Tiêu đề 4. Mandibular nerve.pdf ✅

FCPS, MS, DDS Admission Preparation Program in Dentistry Farmgate The mandibular nerve is the largest of the three divisions consisting of both sensory and motor fibres all the structures derived from this arch, e.g., muscles of mastication. FCPS, MS, DDS Admission Preparation Program in Dentistry 01638885050 Website: www.purebasic.com.bd MANDIBULAR NERVE The mandibular nerve is the largest of the three divisions of the trigeminal nerve. It is a both sensory and motor fibres. It is a nerve of the first pharyngeal arch, hence supplies from this arch, e.g., muscles of mastication. Course and Relations Mandibular Nerve 1 of the trigeminal nerve. It is a mixed nerve, pharyngeal arch, hence supplies
FCPS, MS, DDS Admission Preparation Program in Dentistry Farmgate The mandibular nerve is the largest cranial fossa as two roots: a larger sensory root and a smaller motor root. The large sensory root arises from lateral convex part of the trigeminal ganglion and immediately leaves the cranial cavity by passing through foramen ovale to en pons, lies deep to the trigeminal ganglion and the sensory root. It also passes through foramen ovale to join the sensory root just below the foramen ovale in the infratemporal fossa, trunk. The mandibular nerve trunk is short and after a short course divides into a small anterior and large posterior division. Relations of Trunk of Mandibular Nerve in the Medial: Lateral: Tensor palati muscl Posterior: Middle meningeal artery. Anterior: Posterior border of lateral pterygoid plate. Branches From the Main Trunk Two branches arise from the main trunk, a sensory branch (nervusspinosus) and a motor branch (nerve to medial pterygoid): 1. Nervusspinosus (meningeal branch): foramen spinosum with middle meningeal artery and supplies the dura mater of the middle cra fossa. 2. Nerve to medial pterygoid: It arises from the medial aspect of the main trunk, close to the otic ganglion traverses through the ganglion and supplies the medial pterygoid from its deep aspect. In addition to medial pterygoid it also Anterior Division The anterior division is mainly motor and gives branches to all muscles of mastication except medial pterygoid, which is supplied by nerve to medial pterygoid from the main The branches from the anterior divisions 1. Masseteric nerve: It emerges at the upper border of the lateral pterygoid, just in front of the temporomandibular joint, passes laterally through the mandibular notch, along with to supply the masseter from its deeper aspect. It also supplies the temporomandibular joint. 2. Deep temporal nerves: These are usually two in number, anterior and posterior. The anterior and posterior temporal nerves emerge at the temporal fossa to supply the temporalis muscle from its deep aspect. 3. Nerve to lateral pterygoid: It runs with the buccal nerve and enters the deep surfaces of both the heads of lateral pterygoid muscle, which it supplies. 4. Buccal nerve: It contains all the sensory fibres of the anterior division. It emerges between the two heads of the lateral pterygoid and courses downwards and forwards onto the buccinator muscle, giving branches to the skin of the cheek. It then pierces the buccinator muscle and supplies the mucus membrane of the cheek and gum of the lower jaw opposite the molars and second premolar teeth. FCPS, MS, DDS Admission Preparation Program in Dentistry 01638885050 Website: www.purebasic.com.bd largest of three divisions of trigeminal nerve. It begins in : a larger sensory root and a smaller motor root. The large sensory root arises from lateral convex part of the trigeminal ganglion and immediately leaves the cranial cavity by passing through foramen ovale to enter the infratemporal fossa. The small motor root arises from the pons, lies deep to the trigeminal ganglion and the sensory root. It also passes through foramen ovale to join the sensory root just below the foramen ovale in the infratemporal fossa, thus forming the main trunk. The mandibular nerve trunk is short and after a short course divides into a small anterior and Relations of Trunk of Mandibular Nerve in the Infratemporal Fossa Medial: Lateral: Tensor palati muscle and otic ganglion. Upper head of lateral pterygoid muscle. Posterior: Middle meningeal artery. Anterior: Posterior border of lateral pterygoid plate. Branches From the Main Trunk Two branches arise from the main trunk, inosus) and a motor branch (nerve to medial pterygoid): Nervusspinosus (meningeal branch): It takes a recurrent course to enter the cranial cavity through foramen spinosum with middle meningeal artery and supplies the dura mater of the middle cra It arises from the medial aspect of the main trunk, close to the otic ganglion traverses through the ganglion and supplies the medial pterygoid from its deep aspect. In addition to medial pterygoid it also supplies tensor palati and tensor tympani muscles. From the Anterior Division The anterior division is mainly motor and gives branches to all muscles of mastication except medial pterygoid, which is supplied by nerve to medial pterygoid from the main anterior divisions are as follows: It emerges at the upper border of the lateral pterygoid, just in front of the temporomandibular