Infraorbital nerve block techniques (Intra oral and extra oral)

Infraorbital nerve block is one of the ways that is used to anesthetize the anterior and middle superior alveolar nerves together.

Terminal branches of infraorbital nerve

• Inferior palpebral
• Lateral Nasal
• Superior labial

Nerves to be anesthetized

1. Anterior Superior Alveolar nerve
2. Middle Superior Alveolar nerve
3. Infraorbital nerves and it's terminal branches.

Anatomical landmarks

• Infra-orbital ridge
• Infra-orbital depression
• Supra-orbital notch
• Anterior teeth

Techniques to anesthetize infraorbital nerve

1. Bicuspid approach (Intra-oral approach)
2. Incisor approach (Intra-oral approach).
3. Extra oral approach

1- Bicuspid approach

• The patient in a position so that maxillary occlusal plane forms 45 degree with the floor.
• The infraorbital foramen can be located by asking the patient to look straight ahead and you imagine a line drown from the pupil of the eye to the inferior border of the infraorbital ridge passing by upper second premolar teeth.
• Locate the inferior orbital rim with your index and middle fingers of the non-injecting hand.
• Retract the patient's cheek by your thumb of the non injecting hand. e.g. the left thumb of the right handed person.
• Insert the need in the buccal mucosa opposite to upper second premolar approximately 0.5 cm from the buccal surface.
• The needle should be parallel to the Maxillary second premolar (bicuspid) and should be directed in a superior direction, until it is palpated near the foramen.
• You have to aspirate to ensure the needle is not within a blood vessel.
• You must avoid injecting the anesthetic solution into the foramen by keeping firm pressure on the infra orbital rim with your palpating finger.

2- central incisor approach

• The same as the previous method except the needle is directed to buccal mucosa in a direction mesial to incisal part of upper central and distal to cervical part of tooth.
• The needle is injected slowly in an upward, inward and backward direction.
• The bevel is kept facing the bone.

3- Extra-oral approach

• The infraorbital foramen can be located by asking the patient to look straight ahead and you imagine a line drown from the pupil of the eye to the inferior border of the infraorbital ridge passing by upper second premolar teeth.
• Locate the inferior orbital rim with your index and middle fingers of the non-injecting hand.
• Clean the skin over the infraorbital foramen by gauze and antiseptic agent as betadine.
• You have to aspirate to ensure the needle is not within a blood vessel.
• Insert the needle through the skin, subcutaneous tissue and then the muscle.
• You have to take care while giving infraorbital nerve block by extra oral approach Due to the proximity of the facial nerve.
• After removing the needle, massage the area for 10 to 15 seconds.

Complications of infraorbital nerve block

• Bleeding
• Hematoma
• Injury to the artery or vein.
• Infection
• Edema
• Facial nerve injury.
• Allergic reaction to the anesthetic solution.

Anesthetic solution that is used for infraorbital nerve block

- The most common anesthetic agents used in that case are Lidocaine and bupivacaine.

- It has been reported that Lidocaine starts to take effect after 2 to 3 minutes, while the bupivacaine can take upt to 10 to 20 minutes to take effect.

Video illustrates infraorbital nerve block technique