior Trunk Branches Mainly motor nerves - supply muscles of mastication 1. Masseteric nerve 2. Deep temporal nerves 3. Nerve to lateral pterygoid muscle 4. Long buccal nerve 1 sensory branch - skin of cheek and mucous membrane Posterior Trunk Branches 3 sensory and 1 motor 1. Auriculotemporal nerve Supply area above and in front of ear 2. Lingual nerve Anterior 2/3rd of tongue, joined by branch of facial nerve (chorda tympani), secretive motor function 3. Inferior alveolar nerve Sensation to lower teeth, branches go through to mental foramen and become mental nerve, also innervates lower chin 4. Mylohyoid nerve - only motor nerve of posterior division Muscles of mastication Medial pterygoid nerve: (Motor) Deep and superficial head; originate from maxillary tuberosity and heads join to attach to medial surface of ramus Enters deep surface of the muscle Also supplies tensor tympani & tensor veli palatini Dampen loud sounds (chewing, shouting) Opens auditory tube during yawning or swallowing (ears popping) Equalised pressure between middle ear and nasal pharynx Action: Elevates the jaw Muscles of mastication Masseter Masseteric nerve is first branch of anterior trunk Crosses to masseter between coronoid process & condyle of mandible Gives an articular branch to TMJ Elevates the mandible (mouth closing) Temporalis Anterior & deep temporal nerves Elevates the mandible (mouth closing) Lateral pterygoid Nerve to lateral pterygoid may run part way with long buccal nerve Depresses mandible (mouth opening) Protrudes and lateral movements also Long Buccal Nerve The only sensory branch of the anterior trunk Emerges between heads of lateral pterygoid & runs on lateral surface of buccinator muscle in cheek, close to retromolar fossa of mandible Gives branches to skin of cheek Pierces buccinator to supply buccal sulcus & buccal gingivae of mandibular molars & premolars Auriculotemporal Nerve (A) First branch of posterior trunk Sensory Autonomic to parotid gland due to fibres from otic ganglion Runs alongside glossopharyngeal nerve 2 roots unite & run backwards under lateral pterygoid muscle to lie between condyle & sphenomandibular ligament Emerges between TMJ & external auditory meatus Finally ascends on side of head Lingual Nerve 2nd branch of posterior trunk Sensation to anterior 2/3rd of tongue and floor of mouth Sensory Unites with chorda tympani branch of facial nerve & receives parasympathetic fibres for submandibular & sublingual glands Emerges from under lateral pterygoid muscle & curves downwards & forwards between ramus of mandible & medial pterygoid muscle i.e. the pterygomandibular space Lies anterior to but deeper than inferior alveolar nerve Then passes towards floor of mouth Lingual Nerve Twists around the submandibular duct Enters tongue behind sublingual salivary gland Supplies: 1.Mucosa covering anterior 2/3 dorsum of tongue 2.Under surface of tongue 3.Floor of mouth 4.Lingual gingivae of mandibular teeth  Provides general sensation to pulps of posterior teeth Inferior Alveolar (dental) Nerve Sensory and motor Descends deep to lateral pterygoid muscle behind lingual nerve Enters Mandibular Foramen Travels in inferior dental or mandibular canal in mandible Divides near premolars into mental nerve & incisive nerve Mental nerve emerges at mental foramen Incisive nerve runs anteriorly in incisive canal Pathway of Inferior Alveolar Nerve Branches of Inferior Alveolar Nerve Mylohyoid nerve (B) Given off just before mandibular foramen Runs in mylohyoid groove to supply mylohyoid muscle & anterior belly of digastric (motor) It depresses the mandible (on a fixed hyoid) or elevates the hyoid in swallowing Branches of Inferior Alveolar Nerve Inferior Alveolar Nerve Supplies mandibular molars & premolars & supporting structures (e.g. gingivae) Mental nerve: Supplies skin of chin & lower lip & labial gingivae of anterior mandibular teeth Incisive nerve: Innervates mandibular incisors & canines Mandibular nerve (cranial nerve V3) | Acland's Video Atlas of Human Anatomy  ID Nerve Block Will also spread to lingual nerve - numbness of tongue - how close the lingual nerve is to the alveolar nerve Summary The trigeminal nerve is the the largest and 5th cranial nerve The trigeminal nerve has three divisions; ophthalmic, maxillary and mandibular The mandibular nerve leaves via foramen ovale The mandibular branch of the trigeminal nerve supplies the mandibular teeth and supporting structures, mucosa of the anterior 2/3 tongue and floor of mouth and muscles of mastication https://app.sli.do/event/5tK3dJmSTbUD1sjvhsZiGc References https://teachmeanatomy.info/head/cranial-nerves/trigeminal-nerve/ https://www.anatomy.tv/titles https://aclandanatomy.com/ Norton, N.S. and Netter, F.H. (2017) Netter's head and neck anatomy for Dentistry. Elsevier (Chapter 8 and 21) Liebgott, B. (2018) The anatomical basis of Dentistry. PHILADELPHIA (U.A.): SAUNDERS.