Maxillary Injection
Techniques
Anatomy
Anatomy
Atraumatic Injection Protocol
3 Main Types of Maxillary Injections:
1) Local Infiltration
2) Field Block
3) Nerve Block
Local Infiltration
• Incision (treatment) is done in the same area in which the
local anesthetic was deposited (interproximal papilla
before Scaling and Root Planing)
Field Block
• 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
Nerve Block
• Local anesthetic is deposited close to a main
nerve trunk, usually at a site removed from the
area of treatment (PSA, IANB, NPB)
Types of Injections
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
Maxillary and Mandibular
Injections
The following are used in both arches:
• Supraperiosteal Injection
• Intraligamentary (PDL) Injection
• Intraseptal Injection
• Intraosseous Injection
Supraperiosteal 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
Supraperiosteal Injection
 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
Supraperiosteal vs. Infiltration
These two words are used incorrectly;
what most practitioners refer to as an
infiltration injection is actually a field
block
Citing the ongoing economic crisis
and growing competition from
other insurers, Washington Dental
Service will reduce reimbursement
rates for all dental procedures by
15% starting June 1. Was it purely a
business decision?
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
Problems/Failures (PSA)
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
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
Middle Superior Alveolar Nerve
Block
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
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
Greater Palatine Nerve Block
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
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
1) 27 gauge short needle is recommended
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
Other Than P-ASA and
Maxillary Nerve Blocks
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
Back Spray
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
nd
2
Example of Nasopalatine Injection
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)
2nd Example of Nasopalatine Injection
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
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
Local Infiltration of the Palate
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
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 selflimiting; healing occurs in 5-10 days
Technique  P-ASA
1) 27 gauge short needle is recommended
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
Maxillary Nerve Block Facts
Also known as a
nd
2
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
Maxillary Nerve Block Approaches
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:
1) Greater Palatine Approach
2) High Tuberosity Approach
1) Greater Palatine Approach 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
1) Greater Palatine Approach 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
Maxillary Nerve Block Complications
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
Maxillary Nerve Block Complications
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
Maxillary Nerve Block 2nd Approach
2) High Tuberosity Approach
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
Maxillary Nerve Block 2nd Approach
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
References
Malamed, Stanley: Handbook of Local Anesthesia. 5th Edition. Mosby. 2003