To determine whether a tooth has a nerve leak, patients can take the following two methods at home on their own: 1. Drinking hot water method, the tooth that has a nerve leak will experience severe pain after drinking hot water, and the pain is usually more than a minute. Once the nerve has really leaked, the patient needs to undergo root canal treatment as soon as possible.2. Patients can be self-conscious of whether there is spontaneous pain. One of the most obvious symptoms of pulpitis is the occurrence of pain on its own without any stimulation. If there is spontaneous pain, the patient needs to undergo treatment as soon as possible. By using these two methods, patients can determine if their teeth are leaking nerves. If the tooth is only very sensitive to cold or heat or has some pain when encountering acid or sweet, but it is all transient, usually it is only deeper decay, and it can be cured by timely filling without root canal treatment.