joint, passes laterally through the mandibular notch, along with masseteric artery to supply the masseter from its deeper aspect. It also supplies the temporomandibular joint. These are usually two in number, anterior and posterior. The anterior and posterior temporal nerves emerge at the upper border of the lateral pterygoid and ascend up in the temporal fossa to supply the temporalis muscle from its deep aspect. It runs with the buccal nerve and enters the deep surfaces of both the terygoid muscle, which it supplies. It contains all the sensory fibres of the anterior division. It emerges between the two heads of the lateral pterygoid and courses downwards and forwards onto the buccinator muscle, giving to the skin of the cheek. It then pierces the buccinator muscle and supplies the mucus membrane of the cheek and gum of the lower jaw opposite the molars and second premolar teeth. 2 . It begins in the middle : a larger sensory root and a smaller motor root. The large sensory root arises from lateral convex part of the trigeminal ganglion and immediately leaves the cranial cavity by ter the infratemporal fossa. The small motor root arises from the pons, lies deep to the trigeminal ganglion and the sensory root. It also passes through foramen ovale thus forming the main trunk. The mandibular nerve trunk is short and after a short course divides into a small anterior and e and otic ganglion. Upper head of lateral pterygoid muscle. It takes a recurrent course to enter the cranial cavity through foramen spinosum with middle meningeal artery and supplies the dura mater of the middle cranial It arises from the medial aspect of the main trunk, close to the otic ganglion traverses through the ganglion and supplies the medial pterygoid from its deep aspect. In supplies tensor palati and tensor tympani muscles. From the Anterior Division The anterior division is mainly motor and gives branches to all muscles of mastication except medial pterygoid, which is supplied by nerve to medial pterygoid from the main trunk. It emerges at the upper border of the lateral pterygoid, just in front of the masseteric artery to supply the masseter from its deeper aspect. It also supplies the temporomandibular joint. These are usually two in number, anterior and posterior. The anterior and upper border of the lateral pterygoid and ascend up in the It runs with the buccal nerve and enters the deep surfaces of both the It contains all the sensory fibres of the anterior division. It emerges between the two heads of the lateral pterygoid and courses downwards and forwards onto the buccinator muscle, giving to the skin of the cheek. It then pierces the buccinator muscle and supplies the mucus membrane of the cheek and gum of the lower jaw opposite the molars and second premolar teeth.
FCPS, MS, DDS Admission Preparation Program in Dentistry Farmgate N.B. All the branches of anterior division of the mandibular nerve a sensory. From the Posterior Division The posterior division is mainly sensory. It gives the following three branches: 1. Auriculotemporal nerve: This nerve arises by two roots, which after encircling the middle meningeal artery unite to form the single trunk. It runs backwards between the neck of the mandible and the sphenomandibular ligament. Behind the neck of the mandible, it turns upwards and ascends over the root of zygoma to enter the temple behind Distribution: (a) Its auricular branches supply skin of the tragus, upper part of the pinna, external auditory meatus and tympanic membrane. The lower parts of these regions are supplied by great auricular nerve and auricular branch of the vagus nerve. (b) Its articular branches supply the temporomandibular joint. (c) Its superficial temporal branches supply the skin of the temple. (d) It also supplies secretomotorfibres to the parotid gland. 2. Lingual nerve: It is the smaller terminal branch of posterior division of the mandibular nerve. It is sensory to the mucus membrane of anterior two and relations: It begins about 1 cm below the skull pterygoid and then between lateral and medial pterygoids. About 2 cm below the skull it is joined by the chorda tympani nerve. After emerging at the lower border of the lateral pterygoid, it first run downwards and forwards between the ramus of the mandible and medial pterygoid, comes in direct contact with the mandible where the bone is thinned to form a shallow groove below and medial to the last molar tooth, just above the posterior end of the attachments of pterygomandibular raphe above and mylohyoid muscle below. It enters the mouth on the superior surface of the mylohyoid, and then it crosses the styloglossus to reach the lateral surface of the hyoglossus. Finally it lies on the surface of the genioglossus. Here it winds round the submandibular duct (first above, then lateral, then below and finally medial to the duct) and divides into its terminal branches. Distribution: (a) Provides of the gum and anterior two-third of the tongue; (b) Carries preganglionic secretomotorfibres to submandibular and sublingual salivary glands. 