local anesthesia in dentistry 6 techinques

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1. Local infiltration
- type of injection that anesthetizes a small area (one
or two teeth and asscociated areas)
- anesthesia deposited at nerve terminals
1. Nerve block
- type of injection that anesthetizes a larger area
- anesthesia deposited near larger nerve trunks

 Methods:
 Reducing temperature.
 Is used only to produce surface anaesthesia e.g. ethyl chloride
spray.
 Physical damage to nerve trunk e.g. nerve sectioning.
 Unsafe for therapeutic uses, only in Trigeminal Neuralgia.
 Chemical damage to nerve trunk e.g. neurolytic agents.
 Silver nitrate, Phenol - Unsafe for therapeutic use.

 Methods: Cont
 Anoxia or hypoxia resulting in lack of oxygen to
nerve.
 Unsafe as well.
 Stimulation of large nerve fibres, blocking the
perception of smaller diameter fibres.
 includes Acupuncture and TENS (Transcutaneous
Electronic Nerve Stimulation)
 Drugs that block transmission at sensory nerve
endings or along nerve fibres.
 There action is fully reversible and without permanent
damage to the tissues.

 Classified according to their chemical structures and
the determining factor is the intermediate chain, into
two groups:
Ester Amide
 They differ in two important respect:
 Their ability to induce hypersensitivity reaction.
 Their pharmacokinetics - fate and metabolism.

 Maxillary
A. posterior superior
alveolar block
B. middle superior alveolar
block
C. anterior superior alveolar
block
D. greater palatine block
E. infraorbital block
F. nasopalatine block
 Mandibular
A. inferior alveolar block
B. buccal block
C. mental block
D. incisive block
E. Gow-Gates mandibular
nerve block

 dental procedures can usually commence after
3 – 5 minutes
 failure requires re-administration using
another method
 never re-administer using the same method
 keep in mind the total # of injections and the
dosages
 never inject into an area with an abcess, or
other type of abnormality

 Chart 9-1
 pulpal anesthesia: through anesthesia of each nerve’s dental
branches as they extend into the pulp tissue (via the apical
foramen)
 periodontal: through the interdental and interradicular branches
 palatal: soft and hard tissues of the palatal periodontium (e.g.
gingiva, periodontal ligaments, alveolar bone)
 PSA block: recommended for maxillary molar teeth and
associated buccal tissues in ONE quadrant
 MSA block: recommended for maxillary premolars and
associated buccal tissues
 ASA block: recommended for maxillary canine and the incisors in
ONE quadrant
 greater palatine block: recommended for palatal tissues distal to
the maxillary canine in ONE quadrant
 nasopalatine block: recommended for palatal tissues between the
right and left maxillary canines

 figures 9-2 through 9-7
 pulpal anesthesia of the
maxillary 3rd
, 2nd
and 1st
molars
 required for procedures
involving two or more molars
 sometimes anesthesia of the 1st
molar also required block of
the MSA nerve
 associated buccal
periodonteum overlying
these molars
 including the associated
buccal gingiva, periodontal
ligament and alveolar bone
 useful for periodontal work
on this area

 target: PSA nerve
 as it enters the maxillar through
the PSA foramen on the maxilla’s
infratemporal service – Figure 9-2
& 9-3
 into the tissues of the mucobuccal
fold at the apex of the 2nd
maxillary
molar (figures 9-4 and 9-5)
 mandible is extended toward the
side of the injection, pull the
tissues at the injection site until
taut
 needle is inserted distal and
medial to the tooth and maxilla
 depth varies from 10 to 16 mm
depending on age of patient
 no overt symptoms (e.g. no lip or
tongue involvement)
 can damage the pterygoid plexus
and maxillary artery

 limited clinical usefulness
 can be used to extend the infraorbital
block distal to the maxillary canine
 can be indicated for work on maxillary
pre-molars and mesiobuccal root of 1st
molar (Figure 9-8)
 if the MSA is absent – area is innervated
by the ASA
 blocks the pulp tissue of the 1st
and 2nd
maxillary premolars and possibly the 1st
molar + associated buccal tissues and
alveolar bone
 useful for periodontal work in this area
 to block the palatine tissues in this area
– may require a greater palatine block

 target area: MSA nerve at the apex of the
maxillary 2nd
premolar (figures 9-8 and 9-9)
 mandible extended towards injection site
 stretch the upper lip to tighten the injection site
 needle is inserted into the mucobuccal fold
 tip is located well above the apex of the 2nd
premolar
 figure 9-11
 harmless tingling or numbness of the upper lip
 overinsertion is rare

