IV sedation or a general anaesthetic for dental treatment?

In short: with IV sedation you are drowsy and relaxed, breathing for yourself, and able to respond, and you may remember parts of the appointment. With a general anaesthetic you are unconscious, an anaesthetist manages your airway and breathing, and you wake afterwards in recovery. Sedation suits many people having moderate amounts of treatment. A general anaesthetic is more often used for longer or more complex treatment, for young children, or when sedation would not be enough.

What makes dental treatment different

In most procedures the anaesthetist and the surgeon work in different places on the body. In dentistry they share one space: your mouth is both the treatment area and the entrance to your airway. Water, debris and sometimes blood collect at the back of the mouth while you are drowsy or unconscious.

• Under sedation, you are still protecting your own airway. The dental team keeps the area clear with suction, and the level of sedation is kept at a point where you can still swallow and cough. This is one reason sedation for dentistry is usually kept at minimal or moderate levels.
• Under a general anaesthetic, your protective reflexes are switched off, so the anaesthetist secures your airway, usually with a breathing tube, and takes over that protection for the whole treatment. The Australian Society of Anaesthetists lists damage to teeth among the possible complications of airway equipment, so tell the anaesthetist about loose teeth, crowns and bridges.

Side by side

How each one feels

IV sedation. A cannula is placed in your hand or arm and the medicine is given gradually. Within a few minutes many people feel heavy, warm and unconcerned. You may hear the dental team and feel pressure or vibration, but the local anaesthetic numbs pain. Time often seems to pass quickly. Afterwards you may feel alert sooner than you expect, even though your judgement is still affected.

General anaesthetic. The anaesthetic is usually started through a cannula and takes effect within moments. The next thing you notice is waking in a recovery area. It is common to feel sleepy, to have a sore or dry throat for a day or two, and sometimes to feel sick.

When sedation may be enough

Sedation is often considered for adults who are anxious but able to cooperate, for a few fillings or extractions, for implant placement, and for some wisdom tooth removal. It may not be enough if you need a long appointment, if previous sedation did not help, or if you cannot keep still or keep your mouth open.

When a general anaesthetic may be suggested

A general anaesthetic is more often suggested for extensive treatment in one session, for deeply impacted wisdom teeth or other oral surgery, for young children who need a lot of treatment, and for some people with disability or severe anxiety. It is not automatically the stronger or better choice. It involves more preparation, a recovery area and usually a facility fee, and the decision depends on clinical need.

Some health conditions point the other way, towards a hospital setting for either option. These include significant heart or lung disease, severe sleep apnoea and previous difficulty with anaesthesia. Your anaesthetist will advise.

Preparation compared

The basics are the same for both:

• fast exactly as your own anaesthetist instructs. ANZCA’s sedation guideline applies fasting to IV sedation of any level, so do not assume that sedation means you can eat as usual
• check what to do with each of your medicines
• arrange a responsible adult to take you home and stay with you
• plan a quiet day with no driving.

A general anaesthetic sometimes needs a longer pre-anaesthetic assessment, including tests if you have medical conditions. See preparing for dental sedation or anaesthesia.

Recovery compared

Both leave you unfit to drive, operate machinery or make important decisions for at least 24 hours, according to the Australian Society of Anaesthetists. After sedation you may feel close to normal within hours. After a general anaesthetic, tiredness, a sore throat and nausea are more likely, and recovery may take longer. See after your procedure.

Risks compared

• Sedation: drowsiness, nausea and bruising are common. Breathing can slow, oxygen levels can fall, and sedation can become deeper than planned, which is why you are monitored throughout.
• General anaesthetic: nausea, sore throat, headache and tiredness are common. Damage to teeth, allergic reactions and aspiration are less common. Serious complications are rare, and your anaesthetist will explain how they apply to you.

In an emergency, call 000. This information is general and does not replace advice from your treating practitioner.