A dentist who gives painless treatment leaves a lasting positive impression on the patient. Most of the invasive dental procedures involves anesthetising the concerned tooth and its surrounding structures. In some procedures an entire quadrant maybe anesthetised if multiple teeth are involved.

The most common way to deliver an anesthesia is through a syringe. Depending on the severity of the treatment, the anesthetic agent can be delivered through different anatomic regions. One such technique of numbing the tooth is through intraseptal injection.

Intraseptal injection is often used as a supplementary technique. A supplementary technique is one that is used in addition to the main technique. For example, a highly infected tooth in the lower jaw might need numbing of the entire side of that jaw (main) in addition to additional deposition of the anesthesia around the concerned tooth (supplementary). A supplementary injection alone may not provide the needed anesthetic effect.

In order to numb a tooth, the tissues around the tooth need to be anesthetized by numbing the main nerve supplying them. Additionally, the nerves present in the tooth itself also need to be numbed. These are present at the core of the tooth in a soft tissue called the pulp. Obtaining pulpal anesthesia is always challenging for the dentist. Achieving pulpal anesthesia is of paramount importance.

Intraseptal dental injection technique

Intraseptal injection is more commonly employed in the lower jaw. The syringe is positioned in the triangle made by the gums between two teeth. The point of insertion is approximately 2-3 mm below the apex of the gummy triangle. It is in this region where nerve bundles can be found, the branches of which enter the tooth through the surface of the roots or from its apex.

The needle used for this technique is of 27 gauge. The needle is penetrated till the bony septum is hit and around 0.5 mL of solution is deposited. The dental surgeon will take nearly 20 seconds to entirely deposit the solution. This time is also dependent on the back pressure experienced by the dentist as the solution is injected within the bony septum. The needle is penetrated on either side of the tooth.

Once the intraseptal injection is delivered, then its action begins quickly but doesn't last as long as the dentist would want for the completion of treatment. In order to keep the tissues anesthetised for a longer period, the dentist may have to give an intraseptal injection more than once as needed.

Advantages of intraseptal anaesthesia

The advantage of intraseptal injection is that the solution spreads better through the medullary bone when it is deposited in the bony septum. The technique also doesn’t cause prolonged anesthesia. This decreases the chances of the patient biting his or her own cheek or lip. The action of the anesthesia begins faster than other techniques.

This mode of anesthesia is also helpful in achieving anesthesia in radical dental surgeries like flap surgery and periodontal grafting. Compared to other supplementary techniques, the intraseptal technique requires the least anesthetic solution in order to achieve anesthesia. Thus, it is favorable for use in patients with systemic conditions involving the cardiovascular system.

Intraseptal injection reduces the chances of post-operative complications. These include excessive blood loss, prolonged anesthesia and toxicity of local anesthetic agent. The benefits of using intraseptal injection is that not only does it numb the gums around the tooth but also the nerve endings around the roots of the tooth as well.

Compared to some other supplementary techniques, intraseptal injection does not exert any undue force on the underlying bones and ligaments. In children, intraseptal injection can be more beneficial than other techniques. This is because it does not spread or diffuse below the roots which increases the chances of the permanent tooth bud being damaged by the local anesthetic solution.

Disadvantages of intraseptal injections

This technique can be tricky to master. An inexperienced dentist may inflict multiple punctures in order to access the anesthetic point. Moreover, the anesthetic solution may leak inside the oral cavity due to which the patient may experience bitter and unpleasant taste of the anesthetic solution. A specialised syringe is needed for intraseptal anesthesia which may not be available with every dentist.

Intraseptal injections were first described in 1967 by H. W. Marthaler in France. It is today one of the modes through which pain-free dental treatment can be achieved