overview of LA techniques Flashcards
1
Q
what procedures is LA commonly used for
A
- extractions
- implants
- RCT
- restorations
- scaling
2
Q
why do we use LA
A
- would be horrendously painful if we didn’t
3
Q
what is the definition of pain
A
- an unpleasant sensory and emotional experience associated with actual or potential tissue damage
- emotional = can leave imprint on us from past experience -
4
Q
what is pain
A
- it is the body’s way of saying we are being harmed and need to do something
5
Q
what are injections referred to as in Glasgow
A
- jag
6
Q
what is the anxiety for LA often for
A
- the anxiety is often due to the needle rather than the injection itself
- need to use behavioural and physical techniques to help patient manage anxiety
7
Q
how many types of LA are there
A
- 2 types
- esters and amides
- have different chemical structures from one another
8
Q
which type of LA is more common
A
- more amides
9
Q
what can LA also help control
A
- haemostasis/bleeding which is good for surgical and restorative points of view
10
Q
what do LA also have in them
A
- vasoconstrictors = although not all of them
- adrenaline or felypressin
11
Q
what do the vasoconstrictors in LA do
A
- causes blood vessel to constrict which is advantageous as it means that the LA can stay in the area for a longer time
12
Q
what is the benefit of using adrenaline instead of felypressin
A
- adrenaline prolongs the effect of LA more than felypressin
13
Q
who can’t you use felypressin in
A
- pregnant individuals
14
Q
what can be a side effect of adrenaline
A
- can make patients feel funny
- if it has been placed in a blood vessel then the patient can get an increased heart rate as adrenaline has been sent into the blood vessel
- these patients may say they are allergic to La but they re not
15
Q
what are the two types of preservatives in LA
A
- bisulphate and propylparaben
16
Q
what can parabens cause
A
- problems with allergy
- not a true allergy though but some people may be allergic to certain ones so can’t use LA with that type in it
17
Q
how are patients with a true allergy to LA treated
A
- they will be assessed and referred to West of Scotland clinic of Glasgow Royal Infirmary
- it is really important that these patients are managed very specifically
- quite uncommon
18
Q
what are the 2 types of LA injection
A
- infiltration
- block
19
Q
what is infiltration LA
A
- local anaesthetic is deposited around the terminal branches of nerves
20
Q
what is block LA
A
- anaesthetic deposited beside the nerve trunk
- trunk of the nerve has LA deposited at it and so all fibres distal to that are blocked
- reduces pain and better for haemostat issues and good for those scared of needles
21
Q
what are infilatration LA used for
A
- used to anaesthetise soft tissues
- used to produce pulpal anaesthesia where alveolar bone is thin = maxilla and lower anterior teeth, not posterior of mandible as too thick
- most used in maxilla and anteriorly in mandible for soft tissue biopsies
22
Q
why must infiltration LA be used in thin bone areas
A
- the La needs to be able to get through the bone to get to pulps and roots of teeth sit through bone
23
Q
what is block LA used fro
A
- used to produce soft tissue anaesthesia
- used where bone is too thick for infiltration = mandible
- used when working on multiple teeth or a large area = instead of puncturing the mucosa a lot, can just do it once with this
24
Q
how do you anaesthetise the dental pulp in maxilla
A
- buccal infiltration
25
how do you anaesthetise the buccal gingiva in maxilla
- buccal infiltration
26
how do you anaesthetise the palatal gingiva in the maxilla
- palatal infiltration/injection
27
how do you anaesthetise the dental pulp in the mandible for lower molars and second premolar
- inferior alveolar Neve block (IAN)
28
how do you anaesthetise the dental pulp in the mandible for lower premolars and canines
- mental (incisive) nerve block
- depends where it is located and how many teeth it will get with the mental nerve
- can palpate for mental nerve to feel where nerve it to deposit
29
how do you anaesthetise the dental pulp in the mandible for lower canine and incisors
- buccal/labial infiltration
30
how do you anaesthetise the buccal gingiva in the lower molars and second premolar
- long buccal infiltration
| - these teeth are also supplied by the buccal nerve so need this injection as well as IAN block
31
how do you anaesthetise the buccal gingiva for lower premolar and canines
- infiltration of long buccal or mental nerve block
32
how do you anaesthetise the buccal gingiva for lower incisors and canines
- buccal/labial infiltration
33
how do you anaesthetise the lingual gingiva for mandible
- lingual infiltration