3. Inferior alveolar nerve: It is the larger terminal nerve. It is a mixed nerve. It receives all the motor fibres of the trigeminal nerve. Course: It emerges below the lower head of the lateral pterygoid and passes vertically downwards and forward on t medial pterygoid. The nerve lies anterior to inferior alveolar vessels between the sphenomandibular ligament and the ramus of the mandible. Then enters the mandibular foramen in company with inferior alveolar artery, traverses the mandibular canal dividing into mental and incisive branches. Branches: (a) Nerve to mylohyoid arises from the inferior alveolar nerve before it enters the mandibular canal. It pierces the sphenomandibular ligament to anterior belly of digastric muscle. FCPS, MS, DDS Admission Preparation Program in Dentistry 01638885050 Website: www.purebasic.com.bd All the branches of anterior division of the mandibular nerve are motor except buccal nerve which is sensory. From the Posterior Division . is mainly sensory. It gives the following three branches: : This nerve arises by two roots, which after encircling the middle meningeal artery unite to form the single trunk. It runs backwards between the neck of the mandible and the sphenomandibular ligament. Behind the neck of the mandible, it turns upwards and ascends over the root of zygoma to enter the temple behind the superficial temporal vessels. Distribution: (a) Its auricular branches supply skin of the tragus, upper part of the pinna, external auditory meatus and tympanic membrane. The lower parts of these regions are supplied by great and auricular branch of the vagus nerve. (b) Its articular branches supply the temporomandibular joint. (c) Its superficial temporal branches supply the skin of the temple. (d) It also supplies secretomotorfibres to the parotid gland. It is the smaller terminal branch of posterior division of the mandibular nerve. It is sensory to the mucus membrane of anterior two-third of the tongue except vallate papillae. Course and relations: It begins about 1 cm below the skull. It runs first between tensor palati and lateral pterygoid and then between lateral and medial pterygoids. About 2 cm below the skull it is joined by the chorda tympani nerve. After emerging at the lower border of the lateral pterygoid, it first run downwards and forwards between the ramus of the mandible and medial pterygoid, comes in direct contact with the mandible where the bone is thinned to form a shallow groove below and medial to the last molar tooth, just above the posterior end of the mylohyoid line. This groove separates the attachments of pterygomandibular raphe above and mylohyoid muscle below. It enters the mouth on the superior surface of the mylohyoid, and then it crosses the styloglossus to reach the lateral surface he hyoglossus. Finally it lies on the surface of the genioglossus. Here it winds round the submandibular duct (first above, then lateral, then below and finally medial to the duct) and divides into its terminal branches. Distribution: (a) Provides sensory supply to floor of mouth, lingual surface third of the tongue; (b) Carries preganglionic secretomotorfibres to submandibular and sublingual salivary glands. It is the larger terminal branch of the posterior division of mandibular nerve. It is a mixed nerve. It receives all the motor fibres of the trigeminal nerve. Course: It emerges below the lower head of the lateral pterygoid and passes vertically downwards and forward on t medial pterygoid. The nerve lies anterior to inferior alveolar vessels between the sphenomandibular ligament and the ramus of the mandible. Then enters the mandibular foramen in company with inferior alveolar artery, traverses the mandibular canal as far as mental foramen, where it terminates by dividing into mental and incisive branches. Branches: arises from the inferior alveolar nerve before it enters the mandibular canal. It pierces the sphenomandibular ligament to reach the mylohyoid groove. It supplies mylohyoid and 3 re motor except buccal nerve which is : This nerve arises by two roots, which after encircling the middle meningeal artery unite to form the single trunk. It runs backwards between the neck of the mandible and the sphenomandibular ligament. Behind the neck of the mandible, it turns upwards and ascends Distribution: (a) Its auricular branches supply skin of the tragus, upper part of the pinna, external auditory meatus and tympanic membrane. The lower parts of these regions are supplied by great It is the smaller terminal branch of posterior division of the mandibular nerve. It is third of the tongue except vallate papillae. Course . It runs first between tensor palati and lateral pterygoid and then between lateral and medial pterygoids. About 2 cm below the skull it is joined by the chorda tympani nerve. After emerging at the lower border of the lateral pterygoid, it first run downwards and forwards between the ramus of the mandible and medial pterygoid, comes in direct contact with the mandible where the bone is thinned to form a shallow groove below and medial to mylohyoid line. This groove separates the attachments of pterygomandibular raphe above and mylohyoid muscle below. It enters the mouth on the superior surface of the mylohyoid, and then it crosses the styloglossus to reach the lateral surface he hyoglossus. Finally it lies on the surface of the genioglossus. Here it