Inferior alveolar nerve block is a Mandibular nerve block given to anaesthetize the Mandibular teeth, due to its proximity to other Nerves and muscles and salivary glands it has many complications if the technique in which it is given is wrong.
Complication Specific to Inferior alveolar Nerve Block:
Undesirable Never Block: Due to the proximity of the Inferior alveolar nerve block needle position to the facial nerve and the Parotid through which it passes is the result of this complication where we can see the charecteristic complications when the Facial nerve is anesthetized:
Transient Hemifacial Paralysis: In this we can see from the image below that the muscles being supplied by that side of the facial nerve are affected and cannot contract, and this results in loss of muscle action of the affected side of the face.
- Where the eye lids cannot be closed by the patient
- Loss of maintaining of lips position on the affected side and drooping of the lips on the affected side is seen in the image below.
How to manage Transient Hemifacial Paralysis due to complication of Inferior alveolar nerve block
- If this condition is ever encountered be calm and explain the patient about the problem which has occurred and assure him that it is temporary and will be back to normal in 3 hours after the effect of local anaesthesia is gone.
- Prescribe Eye drops and ask the attendant or the patient to keep putting 2 drops for every 15 mins on the affected eye to keep the eyes wet as the eye lids cannot be closed due to paralysis of the facial nerve.
- Ask the patient to use a clean cloth to keep over the eye to prevent dust from entering the open eye.
- Lastly ask the patient to stay in the clinic for 3 hours if possible to monitor the condition after the effect of local anaesthesia wears off.
The General Complications of Inferior Alveolar Nerve Block which is common with other nerve blocks:
- Muscle Trismus: It is due to muscle spasm which is caused when the injection is given into the Medial Pterygoid muscle causing tearing of the muscle fibers. It is called as Medial Pterygoid Trismus or Myospasm. Onset of Muscle trismus in inferior alveolar nerve block is after 24 hours of the injection and it resolves by itself without any treatment. In some cases anti inflammatory drugs and muscle relaxants might be required.
- Hematoma: It is also caused when there is an accidental injection to the Blood vessel which in turn leads to Hematoma formation.
- Mucosal Irritation:
- Needle Breakage:
Click here for: Comprehensive List of Complications due to Nerve Block