Tooth extraction is a common procedure. While generally safe, it carries a small, documented risk of nerve injury, especially when removing lower back teeth. This risk is primarily associated with complex extractions, such as deeply impacted wisdom teeth. Understanding how this rare complication occurs, recognizing the signs of nerve involvement, and knowing the available recovery options can help patients navigate the process.
How Extraction Procedures Affect Nearby Nerves
The possibility of nerve injury stems from the close physical relationship between the tooth roots and two major sensory nerves in the lower jaw. The Inferior Alveolar Nerve (IAN) travels through a bony channel within the jawbone, directly beneath the roots of the lower molars and wisdom teeth. This nerve provides sensation to the lower teeth, the lower lip, and the chin.
The Lingual Nerve (LN) is also at risk because it travels close to the inner surface of the jawbone, near the lower wisdom teeth. The LN supplies sensation and taste to the front two-thirds of the tongue. The proximity of the roots to these nerves means they can be disturbed or injured during the procedure.
Nerve damage can happen through several mechanisms. Direct trauma from surgical instruments, such as drills or elevators, can cause a contusion or crush injury. Stretching or compression may occur as the tooth is manipulated and removed. In some instances, the local anesthetic injection itself may cause chemical or mechanical trauma to the nerve tissue.
Identifying Symptoms of Nerve Injury
When a nerve is injured, the patient experiences sensory changes that extend beyond the normal post-operative numbness from the local anesthetic. These symptoms are purely sensory and do not affect muscle movement. The most common change is Paresthesia, characterized by a persistent feeling of numbness or a “pins-and-needles” sensation.
This numbness typically manifests in the area supplied by the injured nerve. For example, the lower lip and chin are affected if the IAN is injured, or the tongue if the LN is involved. A different type of sensation, called Dysesthesia, may also occur, involving abnormal, unpleasant, or painful feelings. Patients might report a burning or electric shock-like feeling, or that normal touch feels bizarre.
These sensory disturbances are a concern if they persist after the local anesthetic has worn off. While mild tingling can be part of the nerve’s healing process, any significant or persisting change in sensation should be promptly evaluated by the oral surgeon. Early recognition is important for proper monitoring and management.
Prognosis and Treatment Options
The outlook for most nerve injuries following tooth extraction is positive, as the majority of cases involve temporary damage like bruising or stretching, known as neuropraxia. These minor injuries often resolve spontaneously as the nerve fibers heal themselves, typically over a period of weeks or a few months. Full recovery of sensation can take anywhere from three to six months.
Initial management of a suspected nerve injury involves careful observation and regular neurosensory testing to track the patient’s progress. If the sensory changes persist, the surgeon may recommend specific medications to support nerve healing or manage discomfort. This can include anti-inflammatory drugs to reduce swelling around the nerve, or nerve-specific medications that help regulate pain signals.
For rare instances where sensory deficits remain severe and show no improvement after several months, specialized intervention may be considered. Referral to a microsurgeon who focuses on nerve repair is an option for persistent cases. Surgical repair is often recommended within an optimal window, typically between two and six months following the injury. This procedure aims to reconnect or reconstruct the damaged nerve to encourage the regeneration of sensation.