Every week I encounter people that would rather repaint the Sydney Harbour Bridge with a toothbrush than have dental treatment. "Oh, you're a dentist?", they say. "I hate dentists". Part of me feels like saying, "Gee thanks, I hate you too!", though I reason this would probably be unproductive. It's nothing personal of course, some people are just plain scared of dental treatment. Sometimes it's because of a bad experience, sometimes it's harder to pin down the cause. No matter the reason behind a dental phobia, there are many ways to deal with it. One option is to manage the anxiety chemically with sedation, which in itself has many options to choose from...
"Laughing gas" is the commonly used name for this form of sedation. A mix of nitrous oxide and oxygen is administered through a rubber hood that sits over the nose. The patient inhales the mix through their nose for the duration of the dental appointment. Nitrous oxide can reduce anxiety by producing a "floaty", detached sensation. It is also a mild analgesic, so will reduce any feelings of pain. Nitrous oxide has many advantages. As the patient stays conscious, it is very safe and there is no need for the additional monitoring equipment necessary with deeper forms of sedation. The patient is also able to cooperate with treatment and follow instructions, and will be feeling back to normal after a brief recovery period, (usually less than half an hour). It is an excellent way to build confidence, as the nervous patient will remember the appointment and associate dental treatment with a feeling of being relaxed. Some people don't enjoy the sensation, and find that the detached feeling they get increases their anxiety. I have also come across people who found the nose hood made them feel claustrophobic. Fortunately it's easy for these patients to simply let the dentist know, and within a few minutes of breathing plain oxygen they'll be feeling back to normal. Occasionally nausea is a side-effect, the risk of this increases with higher concentrations of nitrous oxide and with longer sessions. Another disadvantage is that if the dentist is working on the upper front teeth, the hood can sometimes get in the way.
Diazepam, (commonly known by the brand name Valium), or one if its derivative drugs, (temazepan and oxazepam), can be prescribed by a dentist for a nervous patient. They are taken in tablet form about an hour before the appointment, and produce a relaxed sensation. Often people will fall asleep very easily, but can also be roused so are not really "knocked out". Like nitrous oxide, they work well for reducing anxiety while building confidence. If a dental phobia is something the patient wants to work on, the dose can be lowered with each appointment until the patient is comfortable being treated without sedation. There is no additional equipment needed, so no monitors, cylinders of gas, or nose hoods to get in the way. Depending on which drug is used, the effects can last for many hours. This means the patient cannot drive themselves home, and will not be fit for work or anything that requires concentration for the rest of the day. Another down side is that benzodiazapenes are addictive, but an addiction is highly unlikely to occur from only a handful of dental visits. They may not be suitable for some people depending on their overall medical condition.
This is known as the "green whistle" in ambulance circles. It is an anaesthetic gas which is inhaled through a self-contained green tube held by the patient, about the size of a small banana. The patient gains relief from both anxiety and pain for a few minutes after each inhalation. A phenomenon called "retrograde amnesia" often occurs, which means despite the patient being awake the whole time, they remember nothing afterwards. Being inhaled through the mouth, it is not a great fit for dentistry. I have only found it useful in emergency situations, where a very nervous patient requires an extraction immediately and there is no time for planning a different form of sedation.
This is a deeper form of sedation, often marketed as "sleep dentistry". It requires the skill of a separate sedationist, who is usually an anaesthetist, or specially trained medical doctor or dentist. Drugs are given intravenously, (directly into the bloodstream), that make the patient sleepy and take away any feelings of anxiety. Patients will often fall asleep, but can be woken with normal stimuli like loud noise. Retrograde amnesia occurs, so the patient remembers nothing about the procedure. If you've ever had the pleasure of a colonoscopy, it is a similar type of sedation. There is a higher risk of complications with twilight sedation, which is why someone separate to the dentist must be present to administer it and monitor the patient throughout the procedure. Additional monitoring equipment is also required to keep track of the patient's vital signs. As the patient doesn't remember the procedure, twilight sedation is not helpful for someone trying to overcome their dental anxiety long-term.
Unlike the above forms of sedation, this cannot be carried out in your dentist's normal rooms. General anaesthetic can only be given in hospital by an anaesthetist, because it carries additional risks. The patient is completely unconscious and will not be able to be woken until the anaesthetist makes it so. Which drugs are used and how they are given will depend on the patient, the anaesthetist and the procedure. On the downside is a need to fast before the procedure, and a risk of complications from the drugs given. Some people feel nauseous and lose their lunch afterwards, some people will have an allergic reaction, some people will wake up feeling fine. These and many other risks are why a general anaesthetic is usually reserved for big one-offs like having wisdom teeth extracted, or extensive reconstructive dentistry.
If you are terrified of having dental treatment, please, please, please tell your dentist. There are so many options available to help make you comfortable, and not just the drug-induced relaxation described above. Simply finding the right dentist you can trust may be the key, or perhaps hypnotherapy or simple relaxation techniques will work for you. The best thing a nervous dental patient can do is be proactive about their dental care. See your dentist regularly for check-ups and preventive care, so you need never be staring down the barrel of a scary course of treatment ever again.