2. Various techniques
of achieving
LOCAL
ANESTHESIA

3. LOCAL ANESTHESIA
Local anesthesia is defined as a loss of
sensation in a circumscribed area of the
body caused by a depression of excitation
in nerve ending or an inhibition of the
conduction process in peripheral nerves.
- Malamed 1980

4. Different techniques of
achieving LA
Local infiltration
Field block
Nerve block
Intraligamentry
Intraseptal
Intrapulpal
Intraosseous injection
Jet injector
Computer controlled local anesthetic delivery
system
Electronic dental anesthesia
Topical anesthesia

5. Local infiltration
In local infiltration, small terminal nerve
endings in the area of the surgery are
flooded with local anesthetic solution,
rendering them insensitive to pain or
preventing them becoming stimulated &
creating an impulse.
Incision
is made
into the same area
in which the LA has
been deposited.

6. Field block
Method of securing regional anesthesia
consisting of depositing a suitable LA
solution in proximity to the large terminal
nerve branches so that the area to be
anesthetized is circumscribed to prevent
the central passage of afferent impulses
Incision is made
into an area away
from the site of
injection

7. Nerve block
Method of securing regional anesthesia by
depositing LA solution within close
proximity to a main nerve trunk
Usually at a distance
from the site of
operative intervention

8. Periodontal ligament injection
Indications
1. Pulpal anesthesia of one
or two teeth in a quadrant
Contraindications
1. Infection or inflammation
at the site of injection
2.Treatment of isolated teeth 2. Primary teeth when the
in mandibular quadrant
permanent tooth bud is
present
3. Patient for whom residual
soft tissue anesthesia is 3. Patient who requires a
undesirable
“numb” sensation for
psychological discomfort
4. Situations in which regional
block is contraindicated

10. Intraseptal injection
Indications
When both haemostasis & pain control are
desired for soft tissue & osseous
periodontal treatment
Contraindications
Infection or severe
inflammation at the
site of injection

12. Intrapulpal injection
Deposition of LA
directly into the pulp
chamber of a pulpally
involved
tooth
provides
effective
anesthesia for pulpal
extirpation
&
instrumentation where
other techniques have
failed.

13. Intraosseous injection
Indications
Pain control for
dental
treatment
on
single
or
multiple teeth in a
quadrant
Contraindications
Infection or severe
inflammation at the
site of injection

15. Jet injector

16. Principle- based on principle that liquid forced
through very small openings, called jets, at very
high pressure can penetrate intact skin or mucous
membrane
The primary use of jet injector is to obtain topical
anesthesia before the insertion of a needle
In addition it may be used to obtain mucosal
anesthesia of palate.

17. Advantages
1. Does not require
use
of needle
2. Delivers very small
amount of LA
3. Used in lieu of
topical anesthesia
Disadvantages
1.
Is inadequate for pulpal
anesthesia or regional
anesthesia
2. May damage periodontal
tissue
3. Many patients dislike the
feeling accompanying use
of the jet injector
4. Post-injection soreness of
soft tissue may develop

18. Computer-controlled local
anesthetic delivery system
The system enables a dentist or hygienist to
accurately
manipulate
needle
placement
with
fingertip accuracy and deliver the LA with a footactivated control

20. Advantages
1. Precise control of flow rate & pressure, hence a
more comfortable injection
2. Increased tactile feel
3. Non-threatening
4. Automatic aspiration
5. Rotational insertion technique minimizes needle
deflection
Disadvantages
1.
Need for additional armamentarium
2.
Increased cost

21. Electronic Dental Anesthesia
The method of achieving local anesthesia
involves the use of the principle of
transcutaneous electrical nerve stimulation
{TENS} which has been used for the relief
of pain

22. Indications
1.
In patients with needle phobia
2.
Ineffective LA
3.
Instances where LA cannot be administered
Contraindications
1.
Cardiac pacemakers
2.
Neurological disorders
3.
Pregnancy
4.
Very young pediatric patients

25. Topical anesthesia
Anesthesia obtained by the application of a
suitable agent to an area of either the skin or
mucous membrane which it penetrates to
anesthetize superficial nerve endings
Spray
Ointments & jelly
EMLA (Eutectic mixture of LA)

27. References:Shobha tandon –Text book of pedodontics, 1st
edition 2001, published by Divyesh a kothari, page
no.464-469
Stanley F. Malamed –Handbook of local
anesthesia, fifth edition, published by Elsevier, page
no. 255-268 & 352-358
Goran koch & Sven poulsen –Pediatric dentistry
a clinical approach, 1st edition 2001, page no. 155-159
Richard R. welbury –Paediatric dentistry, second
edition, page no. 78