Head and Neck 2020
Page 1: Introduction to Head and Neck Anatomy
Focus on anatomical considerations for local anesthesia
Key nerves involved:
Mandibular nerve
Lingual nerve
Inferior alveolar nerve
Mental nerve
Inferior dental plexus
Presented by Darlene O'Brien, RDH, MSDH
Page 2: Osteology Review of the Face
Important foramina and processes:
Supraorbital foramen
Superior orbital fissure
Infraorbital foramen
Maxilla
Ramus
Mental protuberance
Mental foramen
Canine eminence
Zygomatic arch
Infraorbital margin
Nasal septum
Page 3: Osteology Review - Cranial Foramina
Anatomical structures to recognize:
Foramen magnum
Foramen spinosum
Foramen ovale
Infraorbital fissure
Foramen lacerum
Mandibular fossa
Page 4: Further Osteology Review
Key structures:
Incisive fossa and foramen
Median palatine suture
Greater palatine foramen
Lesser palatine foramen
Hamulus
Pterygoid fossa
Maxillary tuberosity
Traverse palatine suture
Palatine process of the maxillae
Page 5: Mandible Structure
Key aspects of the mandible:
Coronoid process
Head of mandible
Mandibular notch
Ramus
External oblique line
Mental foramen
Coronoid notch
Page 6: Mandible - Posterior View
Identifying structures on posterior view:
Angle of mandible
Mylohyoid groove
Mandibular foramen
Lingula
Page 7: Trigeminal Nerve Overview
Largest of the twelve cranial nerves
Main sensory nerve for head and neck
Composed of three branches
Page 8: Trigeminal Nerve Branches
Significant branches:
Nasociliary nerve
Frontal nerve
Lacrimal nerve
Areas served include:
Cornea, conjunctiva, eyeball, orbit, frontal and ethmoid sinuses
Page 9: Trigeminal Nerve Sensory Pathway
Exits skull via foramen rotundum
Enters pterygopalatine fossa behind and below the eye
Serves sensory functions for:
Skin of the side of the nose
Cheek, eyelids, midface
Nasopharynx, tonsils, palate, maxillary sinus
Gingiva, teeth of the upper jaw
Page 10: Key Foramens and Structures
Important anatomical openings:
Frontal sinus
Posterior ethmoidal foramen
Orbital process of palatine
Optic foramen
Sphenopalatine foramen
Sella turcica
Probe configurations related to foramina
Page 11: Trigeminal Nerve - Pterygopalatine Fossa
Contains branches including:
Zygomatic nerve:
Zygomaticotemporal: sensory to skin on the forehead
Zygomaticfacial: sensory to skin on the cheek
Page 12: Additional Nerve Branches
Posterior superior alveolar nerve
Pterygopalatine nerves:
Nasal branches
Nasopalatine nerve
Descending palatine branches:
Greater palatine nerve
Lesser palatine nerve
Page 13: Infraorbital Nerve
Enters orbit via inferior orbital fissure
Courses anteriorly via infraorbital canal
Provides two branches:
Middle superior alveolar nerve
Anterior superior alveolar nerve
Page 14: Maxillary Innervation Overview
Direct branches from maxillary division of trigeminal nerve
Path through posterior superior alveolar foramina
Provides sensation to maxillary molars, gingiva, and surrounding areas
Page 15: Posterior Superior Alveolar Nerve Functions
Supplies sensation to:
DB and L root of maxillary first molar
Sensation to facial gingiva, alveolar bone of specified teeth
Page 16: More on Maxillary Innervation
Posterior superior alveolar nerve details
Additional branches supplying maxillary area
Page 17: Infraorbital Nerve Description
Runs through infraorbital canal beneath orbit
Exits thru infraorbital foramen
Supplies sensation to:
Nose
Under-eye region
Inside upper lip
Page 18: Additional Maxillary Innervation Points
Branch of infraorbital nerve traveled anteriorly
Sensory to MB root of maxillary first molar and both premolars
