Injury to the lingual nerve (LN) is a common result from Dental Malpractice. A number of oral and maxillofacial surgical procedures result in damage to the Trigeminal Nerve, Lingual Nerve or Inferior Alveolar Nerve. The most common signs or symptoms of dental nerve damage is numbness (about half) followed by numbness with pain (about 40%). Other signs of dental nerve injury are hyper-sensitivity to stimulation, a crawling feeling in the lip or chin area, burning, stinging or other altered sensation to the lip, chin and gums (for inferior alveolar nerve injuries) and a change in taste, a heavy-feeling tongue coupled with difficulties talking as normal, and/or a lack of appetite. Still other changed sensations following dental nerve injury include shooting pains in your mouth, the feeling that your tongue is burning, aching, extreme sensitivity and pain when exposed to cold, an inability to taste foods and a “pins and needles” feeling when eating.
Just like other nerve injuries, dental nerve injuries are classified by the degree of injury. The timing and success of the nerve repair depends on the extent of injury. Clinically useful injury grading systems have been developed that allow correlation of the microscopic changes occurring after nerve injury and patient symptoms. Perhaps the most widely accepted are those developed by Seddon and Sunderland. Seddon divided nerve injuries by severity into three broad categories: neurapraxia, axonotmesis, and neurotmesis. Neurapraxia, the mildest injury type, does not involve loss of nerve continuity and causes functional loss, which is transient. This symptom’s transience it thought to be due to a local ion-induced conduction block at the injury site, although subtle alterations in myelin structure have also been found. Axonotmesis occurs when there is complete interruption of the nerve axon and surrounding myelin while the surrounding mesenchymal structures including the perineurium and epineurium, are preserved. Axon and myelin degeneration occur distal to the point of injury, causing complete denervation. The prospect of recovery is excellent in such injuries because of the remaining uninjured mesenchymal latticework that provides a path for subsequent sprouting axons to reinnervate their target organ. Neurotmesis involves disconnection of a nerve. Functional loss is complete and recovery without surgical intervention, does not usually occur because of scar formation and the loss of the mesenchymal guide that properly directs axonal re-growth.
Sunderland’s classification system further stratifies the three injury types described by Seddon into five categories according to severity. A first-degree injury is equivalent to Seddon’s neurapraxia and a second-degree injury is equivalent to axonotmesis. Third-degree nerve injuries occur when there is disruption of the axon (axonotmesis) and also partial injury to the endoneurium. This categorization places a third-degree between Seddon’s axonotmesis and neurotmesis. Dependent on the extent of the endoneurial damage, functional recovery may be possible. Sunderland divides Seddon’s neurotmesis into fourth and fifth degrees. In a fourth-degree injury, all portions of the nerve are disrupted except the epineurium. Recovery is not possible without surgical intervention. Similarly, a fifth-degree injury involves complete severance of the nerve.
If you have suffered from a dental nerve injury, it is important to seek medical intervention as soon as possible. The longer your symptoms last, the less likely it is that you will regain full sensation in the affected areas of your mouth. Regardless of what you have been told, there are courses of treatment that can help you regain the feeling in your mouth, tongue, cheek and gums.
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