- secondary part of IAN block = when give IAN initially you are aiming for the IAN but if you withdraw 2-3mm you can also hit the lingual nerve for the tongue on that side and it is beneficial to give this injection as you only need to do it once
- sometimes for end, there is a supply to the molars from the nerve to mylohyoid so need to give that injection to
34
what tissues do you need to anaesthetise for restoration of tooth
- dental pulp as want to anaesthetise the tooth
35
what tissues do you want to anaesthetise for extraction
- pulp and gingiva
36
what tissues do you need to anaesthetise for scaling
- gingiva or pulp and gingival
| - need pulp too if root planing on dentine
37
what is he equipment to give LA
- syringe handle and bung
- syringe barrel = contains needle as well
- cartridge = can get a couple different types
38
what sizes of needles can you get
- long = 35mm
| - short = 25mm
39
what must you do when you get a cartridge
- check the expiry date and batch
| - needs to be recorded in clinical notes for traceable reasons
40
how are things packaged
- the handle and bung come together in a packet and ned to be careful when opening it as bung can fall out
- needles are packaged individually as they are single use items
41
what cartridge does lignocaine come in
- 2.2ml solution
| - 1:80,000 adrenaline
42
what cartridge does articaine come in
- 1:100,000 or 1:200,000 adrenaline
43
when do you use articaine
- has increased ability to diffuse through bone so may not need to give IAN block in mandible with this
44
when can't articaine be used
- shouldn't give IAN block with this as it can damage IAN from the needle and damage to this nerve can be life-limiting
45
what is good about articaine
- it is not processed in the liver which is good for those with liver disease
46
what is Citanest
- it doesn't contain adrenaline in it= this LA has felypressin
47
where does the needle pierce the cartridge
- the gold tips on cartridges have a little piece of non-rubber that is pierced with the needle
48
what do you do with the sticker on the packet from the equipment
- need to put in in the patients notes
49
how do you assemble the handle
- slide the chunky part onto the longer part = chunky part is where you place your fingers and loop is where your thumb goes
- put bung on with the thicker end towards the handle = if on the other way then the cartridge can get stuck in the barrel
50
how is the cartridge inserted
- insert gold end of cartridge into the needle barrel itself and press down until the little piece of plastic punctures
51
what do the safety plus syringes look like
- blue plastic shield over needle with clear plastic shield on top
52
how is the needle exposed
- take back the outer clear shield, hold the barrel with the blue end pointing away from you and pull clear shield down and clip it into the handle
- then take off blue shield and this can now be put in the bin
53
how do you ensure needle is safe before putting it down
- pull clear outer shield down to cover needle until you hear one click
- if you double click it then it becomes locker and can no longer be used
- it is good practice to only do a single click during procedures as patient may need another injection
- at the end of the procedure you need to double click and put it in sharps bin
54
why must you check patients medical history before giving LA
- for example, you cannot give haemophiliacs IAN block in routine dental practice
55
what is the position of the patient in the chair when giving LA
- usually dependant on the type of LA you are giving
- IAN often in sitting up position as can feel the anatomy better
- main justification for lying the patient back is that if the patient become hypertensive and faints then they are already lying down
56
why do you need to dry the mucosa -
- if using topical and put it on a wet mucosa then it will dilute a little and be less effective
57
how long does topical need to be applied for
- 1-2 minutes
- place a pea sized amount on cotton wool roll
- its a gel
- it gives some LA before using needle
- can either hold it on or put in on a roll and let cheek hold it in place
- good to use for infiltration LA but makes no difference for block
58
what are the 2 main types of topical
- one is minty flavoured and the other is bubblegum
59
what type of atmosphere would you want for giving LA
- tranquility
- those who are stressed are more likely to feel pain so need patient to be nice and clam and get them to focus on something else
60
how can breathing help when giving LA
- takes patients mind off of what's happening
| - focus on breathing and relaxing muscles
61
why is confidence of the dentist important
- not over confident
