Left cheek pain when biting may be mumps, temporomandibular joint disorder, biting myofasciitis caused by mild patients can improve in 3-7 days, the situation is serious, the recovery time is longer. 1. Mumps: the disease caused by the left cheek pain when biting, mild symptoms of the timely use of acetaminophen, aspirin and other drugs for anti-inflammatory treatment, usually 3-5 days can be improved; the relatively serious condition will take 10 days, some patients will even longer. 2. Temporomandibular joint disorder: its recovery time is also related to the condition, the treatment to ibuprofen extended-release capsules and other pain medications, during which you can also microwave, hot compresses and other physical therapy, if the situation is mild, it can be improved in about 2 weeks, and the serious ones will take 1~2 months. 3. Bite muscle fasciitis: this kind of patients will also appear in the left cheek a bite on the pain and so on, to ensure adequate rest and treatment, most patients can get better in about 1 week. The cause of left cheek pain when biting is more complex, it is recommended to use medication according to the doctor’s guidance can be improved in a short period of time.