Nerve injury is an uncommon complication associated with the extraction of wisdom teeth, or third molars. This issue arises when nerves near the surgical site are stretched, bruised, or otherwise affected during the procedure.
The resulting condition, often called paresthesia or dysesthesia, involves an altered or abnormal sensation. Patients typically experience persistent numbness, tingling, or a change in feeling across the lip, chin, or tongue.
Identifying the Specific Nerve Injury
The lower jaw contains two main sensory nerves that are most commonly affected during the removal of impacted wisdom teeth. The Inferior Alveolar Nerve (IAN) travels through the jawbone, providing sensation to the lower lip, chin, and teeth on that side of the face. Damage to the IAN results in sensory changes confined to the lower lip and chin area.
The second nerve at risk is the Lingual Nerve (LN). The LN runs close to the inner surface of the jaw and provides sensation and taste to the front two-thirds of the tongue. Injury to the LN can lead to numbness or altered taste perception on the affected side.
The mildest injury is similar to a temporary bruise or stunning of the nerve, which has the highest chance of full and rapid recovery. A moderate injury involves damage to the internal nerve fiber but leaves the protective outer sheath intact, resulting in a slower but likely recovery. The most severe injury involves a complete severance of the nerve, which almost always requires intervention to restore function.
Expectant Management and Natural Recovery Timelines
For most patients experiencing altered sensation after third molar extraction, the initial protocol involves a period of watchful waiting, known as expectant management. The majority of minor nerve injuries heal spontaneously over time without the need for aggressive treatment. The body’s natural nerve regeneration process is slow, progressing at an approximate rate of one millimeter per day.
Minor injuries, such as a temporary compression or stretching of the nerve, often resolve quickly, with sensation returning gradually within a few days to a few weeks following the surgery. The first critical timeframe for improvement is typically the six-to-eight-week mark, during which many patients with mild injuries see significant resolution of their symptoms. Patients with moderate injuries, where the internal structure is damaged but the outer layer remains, may require a longer period of up to six months for maximum natural recovery.
During follow-up appointments, the surgeon performs sensory testing to map the exact area of altered sensation and track changes. Documenting symptoms, such as keeping a log of the affected area’s size or the type of sensation experienced, is beneficial for tracking subtle improvements. Signs of healing often include a return of a tingling sensation, sometimes described as pins and needles, or a noticeable shrinking of the numb area. The presence of any sensation, even an unpleasant one, indicates that the nerve pathway remains partially functional.
Referral and Advanced Treatment Protocols
If altered sensation persists without improvement beyond two to three months, the injury is considered persistent, and a referral to a specialist is necessary. These specialists are typically an Oral and Maxillofacial Surgeon with microsurgical expertise or a Neurosurgeon. Advanced imaging, such as Cone Beam Computed Tomography (CBCT) or Magnetic Resonance Imaging (MRI), is used to evaluate the nerve’s integrity and determine the precise location and extent of the damage.
Before considering surgery, pharmacological options are used to manage symptoms and support nerve health. Anticonvulsant medications, such as gabapentin or pregabalin, are prescribed to manage the shooting or burning pain that accompanies nerve healing. A short course of corticosteroids is also used early on to reduce localized inflammation that could be compressing the nerve.
For severe, persistent injuries, specialized microsurgical nerve repair is the next step. These procedures include neurolysis, which involves carefully releasing the nerve from constricting scar tissue, or nerve grafting. Grafting uses a segment of nerve from another part of the body to bridge a gap in a severed nerve. The timing of surgical intervention is time-sensitive, with the best outcomes achieved when the repair is performed within three to nine months of the initial injury. Delaying surgery beyond this window reduces the chances of a successful functional recovery.