- if the dentist is visibly nervous then the patient can pick up on this and become more anxious as well so we need to look confident
- need to know what you are doing and how much you are going to give
62
what is the injection technique
- remove topical
- stretch mucosa
- place needle over the site you want to go
- puncture mucosa quickly = distraction for patient
- position needle tip at target point
- aspirate = safety plus system does this itself which is beneficial
- inject slowly = no less than 30 seconds, do not force it in as this will cause pain
63
how do you stretch the mucosa
- need to pull it as tight as you can
| - do with fingers initially but will eventually use a mirror so you are less likely to puncture yourself
64
what is the correct bevel orientation of the needle
- needle has bevel on it and you want the most advanced surface of the bevel facing away from the tissue
- bevel towards you during needle placement = lumen unobstructed
- incorrect = bevel facing away from you = lumen obstructed
65
what is the role of the bevel of the needle
- the role of the bevel is the provide a cutting surface that offers little resistance to mucosa as the needle penetrates and withdraws from the tissue
66
why do you want the bevel facing you
- as if the most pointy bit enter first then you are more likely to puncture the periosteum which is painful
- have most pointy part reversed
67
what is the needle position for infiltration
- bevel away from bone
- if the bevel is towards the bone, the edge of the needle is likely to penetrate the periosteum
- periosteal injections are more likely to evoke a painful response
68
what is the needle position for IAN block
- makes no statistical difference or clinical difference
69
what happens if you get blood in the cartridge after aspiration
- means you have hit a blood vessel and you need to stop and come out and change the cartridge and go back in
- aspiration is caused by pulling back on the plunger of the handle on the safety plus needles
70
how must you administer the LA
- need to drip it in
- very slowly and very gently
- it is not an opportunity to fire in as much as quickly as you can at a high volume = it is very sore for patient at high pressure and volume
71
what are some myths about LA
- needle length influences discomfort = makes no difference
- needle diameter influences discomfort
- temperature influences discomfort = some believe that if you warm it up then it makes it more comfortable but others say patients can't tell the difference between 15 and 37 degrees
72
what are some specific injections
- buccal infiltration
73
how is buccal infiltration administered
- stretch cheek = pull skin taught and identify position
- puncture mucosa with correct bevel of needle
- advance needle until over the apex of the tooth
- if contact bone, withdraw slightly
- aspirate = if negative then carry on slowly, if positive, reposition and repeat
- for molars, when doing extraction and filling, give 3/4 cartridge buccally and 1/4 palatally = some say anaesthetise roots separately on buccal or can just go in middle
- remove syringe from mouth
- slide sheath down to hear first click
- replace cartridge if need be
- massage LA into tissues
- wait for 2 mins
- test
74
how do you identify injection site
- in reflection of mucosa below apex of tooth
75
how do you replace a cartridge
- pull handle off and with it should come the cartridge and can then insert a new one
76
how do you test if LA has worked
- if removing a tooth then stick probe down the PDL
| - f doing a restoration then use a probe and check around area but don't stick down PDL
77
what are the limitations of infiltration anaesthesia
- pulpal anaesthesia limited to one or two teeth
- infection = if have infection present then won't achieve full pulpal anaesthesia, and if inject into infected area will just push infection and spread further
- dense bone = may not get anaesthesia if the bone is too dense
78
what are the positives of infiltration anaesthesia
- high success rate = works really well
- technically easy
- atraumatic
79
what are blocks used in the maxilla
- posterior superior alveolar nerve block
- middle superior alveolar nerve block
- anterior superior alveolar nerve block
- need to be aware that different parts of superior alveolar nerve supply different teeth
80
how is posterior superior alveolar nerve block given
- effective in achieving pulpal anaesthesia for the first, second and third molars
- MB on first maxillary molar is not reliable
- insert needle MB fold over maxillary 2nd molar
- upward 45 degrees to occlusal plane, inward medial toward midline 45 degrees to occlusal plane and backward direction of needle 45 degree to occlusal plane
