The tongue is an important element of the human body and it has many functions. Among other tasks, the tongue helps to clean the mouth, it enables us to speak; it also gives us a sense of taste. One of the most vital components of the tongue is the lingual nerve.
Function of the Lingual Nerve?
The lingual nerve is responsible for the senses in the tongue. It is located near the sides of the tongue. The lingual nerve branches off the mandibular nerve and transmits taste to the brain.
The lingual nerve supplies the front two thirds of the tongue. When you eat or drink something, the nerve picks up taste information and sends it to the brain via a branch of the facial nerve. The information is then sent back to the majority of the tongue, allowing you to taste the food.
Location of the Lingual Nerve
The lingual nerve begins under the lateral pterygoid muscle (a muscle of mastication) in front of the inferior alveolar nerve. The nerve then joins up with a section of the facial nerve. It then runs past the medial pterygoid muscle and mandible (jaw) and crosses to the side of the tongue.
The lingual nerve then passes under the constrictor pharyngis superior (a muscle in the pharynx). The nerve continues to run between the hyoglossus and the submandibular gland (salivary gland). It ends beneath the tongue’s mucous membrane.
Lingual Nerve Injuries
It is unlikely that the lingual nerve will become damaged naturally, due to its protected location. Normal mouth movements, such as talking, yawning or eating food, will have no detrimental effects on the nerve. Most lingual nerve injuries occur after an oral surgical procedure has been carried out.
Various operations can injure the lingual nerve. This will result in pain or numbness, and a loss of senses. A loss of taste is the most common symptom which is likely to affect the individual’s quality of life. Most lingual nerve injuries due to surgery are temporary. However, in a small proportion of incidents, the damage will be permanent.
Conditions such as trauma, infection and autoimmune disorders can also damage the lingual nerve. Some of the more invasive cancer treatments are also harmful to healthy nerves and lead to symptoms developing.
Damage to the lingual nerve could cause a condition known as Glossodynia. A typical symptom is a burning sensation on the surface of the tongue. Surgery may be required to rectify this condition if caused by nerve damage.
Symptoms of a lingual nerve injury include:
- Numbness of the tongue
- Mouth pain
- Loss of taste
- Problems with speech
- Burning cheeks or tongue
- Decreased salivation
Dental surgery can injure the lingual nerve because the nerve passes under some of the teeth. Any kind of invasive oral surgery could damage the lingual nerve, leading to a loss of taste. Third molar or wisdom tooth extraction is the most common cause of a lingual nerve injury.
Extracting the wisdom teeth can be very difficult and, in some cases, the procedure goes wrong. When a tooth is extracted, pressure is put on the nerves and the soft tissue in and around the tooth which is being taken out. This pressure can damage the nerves, which will then lead to complications.
A dentist will sometimes have to cut around a tooth to extract it. This action is also likely to damage soft tissue and nerves. If the dentist does have to make a deep incision and the lingual nerve becomes severed, it will, or should, be repaired right away.
Invasive injections, such as local anesthetics used by surgeons and dentists, can also injure the lingual nerve. In order for the anesthetic to work, the injection has to be deep, which can damage soft tissue. In rare cases, the injection can hit the lingual nerve and cause an injury.
The lingual nerve is also at risk of being damaged when patients are having dental implants inserted. The injections, preparation of the jaw, incisions and post surgical swelling can all affect the nerves in the mouth. The way the implants are fitted can also cause some damage to the lingual nerve.
A tonsillectomy (removal of the tonsils) is a routine procedure carried out by surgeons. The lower part of the tonsil is next to the tongue; therefore, this makes the lingual nerve vulnerable during the surgical procedure. In rare cases, the surgery can injure the lingual nerve, leading to taste distortion.
Another reason the lingual nerve becomes damaged during a tonsillectomy is that during the surgery, the patient’s tongue is depressed. The surgeon needs to keep the tongue out of the way to remove the tonsils. This prolonged tongue depression can damage the lingual nerve and surrounding tissue.
Orthognathic (lower jaw) surgery can also damage the lingual nerve and surrounding tissue. During a cosmetic procedure to alter a jawline, the jaw may have to be fractured by the surgeon in order to move it. If the fracture is close to the location of the lingual nerve, there is a risk that it will be damaged.
Cancer treatments, such as chemotherapy and radiotherapy, have many side effects. One of these side effects is nerve damage due to the cocktail of drugs used for chemotherapy. The drugs used for chemotherapy are designed to attack cancer cells, but healthy cells can also be affected.
Radiotherapy targets cancer cells with high energy x-rays. This acts to slow down the effects of the disease or shrink a tumor. Unfortunately, these x-rays are also harmful to healthy cells and soft tissue. Although radiotherapy is targeted at a specific area on the body, the rays can damage nearby nerves.
A broken jaw or heavy impact in and around the area can lead to lingual nerve damage. The shock of a heavy blow can disturb the lingual nerve and a fracture or break can lead to a tear or break in the nerve. A heavy impact to the jaw can also dislodge a tooth, which could subsequently injure the lingual nerve.
Bacteria and viruses can attack healthy nerve tissue and result in damage to the lingual nerve, among others. Herpes and varicella-zoster, the virus that causes chickenpox and shingles, are known to attack healthy sensory nerves. Lyme disease, which is transmitted by ticks, also leads to nerve damage if left untreated.
People affected by HIV or AIDS are at risk of nerve damage which can affect the senses, including the lingual nerve. Lupus and arthritis cause inflammation which impacts on nerves throughout the human body.
Is Lingual Nerve Damage Permanent?
When the lingual nerve has been damaged it will usually repair itself over a period of time. It takes six to twelve weeks for nerves to repair; they generally grow at a rate of 1mm per day. However, if symptoms last for more than six months, the injury is probably permanent and untreatable.
It’s worth noting that, even if the lingual nerve repairs itself, your sense of taste can still be affected. A nerve that is repaired will never fully recover; it will still remain weak and be prone to further injury.
Are There Any Treatments for Lingual Nerve Damage?
If the lingual nerve has been damaged during a surgical procedure, there are some treatments available. Laser surgery can be used to restore some of the taste that has been lost due to the nerve damage. Not all patients will benefit from laser surgery, although a clinical study has concluded that it is successful in many cases.
Microsurgery is also effective in repairing damaged nerves; surgical advancements in the field are being made all the time. Surgeons can now stretch the two ends of a damaged nerve and join them up. The nerve will then knit together and become stronger over a short period of time.
If the lingual nerve is too badly damaged the surgeon may decide that a nerve graft is the best course of action. A donor nerve is used to connect the two ends of damaged nerve. The nerve graft promotes good healing and the nerve will begin to regrow naturally around the graft.
Vitamins have also been used to successfully treat nerve damage. Increasing the amount of vitamin B in your diet may help recovery. Vitamins B6 and BA12 are essential ingredients for building and maintaining healthy nerves. Boosting vitamin levels is not a guaranteed treatment but it does help some patients with nerve damage.
Now you have more information about the lingual nerve. You know what it does, where it is located and how it can become injured. We also told you some of the ways that the lingual nerve can be repaired after it has been damaged.