Local anaesthetics 1 Flashcards
What is the definition of anaesthesia?
State of controlled, temporary loss of sensation or awareness induced for medical purposes
What is the definition of general anaesthesia?
Suppresses central nervous system
Consciousness is lost, total lack of sensation
What is the definition of sedation?
Suppresses CNS to a lesser degree than GA, inhibiting anxiety and creation of long term memory
What is the definition of local anaesthesia?
Block transmission of nerve impulse
Loss of sensation in specific areas of the body
Which sensory nuclei does the trigeminal nerve arise from?
- principal sensory
- spinal
- mesencephalic
Where does the opthalmic nerve come out from onto the face?
Superior orbital fissure
Where does the maxillary nerve come out from onto the face?
Foramen rotundum
Where does the mandibular nerve come out from onto the face?
Foramen ovale
Which branch of the trigeminal nerve is also motor?
Mandibular nerve
What does the trigeminal nerve supply?
Predominantly supplies the sensory distribution to the oro-facial tissues
What 3 branches does the ophthalmic nerve split into?
- frontal- supraorbital, supratrochlear
- nasociliary- long ciliary, short ciliary, nasal, ethmoidal
- lacrimal
What structures does the ophthalmic nerve supply on the face?
- upper eyelid and associated conjuctiva
- eyebrow
- forehead
- scalp to lambdoid structure
What structures does the ophthalmic nerve supply on the skull?
- roof of orbit
- frontal, ethmoid, sphenoid sinus
What structures does the ophthalmic nerve supply to the eye?
- intraocular structures, eg. cornea
- lacrimal gland and sac
What does the maxillary branch supply?
- skin of lower eyelid
- prominence of cheek
- lateral part of nose
- part of temple
- upper lip
- inferior posterior portion of nasal cavity
- upper teeth
- palate mucosa
- buccal gingiva
What does the maxillary branch split into?
- meningeal
- zygomaticus- zygomaticofacial and zygomaticotemporal
- greater and lesser palantine
- nasopalatine
- posterior superior alveolar nerve
- pharyngeal
- infraorbital- anterior superior alveolar nerve and middle superior alveolar nerve
What are the branches of the mandibular nerve?
- lingual, buccal, auriculotemporal
- inferior alveolar- mental, nerve to mylohoid
- other motor branches
What does the motoric mandibular nerve supply anteriorly?
- masseter
medial and lateral pterygoid - tensor tympani
- tensor veli palatini
- temporal
What does the motoric mandibular nerve supply posteriorly?
- mylohyoid
- anterior belly of digastric
What does the sensoric branch of the mandibular nerve supply?
- buccal mucosa
- mucoperiosteum of lower teeth
- anterior 2/3rd of tongue
- chin
- lower lip
- auricular
- temporal region of scalp
For an ID block which nerve do we numb?
Inferior alveolar nerve
Which areas are numb for an ID block?
- lower molars ipsilateral
- ipsilateral half of lip
- ipsilateral half of tongue
Where is LA depot placed for an ID block?
Pterygomandibular space
What is the medial/inferior border of pterygomandibular space?
medial pterygoid muscle
What is the lateral border of pterygomandibular space?
Medial surface of the ramus
What is the anterior border of the pterygomandibular space?
Pterygomandibular raphe and insert fibres of buccinator
What is the superior border of the pterygomandibular space?
Lateral pterygoid muscle
Which nerve is numb in long buccal nerve block?
- buccal nerve
Which areas are numb in long buccal nerve block?
Soft tissue on buccal side in mandibular molar region
Where is LA depot placed in long buccal nerve block?
- disto buccally of last molar in mucous membrane
Which areas are numb in a mental block?
- chin
- lower lip
- labial gingiva of/and premolars/anterior teeth
Where is LA depot placed in mental block?
- base of buccal sulcus between lower 4 and 5
Which areas are numb and where is LA placed for a supplementary lingual nerve block?
- lingual tissue
- lingual mucosa surrounding teeth to be extracted
What is the supplementary incisive nerve infiltration?
- due to cross over nerve fibres in mandibular symphysis region
- areas that are numb are buccal tissue of lower anterior teeth
- LA is placed on lingual mucosa surrounding teeth to be extracted
Which nerve do we numb for buccal infiltration for maxillary teeth?
- anterior superior alveolar nerve- incisors/canine
- middle superior alveolar nerve- premolars
- posterior superior alveolar nerve- molars
Which teeth does the nasopalatine nerve supply?
Incisors and canine
- each tooth has own branch
Which teeth does the greater palatine nerve supply?
premolars to molars
- each tooth has own branch
What should you be careful about when injecting 2nd molar palatally?
- proximity of lesser palatine nerve
- anaesthesia of soft palate if injecting distally of 2nd molar
- swallowing difficulties and great distress
What are the 3 methods for placing LA for palatal anaesthesia of maxillary teeth?
- palatal infiltration
- nasopalatine block
- greater palatine nerve block
