4 Frequently asked questions about local anesthesia

Your dentist strives to make your dental experience as pleasant as possible. For more than 100 years, local anesthetics have been a major part of that effort. Learn the answers to these questions to better understand the use of local anesthetics in dental treatments.

  • What is local anesthesia?

A local anesthetic is injected to keep you from feeling pain in a targeted area of your mouth during a dental procedure, such as a filling, tooth extraction, crown, dental emergency or treatment of gum disease. Local anesthesia keeps you comfortable during a dental treatment by stopping nerves from sending pain signals to your brain.

 

Novocaine was once the most widely used local anesthetic by dentists. It was replaced a number of years ago by similar, more modern medicines, such as lidocaine. However, some people still refer to any local dental anesthesia as “getting a shot of novocaine.”

 

  • How long does it last?

Local anesthesia generally works fast and the effects don’t last long. For instance, the numbing effects of lidocaine usually kick in within five minutes or less of the injection and last about one to two hours. Local anesthesia frequently contains epinephrine (also known as adrenaline), which can help its effects last up to an hour longer.

How long the anesthetic lasts depends on the:

  • Dosage given: Higher doses last longer and are needed for more complicated procedures. For example, a root canal may require a higher dose than a filling.
  • Person receiving the dose: Some medical conditions can influence how long the anesthetic lasts.
  • Condition of the tooth: Infection can cause the anesthetic to be less effective, so the dentist may use a higher dose.

The anesthetic can wear off sooner if you increase blood flow in the area with a warm compress or gentle massage. Be careful not to bite down on the numbed area, as you could cause damage. You may find it difficult to eat, drink or speak clearly before the numbness wears off. As the effects of local anesthesia diminish, you’ll usually have feeling in the tooth before you do in your lips, cheeks, or tongue.

 

  • Are there potential side effects?

Local anesthesia is safe for most people but can occasionally cause side effects. Fortunately, the side effects are usually mild and wear off quickly. They include:

  • Tingling and minor pain at the injection site
  • Dizziness
  • Headaches
  • Drowsiness
  • Muscle twitching

Rare allergic reactions can occur, accompanied by difficulty breathing, swelling, hives or the throat closing. If you have a reaction, seek medical treatment immediately. Tell your dentist about any health conditions you have or medications you take to avoid interactions with a local anesthetic.

 

  • Will my dental plan cover local anesthesia?

According to the American Dental Association, local anesthesia is usually considered part of most treatments. As a result, it should carry no additional charge. Ask for a pre-treatment estimate from your dental office if you’d like to make certain local anesthesia is not considered a separate charge.