How does the dentist numb you for a deep cleaning?

When you go to the dentist for a deep cleaning, known as scaling and root planing, your dentist will likely numb the area being worked on. This is done to minimize any discomfort or pain during the procedure. There are a few different ways dentists can numb the teeth and gums for a deep cleaning.

Topical anesthesia

One method is applying a topical anesthetic directly to the gums. This is often done prior to giving an injection. The topical anesthetic numbs the surface of the gums so the prick of the needle is less painful.

Common topical anesthetics used by dentists include:

  • Benzocaine – This is applied as a gel or ointment and takes effect within 1-2 minutes. Benzocaine numbs the area for about 20 minutes.
  • Lidocaine – Lidocaine comes as a gel and takes effect within 1-5 minutes, providing numbness for about 20 minutes.
  • Prilocaine – Like benzocaine and lidocaine, prilocaine is applied topically and offers rapid, short-term pain relief.

The topical anesthetic is applied using a cotton swab on areas of the gums that will be numbed with an injection. Leaving it on for at least one minute allows it to fully penetrate the surface tissues.

Dental injections

Once the topical anesthetic has been applied, the dentist will administer an injection of a local anesthetic. This numbs the teeth and gums more thoroughly so that deep scaling and root planing can be performed comfortably.

Common dental injections used for deep cleanings include:

  • Inferior alveolar nerve block – This targets the lower teeth by injecting anesthetic into the ligament below the roots. It numbs the lower teeth, gums, lip, chin and tongue on the side where it’s administered.
  • Greater palatine nerve block – This is used for upper teeth and is injected in the palate. It numbs the upper teeth, gum and palate.
  • Nasopalatine nerve block – Targeting the front upper teeth, this is injected between the roof of the mouth and upper gums. It numbs the upper front teeth, gum, palate and nose area.
  • Local infiltration – The dentist may also administer individual injections around specific teeth as needed to thoroughly numb the area being worked on.

The injections use a local anesthetic such as lidocaine, articaine, prilocaine or bupivacaine. The numbness from dental injections lasts about 1-3 hours, so they can numb the area for the entire deep cleaning procedure.

What does it feel like when the dentist injects the anesthetic?

When you first feel the needle penetrate the gum tissue, there is slight pinching or pressure. The topical anesthetic helps minimize this. Within 30-60 seconds the anesthetic starts to take effect and the area will begin feeling numb.

As the anesthetic starts working, you may feel tingling or numbness in your lip, tongue or face depending on the area injected. As the injection takes full effect over several minutes, the area being numbed will feel completely numb to touch, pressure and pain.

Your dentist may massage the area to distribute the anesthetic and speed up the numbing process. They may ask if you can feel any pain as they probe the gums to ensure you are adequately numb before starting the deep cleaning.

Let your dentist know if you still feel any discomfort during the procedure and they can give supplemental injections to re-numb the area as needed.

What kinds of anesthetics do dentists use?

The most common local anesthetics used by dentists are:

  • Lidocaine – This is the most widely used dental anesthetic due to its rapid onset and intermediate duration of action. It takes effect in 1-3 minutes and lasts about 1-2 hours.
  • Articaine – This numbs slightly faster than lidocaine. It’s also more potent and may be used for procedures requiring deep anesthesia.
  • Prilocaine – Similar to lidocaine, this anesthetic has a quick onset but has a slightly shorter duration than lidocaine.
  • Mepivacaine – Has an intermediate onset and duration, similar to lidocaine. It’s less likely to break down in inflamed tissues.
  • Bupivacaine – While it has a slower onset, it is very potent and provides prolonged numbness lasting about 4-8 hours.

Dentists select the type of anesthetic based on the specific tooth and what level of anesthesia is needed. The combination of topical anesthetic and injections provides effective numbness for deep cleanings.

How long does numbness last after a deep cleaning?

On average, numbness from dental anesthesia lasts about 1-3 hours after the procedure is done. However, this varies based on the type of anesthetic used:

  • Lidocaine – Numbness lasts about 1-2 hours.
  • Articaine – Numbness lasts about 1-2 hours.
  • Prilocaine – Numbness lasts about 30-60 minutes.
  • Mepivacaine – Numbness lasts about 1.5-3 hours
  • Bupivacaine – Numbness can last about 4-8 hours.

Keep in mind that individual metabolism and the amount of anesthesia play a role too. If you received multiple injections or had a greater volume administered, the numbness may last longer.

The numbness gradually wears off over the duration of action. Sensation returns slowly, starting with tingling and eventually full sensation is restored.

