Oral Landmarks for Local Anaesthesia Flashcards
What different types of anaesthesia are used in extractions and restorations/periodontal treatment
- Extractions - All nerves supplying the area need to be anaesthetised. Main supply plus all accessory nerves
- Restoration/periodontal treatment - usually sufficient to block main nerve supply.
What cranial nerve needs to be anaesthetised for dental treatment
Trigeminal - Ophthalmic, Maxillary and Mandibular branches
What are the three different parts of the trigeminal nucleus and what branch does each give rise to
Mesencephalic - Mandibular
Principal - ophthalmic
Spinal - Maxillary
Where do the branches of the trigeminal nerve go through (might be the termination points but i doubt it)
Ophthalmic - Superior Orbital Fissure
Maxillary - Foramen Rotundum
Mandibular - Foramen Ovale
What is the largest cranial nerve
Trigeminal
What are the features of infiltration anaesthesia and where is it used
- Act locally to provide good LA
- Effective on local soft tissues
- Act on teeth where bone is reasonably thin
- Used for maxillary teeth
- Mandibular anterior teeth
Where is the nasopalatine nerve branch of the maxillary branch found
At the front of the hard palate, includes the rugae and dat.
Where is the greater palatine nerve branch of the maxillary branch found
On the left and right of the hard palate (and a bit of the soft palate).
What nerve branches innervate the maxillary teeth
Ant. Sup. alveolar n. = 1, 2 and 3
Mid. Sup. alveolar n. = 4 and5
Post. Sup. alveolar n. = 6, 7 and 8
Where are the pterygoid plexus of veins in danger when using anaesthesia
Posteriorly to upper second molars, danger to the pterygoid plexus of veins buccally.
How would you apply topical anaesthesia
- Dispense a pea sized amount of topical anaesthetic - Use a cotton pledget or cotton roll to pick up topical
- Clean and dry the mucosa before applying the topical
- Retract the lip and apply the gel to the injection site.
What do you do before put the needle in
• Retract • Pull mucosa taut • Patient mouth partially open
Whats the difference between an infiltration and regional block
Infiltration = one branch of nerve Regional = main source of nerve branches, so all branches are blocked
What are some of the branches of the mandibular branch
Lingual
Buccal
Auriculotemporal
Inferior alveolar
On the ramus of the mandible what nerve runs inferiorly to the inferior alveolar nerve
the lingual nerve
What is the pterygomandibular raphe
The pterygomandibular raphe (pterygomandibular ligament) is a ligamentous band of the buccopharyngeal fascia, attached superiorly to the pterygoid hamulus of the medial pterygoid plate, and inferiorly to the posterior end of the mylohyoid line of the mandible.
In an inferior alveolar nerve block (IANB) what nerves are affected
Nerves affected: Inferior alveolar nerve, mental nerve
What is the injection site of an IANB
Mandibular foramen (difficult to locate)
What tissues are anaesthetised in an IANB
all mandibular teeth (pulps and periodontal ligaments); skin of chin, labial mucosa, lower lip
What is a hazard of an IANB
Hazards: parotid gland (anesthetizes facial nerve)
What is lateral, medial and inferior, superior and anterior to the pterygomandibular space
Lateral = ramus
Medial + Inferior = medial pterygoid muscle
Superior - lateral pterygoid
Anterior - buccinator
What can happen if you inject the LA into the parotid gland instead of an IANB
- Facial nerve (traverses the parotid gland)
- Hemifacial paresis (facial nerve palsy)
- Unable to close their eyelids on affected side
- Paralysis will resolve as the effect of the anaesthetic wears off.
- The eye must be protected until motor function is restored.
What can be done to reduce the chances of the LA entering the parotid gland
Ensuring the needle has contacted bone prior to administration of an inferior alveolar nerve block should reduce the chances of entering the parotid gland.
What is the injection site for a buccal nerve block
The retromolar fossa
What tissues are anaesthetised in a buccal nerve block
Skin and mucous membrane of cheek, buccal alveolar mucosa and gingivae of molars (on side of injection).
What nerves are blocked in a mental block
Nerves Affected:
Mental n. and anterior part of inf. alveolar n.
What is the injection site for a mental nerve block
Mental foramen
What tissues are anaesthetised in a mental nerve block
mandibular incisors and canine (pulps, perio. lig. and bone), labial gingiva, skin of chin.
What is the injection site of the lingual nerve block
Anterior and deep into inferior alveolar site
What tissues are anaesthetised in a lingual nerve block
Mucosa of ant. 2/3 of tongue, floor of mouth, lingual alveolar mucosa and lingual gingiva all teeth (on side of injection).
What hazards are there with lingual nerve blocks
Parotid gland shit like the IANB
What is the injection site for a greater palatine nerve block
Greater palatine foramen, can be palpated
What tissues are anaesthetised in a greater palatine nerve block
All hard palatal mucosa and gingiva posterior to maxillary canines on side of injection
What hazards are there in a greater palatine nerve block
Puncture of the greater palatine artery or vein
What are the potential complications of LA
Pain/swelling Spread of acute infection Bleeding Allergy Trauma to anaesthetised tissues Facial nerve palsy
