Anaesthesia & Sedation

What is dental anaesthesia?

Dental anaesthesia helps manage pain during dental procedures and surgeries. It blocks painful sensations in specific areas of your mouth. It can be used while you are conscious or unconscious, depending on the procedure, your individual needs, and your doctor’s recommendation.

Local anaesthesia is a medication that makes parts of your mouth numb throughout the procedure. The effects typically last for a few hours after the treatment.

Anaesthesia is a safe way to help patients relax, feel safe, and experience less pain before, during, and after procedures are complete.


There are three types of dental anaesthesia:

  • Local
  • Sedation
  • General


Each type is used for specific pain control purposes.

Dentists determine which anaesthesia is best for each patient based on:

  • The type of procedure (invasive or minor)
  • Patient’s personal preference and needs
  • Patient’s medical history

Local anaesthesia

Local anaesthesia, commonly referred to as “freezing” is the most common type of anaesthesia. Doctors administer it during minor dental procedures, such as:


Commonly-used dental anaesthetics include lidocainearticaineprilocainemepivacaine, and bupivacaine.

Typically, a topical anaesthetic is applied to the injection site, on a specific location in your mouth, related to the area being treated.  After a few moments, the area is desensitized and ready for the anaesthetic to be injected.  The drug usually begins to work within 10 minutes. At this point, the entire area will become numb, but you will still be conscious and able to communicate. The effects of local anaesthesia will last throughout the procedure, and for several hours afterward.


Sedatives and anaesthesia are used for different reasons. Sedation dentistry can help relieve nervousness and anxiety during dental work, reduce pain, or help keep patients from moving. Anaesthesia is used to eliminate pain and discomfort.


Sedation can be administered in mild, moderate, or deep strengths. Mild sedation keeps you conscious, and you can respond to commands. Moderate sedation may put you in a state of semi-consciousness. Deep sedation often makes you unaware of your surroundings and you are unable to respond to stimulation.  Patients with severe anxiety sometimes need a sedative before receiving an injection of anaesthesia, especially if they have a fear of needles. Those with dental phobia, which is an intense fear of visiting the dentist, often visit sedation dentists to receive their care.


At Cliffcrest Dental, we can administer mild sedation only.  A popular option is nitrous oxide (laughing gas), which is an inhalable gas that can be administered via a nasal hood during the procedure.

General anaesthesia

General anaesthesia results in a temporary loss of consciousness. It is used for longer procedures, or if a patient has high levels of anxiety that may cause them to move around.  This type of anaesthesia is administered in hospital settings and clinics specializing in dentistry under deep sedation.


IV conscious sedation

A ‘lighter’ form of general anaesthesia, with IV conscious sedation, the patient is able to respond and breathe on his or her own.  It can be administered by professionals who specialize in the field, so oral surgeons often utilize this technique in their private clinics.  ‘Deeper’ general anaesthesia is typically administered to patients in a hospital setting when they are undergoing invasive oral surgeries including:


  • Bone grafts
  • Corrective jaw surgery
  • General tooth extractions
  • Oral cancer surgery
  • Sleep apnea surgery
  • Cosmetic dental procedures
  • Cleft lip/palate surgery


Benefits of anaesthesia

  • The patient will experience little to no pain during the procedure.
  • Most types of dental anaesthesia are considered safe and effective when safely used.
  • Using anaesthesia can consolidate multiple appointments into one appointment.
  • Anaesthesia can be used in combination with sedation dentistry to relieve anxiety, pain, fear, and discomfort during procedures.
  • Anaesthesia is not a “sleep medication,” which means the patient will remain conscious during the procedure (except general anaesthesia).


Side effects

Dental anaesthesia is a common and safe treatment. Before administration, the dentist should be aware of your full medical history, alcohol abuse history, and any allergies to ensure complications are avoided.

Side effects are rare, and usually only felt with sedation or general anaesthesia. These may include:

  • Nausea
  • Dizziness
  • Vomiting
  • Swelling (in the mouth or at the injection site)
  • Sweating or shivering
  • Confusion
  • Hallucinations
  • Tiredness
  • Lockjaw



Anaesthesiology is considered a safe, effective, and necessary component of dental care. However, there are certain groups that are at higher risk for adverse effects.


Those that should speak to a dental office or anaesthesiologist before their procedure include:

  • Pregnant women
  • Pediatric patients
  • People with special needs
  • Elderly adults
  • Anyone with liver, kidney, lung, or heart problems
  • People with neurological conditions
  • People taking other medications, such as opioids
  • History of allergy to anaesthesia medication


Though complications are rare, there are some risks involved in dental anaesthesia.

Potential adverse reactions include:

  • Allergic reactions
  • Nerve damage
  • Low blood pressure
  • A dangerous increase in body temperature (malignant hyperthermia)
  • Heart attack
  • Heart failure
  • Stroke
  • Failed breathing
  • Death



Key takeaways

  • Dental anaesthesia is a safe and effective way to eliminate pain and reduce anxiety during common dental procedures.
  • Anyone who is feeling anxious about their dental visit should speak with their dentist beforehand.
  • Share your medical history with your dentist and be sure to include any other medications you are currently taking (whether over-the-counter or prescription).
  • Your dentist will explain your different options for anaesthesia or sedation and recommend the best choice for you. They will also provide instructions for before and after the procedure.



Cliffcrest Dental

2995 Kingston Rd, Scarborough,
ON M1M 1P1, Canada