 can be considered a local
infiltration
 used in conjunction with an MSA
block
 the ASA nerve can cross the
midline of the maxilla onto the
opposite side!
 used in procedures involving the
maxillary canines and incisors and
their associated facial tissues
 pulpal and facial tissues involved –
restorative and periodontal work
 blocks the pulp tissue + the
gingiva, periodontal ligaments
and alveolar bone in that area

 target: ASA nerve at the apex of the maxillary
canine – figures 9-12 & 9-13
 at the mucobuccal fold at the apex of the
maxillary canine – figure 9-13
 harmless tingling or numbness of the upper lip
 overinsertion is rare

 anesthetizes both the MSA and
ASA
 used for anesthesia of the
maxillary premolars, canine and
incisors
 indicated when more than one
premolar or anterior teeth
 pulpal tissues – for restorative work
 facial tissues – for periodontal work
 also numbs the gingiva,
periodontal ligaments and
alveolar bone in that area
 the maxillary central incisor may
also be innervated by the
nasopalatine nerve branches

 target: union of the ASA and MSA with the IO nerve
after the IO enters the IO foramen – figure 9-15
 also anesthesizes the lower eyelid, side of nose and
upper lip
 IO foramen is gently palpated along the IO rim
 move slightly down about 10mm until you feel the depression
of the IO foramen – figure 9-16
 locate the tissues at the mucobuccal fold at the apex of the 1st
premolar
 place one finger at the IO foramen and the other on the injection site
– figure 9-17
 locate the IO foramen, retract the upper lip and pull the tissues taut
 the needle is inserted parallel to the long axis of the tooth to avoid
hitting the bone
 harmless tingling or numbness of the upper lip, side of
nose and eyelid

 used in restorative procedures that involve more than
two maxillary posterior teeth or palatal tissues distal to
the canine
 also used in periodontal work – since it blocks the
associated lingual tissues
 anesthetizes the posterior portion of the hard palate –
from the 1st
premolar to the molars and medially to the
palate midline
 does NOT provide pulpal anesthesia – may also need
to use ASA, PSA, MSA or IO blocks
 may also need to be combined with nasopalatine block

 target: GP nerve as it enters the GP
foramen
 located at the junction of the maxillary
alveolar process and the hard palate – at
the maxillary 2nd or 3rd
molar – figure 9-
19
 palpate the GP foramen – midway
between the median palatine raphe
and lingual gingival margin of the
molar tooth – figure 9-21
 can reduce discomfort by applying
pressure to the site before and during
the injection
 produces a dull ache to block pain
impulses
 also slow deposition of anesthesia will
also help
 needle is inserted at a 90 degree angle
to the palate – figure 9-22

 figure 9-23 through 9-26
 useful for anesthesia of the bilateral portion of the hard
palate
 from the mesial of the right maxillary 1st
premolar to the mesial
of the left 1st
premolar
 for palatal soft tissue anesthesia
 periodontal treatment
 required for two or more anterior maxillary teeth
 for restorative procedures or extraction of the anterior
maxillary teeth – may need an ASA or MSA block also
 blocks both right and left nerves

 target: both right and left nerves as they enter the incisive foramen
from the mucosa of the anterior hard palate – figure 9-23 & 9-25
 posterior to the incisive papilla
 injection site is lateral to the incisive papilla – figure 9-26
 head turned to the left or right
 inserted at a 45 degree angle about 6-10 mm – gently contact the
maxillary bone and withdraw about 1mm before administering
 can reduce discomfort by applying pressure to the site before and
during the injection
 produces a dull ache to block pain impulses
 also slow deposition of anesthesia will also help
 can anesthetize the labial tissues between the central incisors prior
to palatal block
 can block some branches of the nasopalatine prior to injection

3 Main Types of Maxillary Injections:
1) Local Infiltration
2) Field Block
3) Nerve Block

 Incision (treatment) is done in the same area in which
the local anesthetic was deposited (interproximal
papilla before Scaling and Root Planing)

• Local anesthetic is deposited toward larger nerve terminal
branches
• Treatment is done away from the site of local anesthetic
injection
• Maxillary injections administered above the apex of the
tooth to be treated are properly referred to as field blocks
not local infiltrations

• Local anesthetic is deposited close to a main nerve
trunk, usually at a site removed from the area of
treatment (PSA, IANB, NPB)