- needle inserted around 16mm
- quite complicated
81
how is middle superior alveolar nerve block given
- advanced technique
- this nerve is only present in about 28% of population
- MB of 1st maxillary molar, premolars and canine
- MB fold over the 2nd premolar
82
how is the anterior superior alveolar nerve block given
- successful anaesthesia of maxillary incisors and canine on side of delivery
- MB fold over 1st premolar target is the infraorbital foramen
83
how do you dispose of sharps
- pull plastic up to cover needle till hear double click
- take everything apart and use sharps bins
- place needle in sharps bin = orange
- if LA cartridge is completely empty then place in orange sharps bin
- if LA cartridge has some left in it then place in blue sharps bin = but procedure on that changes
- always shut the bin over
- need to take handle apart and it goes to dirty room/box
- rubber bung is put in clinical waste as it doesn't go through sterilisation = red bin
84
what LA injections are performed as buccal infiltrations
- mental block
| - buccal injection
85
how is mental block given
- between apices of lower premolars
- do not try to put needle in foramen as could damage the nerve
- massage the LA
- this gives aneasthetic pulpally for 4321 and sometimes you can get crossover anteriorly with nerve so might need top up as could still be some innervation
86
how is buccal injection given
- lower buccal gingiva
- administer slightly distal to the tooth to be treated
- need buccal nerve block as well as IAN as its not enough alone for mandible molars
87
how is IAN block given
- need to get mouth as wide open as possible
- prepare equipment = saem as for infiltration but use 35mm needle instead
- identify site for LA
- need patient to open wide = wide stretch so it is easier to see landmarks
88
what are the important landmarks
- coronoid notch
- pterygomandibular raphe
- posterior border of mandible
- lower premolar teeth of the opposite side = barrel is going here when approaching
89
what is the position for your hand (if RH) giving IAN block
- stand in front of patient and feel the coronoid notch with left thumb and have fingers on posterior border of mandible
- thumb goes at coronoid notch of the mandibular ramus which is the greatest depression
- coronoid notch give vertical and horizontal reference points
- see pterygomandibular raphe at the midline
90
where is the site of anaesthetic deposition for IAN block
- in the region of the mandibular foramen
| - aiming for the mandibular foramen
91
what is the approach of IAN
- thumb on coronoid notch
- fingers on posterior aspect of the mandible = posterior border of the mandible is highlighted by raphe
- this positioning gives the point of puncture
- deepest point of raphe is insert point
- vertical plane is 6-10mm above lower teeth
- barrel of syringe is above premolar teeth on opposite side
92
what are the limitation if give IAN too inferior
- increased onset time
- increased lingual nerve injury
- no change in intravascular injection
- if too low, then will not get nerve numb
93
what is the injection site for IAN
- vertical position 1cm above lower teeth
- horizontal plane going 3/4 back from where thumb and raphe are is where injection goes
- keep advancing needle until you hit bone
- needle entry junction of buccal pad of fat and pterygomandibular raphe
- syringe lies over contra lateral 5 and 6
- when in correct position withdraw from bony contact slightly
- need to aspirate
94
how much of the needle should be inserted with IAN block
- 3/4 of needle should disappear into tissue
- if only 1/4 goes then you are too far anterior so need to bring barrel towards midline
- if you don't reach a bony contact then reposition syringe distally, and if too soon contact then reposition mesially
- 1cm of needle should be visible once reach bony contact
95
how do you inject the lingual nerve after IAN block
- once hit bone withdraw a couple mm to inject 3/4 of cartridge then retract 2-4mm to give lingual nerve bock where you deposit the remaining 1/4 or 1/3 of the cartridge while withdrawing
96
how should the patient feel after anaesthesia
- rubbery
- numb
- swollen/fat lips
- should reassure that is is temporary
97
what will patient still feel after IAN
- still be able to feel pressure but not pain and you should reassure them of this
98
how will patient feel after IAN block
- tongue and lower lip extending to the mid-line on that side should feel different
99
how should you test for anaesthesia if doing extraction or surgical procedure
- consider testing the mucosa with a probe to ensure anaesthesia
100
is there one way to give LA
- no, success is technique dependant
