by David A. Hall, DDS
Does local anesthetic block pain? In the textbooks, yes. We read how local anesthetic prevents depolarization of the nerve membrane. With the local anesthetic acting on the nerve, it's impossible for the nerve to transmit pain impulses. Theoretically. It doesn't take too long in private practice to realize that there must be other factors at work, because we've all faced patients that are difficult or impossible to get completely numb. I know. I'm one of these patients.
My story of dental-chair trauma begins, as most of these stories do, in my childhood. I had a dentist who didn't use local anesthetic. I tell people I think my fingernail-prints are still in his chair. Pain city! When we moved and got another dentist who used novocaine, I thought it was wonderful. Who invented this stuff? It was great!
I went on with basically comfortable dental experiences, but with some lingering bad memories. Then, when I was in college, I had an uncomfortable incident that brought back some of those memories. I was long overdue for dental care and I decided I needed to get caught up. I refused the dentist's offer of nitrous oxide, so he gave me a shot of novocaine. The problem was the novocaine didn't completely numb the area where the dentist was working. Being kind of a stoic, I didn't let the dentist know I wasn't numb. I just "toughed it out."
In my thirties, I decided to finally get the braces that my family couldn't afford when I was a youngster. I went to a dentist friend to have four premolars extracted. For some reason, I was feeling particularly anxious about this. I knew my bone was dense and the teeth had long, spindly roots. I was afraid the teeth might break off when he attempted to extract them ... and they did!
My palms were sweaty, and it wasn't long before the lidocaine wore off. The dentist gave me more. In about five minutes, it wore off again. He gave me still more. This went on and on — and I never was completely numb! It was a harrowing experience, yet I didn't want to say anything to my friend because he was being so good about it and only trying to help me. But I was exhausted from the pain and stress, and I've had trouble getting numb ever since. Local anesthetic alone won't do it!
About 10 years later, I developed a crack in a tooth and it required endo. The endodontist didn't even have nitrous oxide available in her office. I decided I was going to psych myself up and get numb — I knew it was all in my head! But try as I might to relax, I just couldn't. The endodontist couldn't get me numb. "Give me an intrapulpal injection!" I pleaded. She complied. Whoa — was that an out-of-body experience! My tooth was finally 90 percent numb, and we got through it; but, it took a heavy emotional toll on me.
So ask me if local anesthetic works! For me, it only works if combined with some type of anti-anxiety medication. Nitrous oxide does fine — with the nitrous running, I can get numb! Or, if I take some Valium and Demerol, I'll get numb. But I won't get numb with just a local anesthetic.
I'm unusual in that even though I had serious dental anxieties, I pursued a career in dentistry. There are many patients like me who have serious anxiety problems when it comes to dentistry. We don't know how many for sure. Studies and experience indicate that at least 20 percent of patients have trouble getting numb with just local anesthetic. It's probably more than that because this figure is based on people who show up in the dental office. So, if we, as dentists, intend to serve all types of patients, we need to know how to identify and treat the portion of the population that has so much trouble in our dental chairs.
Your first challenge is to identify the anxious patient. This is not a simple proposition. Often, they will not tell you. Some — especially men — don't want to admit it. Others may just be stoic, noncomplaining types like me who want to try to tough it out, and may not even fully understand their anxiety. You can cut through both of these obstacles to quality treatment for these individuals by simply asking how "novocaine" works for them.
I sit every new patient down in my private office — in a nonthreatening, nonclinical situation — before I do my comprehensive oral evaluation. "I want to get to know you," I will tell them. After asking why they're in my office (i.e., their "chief complaint"), I immediately delve into anxiety-related questions. "So," I'll begin, "what have your previous dental experiences been like? Any traumatic experiences? I like to know these things." Some of them will spill it out right there: "Oh, I had this terrible dentist when I was a kid!" they may say. "He ate children for lunch! I'm sure of it!" Other patients might give me a perfunctory "no" for an answer. Even if they reveal no previous traumatic dental experiences, I still need to know more.