1) Supraperiosteal Injection
2) Intraligamentary (PDL) Injection
3) Intraseptal Injection
4) Intracrestal Injection
5) Intraosseous Injection
6) Posterior Superior Alveolar (PSA) Nerve Block
7) Middle Superior Alveolar (MSA) Nerve Block
8) Anterior Superior Alveolar (ASA) Nerve Block
9) Maxillary Nerve Block (2nd
Division)
10) Greater Palatine Nerve Block
11) Nasopalatine Nerve Block
12) Anterior Middle Superior Alveolar (AMSA) Nerve Block
13) Palatal Approach Anterior Superior Alveolar (P-ASA) Nerve
Block

The following are used in both arches:
 Supraperiosteal Injection
 Intraligamentary (PDL) Injection
 Intraseptal Injection
 Intraosseous Injection

1) Supraperiosteal Injection
 Used for pulpal anthesia in maxillary teeth
 Anesthetizes large terminal branches of the
dental plexus
 Greater than 95% success rate
 1 or 2 teeth

 Dense bone covering the apices of the teeth can lead to
failure
-maxillary molar of children (zygomatic bone
obscures)
-central incisor of adults (nasal spine obscures)
 Negligible positive aspiration rate (less than 1%)
 Should not be used for large areas (multiple sticks/large
amount of local anesthetic solution must be used)

Technique  Supraperiosteal
Injection
1) 25 or 27 gauge short needle is recommended
2) Insert needle at height of mucobuccal fold
over apex of desired tooth
3) Apply topical anesthetic for at least one
minute
4) Orient bevel toward bone; lift lip pulling
tissues taut

5) Hold syringe parallel to long axis of the tooth
being anesthetized
6) No resistance to penetration should be felt and no
patient discomfort
7) Aspirate twice
8) Deposit .6 ml (one-third of a cartridge) into tissue
over 20 seconds
9) Do not allow tissues to balloon
10) Wait 3 to 5 minutes to begin dental treatment

Problems/Failures
 If tooth does not anesthetize the needle tip could be below
the apex of the tooth resulting in inadequate anesthesia
 If the needle lies too far from the bone then anesthesia will
be inadequate because the solution was deposited in the
soft tissue (lip)
 The needle must be oriented toward the periosteum but
should be managed properly to avoid tearing the highly
innervated periosteum

These two words are used incorrectly;
what most practitioners refer to as an
infiltration injection is actually a field
block

Posterior Superior Alveolar
Nerve Block (PSA)

2) Posterior Superior Alveolar Nerve Block
 Highly successful nerve block with greater than 95%
success
 Effective for maxillary 1st
, 2nd
and 3rd
molars and buccal
periodontium
 Mesiobuccal root of the maxillary 1st
molar is not
consistently innervated by the PSA nerve

 Short dental needle is used for all but the
largest of patients
 Average depth of soft tissue penetration is 16
mm (short needle is 20 mm in length)
 28% of maxillary 1st
molars’ mesiobuccal
roots are innervated by the middle superior
alveolar nerve (MSA)

 When the risk of hemorrhage is too great as
with a hemophiliac, you should use the
supraperiosteal or PDL injections
 Patient should feel no pain with this injection
because bone is not contacted and there is a
large area of soft tissue into which the
solution is deposited

 Positive aspiration risk is 3.1%
 Patient will often say that they do not feel
numb; reason why is because they are
accustomed to the intense feeling of
anesthesia experienced by the IANB;
reassure patient that you are going to make
sure they are comfortable during the
procedure

Technique  PSA Nerve Block
1) 25 gauge short needle is recommended
2) Insert needle at the height of the mucobuccal
fold above the maxillary 2nd
molar
3) Target area is the PSA nerve which is
posterior, superior and medial to the
posterior
border of the maxilla

4) Apply topical anesthetic for at least one minute
5) Have patient open their mouth half way which
makes more room
6) Retract the patient’s cheek with mirror
7) Pull the tissues taut
8) Orient bevel toward bone

9) Insert needle at height of mucobuccal fold over the
2nd
maxillary molar
10) Advance needle upward, inward and backward
direction
11) Odd feeling of having no resistance whatsoever
12) Penetrating to an average depth of 10-14 mm is
adequate
13) Aspirate in two planes by rotating bevel one
quarter turn

14) Deposit 0.9 ml of a cartridge (1/2
cartridge)
15) Wait 3 to 5 minutes to start treatment
Advance the needle in one movement, not three
separate movements; usually atraumatic to most patients

Problems/Failures (PSA)
 Hematoma formation if needle is overinserted too far
posteriorly
 Pterygoid plexus of veins leads to this hematoma
 Visible intraoral hematoma develops within minutes;
bleeds until the pressure of the extravascular blood equals
that of the intravascular blood which can result in a large,
unsightly hematoma

