LA techniques Flashcards
What are the 5 steps in insuring a good injection technique?
-stretch mucosa -position needle tip at target point -puncture mucosa quickly (use distraction) -aspirate -inject slowly
How long should you inject LA for?
No less than 30 seconds
At the point/tip of the needle, what happens to the diameter of it?
It becomes thinner (and bevelled)
What is the role of the bevel on the needle?
To provide a cutting surface that offers little resistance to mucosa as the needle penetrates and withdraws from the tissue
Describe the bevel orientation you want to have during needle placement.
Want the bevel towards you during needle placement
Where do you want the bevel to be during an infiltration ?
-bevel away from the bone
Why do you want the bevel of the needle to be away from the bone during infiltration injections?
Because 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
How should the needle be positioned in an ID block?
Makes no statistical or clinical difference
What are some myths about LA regarding the needle length, diameter and temp?
-needle length influences discomfort (it doesn’t) -needle diameter influences discomfort -people think warm temp of needle will be more comfortable (P cannot detect if between 15 and 37 degrees)
How do you identify the injection site in a buccal infiltration?
Identify injection site in the reflection of mucosa below apex of the tooth You want to inject slightly distally to the target tooth
What kind of anaesthesia do you get with infiltration anaesthesia ? (describe how much is anaesthetised also)
-pulpal anaesthesia limited to one or 2 teeth -also get associated soft tissue anaesthesia
What are the limitations of infiltration anaesthesia?
-If inject into infection then this could cause further spread of the infection - the LA needs to diffuse through dense bone meaning that you may not get full anaesthesia
What are the advantages/positives of infiltration anaesthesia?
-high success rate -technically easy -atraumatic to tissues
Describe the technique for buccal infiltration.
-stretch cheek -puncture mucosa with correct bevel of needle -advance needle until over the apex of the tooth -if contact bone, withdraw slightly -aspirate -if negative aspiration the inject slowly
After injecting the LA in a buccal infiltration. What are the next 5 steps?
-remove syringe from mouth -slide sheath down to first click -massage the LA into tissues -wait 2 mins for anaesthesia -test to see if the area is sufficiently anaesthetised
What LA injections are performed as buccal infiltration?
-mental block -buccal injections
Where is the injection site for a mental nerve block?
Between the apices of the lower premolars
Where should you NOT try to put the need while performing a mental nerve block ? Why?
In the mental foramen - can damage the nerve
What needle size is used for an ID block?
35mm needle
What are the 4 important landmarks for an IDB block?
-coronoid notch of the mandibular ramus -posterior border of the mandible -pterygomandibular raphe -lower premolar teeth of the opposite side
Describe the hand positioning for an inferior alveolar nerve block.
Thumb goes on the cornoid process and fingers externally on the posterior border of the mandible
Why are the opposite premolar teeth an important landmark?
because this is where the barrel of the needle is going to go
The site of anaesthetic depositions in an IDB block is what region?
Region of the mandibular foramen
What are the limitation if the IDB block is delivered too inferiorally?
-increased onset time -increased lingual nerve injury
What are the steps in delivering an inferior alveolar nerve block?
-thumb placed at anterior notch -needle entry at buccal fat/pterygomandibular raphe -advance to bony contact - withdraw from bony contact and aspirate -inject slowly
What do you do if get no bony contact?
Re-position syringe distally
What do you do if you get bony contact too soon?
Resposition syringe barrel mesially
How do you confirm anaesthesia?
-Ask the patient how it feels (should feel rubbery, numb, tingly, swollen/fat BUT ability to sense pressure remains) -can test mucosa with probe if carrying out extraction or oral surgery
Where should feel numb etc in an IDB block?
-Tongue and lower lip extending to the mid-line
