Anatomy - Week 12 PP Flashcards
Blood Supply to the Head and Neck
- It is important to be able to locate the larger blood
vessels of the head and neck - These vessels may become compromised by disease or during such dental procedures as administering local anesthetic injections
Major Arteries of the
Face and Oral Cavity
-Common carotoid artery
-Internal carotoid artery
-External carotid artery
Common carotid artery
-arises from the aorta and subdivides into the internal and external carotid arteries
Internal carotid artery
- supplies blood to the brain and eyes
External carotid artery
-provides the major blood supply to the face and mouth
External Carotid Artery branches into..
Facial artery - 6 braches supply: pharyngeal muscles, soft palate, tonsils, posterior tongue, submandibular gland, muscles of the face, nasal septum, nose and eyelids
◦ Lingual artery -Several branches supply: tongue, floor of the mouth, lingual gingiva a portion of the soft palate and tonsils
◦ Maxillary artery – Divides into the inferior alveolar, ptergyoid and pterygopalatine
◦ Mandibular artery
Muscles of facial expression blood supply
Branches and small arteries from maxillary, facial,
and ophthalmic arteries
Maxillary bones blood supply
anterior, middle, and posterior alveolar arteries
Maxillary teeth blood supply
anterior, middle, and posterior alveolar arteries
Mandible blood supply
inferior alveolar arteries
mandibular teeth blood supply
inferior alveolar artieries
tongue blood supply
lingual artery
muscles of mastication blood supply
facial arteries
Major Veins of the
Face and the Oral Cavity
- Maxillary vein
- Retromandibular vein
- External jugular vein
- Subclavian vein
- Facial vein
- Common facial vein
- Deep facial vein
- Lingual veins
- Internal jugular vein
Nerves of the Head & Neck
- Understanding the nerves of the head and neck is
important for the use of local anesthesia during dental treatment - The nerves are related to certain conditions of the face, such as facial paralysis
Nervous System is composed of…
Central nervous system:
-brain
-spinal cord
Peripheral nervous sustem
*Autonomic nervous system - automatically done
-Sympathetic - fight & flight
-Parasympathetic - rest & digest responses
*Somatic nervous system - under your control
Cranial Nerves
There are 12 pairs of cranial nerves, all connected to the brain
- These functions serve both sensory and motor functions
- The cranial nerves are generally named for the area or function they serve and are also identified with the use of Roman Numerals
Olfactory Nerve
Sense of Smell
Optic Nerve
Sense of sight
Oculomotor
movement of eye muscles
Trochlear nerve
movement of eye muscles
Trigeminal Nerve
Movement of muscles of mastication an other cranial muscles
General sensations for face, head, skin, teeth and oral cavity & tongue
Cranial Nerve V
- Is the primary source of innervation for the oral cavity
- Subdivides into 3 main divisions:
1. Ophthalmic division (V1)
2. Maxillary division (V2)
3. Mandibular division (V3)
Maxillary Division (V2)
-Supplies the maxillary teeth, periosteum, mucous membrane, maxillary sinuses, and soft palate
- Subdivides into the:
◦ Nasopalatine nerve
◦ Greater palatine nerve
◦ Anterior superior alveolar nerve ◦ Middle superior alveolar nerve ◦ Posterior superior alveolar nerve
Nasopalatine Nerve
- Passes through the incisive foramen
- Supplies the mucoperiosteum palatal to the maxillary anterior teeth
Anterior/Greater Palatine Nerve
- Passes through the posterior palatine foramen and forward over the palate
- Supplies the mucoperiosteum, intermingling with the nasopalatine nerve
Anterior Superior Alveolar Nerve (ASA)
- Supplies the maxillary central, lateral, and cuspid teeth, along with their periodontal membranes and gingivae
- Also supplies the maxillary sinus
Middle Superior Alveolar Nerve (MSA)
- Supplies the maxillary first and second premolars, the mesiobuccal root of the maxillary first molar, and the maxillary sinus
Posterior Superior Alveolar Nerve
(PSA)
- Supplies the other roots of the maxillary first molar and the maxillary second and third molars
- Also branches forward to serve the lateral wall of the maxillary sinus
Mandibular Division
of the Trigeminal Nerve - 3 main subdivisions
- The buccal nerve
- The lingual nerve
-The inferior alveolar nerve