 Patients will usually claim that they do not
feel any anesthesia which is not uncommon
because patients can not reach this area to
gauge their own level of anesthesia
 If using a long dental needle the maximum
insertion should be one-half on its length or
16 mm
Problems/Failures (PSA)

Middle Superior Alveolar
Nerve Block (MSA)

3) Middle Superior Alveolar Nerve Block
 Middle Superior Alveolar Nerve is not present in 28% of
the population
 When the infraorbital nerve block fails to provide
anesthesia to teeth distal to the maxillary canines, the
MSA is indicated
 MSA provides anesthesia to 1st
and 2nd
premolars and
mesiobuccal root of maxillary 1st
molar; anesthetizes
buccal periodontium and bone

 If MSA is absent the premolars and mesiobuccal root of
maxillary 1st
molar is innervated by the ASA
 Positive aspiration risk is less than 3% (negligible)
 Infraorbital nerve block can block 1st
premolar, 2nd
premolar
and mesiobuccal root of the maxillary 1st
molar if you need
an alternative block when the MSA is not adequate

Technique  MSA Nerve Block
1) 25 or 27 gauge long or short needle
2) Insert needle at the height of the mucobuccal
fold above 2nd
maxillary premolar
3) Target is the maxillary bone above the
apex of the 2nd
maxillary premolar

4) Orient bevel toward bone to avoid
tearing periosteum
5) Apply topical anesthetic for one minute
6) Pull tissues taut
7) Penetrate tissues placing bevel of needle
well above the apex of the 2nd
maxillary
premolar

Technique- Middle Superior Alveolar Nerve Block
8) Aspirate
9) Slowly deposit 0.9-1.2 ml of solution
10) Wait 3 to 5 minutes before starting
treatment

Problems/Failures MSA
 Anesthetic not deposited above the apex of
the 2nd
premolar
 Solution deposited into the soft tissue too far
from the periosteum (lip)
 Hematoma may develop; Dentist should
apply pressure to the area with gauze for at
least sixty (60) seconds; up to 2 to 3 minutes

Anterior Superior Alveolar
Nerve Block (ASA)

 Highly successful extremely safe block that
causes hesitation in most clinicians
 Provides profound pulpal and soft tissue
anesthesia from the maxillary central incisor
distal to the premolars in 72% of patients
 Used in place of the supraperiosteal injection

Uses less anesthetic solution than the supraperiosteal
injection
Supraperiosteal  3.0 ml solution
ASA  1.0 ml solution
#1 fear is damage to the patient’s eye which is
unfounded
Also known as the Infraorbital Nerve Block which is
inaccurate
Failed ASA is just a supraperiosteal injection over the
1st premolar

Areas Anesthetized  ASA Nerve Block
1) Pulp of the maxillary central incisor through the
canine
2) 72% of patients have premolars and mesiobuccal
root of 1st
molar anesthetic
3) Buccal periodontium and bone of the above teeth
4) Lower eyelid, lateral aspects of the nose and upper
lip

When Do I Use This Block?
1) Dental procedures involving more than
one tooth, i.e., central and lateral incisor
2) Inflammation/Infection precluding the use
of the supraperiosteal injection
3) Ineffective supraperiosteal injections due
to dense cortical bone

Technique  ASA Nerve Block
1) 25 gauge long needle is recommended
2) Insert needle at the height of the mucobuccal fold
over the 1st
premolar
3) Target: Infraorbital Foramen
4) Landmarks: Infraorbital Notch, Mucobuccal fold,
Infraorbital Foramen
5) Apply topical anesthetic for at least one minute

6) Feel the infraorbital notch moving your finger
down the notch palpating the tissues gently; the
outward bulge is the lower border of the orbit
which is the roof of the infraorbital foramen;
continue the finger inferiorly until a depression
is felt which is the infraorbital foramen
7) Maintain pressure over the foramen while
inserting the needle down the long axis of the
1st
premolar

8) Advance the needle slowly until bone is contacted
gently which is the upper rim of the infraorbital
foramen
9) 16 mm total advancement of needle;1/2 of long
needle length
10) Estimate the distance between the infraorbital
foramen and mucobuccal fold
11) Aspirate

12) Deposit 1.0 ml of anesthetic solution
13) Administrator can feel the anesthetic expanding
the tissue with finger tip
14) Maintain finger pressure over the foramen for
at least one minute to disperse the anesthetic
solution
15) Needle should not be palpable in most patients
16) Wait 3 to 5 minutes for anesthesia to result

