One of the reasons I have taken a special interest in the dental patient with anxieties and fears is that I am an anxious patient myself. I get sweaty palms whenever I sit in the chair for restorative work. In my case it comes from memories of painful dental care as a child, with a dentist who didn’t use novocaine. Now, when those anxieties come back, I have trouble getting numb. I know there are some dentists who say they don’t believe it when patients tell them they aren’t numb after a novocaine injection. Not me. I believe those patients because I’m one of them! I had an experience when I needed some orthodontic extractions, and in spite of shot after shot, the dentist couldn’t get me numb. The novocain hit the nerve, but it just wasn’t working. It was terrible! I had the same thing happen with a root canal treatment. Once I start feeling that a dental appointment might have trouble, I start worrying that I won’t be numb. When that happens, I simply cannot talk myself out of it and I need a little gas or something. So I know what some of you go through.
As I have watched people deal with the stress of dental care, relating that to my own experience, it is clear that some level of sedation dentistry is needed to make most anxious patients comfortable. It works. When the patient is anxious, there is some body chemistry that is at work to make the novocain not be effective. If there is enough anxiety, I have given injection after injection only to see the tooth never get completely numb. Then, what little numbing I could achieve would completely wear off in a matter of minutes. That same patient, given either nitrous oxide gas or an oral sedative medication, could be made completely numb and comfortable.
Here is the sequence of events, as it happened time after time: The anxious patient is in the chair. I give an injection of novocain. I verify that it is starting to take effect within a few seconds, indicating that the injection is on target. I then give it the approximately ten minutes needed to become completely numb. I start work. Even though their lip is numb, they feel the pain in their tooth. I give a second injection, which is also on target. The lip is very numb but they still feel pain when I work on the tooth. So I stop, explain that we need something stronger, and they agree to have nitrous oxide gas. I administer the nitrous oxide. They become more relaxed. They’re still not completely numb, so I can’t just start work. I learned that I need to wait until the nitrous oxide has taken effect and give the novocain again. Now they’re numb and comfortable.
Rationale for Sedation Dentistry
Pain is a complex issue. There is a biochemistry of pain and a psychology of pain, and you can’t fully explain pain and its intensity without understanding both.
There are pain receptors which transmit impulses to the brain. The brain receives these impulses and then interprets them as pain. Health practitioners attempt to block pain by interfering with this process at one of the steps. We can either try to inhibit the pain receptor, block the transmission, or affect the brain’s interpretation of the stimulus.
In addition to the chemistry of pain perception, past experiences also influence the interpretation of a stimulus as pain. Anticipation, for example, can greatly magnify a response. There are times when, because of prior conditioning, past experience, or level of anxiety, the mere gentle touching of a person can be interpreted as pain. Other psychological factors also have an effect. Additionally, there are varying levels of pain tolerance from one person to another. Some people feel pain, yet it doesn’t bother them, while others can be subject to the same pain and not be able to tolerate it.
Additionally, there are interactions between hormones related to emotions and the transmission of the pain. The dentist can give an injection of local anesthetic, and, if the anxiety level of the patient is high enough, the pain transmission will still occur, in spite of the fact that the local anesthetic is supposed to be blocking the transmission. As I mentioned above, I witnessed that effect many times in my dental practice. If we treat the anxiety with medication and then re-administer the local anesthetic, then it works. There are also times when the local anesthetic may work but, because of anxiety, it wears off very quickly.
Without proper empathy, it is difficult for a dentist to fully treat pain during treatment—there will be a lack of understanding of the emotional and psychological aspects of the pain and its interpretation. The dentist may take the attitude that “you’re just being a difficult patient. I’ve done what I was trained to do to handle your pain, and if that’s not enough for you, it’s your fault.” Therefore, he or she will make no further efforts to handle the situation and either insist that you endure or may refuse to treat you.
The dentist may feel that the patient should be able to control their anxiety. However, it is beyond the patient’s control—he cannot merely reason himself out of it. It is there, and he has to deal with it, and it is the dentist’s job to help.
Dentists who are successful in treating anxious patients have more empathy and will be willing to use sedation dentistry or whatever techniques are needed to help them.
Sedation Dentistry Treatment Options:
For low levels of anxiety, nitrous oxide gas works well. It brings the level of anxiety down just enough for the local anesthetic to work and the treatment to be comfortable.
For higher levels of anxiety, which occurs when there is a history of traumatic dental treatment, orally administered conscious sedation may be indicated. For many years in my office we used diazepam (Valium®) and meperidine (Demerol®), which are excellent medications for lowering the level of anxiety. They give a feeling of euphoria that seems to help erase some of the prior negative conditioning. More recently, oral triazolam (Halcion®) has become very popular with sedation dentists. It is very similar to diazepam, and also has a high level of safety. But it wears off more quickly than diazepam, and thus is more convenient for patients. Many dental practices are offering this option.
Sometimes, with very high levels of dental fear, patients, in spite of very adequate levels of sedation medication, still cannot seem to endure the dental treatment. However, after the appointment, because of the amnesia induced by the medication, they may not be able to remember the appointment. The treatment then is successful in their mind and this successful experience works for their benefit by reducing their anxiety in subsequent appointments.
Often, patients with memories of traumatic dental care, after a few appointments with sedation dentistry, are able to move away from the sedation. With a few successful dental appointments under the patient’s belt, the doctor can lower the level of medication so that they remember the appointments with greater and greater clarity, until they no longer need any medication. I saw this happen repeatedly.
Oral sedation with the proper medications has an excellent safety record. Valium® by itself is extremely safe, even in large doses. Hoffman-LaRoche, the manufacturer of Valium®, has data on file showing patients who have taken up to 2000 milligrams (that would be the equivalent of two full bottles of 10 mg. tablets) in attempts to commit suicide, and no rescue medications or other rescue measures were needed, because vital functions were not adversely affected. Triazolam is of the same drug family, and is also extremely safe. Nevertheless, as a precaution, dentists using triazolam or diazepam should employ monitoring equipment such as a pulse oximeter to make sure that the patient is adequately oxygenated.
Further Information on Sedation Dentistry:
- See our page about conscious sedation for further information for patients undergoing this treatment.
- An excellent web site with a wealth of information about dealing with dental fear is www.dentalfearcentral.org. Check them out.
- See our page on Iowa sedation regulations for an explanation of the issue of sedation and the current rules adopted by the Iowa Board of Dental Examiners.
- The extraction of impacted wisdom teeth is a particularly traumatic appointment, and sedation may be particularly indicated for this procedure.
- Read Dr. Hall’s blog posts about dental fear, where he answers questions from visitors. You may also want to read his posts about sedation dentistry.
Options for treating dental fear:
Here are some of the options dentists have at their disposal for treating anxious patients, depending on the patient’s level of anxiety and body chemistry:
- stereo headphones (a distraction that can help relax you)
- virtual reality glasses (a more potent distraction)
- extra-strength novocain
- anti-anxiety premedication (for mild anxiety)
- nitrous oxide gas (also for mild anxiety)
- oral sedation
- intravenous sedation
(for moderate to severe anxiety)
(for severe anxiety)
For my own treatment, the nitrous oxide gas is enough to take care of me. Give me a little gas, and then the novocain works and I’m good. Without the gas, I have had problems.
This content was written by Dr. David Hall. Click here to ask Dr. Hall a question.