Dental numbing, sedation and anesthesia guide

The main types of dental anesthesia and sedation

Cleveland Clinic describes sedation dentistry as medication that helps you feel less stressed during dental procedures, used for dental anxiety, lengthy procedures or needs that make it hard to stay relaxed. It is on top of the local anesthetic that numbs the area.

• Local anesthetic: an injection or gel that numbs the area. Numbness commonly lasts one to three hours but can last longer, according to Healthline.
• Nitrous oxide (laughing gas): inhaled through a mask or nosepiece. Cleveland Clinic says calm sets in within three to five minutes, and pure oxygen is given at the end to clear the gas.
• Oral conscious sedation: a prescription pill taken about an hour before the procedure. You may fall asleep, and the dentist will wake you if needed.
• IV sedation: the deepest form of conscious sedation available in a dental office, given directly into the bloodstream. You may fall asleep and not remember the procedure.
• General anesthesia: given by an anesthesiologist in a hospital or ambulatory surgery center.

Is IV sedation the same as general anesthesia?

No. Cleveland Clinic describes IV sedation as conscious sedation delivered in a dental office, where you can respond to questions even if you drift off, while general anesthesia is given by an anesthesiologist in a hospital or surgery center and dentists who use it need advanced specialized training. The NHS also separates them for wisdom tooth recovery, saying not to drive for 24 hours after a sedative injection but 48 hours after a general anesthetic.

Does laughing gas knock you out?

No. Great Ormond Street Hospital says inhalation sedation is not general anesthesia and that the person stays awake, conscious and able to talk. It describes children feeling relaxed, floaty, slightly drowsy, warm or tingly in the hands or feet, taking a few minutes to start and a few minutes to wear off. That page is written for children, and Cleveland Clinic's general description is consistent with it for adults. Whether it makes you loopy varies by person, so ask your dentist what to expect.

Can you eat or drink before anesthesia or sedation?

It depends on the type, and your dental team's instructions are the rule. For laughing gas alone, Great Ormond Street Hospital says no fasting is needed, and suggests a light meal an hour or two before and avoiding greasy or oily food, which can cause nausea. Cleveland Clinic says that for sedation more generally you may need to avoid food and drink for several hours and that your dentist will say how long.

For general anesthetic or sedation, a Chelsea and Westminster NHS leaflet gives an example of strict fasting: no food or drink for 6 hours before, including soup, sweets, milk, tea, coffee and chewing gum, then water up to 2 hours before, and nothing at all after that. The leaflet says fasting is crucial to prevent complications and that the operation may be cancelled on the day if instructions are not followed. Other hospitals and offices may use different times, so use the ones you were given. If you are unsure, call before the appointment.

Driving and getting home

Cleveland Clinic says you can drive afterwards with nitrous oxide, but should not drive for 24 hours after oral or IV sedation and should arrange for someone to take you home. The NHS says not to drive for 48 hours after a general anesthetic or 24 hours after a sedative injection, and Healthline advises arranging a ride home after sedation for wisdom teeth surgery.

Telling your dentist about your health and medicines

Cleveland Clinic says to tell your dentist about all medications, since some can affect sedation and you may need to stop some for a few days. Dentists may recommend delaying sedation procedures during pregnancy, as some sedatives may affect fetal development. Do not stop or change any medicine unless your dentist or doctor tells you to.

Side effects and recovery

Cleveland Clinic lists possible allergic reactions, which providers treat quickly, and common side effects such as bruising at the IV site, dry mouth, lingering drowsiness, headaches and nausea or vomiting, most of which resolve within a day. Contact your dentist if you are still groggy after 24 hours or have persistent nausea or vomiting.

Who might need sedation

Cleveland Clinic says dentists may recommend sedation for dental anxiety or fear of needles, a very sensitive gag reflex or teeth, claustrophobia, difficulty controlling movements, physical, behavioral or cognitive needs, and lengthy procedures such as periodontal surgery. The choice depends on anxiety level, procedure length, health and personal preference.

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