Download Dental Nerve Blocks - The SH-ED

Dental Nerve Blocks
Editor(s): Todd W Thomsen, MD
Contributor(s): Adapted from
Section Editor(s): Gary S Setnik, MD, FACEP
PRE-PROCEDURE
INDICATIONS
Dental pain
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Dental trauma
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Incision and drainage
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Extensive wound care

Laceration repair
CONTRAINDICATIONS

Allergy to local anesthetics

Peripheral vascular, heart, and liver
disease may increase the risk of severe
complications.
EQUIPMENT

3-mL Luer-lock syringe with a 1½-inch,
25- to 27-gauge needle or Monoject
aspirating dental syringe (Kendall,
Mansfield, Mass.)
o
Use a needle no smaller than
27-gauge for deep block techniques.

Topical 20% benzocaine (HurriCaine,
Beutlich Pharmaceuticals, Waukegan, Ill) or 5%
to 10% lidocaine

Cotton swabs for application of topical
agents

2% lidocaine with a vasoconstrictor,
such as 1:100,000 or 1:50,000 epinephrine, or
other anesthetic agents with or without
vasoconstrictor agents
ANATOMY

Maxillary nerve (V2; 2nd branch of the
trigeminal nerve)
o
Posterior superior alveolar
(PSA) nerve

Supplies all the roots
of the third and second molar teeth and
two roots of the first molar tooth

Landmarks for block:
the posterolateral portion of the maxillary
tuberosity and the second molar
o
Middle superior alveolar
(MSA) nerve

Supplies the maxillary
first and second bicuspid teeth and the
mesiobuccal root of the first molar

Landmark for block:
junction between the second premolar and
first molar
o
Anterior superior alveolar
(ASA) nerve

Supplies the maxillary
central, lateral, and cuspid teeth; the labial
mucous membrane; the periosteum; and
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Figure 2 : Dental trauma.
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Figure 3 : Equipment.
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Figure 4 : Branches of the maxillary nerve.
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the alveoli on one side of the median line
Landmark for block:
the apex of the canine tooth
o
There is communication
between the ASA, MSA, and PSA nerves.

Mandibular nerve (V3; 3rd branch of
the trigeminal nerve)
o
Supplies the lower face and
temporal region, including the lower jaw and
lip
o
Inferior alveolar nerve

Descends under the
external pterygoid muscle and passes
between the ramus of the mandible and
the sphenomandibular ligament to enter
the mandibular canal, where it is
accompanied by the inferior alveolar artery
and vein

The inferior alveolar
nerve is blocked at the pterygomandibular
triangle.

Landmarks for this
block: anterior border of the ramus of the
mandible, the intraoral coronoid notch, and
the occlusal plane of the molars

Figure 5 : Inferior alveolar and lingual nerves.
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PROCEDURE
Sample excerpt does not include step-bystep text instructions for performing this
procedure
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The full content of this section includes:
Step-by-step text instructions for
performing the procedure
Clinical pearls providing practical clinical
tips from medical experts
Patient safety guidelines consistent with
Joint Commission and OHSA standards
Links to medical evidence and related
procedures
Figure 10 : Deposit 1 to 2 mL of anesthetic at
the apex of the tooth.
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Figure 13 : Needle entry occurs at the upper
second molar.
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Figure 17 : Needle entry occurs between the
second premolar and the first molar teeth.
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Figure 20 : Needle entry occurs at the apex of
the canine tooth.
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Figure 23 : Palpate the anterior border of the
ramus with your thumb, and retract the cheek
laterally.
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Figure 24 : Proper needle trajectory.
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POST-PROCEDURE
CARE
Specific follow-up for the anesthetic procedure is not needed unless there is a
complication.
Advise the patient to not eat solid foods and to avoid hot foods or aggressive wound care
until the anesthesia has worn off.
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o
o
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Avoid ischemia-producing compression dressings.
Advise the patient to follow up if signs of infection develop at the site of infiltration.
Nerve injury is rare and most cases are transient and resolve completely.
COMPLICATIONS

Complications of the inferior alveolar nerve block
o
Temporary facial nerve paralysis

Complications of the posterior superior alveolar nerve block
Puncture of the pterygoid plexus and formation of a pterygoid hematoma
If the needle is advanced too far posteriorly, a Division II block of cranial nerve V
will result.

Neuritis

Intravascular injection

Hematoma


Infection
Systemic toxicity