Problems/Failures (ASA)
 Failure is from the needle deviating to the medial or lateral
away from the infraorbital foramen
 Failure to reach the infraorbital foramen will result in
anesthesia of the lateral side of the nose, upper lip and
lower eyelid but not the teeth
 Hematoma formation can result although rarely; apply
pressure to area for 2 to 3 minutes; at least 60 seconds

Palatal Anesthesia
 Easily one of the most traumatic experiences
for dentists due to the pain that is sometimes
elicited from the patients
 Palatal injections can be administered
atraumatically

STEPS- Results in painless palatal injections
1) Apply topical for two minutes
2) Apply pressure to site both before and
during deposition of the solution
3) Deposit solution slowly

5 PALATAL INJECTIONS
1) Anterior (Greater) Palatine Nerve Block:
no pulpal anesthesia
2) Nasopalatine Nerve Block: no pulpal anesthesia
3) Local Infiltration: no pulpal anesthesia
4) P-AMSA: pulpal and soft tissue
5) P-ASA: pulpal and soft tissue

GP Nerve Block (soft tissue and bone only)
Anesthetizes palatal soft tissue distal and
medially to the canine
(posterior portion of the palate)
Tissues around the Greater Palatine Foramen
are able to accommodate a larger volume of
solution than the tissue in the vicinity of the
Nasopalatine Foramen  less patient
discomfort

Indications for palatal injections:
1) Scaling and root planing
2) Subgingival restorations
3) Deep placed matrix bands
4) Extractions (oral surgery)

Technique  Greater Palatine Nerve Block
1) 27 gauge short needle
2) Insert needle in soft tissue slightly anterior
to the greater palatine foramen
3) Target is the greater palatine nerve as it
passes from the foramen between the soft
tissue and bone of the hard palate

Locate the Greater Palatine Foramen:
-use cotton swab/mirror handle
-place a cotton swab at the junction of the
maxillary alveolar process and the hard palate
-press firmly into tissues moving posteriorly
from the maxillary 1st
molar
-swab “falls” into the depression of the
greater palatine foramen

4) Foramen is most often located distal to the
2nd
maxillary molar
5) Apply considerable pressure to cotton swab
in area of foramen until a noticeable ischemia
occurs; hold pressure for 30 seconds before
injection

6) Continue to apply pressure throughout the
injection with the cotton swab
7) Slowly advance the needle until bone is
gently contacted
8) Depth of penetration is usually less than 10 mm
9) Aspirate
10) Deposit solution very slowly

Do not enter the greater palatine canal
There is no reason to have the needle
penetrate the canal
There is no negative repercussion except
post-operative pain

Nasopalatine Nerve Block  (soft tissue and bone only)
 Considered by many to be the most traumatic, painful
injection of all the dental injections
 Most important injection to follow the protocol about to be
explained
 Anesthetizes the anterior portion of the hard palate (soft
and hard tissues) from the mesial of the left premolar to
the mesial of the right premolar
 Use this injection for the same reasons as Greater Palatine
Nerve Block
 Target area is the incisive foramen beneath the incisive
papilla

Technique  Nasopalatine Nerve Block
2) Insertion point: palatal mucosa just lateral to the
incisive papilla
3) Approach the injection site at a 45 degree angle
4) Apply topical anesthetic for two minutes
5) Apply considerable pressure to the incisive papilla
until ischemia

6) Continue to apply pressure to the cotton applicator
tip while injecting
7) Advance the needle until bone is gently contacted
8) Depth of needle penetration is usually 5 mm
9) Slowly deposit ¼ cartridge over a 30 second
interval
10) Wait 2-3 minutes for anesthesia

There is no reason to enter the Greater
Palatine Foramen or the Nasopalatine
Foramen when providing these injections
do not advance needle more than 5 mm
into the incisive canal because it could
enter the floor of the nose causing infection

During palatal injections, the pressure
generated within the syringe will cause
the solution to spray into your mask/face;
always wear the appropriate safety
glasses and mask when giving any injection
regardless of how trivial it may seem
at the time

Technique 2nd
Example of Nasopalatine Injection
Insertion Points:
1) Labial frenum; midline of maxilla (0.3 ml over
15 seconds)
2) Interdental papilla of #8 and #9 (0.3 ml over
15 seconds)
3) Palatal soft tissues lateral to the incisal
papilla (contact bone)

