Nasopalatine nerve block Technique – Local Anesthesia

Nasopalatine nerve block: Used to block the nasopalatine nerve. This is used to provide anesthesia to the Soft tissue of the Palatal aspect from the Canine to Canine.

It is anesthetized as it emerges from the anterior palatine foramen located on the anterior palate region just behind the central incisors. Let us look in detail at “How to give NasoPalatine Nerve Block” and what are the symptoms and complications seen in it.

Areas anesthetized:

• The anterior portion of the hard palate
• Overlying structures like soft tissue from the incisors to the bicuspid area
• The branches of the Anterior palatine nerve coursing distally create a dual innervation

Nerves anesthetized:

The nasopalatine nerve is the targeted nerve during its path as it emerges from the anterior palatine foramen which is located on the anterior palate in the midline of the palate.

Anatomical landmarks:

These are useful in determining the precise location of the injection site. Follow the landmarks mentioned and the location of the injection site can be determined.

• Maxillary Central Incisor teeth
• Incisive papilla in the midline of the hard palate
• Location posterior to the middle of maxillary central incisors

Indications

• For obtaining palatal anesthesia
• It cannot be used as a separate Nerve block but is used as a supplement the anterior and middle superior alveolar nerves
• It is useful in obtaining analgesia to the six maxillary incisors
• Analgesia to the Nasal septum

Image Source: K. Carter

Technique:

The Nasopalatine nerve block is given to anesthetize the nasopalatine nerve as it emerges from the anterior palatine foramen. So the first step would be to correctly identify the location of the anterior palatine foramen. This is a very painful injection due to the fact that the tissue on top of the foramen is thin and firm (hard palate) and the needle directly pierces the nerve. To keep the pain in control a preparatory injection is advised.

Preparatory injection for Nasopalatine nerve block: A small amount of 0.25 ml of anesthetic solution has to be deposited into the tissue between the maxillary central incisors. A 1-inch, 25 gauge needle has to be inserted at a right angle to the labial inclination into the labial tissue between the central incisors until you touch the bone. Now deposit the 0.25ml of anesthetic solution and withdraw the needle slowly. Local Anesthesia spray or gel can be applied on the incisive papilla, to decrease pain while inserting the needle through the papilla.

Now that the preparatory injection for Nasopalatine nerve block is done, slowly re insert the needle into the interdental papilla, while keeping the needle in line with the labial alveolar plate as seen in the image. This directs the needle into the incisive foramen. Now extend the needle just 0.5cm into the canal and deposit about 0.25 to 0.5ml of solution. Make sure that the solution is deposited very slowly, as injection site is hard palate rapid deposition of solution might lead to distension of the tissue.

This injection will produce a small area of surface anesthesia through which the Needle can be introduced painlessly to anesthetize the nasopalatine nerve. A properly made nasopalatine nerve block will anesthetize the palatal tissues of six anterior teeth. It is believed that complete anesthesia can be achieved to all the six anterior teeth if needle is carried far enough into the canal, but it is contradictory as the nerve supply to the anterior teeth is different.

Symptoms of anesthesia:

There are always two types of symptoms which should be checked to determine the success of the Nerve block given.

Subjective symptoms:
These are the symptoms which are felt by the patient which they are able to convey.

• Feeling of numbness in palate when contacted with tongue.

Objective symptoms:

These are the symptoms which are induced by the dentist to determine the success of the anesthetic injection. Usually, instruments like the Elevator are used to probe the region which has to be anesthetized to confirm the success of the anesthetic injection.

• Instrumentation is done in the anterior palate region to check if the patient feels any pain

This is the most used and easiest way to get a successful Nasopalatine Nerve Block.