Dental numbing is a routine part of modern dentistry, designed to ensure patient comfort and facilitate various procedures. Its primary goal is to temporarily block pain signals in a specific area of the mouth, allowing dentists to work effectively without causing discomfort. This approach has transformed dental care, making treatments from simple fillings to complex surgeries a pain-free experience.
The Numbing Medications
Dentists primarily use local anesthetics to numb the mouth. These medications temporarily block nerve signals where applied. Lidocaine, also known as Xylocaine, is the most commonly used local anesthetic in dentistry. It is fast-acting and often combined with epinephrine, a vasoconstrictor, to prolong its effects and reduce bleeding.
Articaine is another frequently used local anesthetic, known for its ability to diffuse effectively through tissues, including bone, beneficial for certain procedures. Mepivacaine is a common choice, offering rapid onset and moderate duration for routine procedures. It can be used with or without a vasoconstrictor, which can be advantageous for patients with certain medical conditions.
Bupivacaine, a longer-acting anesthetic, is sometimes selected for more extensive procedures or when prolonged pain relief is desired after treatment, such as surgical extractions. Before injections, dentists often apply topical anesthetics, typically gels or sprays containing benzocaine or lidocaine, to desensitize the gum tissue surface and minimize the initial sensation of the needle.
How Numbing is Applied and Works
The process of numbing usually begins with the application of a topical anesthetic. This gel or spray is placed directly onto the gum tissue where the injection will be given. The topical agent works by temporarily desensitizing the surface, reducing discomfort from needle insertion.
Once the topical anesthetic has taken effect, the dentist administers the local anesthetic via a fine needle. The injection is precisely delivered near the nerves that supply sensation to the specific tooth or area requiring treatment. Local anesthetics function by temporarily blocking nerve signals to the brain. They achieve this by interfering with the movement of sodium ions into nerve cells, which prevents pain messages from reaching the brain. This makes the treated area feel numb while allowing the patient to remain conscious.
Depending on the area and procedure, the injection may be an “infiltration” to numb a small area. Alternatively, a “nerve block” can numb a larger region, like an entire section of the jaw.
What to Expect
As the numbing medication takes effect, you will typically notice a tingling sensation, followed by a feeling of heaviness or complete numbness in the treated area. Your lips, tongue, or cheek might feel swollen or thick, even though they are not visibly larger. It is normal to feel pressure or movement during the dental procedure, but you should not experience pain.
The duration of numbness varies depending on the type of anesthetic used and the specific area treated. Short-acting anesthetics may wear off in 1 to 3 hours, while longer-acting ones can last 2 to 8 hours, particularly for lower jaw procedures which tend to stay numb longer.
Dentists advise avoiding eating or drinking hot beverages until the numbness has completely disappeared to prevent accidental biting or burns. Staying hydrated can help the body process and eliminate the numbing agent. If numbness persists unusually long or is accompanied by pain or swelling, contacting your dentist is advisable.