Important Points:
• Topical and pressure anesthesia on the palate are not
necessary because the first injection anesthetized the
palatal
tissues
• Contact bone on the 3rd
injection (incisive papilla) only
• Interdental papilla between maxillary central incisors is
sore for a few days
• Greater palatine nerve may overlap and lead to inadequate
anesthesia of the canine and 1st
premolar

Local Infiltration of the Palate

 Anesthetizes the terminal branches of the Greater Palatine
Nerve and Nasopalatine Nerve
 Anesthetizes the soft tissue in the immediate vicinity of
the injection

Indications for Palatal Anesthesia:
1) Hemostasis during procedures of a minimal
area of tissue
2) Palatogingival pain control for rubber dam
clamps, retraction cord placement and small
surgical procedures

Important Points:
-Gate control method (inhibitory neuron prevents the
projection neuron from sending signals to the brain
(gate is closed)) of pain removal is used with
-these injections using a cotton swab for pressure
resulting in blanching tissue
-Target area is the palatal tissue 5 to 10 mm from the
free gingival margin
-Masticatory mucosa of the hard palate is only
3 to 5 mm thick
-Palatal Infiltrations are safe areas anatomically to
deposit anesthetic

P-ASA  Palatal Approach Anterior Superior Alveolar
Nerve Block
• Described in the 1990s by the inventors of the CCLAD
systems
• Comparative to the Nasopalatine Nerve Block
• Insertion: lateral point of the incisive papilla but the big
difference:
NEEDLE TIP IS POSITIONED IN THE
INCISIVE CANAL

• Deposit 1.4 – 1.8 ml of solution at
0.5 ml per minute
• Primary method of achieving bilateral
pulpal anesthesia of the maxillary
anterior six teeth; anterior palatal 1/3rd
• Provides profound soft tissue anesthesia
of the gingiva and mucoperiosteum

• Soft tissue of the facial attached gingiva
is achieved anterior to the maxillary
anterior six teeth
• P-ASA is the 1st
injection to produce
bilateral pulpal anesthesia of the
maxillary anterior six teeth from a single
injection

MAIN POINT OF THIS INJECTION:
P-ASA is designed to provide pulpal anesthesia of the
maxillary anterior six teeth in addition to the facial
gingival soft tissue and mucoperiosteum
it does not anesthetize the lip as with the regular mucobuccal
fold approach; esthetic Dentistry can then be assessed
without dealing with lip anesthesia when smiling

• Palatal approach allows anesthesia to be limited to the
subneural plexus for the maxillary anterior teeth and
nasopalatine nerve
• Minimum volume for injection is 1.8 ml (full cartridge)
over 0.5 ml/minute
• Insert needle very slowly
• 4% anesthetics should have volume reduced by ½
(Prilocaine/Articaine)

• Do not use 1:50,000 epinephrine
• May need supplemental mucobuccal fold
injections for canines because of their
very long roots
• Palatal ulcers develop from ischemia
1-2 days after treatment and are self-
limiting; healing occurs in 5-10 days

Technique  P-ASA
2) Insert needle just lateral to the incisive
papilla in the papillary groove
3) Target is the nasopalatine foramen
4) Needle held at 45 degree angle to the palate
(same as central incisors)

5) Insert needle 6 to 10 mm; if resistance is found do
not force needle
6) Insert needle 1-2 mm every 4-6 seconds while
administering solution
7) Resistance means you have to reinsert the needle;
careful of nose floor
8) Aspirate
9) Deposit 1.8 ml of anesthetic solution very slowly
0.5 ml/minute
10) Patient may feel “needle shock” very disturbing to
patient

Maxillary Nerve Block
1) Greater Palatine Approach
2) High Tuberosity Approach

 Also known as a 2nd
Division block
 Anesthetizes the maxillary division
of the trigeminal nerve

Areas Anesthetized:
1) Pulpal anesthesia of all teeth on the side of
injection (ipsalateral)
2) Buccal periodontium and bone on the side of
injection
3) Soft tissues and bone of the hard palate/soft palate
medial to midline
4) Skin of lower eyelid, side of the nose, cheek and
upper lip

 It would require 4 other injections to get the
effect of the Maxillary Nerve Block i.e.,
PSA, Infraorbital, Greater Palatine and
Nasopalatine
2 Approaches:

Technique
 25 gauge long needle recommended
 Insert into palatal soft tissue over greater palatine foramen
 Target is the maxillary nerve as it passes through the
Pterygo-palatine Fossa; the needle passes through the
Greater Palatine Canal to reach the Pterygopalatine Fossa