My second question is the key: "When you've had dental work done, I suppose you've had novocaine?" I wait for an acknowledgement and then go on. I use the word "novocaine" because that communicates my meaning to the vast majority of people. "So, does novocaine work for you? Are you numb and comfortable after the injection?" If the patient indicates directly and without hesitation that novocaine has worked fine, then I'm satisfied and I move on to other questions and a review of that person's medical history. If there is any hedging, hesitation, or qualification in the response, I pursue it. Often, patients will tell me that novocaine works fine for them, but then there is a hesitation. If I pause to let the patient talk, then he or she may reveal the problem. "Sometimes, it takes a little extra novocaine," the patient may confess.
Any patient who qualifies the answer to the question, "Does novocaine work fine for you — are you numb and comfortable every time?" is an anxious patient and you need to address that anxiety to properly treat this person.
However, some anxious patients may slip through this detection system. A history of irregular care may tip you off, such as patients who come in only for pain or lost fillings. Or, you may not discover their problem until you actually begin treating them. For example, the local anesthetic is wearing off much more quickly than it should. If you're alert and understand the pain-anxiety-more pain-more anxiety vicious cycle, you'll be able to identify it and treat the patient successfully.
Treating the anxious patient
Treatment of anxious patients needs to be custom-tailored to the level of anxiety of each particular patient. Different patients require different levels of care in order to get them comfortable.
Basic level of care
Let's call the first category of patients the ones who only require a basic level of comfort. This is the level of care for the majority of your patients — those who report no history of dental trauma or problems with local anesthetic. With these people, you need to address basic comfort issues to keep from turning them into anxious patients. Here are the principles used to treat patients in this category:
1. Trust — Trust helps prevent anxiety. If patients trust you, it will help keep them comfortable. There are two elements to trust: 1) skill and 2) caring. If patients feel that you care and that you have the necessary skill to properly treat them, they will put their trust in you and trust dispels anxiety.
2. Sensitivity — You must show sensitivity to the patient's needs. This concept overlaps the concept of caring, but I address it separately because certain behaviors need to be addressed. By sensitivity, I mean that you begin your doctor-patient relationship by meeting the patient in a nonthreatening environment, such as your private office. I also mean that you don't dictate treatment to your patients, but give them options and let them choose their own care. I also mean that you respond to the patient in the operatory. You listen. You also provide the level of information that the patient wants. Some patients want to know everything about what you're doing, while others want you to just tell them when it's over.
You pause in your treatment when your patients need to pause. You put up with their idiosyncrasies. You recognize that many people feel very threatened when you enter their oral cavity. You understand that a sense of powerlessness intensifies anxiety. All of these attitudes and behaviors on your part exhibit sensitivity and help dispel anxiety. This is the level of care you need to give everyone.
But if a person has had trouble with dental treatment before, my experience is that you need to go beyond these basic comfort issues. Let me remind you that I speak from the dual perspective of a clinician and an anxious dental patient. I believe that you need to treat the patient's anxiety pharmacologically to ensure that he or she will have a comfortable experience.
Yes, you can try to manage these patients with psychology. You may even be able to say that the psychology probably will work. But you need to understand the interplay of pain and anxiety. Pain causes anxiety. Anxiety intensifies pain and complicates its management. Also, anxiety is an antagonist to local anesthetic. The presence of anxiety can cause a local anesthetic to either wear off quickly or to not completely block the pain. Finally, when it comes to pain and anxiety, negative experiences are far more powerful and long-lasting than positive ones. If you've had five good dental experiences and one bad one, and you go to sit down in the chair, which one is going to come to your mind? The bad one — we all know that. So, if you create an experience with less than total pain control, you will be feeding into this negative pain-anxiety cycle.
Now, if you have that aura about you that you can use psychological techniques alone and all your patients are comfortable, then I'd say to just keep doing what you're doing. This article, I guess, isn't for you. But if you lack that aura, then my suggestion is to err on the side of controlling the anxiety more aggressively rather than less.