While waiting for the numbness to subside, be careful drinking hot liquids to avoid burning your mouth. Also take care eating and talking so you don’t accidentally bite your lip or tongue.

What to expect during the procedure

Once your dentist has thoroughly numbed the area needed for the deep cleaning, the procedure can begin. Here’s what you can expect:

  • The dentist uses scaling instruments to remove plaque and tartar from above and below the gumline, especially in areas not reachable by normal brushing and flossing.
  • Root planing is done to smooth areas of damaged root surfaces. The dentist may use special curettes, lasers or ultrasonic tools for precise root planing.
  • Your dentist will thoroughly rinse away all dislodged plaque and calculus as they work. They may also use an antimicrobial rinse to help reduce bacteria.
  • The cleaning is meticulous, often taking an hour or longer depending on the amount of tartar accumulation and the number of teeth involved.
  • Your gums may be injected with local anesthesia multiple times throughout the procedure to maintain numbness.
  • Although no drilling is involved, you’ll hear the scraping and suctioning sounds of the dental instruments and equipment.

Let your dentist know right away if you feel any sensitivity or discomfort during the cleaning so more anesthetic can be administered.

Why is numbness necessary during deep cleanings?

There are a few key reasons why proper numbness is so important for deep cleanings:

  • Prevents pain – Removing hardened tartar deposits below the gumline would be quite painful without anesthesia. The numbness allows you to sit through the lengthy procedure comfortably.
  • Allows for meticulous cleaning – Numbness lets the dentist thoroughly scale, debride and plan areas that would otherwise be too sensitive to touch. This leads to better clinical outcomes.
  • Minimizes gag reflex – Having anesthetized gums and soft tissues prevents the gag reflex from being triggered during deep cleanings.
  • Reduces infection risk – Numbness controls pain so there is less movement and discomfort during the procedure. This results in less bleeding and faster healing.

Patient cooperation is extremely important for the dentist to perform the deep cleaning successfully. Anesthesia facilitates this by keeping patients relaxed, still and comfortable throughout the procedure.

Are there any risks with dental anesthesia?

While very safe overall, dental anesthesia does carry some potential risks including:

  • Allergic reaction – Some individuals may have an allergy to common local anesthetics like lidocaine. Reactions are usually mild but can occasionally be severe.
  • Numbness beyond the procedure – In some cases, residual numbness in the lips, tongue, chin or face may persist for several hours longer than normal.
  • Nerve injury – There is a slight risk of nerve trauma from the needle. This may result in prolonged or permanent numbness in rare cases.
  • Hematoma – A blood clot or bruise may develop at the injection site and cause temporary swelling.
  • Methemoglobinemia – Very high doses of prilocaine can cause this rare condition reducing the blood’s oxygen carrying capacity.

Your dentist takes necessary precautions to minimize risks and make the anesthesia process as safe as possible. Make sure to discuss your medical history before any procedure requiring dental anesthesia.

Tips for a more comfortable experience

You can take certain steps before and during your appointment to help maximize your comfort:

  • Arrive early – This gives the topical anesthetic time to take effect before injections.
  • Stay relaxed – Being tense can increase sensitivity to pain, so focus on breathing slowly and deeply.
  • Communicate – Tell your dentist if you feel any discomfort during the procedure.
  • Avoid caffeine – Caffeine can interfere with anesthesia, so avoid coffee and other stimulants beforehand.
  • Be well hydrated – Drink water before and after to help metabolize the anesthesia and avoid dizziness.
  • Take over-the-counter pain relievers – Your dentist may recommend taking ibuprofen or acetaminophen before appointments for added comfort.
  • Listen to music – Wear headphones and listen to calming music to create a distraction.
  • Use a rubber bite block – This protects your teeth from grinding or clenching during the procedure.

Following your dentist’s recommendations for preparing for the deep cleaning will lead to the most comfortable experience possible.


Dentists use topical anesthetics and local injections to fully numb your teeth and gums for deep cleanings. This allows them to thoroughly remove tartar and plaque from above and below the gumline without causing you pain or discomfort. While the injections may cause some mild initial pricking or pressure, the area quickly becomes numb within minutes. With proper anesthesia, patients can relax while the dentist meticulously scales and root planes the treatment area. Though dental anesthesia is generally very safe, your dentist takes precautions to minimize risks like allergic reactions, extended numbness or nerve injury. Communicate with your dentist about your concerns and follow their recommendations for maximizing your comfort during deep cleanings.

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