 Find the foramen by using a cotton swab until
it “falls into” the foramen
 Most often found at distal of the maxillary 2nd
molar
 Topical anesthetic for at least two minutes
 Inject into the area adjacent to the Greater
Palatine Foramen in order to block the nerve
before probing into the actual foramen itself

Technique
 Remember to apply constant pressure into this area until
the
tissue blanches which will lessen the discomfort of the
needle penetration
 Probe gently for the foramen with the needle tip at a
45 degree angle
 After finding the canal advance the needle 30 mm
 5 to 15% of foramens have boney obstructions, so if you
encounter an obstruction do not force the needle, try again
then abort

1) Greater Palatine Approach Complications
 Penetration of the orbit leading to a myriad of
complications
periorbital swelling or proptosis (bulging eye)
block of 6th
cranial nerve producing diplopia
(double vision)
Retrobulbar (behind the eye) hemorrhage,
corneal anesthesia
optic nerve anesthesia  loss of vision

Penetration of the nasal cavity (medial wall
of the pterygopalatine fossa is paper thin):
-patient complains of something draining
down their throat
-large amounts of air will be aspirated into
the cartridge

25 gauge long needle recommended
Insert to the height of the mucobuccal fold distal
to the 2nd
molar
Target is maxillary nerve as it passes through the
pterygopalatine fossa
Superior and medial to the target site of the PSA

Again, advance the needle to a depth of 30 mm
Upward, inward and backward direction same as
PSA
Resistance should not be felt, if it is, the
angulation is too medial
At 30 mm the needle tip should lie within the
pterygopalatine fossa
Aspirate several times and inject 1.8 ml (one
cartridge) slowly

2) High Tuberosity Approach Complications
 Hematoma develops rapidly if the maxillary
artery is punctured with the needle tip

Thin, porous substance of the maxillary bone allows for
rapid diffusion of solutions into the cancellous bone
Most Dentists rely solely on the supraperiosteal injection
to provide anesthesia in the maxilla
PSA and ASA combined can deliver safe anesthesia to
virtually all patients requiring maxillary anesthesia

Universal:
-applying topical anesthetic for
one minute
-proper patient positioning
-aspiration
-making the needle safe after each
injection with the scoop technique

 Chart 9-2
 infiltration is not as successful as maxillary anesthesia
 substantial variability in the anatomy of landmarks when
compared to the maxilla
 pulpal anesthesia: block of each nerve’s dental branches
 periodontal: through the interdental and interradicular branches
 Inferior Alveolar block: for mandibular teeth + associated lingual
tissues and for the facial tissues anterior to the mandibular 1st
molar
 Buccal block: tissues buccal to the mandibular molars
 Mental block: facial tissues anterior to the mental foramen
(mandibular premolars and anterior teeth)
 Incisive block: for teeth and facial tissue anterior to the mental
foramen
 Gow-Gates: most of the mandibular nerve
 for quadrant dentistry

 also called the mandibular block
 most commonly used in dentistry
 for restorative, extraction and periodontal
work
 pulpal anesthesia for extractions and
restorative
 lingual periodonteal anesthesia
 facial periodonteal anesthesia of anterior
mandibular teeth and premolars
 may be combined with the buccal block
 can overlap with the incisive block
 local infiltrations in the anterior area are
more successful than posterior injections
 variability in the location of the
mandibular foramen on the ramus can
lessen the success of this injection
 usually avoid bi-lateral injections since
they will completely anesthetize the entire
tongue and can affect swallowing and
speech

 target: slightly superior to the mandibular
foramen – figure 9-27
 the medial border of the ramus
 will also anesthetize the adjacent anterior
lingual nerve – figure 9-30
 injection site is found using hard
landmarks
 palpate the coronoid notch – above the 3rd
molar
 imagine a horizontal line from the coronoid
notch to the pterygomandibular fold which
covers the pterygomandibular raphe – figure
9-32
 this fold becomes more prominent as the
patient opens their mouth wider
 refer to video notes
 figure 9-33
 needle is inserted into the
pterygomandibular space until the
mandible is felt – retract about 1 mm
 average depth: 20-25mm
 diffusion of anesthesia will affect the
lingual nerve

 symptoms: harmless tingling and numbness of the
lower lip due to block of the mental nerve
 tingling and numbness of the body of the tongue and
floor of mouth – lingual nerve involvement
 complications:
 failure to penetrate enough can numb the tongue but not block
sufficiently
 lingual shock – involuntary movement as the needle passes the
lingual nerve
 transient facial paralysis – facial nerve involvement if inserted
into the deeper parotid gland – figure 9-34
 inability to close the eye and drooping of the lips on the affected side
 hematoma can occur
 some muscle soreness
 patient-inflicted trauma – lip biting etc...