Page 19: ASA Nerve Functionality
Supplies sensation to maxillary anterior teeth
Provides sensation to facial gingiva, periodontal ligament, and alveolar bone
Page 20: Descending Palatine Nerve
Runs through pterygopalatine canal
Exits palate through greater palatine foramen
Supplies posterior 2/3 of palate and gingiva of maxillary molars and premolars
Page 21: Lesser Palatine Nerve Pathway
Exits through lesser palatine foramina
Supplies soft palate and tonsil area
Page 22: Premaxilla Innervation
Branch of pterygopalatine nerve
Exits through incisive foramen
Supplies sensation to premaxilla area and gingiva, not pulps
Page 23: Mandibular Nerve Overview
Largest branch, mixed nerve
Contains both sensory and minor motor functions
Exits through foramen ovale into infratemporal fossa
Page 24: Mandibular Nerve Boundaries
Defined by:
Ramus of mandible
Lateral pterygoid plate
Maxillary tuberosity
Greater wing of sphenoid
Medial pterygoid muscle
Parotid region
Page 25: Fossa Contents Related to Trigeminal Nerve
Contains:
Medial pterygoid muscle
Maxillary arteries and veins
Pterygoid plexus
Page 26: Clinical Significance of Trigeminal Nerve
Maxillary injections: Potential for hematoma due to pterygoid plexus penetration
Mandibular injections: Risk of infection or hematomas from IA penetration
Page 27: Trigeminal Nerve Motor Root
Arises from motor cells in pons and medulla oblongata
Emerges through foramen ovale with sensory root
Page 28: Muscles Innervated by Motor Root
Muscles of mastication:
Masseter
Temporalis
Medial pterygoideus
Lateral pterygoideus
Mylohyoid
Anterior digastric
Page 29: Trigeminal Nerve Sensory Functions
Innervates sensations to:
Skin, tongue, mucous membranes, mandibular teeth, periodontal tissues, and TMJ
Page 30: Key Branches of Trigeminal Nerve V3
Identifies branches including:
Buccal nerve
Auriculotemporal nerve
Lingual nerve
Inferior alveolar nerve
Page 31: Buccal Nerve Functionality
Provides sensory innervation in the buccal gingiva region
Does not innervate lower lip or buccinator muscle
Page 32: Incisive and Mental Nerve
Largest branch, travels with IA artery
Divides into terminal branches including incisive and mental nerve
Page 33: Mandibular Nerve Innervating Areas
Innervates mandibular teeth to midline, body of mandible, buccal mucoperiosteum
Page 34: Mandibular Canal Structure
Foramen on medial surface
Enters mandibular canal via mandibular foramen
Page 35: Anterior Division Sensory Innervation
Drops downward and forward into the pterygomandibular raphe
Provides sensory innervation to anterior 2/3 tongue and floor of mouth
Page 36: Incisive Nerve's Location
Remains in the mandibular canal
Innervates anterior teeth and relevant periodontal structures
Page 37: Mental Nerve Functions
Exits at the mental foramen
Innervates chin, lower lip, and adjacent facial soft tissue
Page 38: Acknowledgments
Presentation courtesy of M. Cuddy, DMD
Page 39: Dental Plexus Overview
Network of nerves innervating roots of all teeth, bone, and periodontal structures
Includes dental branches, interdental branches, and interradicular branches
Page 40: Trigeminal Nerve Summary Schematic
Important foramina:
Superior orbital foramen
Foramen rotundum
Foramen ovale
Infraorbital foramen
Mandibular foramen
Mental foramen
Page 41: General Rule of Nerve Innervation
Nerves in bone supply teeth and bone
Nerves outside bone supply soft tissue
Page 42: Citations and Resources
A list of useful websites and references relevant to trigeminal nerve anatomy and dental anesthesia.