Local Anaesthesia (Mandibular)

Question 1

What are the landmarks for ID block?

Answer 1

a. Coronoid notch
b. External oblique ridge
c. Internal oblique ridge
d. Pterygomandibular raphe
e. Retromolar Triangle
f. 1cm above occlusal plane

Question 2

Once the site is identified for an ID block what should be done?

Answer 2

a. Retract soft tissues on LHS with finger/mirror
b. Unsheathe needle
c. Approach from the contralateral premolars
d. Parallel to the occlusal plane
e. Insert into tissues lateral to Pterygomandibular raphe
f. Make bony contact
g. Withdraw slightly
h. Aspirate–to check that not injecting into a blood vessel
i. Inject solution slowly, to aid patient comfort
j. Inject 3⁄4 of the cartridge
k. Continuing injecting slowly on retraction of the needle–to anaesthetise lingual nerve

Question 3

What Cranial Nerve is being anaesthetised in ID block?

Answer 3

Trigeminal nerve (cranial nerve 5)

Question 4

What branch of the trigeminal nerve is being anaesthetised in ID block?

Answer 4

3rd branch

Question 5

What does an ID block anaesthatise?

Answer 5

• mandibular teeth on that side
• buccal gingivae from premolars to midline
• lingual gingivae on that side (including tongue)
• lower lip
• chin