 figures 9-36 and 9-37
 for buccal periodonteum of mandibular molars,
gingiva, periodontal ligament and alveolar
bone
 for restorative and periodontal work
 buccal nerve is readily located on the surface of
the tissue and not within bone

 target: buccal nerve as it passes
over the anterior border of the
ramus through the buccinator
– figure 9-36
 injection site is the buccal
tissues distal and buccal to the
most distal molar – on the
anterior border of the ramus as
it meets the body – figure 9-37
 pull the buccal tissue tight and
advance the needle until you
feel bone – only about 1 to
2mm
figure 9-38
 patient-inflicted trauma – lip
biting etc...

 figures 9-39 through 9-
41
 for facial periodonteum
of mandibular
premolars and anterior
teeth on one side
 for restorative work –
incisive block should be
considered instead

 target site: mental nerve before it enters
the mental foramen where it joins with
the incisive nerve to form the IA nerve
– figure 9-39
 palpate the foramen between the apices
of the 1st
and 2nd
premolars
 palpate it intraorally – find the
mucobuccal fold between the apices of
the 1st
and 2nd
premolars – figure 9-42
 in adults, the foramen faces
posterosuperiorly
 may be anterior or posterior
 can be found using radiographs
 insertion site is the mucobuccal fold
tissue directly over or slight anterior to
the foramen site
 avoid contact with the mandible with
the needle
 depth is 5 to 6mm
 no need to enter the foramen

 for pulp and facial tissues of the teeth anterior
to the mental foramen
 same as the mental block except pulpal anesthesia is
provided also
 restorative and periodontal work
 IA block indicated for extractions – no lingual
anesthesia with an incisive block
 target: mental foramen – figure 9-43

 injection site: figure 9-44
 same as for the mental block
 directly over or anterior to the
mental foramen
 in the mucobuccal fold at the
apices of the 1st
and 2nd
premolars
 pull the buccal tissues laterally
 more anesthesia is used for this
block when compared to the
mental block
 pressure is applied during the
injection – forces for anesthetic
solution into the foramen and
block the deeper incisive nerve
 the increased injection solution
may balloon the facial tissues

 figures 9-45 through 9-
50
 blocks the IA, mental,
incisive, lingual,
mylohyoid,
auriculotemporal and
buccal nerves – figure 9-
28 and 9-45
 used for quadrant
dentistry
 buccal and lingual soft
tissue from most distal
molar to the midline
 greater success than an
IA block

 target site: anteromedial border of the
mandibular condylar neck – figure 9-46
 just inferior to the insertion of the
lateral pterygoid muscle
 injection site is intraoral
 locate the intertragic notch and labial
commisure extraorally
 draw a line from the tragus/intertragic
notch to the labial commisure – figure 9-
47
 place your thumb on the condyle (just in
front of the tragus when the mouth is
open)
 pull buccal tissue away
 place the needle inferior to the
mesiolingual cusp of the MAXILLARY
2nd
molar
 the needle penetrates distal to the
maxillary 2nd
molar
 see the video

 MAXILLARY :
1) Supraperiosteal
2) PDL
3) Intraseptal Injection
4) Intracrestal Injection
5) Intraosseous Injection
6) PSA Nerve Block
7) MSA Nerve Block
8) ASA Nerve Block
9) Maxillary Nerve Block
10) Greater Palatine Nerve Block
11) Nasopalatine Nerve Block
12) AMSA Nerve Block
13) P-ASA Nerve Block
157

 Greater palatine
nerve block
 Nasopalatine
nerve block
161

 MANDIBULAR INJECTION
TECHNIQUES:
1) IANB Nerve block
2) Buccal Nerve Block
3) Mandibular nerve block techniques:
- Gow Gates technique
- Vazirani Akinosi closed mouth
mandibular block
4) Mental Nerve block
5) Incisive nerve block
162

169
surface anesthesia for intact skin.

 DentiPatch (lidocaine transoral delivery system)
Preinjection – 10-15 minutes exposure prior to
injection - Root scaling/planing – apply 5-10
minutes prior to beginning procedure.
170

 PRESSURE SYRINGE :
 Used in IL injection techniques,
especially in mandibular teeth (types:
pistol-grip, pen-grip).
171

local anesthesia in dentistry 6 techinques

local anesthesia in dentistry 6 techinques

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