The mildly anxious
Let's call the second category of patients the mildly anxious. These are the people that have had occasional trouble with dental care — an incident where they wouldn't get numb, a dentist who slapped them when they were a child, something like that. I have found that nitrous oxide works well for these people — and they're the majority of the anxious patients. Sometimes you need to even politely insist that the patient use nitrous oxide. They don't understand that they need it in order to be numb. I explain to them that the nitrous oxide strengthens the novocaine, and since novocaine alone doesn't work for them, we need to up the strength with nitrous oxide. It won't impair their ability to drive or work after the appointment, and I make the cost of the nitrous low enough so that money isn't an obstacle and so that they don't think I'm pressing the nitrous in order to increase my revenue. And by polite insistence, of course I don't mean that you force them. You can't do that. But you earnestly urge them, for their own sake, to let you give them what you believe they need in order to be comfortable.
What do you do for the patient who fools you? You don't identify their anxiety until you're in the middle of the appointment? With these people, you need to stop, explain what is happening and how you believe nitrous oxide will help them. Then you induce the nitrous oxide and give more local anesthetic. Whatever it is about the effect of the anxiety on the potency of the local anesthetic, I have found that you need to treat the anxiety and then re-administer the local for the local to have full effect.
Severely traumatized patients
The third category is made up of patients who have had very traumatic experiences in the dental chair or repeated failures to get numb. These people may not get numb even with the use of nitrous oxide, and you will need to go to orally administered sedatives such as Valium or Halcion. Both are great drugs. Valium has a much longer half-life, which, in my mind, makes it a great drug for surgery. The person will still feel the effects of Valium the next day, which will help them rest. But there is a lot of confusion and contradiction in the published information about Valium. Many textbooks suggest an oral dose of 5-to-10 mg. for anxiety. While that dose is completely inadequate for many patients presenting with high levels of anxiety, there is an implication that much more than that would be an overdose. On the other hand, there is actually no safe dose limit established for Valium. Some people have swallowed whole bottles of Valium pills in attempts to commit suicide and failed. In some instances, even though they took a number of pills, they didn't even require resuscitative measures. So, what is the upper limit for a safe dose? I can't tell you. It would be a good idea for our experts to clarify this issue with hard scientific data, not just professional bias.
But Valium is an older drug which, these days, has frequently been replaced with Halcion for oral sedation for dentistry. With a shorter half-life, Halcion is more convenient. It has harder safety data than Valium because there have been some adverse incidents reported with its use.
Patients who become physically sick
There is a fourth category of patient that is beyond the reach of moderate doses of anti-anxiety drugs. These are the people who may become physically sick even thinking about dental care. These patients will need to receive conscious sedation. In times past, conscious sedation was administered with intravenous drugs. More recently, it has become common for dentists to achieve conscious sedation with orally administered drugs. The American Dental Association has recognized and sanctioned this practice, and has published guidelines of educational standards, monitoring, and emergency preparedness for dentists who wish to use these techniques.
Regardless of whether or not it is required by your state board regulations, I feel that you need that higher level of education in physiology and pharmacology and anesthesiology to safely administer oral conscious sedation. There are organizations that will teach you these things. If you're interested, seek out a reputable course and get the training you need to effectively provide this service. You'll become a credit to your profession and a servant of a segment of the population that really needs these services.
My opinion is that there is a large number of people who are not coming in for dental care who would come if we were more proficient at treating their anxiety — up to and including the use of conscious sedation by appropriately qualified and conscientious practitioners. Minimally, however, we should all be willing to be trained in the use of nitrous oxide, as well as in providing modest doses of anti-anxiety medication where indicated. Our patients need it!
Patient Anxiety Categories
1. Those who require a basic level of comfort. These patients have no history of dental trauma.
2. Those who are mildly anxious. These are the people that have had occasional trouble with dental care.
3. Those who have had very traumatic experiences in the dental chair. These people may not get numb even with the use of nitrous oxide, and you will need to go to orally-administered sedatives.
4. Those who become physically sick even thinking about dental care. These patients will need to receive conscious sedation.
