If you have the experience of going to the dentist, you know that the nerve of the tooth is highly sensitive. Therefore, until the anesthesia is completely done, the person will feel a lot of pain during the treatment. Having said that, it must be said that dental anesthesia is a specialized matter that many dentists do not have this skill. For this reason, a person endures a lot of pain during surgery. But in order to get to know the main causes of tooth numbness, follow us until the end of this article on the website of Dr. Najmeh Tadredaranjad, **Orthodontist in Mashhad**. **Incorrect injection or low anesthetic dose** If the anesthetic is not injected correctly in the desired area or if the amount is not enough, the tooth may not be completely numbed. Some parts of the mouth, such as the lower teeth, need more precision in the injection, because the nerves are deeper and harder to access. **Presence of severe infection or inflammation** If there is infection or inflammation around the tooth, the acidic environment of the injection site can reduce the effect of the anesthetic. This condition is usually seen in dental abscesses and causes anesthesia to not work well. **Anatomical differences of the individual** In some people, the path of the nerves is different than normal or the nerves are deeper. This causes the anesthetic to not reach the desired area well and the tooth is not completely numb. **Read more" The cause of protruding jaw bone after tooth extraction + treatment methods** **Nervous resistance or high anxiety** Some people are naturally resistant to anesthesia or have too much anxiety and stress that irritates the nervous system. In this case, the body responds less to the drug and the anesthesia may be incomplete. ** Read more » What is dental flooring? + Review benefits, procedures, care and costs** **Consumption of certain medications or special medical conditions:** Medications such as antidepressants or certain neurological problems can reduce the effectiveness of anesthesia. In this case, the dentist may need to change the technique or drug dosage. **Types of dental anesthetic drugs:** Dental anesthetics are usually divided into two categories: lidocaine and articaine. Lidocaine is one of the most common drugs that has a fast and appropriate effect. Articaine also has a higher penetrating power and is used for deeper anesthesia. Other drugs include mepivacaine and prilocaine. The choice of medicine is based on the type of treatment, the location of the tooth and the physical condition of the patient. **Methods of dental anesthesia:** Dental anesthesia can be done in a variety of ways, including direct injection into the gums, local anesthesia with a spray or gel, and in certain cases mandibular nerve anesthesia (nerve block). Some treatments may require regional anesthesia. According to the type of treatment and the condition of the patient, the doctor chooses the most suitable method to minimize the pain during the treatment. **Read more" in order to get to know the causes and treatment methods of tooth cracks, click on the given link.** **What is dental anesthetic gel?** Dental anesthetic gel is a topical substance that is used before anesthesia injection. This gel usually contains lidocaine or benzocaine and is used to reduce the initial pain of the needle. Anesthetic gel is also used for children or adults with high anxiety. Using it makes the injection easier and the patient feels less pain. **How to achieve complete tooth anesthesia?** To achieve complete anesthesia of the tooth, the right drug must be injected in the exact place and given enough time for its effect. Sometimes it is necessary to re-inject or use a stronger drug such as articaine. Infection or inflammation can prevent complete anesthesia. Adhering to proper technique and patient cooperation play an important role in the effectiveness of anesthesia. **Read more" What are the reasons for the need for oral and dental radiology?** **Consequences of using anesthesia ampoule:** The use of anesthesia ampoule is usually safe, but in some cases it may be associated with side effects such as dizziness, palpitations, swelling of the injection site or **allergic reaction**. Some people experience long-term numbness or tingling and numbness after the treatment. In case of allergy to the anesthetic, the doctor must be informed. **Effect of anesthetic drugs on menstruation:** Dental anesthetics usually do not have a direct effect on the menstrual cycle, but in some women, stress or the body's reactions to the medication may cause changes such as early or late periods. Also, the use of anesthetic drugs in the first days of menstruation may reduce the pain tolerance threshold. It is better to consult a doctor during this time. #### Final word As a result, tooth numbness can have several reasons; including incorrect or insufficient anesthetic injection, the presence of inflammation or infection, anatomical differences in the path of the nerves, severe patient anxiety or nerve resistance, and even the use of some drugs. Accurate knowledge of these factors helps the dentist to create more effective anesthesia by choosing the right technique and drug. In case of experiencing incomplete anesthesia, the issue should be discussed with the dentist so that a more suitable solution can be adopted and the treatment can be performed without pain.