10 Local Anesthesia

Question 1

anesthesia onset time for IAN

Answer 1

15 minutes

Question 2

anesthesia onset time for maxillary infiltration

Answer 2

5 minutes

Question 3

least effective way to determine if a patient is numb

Answer 3

• ask patient if lip is numb

- poke gingiva with sharp instrument

Question 4

most effective way(s) to determine if patient is numb

Answer 4

-EPT, Cold tests

Question 5

which arch is more difficult to anesthetize?

Answer 5

mandibular teeth are more difficult than maxillary

Question 6

are anterior or posterior teeth more difficult to anesthetize with an IAN?

Answer 6

anterior

• first molar success 51-75%
• central incisor success: 10-50%

Question 7

what attempts to explain why anterior teeth are more difficult to anesthetize than posterior teeth for an IAN

Answer 7

the central core theory

Question 8

What are the considerations for anesthetizing a tooth with Irreversible Pulpitis?

Answer 8

-pulps are inflamed
• Inflammatory mediators reduce the excitability threshold of the nerves.
• Alteration of sodium channels decreases action of local anesthetic.

Question 9

• A normally non painful stimulus causes pain.

* A tooth with symptomatic apical periodontitis is painful to percussion

Answer 9

allodynia

Question 10

• A noxious stimulus produces more pain than it normally would
• Elevated, prolonged cold response in a tooth with irreversible pulpitis

Answer 10

hyperalgesia

Question 11

success rate for IAN Block for teeth with IP

Answer 11

15-25% success

Question 12

Pulp Testing with IP

Answer 12

• A positive cold response or <80/80 EPT will indicate lack of anesthesia.
• A negative cold response or 80/80 EPT will NOT always indicate profound anesthesia.

Question 13

Infiltration After IAN Block Mandibular Molars

Answer 13

• 4% Articaine with 1/100k Epi = 88% (58% IP)

* 2% Lidocaine with 1/100k Epi = 71%

Question 14

Infiltration Mandibular Anteriors

Answer 14

• Nuzum et al. JOE June 2010

Labial and lingual infiltrations of 4% Arti with 1/100k epi(1 carpule each) achieves 98% anesthesia (healthy pulp)

Question 15

Incisive Nerve Block at the Mental Foramen

Answer 15

Works for Premolars not Incisors

Question 16

Intraligamentary Injection success rate

Answer 16

50-96% success

Question 17

Intraosseous Anesthesia

Answer 17

• 2% Lidocaine with 1/100k Epi = 91% • 3% Mepivacaine = 80% (98% with
3.6 ml)
• 4% Articaine with 1/100k Epi = 86%

Question 18

Systemic Effects of anesthesia (intraosseous?)

Answer 18

67% had Increased Heart Rate with Epi

Question 19

what is the name of the “needle” for intraosseous injections?

Answer 19

Stabident perforator (X tip)

Question 20

The best option for achieving profound anesthesia on a tooth with irreversible pulpitis is:

Answer 20

supplemental intraosseous injection.

Question 21

Solving Maxillary Anesthesia

Problems

Answer 21

• Using an agent with vasoconstrictor will
increase duration
• Using 2 carpules of 2% Lidocaine with 1/100K will increase duration
• Articaine works better than Lidocaine for lateral incisor (not 1st molar)
• V2 block works for molars (not premolars forward)
• Infraorbital block does not work for incisors • PSA works for 2nd molars not 1st molars

Question 22

Maxillary teeth with Irreversible Pulpitis

Answer 22

12% require supplemental intraosseous anesthesia

Question 23

Considerations for Necrotic Teeth

Answer 23

• Use block anesthesia where possible • Inject around a swelling (not into it)
• Do not use intraosseous technique