winds round the submandibular duct (first above, then lateral, then below and finally medial to the duct) and divides sensory supply to floor of mouth, lingual surface third of the tongue; (b) Carries preganglionic secretomotorfibres to branch of the posterior division of mandibular nerve. It is a mixed nerve. It receives all the motor fibres of the trigeminal nerve. Course: It emerges below the lower head of the lateral pterygoid and passes vertically downwards and forward on the medial pterygoid. The nerve lies anterior to inferior alveolar vessels between the sphenomandibular ligament and the ramus of the mandible. Then enters the mandibular foramen in company with inferior as far as mental foramen, where it terminates by arises from the inferior alveolar nerve before it enters the mandibular canal. It reach the mylohyoid groove. It supplies mylohyoid and
FCPS, MS, DDS Admission Preparation Program in Dentistry Farmgate (b) Dental branches supply molar and premolar teeth. (c) Mental nerve emerges out through mental foramen to supply skin of the chin and skin and mucus membrane of the lower lip. (d) Incisive branch, supplies canine and incisor teeth. N.B. All the branches of posterior division of the mandibular nerve are sensory except nerve to mylohyoid, which is motor. • Inferior alveolar nerve block (generally called inferior alveolar block or 1A block): It is the most common nerve block performed in dentistry to carry out dental procedures on the mandibular teeth. The anesthetic agent is injected slightly superior to the entry of inferior alveola mandibular foramen being overhung by the lingula. While performing inferior alveolar nerve block, if needle is inserted too far posteriorly, it may enter the parotid gland and damage the facial nerve leading to transient facial palsy. • The lingual nerve is at great risk (10%) during surgical removal of the impacted third molar teeth. The nerve is also at risk during surgical removal of the submandibular salivary gland, during which the submandibular duct must be dissected out care • Referred Pain: It is the pain frequently referred from one branch of mandibular nerve to the other. Thus in patients suffering from tongue cancer, the pain radiates to the ear and to the temporal fossa in the area of distribution of auriculo- below and behind the last molar tooth. At this site the nerve is in contact with the mandible and covered only by mucus membrane. Similarly, pain from teeth is also r region. FCPS, MS, DDS Admission Preparation Program in Dentistry 01638885050 Website: www.purebasic.com.bd supply molar and premolar teeth. emerges out through mental foramen to supply skin of the chin and skin and mucus , supplies canine and incisor teeth. N.B. All the branches of posterior division of the mandibular nerve are sensory except nerve to Clinical correlation (generally called inferior alveolar block or 1A block): It is the most common nerve block performed in dentistry to carry out dental procedures on the mandibular teeth. The anesthetic agent is injected slightly superior to the entry of inferior alveolar nerve into the mandibular foramen being overhung by the lingula. While performing inferior alveolar nerve block, if needle is inserted too far posteriorly, it may enter the parotid gland and damage the facial nerve leading • The lingual nerve is at great risk (10%) during surgical removal of the impacted third molar teeth. The nerve is also at risk during surgical removal of the submandibular salivary gland, during which the submandibular duct must be dissected out carefully from the nerve. • Referred Pain: It is the pain frequently referred from one branch of mandibular nerve to the other. Thus in patients suffering from tongue cancer, the pain radiates to the ear and to the temporal fossa in -temporal nerve. The pain is relieved by dividing the lingual nerve below and behind the last molar tooth. At this site the nerve is in contact with the mandible and covered only by mucus membrane. Similarly, pain from teeth is also referred to the ear and temporal 4 emerges out through mental foramen to supply skin of the chin and skin and mucus N.B. All the branches of posterior division of the mandibular nerve are sensory except nerve to (generally called inferior alveolar block or 1A block): It is the most common nerve block performed in dentistry to carry out dental procedures on the mandibular teeth. r nerve into the mandibular foramen being overhung by the lingula. While performing inferior alveolar nerve block, if needle is inserted too far posteriorly, it may enter the parotid gland and damage the facial nerve leading • The lingual nerve is at great risk (10%) during surgical removal of the impacted third molar teeth. The nerve is also at risk during surgical removal of the submandibular salivary gland, during which the • Referred Pain: It is the pain frequently referred from one branch of mandibular nerve to the other. Thus in patients suffering from tongue cancer, the pain radiates to the ear and to the temporal fossa in temporal nerve. The pain is relieved by dividing the lingual nerve below and behind the last molar tooth. At this site the nerve is in contact with the mandible and eferred to the ear and temporal