The buccal nerve
- supplies branches to the buccal mucous membrane and mucoperiosteum of the mandibular molar teeth
The lingual nerve
- supplies the anterior two thirds of the tongue and gives off branches to supply the lingual mucous membrane and mucoperiosteum
the inferior alveolar nerve
-further subdivides into the mylohyiod nerve, mental nerve, incisive nerve, and small dental nerves that supply the molar and premolar teeth, alveolar processes and periosteum
Inferior Alveolar Nerve (IAN)
- Mylohyoid nerve
◦ supplies the mylohyoid muscles and the anterior belly of the digastric muscle. - Small dental nerves
◦ supply the molar and premolar teeth, alveolar process, and periosteum. - Mental nerve
◦ moves outward and anteriorly through the mental foramen and supplies the chin and mucous membrane of the lower lip. - Incisive nerve
◦ continues anteriorly within the bone and gives off small branches to supply the incisor teeth
Cranial Nerve VII - Facial Nerve
Mixed Nerve
-Sensory portion concerned with taste; motor portion controls facial expression and secretion of tears and saliva
- Damage causes sagging facial muscles and a distored sense of taste
Injection Techniques
The location and innervation of the tooth or teeth to be anesthetized will determine where topical anesthetic is placed, and the type of injection given
◦ Maxillary anesthesia
◦ Palatal anesthesia
◦ Mandibular anesthesia
Maxillary Anesthesia
- Local anesthesia injection techniques differ from mandibular approaches because of the porous nature of alveolar cancellous bone in the maxilla.
- Allows the anesthetic solution to diffuse through the bone and reach the apices of the teeth in a different manner than the mandible
Injection Techniques - Maxilla
- Local infiltration is completed by injecting into a small, isolated area
- Field block refers to the injection of anesthetic near a larger terminal nerve branch
- Nerve block occurs when local anesthetic is deposited close to a main nerve trunk
Posterior Superior Alveolar Nerve Block anestheizes..
◦ Maxillary 2nd and 3rd Molars and the distobuccal and
lingual root of the 1st molar and surrounding buccal
gingiva
Middle Superior Alveolar Nerve block anesthesizes….
◦ Maxillary 1st and 2nd premolars and the mesiobuccal
root of the 1st molar and surrounding buccal gingiva
Anterior Superior Alveolar Nerve Block anesthesizes…
Maxillary central, lateral and cuspid teeth and the
surrounding buccal gingiva
Palatal Anesthesia
- Local anesthesia in the palatal area may be
necessary for procedures that involve the soft
tissues of the palate
Greater Palatine Nerve
Passes through the posterior palatine foramen
Innervates the mucosa of the hard palate (except lingual to the
maxillary incisors)
Nasopalatine Nerve
Passes through the incisive foramen
Innervates the gingiva palatal to the maxillary anterior teeth
Mandibular Anesthesia
- Because of the dense, compact nature of the mandibular bone, anesthetic solution does not
diffuse easily through it - Block anesthesia is frequently required for most mandibular teeth
- Solution is injected near a major nerve, and the entire area served by that nerve branch is numbed
◦ Inferior alveolar nerve block (mandibular nerve block)
◦ Buccal nerve block
◦ Incisive nerve block
Mandibular Innervation - Buccal Nerve
- Buccal Nerve
◦ Supplies branches to the buccal mucous membrane of the mandibular molars
Mandibular Innervation - Lingual Nerve
- Lingual Nerve
◦ Supplies the anterior 2/3rds of the tongue and the lingual mucous membrane
Mandibular Innervation - Inferior Alveolar
- Inferior Alveolar (subdivides)
◦ Small dental nerves supply the molar and premolar teeth
◦ Mental nerve - exits through the mental foramen and supplies the chin and mucous membrane of the lower lip
◦ Incisive/mental nerve – continues anteriorly within the bone and branches supply the incisor teeth
Periodontal Ligament Injection
- Injection of the anesthetic solution under pressure directly into the periodontal ligament and
surrounding tissues - Periodontal ligament injection is generally an adjunct (addition) to conventional techniques
Other Injection Techniques
- Intra-osseus
- Gow-Gates Mandibular Block - higher up on nerve branch, main branch of trigemal (not performed often)
- Vazirani-Akinosi Mandibular Block
