When a baby has fever and teeth clenching symptoms, the following two factors are usually considered: 1. The fever causes high fever convulsions and teeth clenching symptoms, the baby’s neurological development is not perfect, when the high fever will lead to abnormal excitation of the baby’s brain nerves, abnormal discharge and cause convulsions, so there will be teeth clenching and even rolling eyes, etc. 2. The baby’s fever is caused by encephalitis, meningitis and other central nervous system infections, which can trigger the baby to clench his teeth, foam at the mouth, roll his eyes and other epileptic symptoms. Once you find that your baby has a fever with teeth clenching symptoms, you need to take immediate first aid measures, to immediately cool the baby, you can take ibuprofen pellets to lower the temperature, after the symptoms are relieved you should immediately send the baby to the hospital for treatment.