Michael C. Goldman, DDS
Laser Root Canal Treatment
What is it? Is it any good?
Of the e-mailed questions I get - and I get a lot - probably 75% or 80% of them are about Root Canals. Lately several of you have asked about laser root canal treatment.
Lasers have been coming on strong in the dental field and I believe they hold great promise as equipment and applications evolve. Lately, some dentists have been using lasers to help in root canal treatment (RCT).
Here's a drawing I made to illustrate the important parts of a tooth root regarding RCT.
I would like you to notice that the bulk of the root is made up of Dentin. Through the center is a hollow space called the Main Nerve Canal. That's where the nerve and blood vessels normally are
The outer covering of the root is Cementum.
The Dentin is made of a crystalline structure with MILLIONS and millions of tiny "holes" or "tubes" throughout it, from the nerve canal space all the way to the cementum. These "tubes" are called Dentinal Tubules. They are known to be big enough for bacteria to get inside and "hide".
In addition to the main nerve canal, there are typically smaller branches of nerve called accessory nerves. There could be many of these in any tooth root.
When RCT is done, the contents of the Main Nerve Canal is cleaned out and filled up with some inert material (usuallly gutta percha).
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If you haven't done so, you really should read the other two articles on RCT in this website to get a fuller understanding of many of the details and controversies and then come back to this one and it will make more sense.
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There are many ways to clean out the nerve canal. The problem is that if it is not completely cleaned out and sterilized.... and bacteria are left in the root...... then the bacteria may be able to mutate, multiply and become a source of chronic toxicity long after treatment is over.
We know that bacteria can go from the main nerve canal out into the dentin through the millions of tiny tubules. We also know that at best we can only clean out the main nerve canal and perhaps a large accessory canal here and there if we are lucky enough to find it. Most of the time we don't even know how many accessory canals there are or where they are. These accessory canals contain nerve and blood vessel tissue, too, and this tissue is food for bacteria.
For a long time now I have proposed that all RCT be done using calcium hydroxide for a month to not only kill bacterial both in the main canal but throughout the root with all the tubules, but also because it will dissolve remaining tissue that the dentist was not able to remove.
Generally the "holistic" dental community has not favored doing RCT and mostly recommended extraction. I have dealt more with these issues in the other RCT articles in this website. Recently, lasers have been adapted to RCT use and are being promoted by some in the "holistic" community.
Lasers may be the greatest thing since sliced bread, .... or ... they may not...we really don't know very much yet. But just because they are "hi-tech" and very expensive, that does NOT mean they are good!!!! They are simply another tool to use.
Keep in mind that the inside of a tooth root system is branched, much like anything in nature. Like the branches on a tree or the branching of arteries and veins in the body...that's the way nature makes things. Things in nature are also not flat or straight. They are generally curved in a sort of harmony of chaos. Imagine looking down at a river and its large and small offshutes from an airplane. That's nature.
Lasers shoot out a beam of light in a straight line. Not like a light bulb, where the light goes out all around. What makes a laser a laser is that the light is different. It is in phase with itself and all the waves are parallel with each other. The light is a parallel beam of intense light. It goes straight out the tip of the laser instrument in one direction only. You've probably seen or used laser "pointers" that shoot a small straight beam of red light . Often lecturers use them to point to areas of a projected slide on a wall or screen from a computer projector or slide projector.
The bulk of the tissue in the main nerve canal can be pretty easily removed with many time-tested techniques. There is no doubt in my mind that a laser can also do a good job of removing that tissue. That's not the problem. It's the little offshutes and hidden places inside the tubules. The laser can't penetrate them as far as I know. Or not very far beyond the main nerve canal inner surface. The bulk of the dentinal tubules and accessory canals would still be potentially contaminated. Claims are being made that this is not so, but independent research needs to be done and published to convince me. I am not just being a stubborn disbeliever. There are reasons I feel this way.
First is the idea that as I said the laser light goes in a straight direction that would not easily follow the tortuous curves and bends of the nerve canal. Second, the laser probe is too large to get into the smaller accessory canals even if we knew where they were (and we don't).
Third, the laser can melt and fuse much of the inner surface of the nerve canal which means to me that medications placed in the canal are blocked from getting out into the tubules to kill "hiding" bacteria and to dissolve remaining tissue (which there is certain to be). The bacteria which are the major "holistic" concern, are effectively trapped out in the tubules. Their toxins, if the bacteria survive, can still potentially travel out the tubules to the cementum and out the tooth (into your body).
(Comment: Jan.2004) Additionally, the heat from the laser can do damage to the root, or to the surrounding ligament and bone if it is not very carefully controlled. As just one example, IF the laser is used to clean and sterilize the very tip of the root (arguably the MOST IMPORTANT place) the laser can potentially shoot out through the opening in the root end and the laser then can damage bone ... or worse, if the tip of the root is next to a sinus or major nerve (both of which are common), the laser can potentially damage these structures !!
I am not just "making this up" ... Hebrew University just recently invented a special laser tip (about December 2004) that is designed to prevent the laser from shooting out the end of the root and also to shoot the light sideways for better cleaning effect. I doubt that many of the dentists using lasers for root canals are using one of these special tips. So obviously I am not the only one concerned about these issues.
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An email I recently received from England suggested the following VERY interesting and significant...and scary ideas:
Teeth that once had mercury fillings probably have absorbed mercury within them. Heating them with lasers would likely vaporize that mercury directly exposing the patient and dentist to the most deadly toxic vapor (the most toxic form of mercury is the heated vaporized form - it is quite literally DEADLY ...)
Testing for sterility of the [main] root canal space after laser use may be false because if the tubules are sealed off from the main canal by the laser effect of melting and fusing the dentin, then the bacteria in the tubules may be sealed in the part of the tubule now sealed off from the main canal. But the bacteria could still be alive and well and producing toxins which can continually come out through the outside surface of the tooth root. But testing for bacteria in the main canal space might still show NO BACTERIA.
Those are the kind of questions that still need to be answered by OBJECTIVE RESEARCH DONE BY researchers NOT CONNECTED WITH PROMOTING the SALE and use of a particular laser product !!!!
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***************************************I looked up laser root canal treatment on the internet and found that the root canal specialists have already written an early position statement on it:
• American Association of Endodontists - Lasers In Dentistry Search POSITION STATEMENT ON THE USE OF LASERS IN DENTISTRY Laser use in dentistry was suggested approximately 35 years ago as a means of using energy generated by light to remove or modify soft and hard tissues in the oral cavity. ALaser@ is an
http://www.aae.org/lasers.htmlOn that website, the American Association of Endodontists say:
Laser energy, when added to root canal procedures, presents advantages and disadvantages. Currently, root canal procedures clean the canal space. Studies using extracted teeth inoculated with bacteria have shown that lasers can reduce the quantity of microorganisms. The walls of the prepared canal space contain tubular openings that harbor organisms, and the preparation itself causes formation of a layer of debris (smear layer) composed of organisms and tooth substances. Laser energy can remove the smear layer as well as dentin from the canal wall and will melt and resolidify the dentin to close the tubular openings.
The advantages of using the laser, however, are balanced by several disadvantages. Root canal spaces are rarely straight and more often are curved in at least two dimensions. Root canal instruments used to clean the space throughout its length can be curved to follow the curvatures in a tooth root. Laser probes can clean an area in a root canal space that is straight as long as the probe is in contact with the dentinal wall. The probes are made of glass and cannot be curved to follow the natural curvatures of the tooth root. When in contact with the dentinal wall, laser probes are capable of cleaning an area in the root canal space that is straight.
Further, the interactions involved between laser energy and the tissue cause rises in temperature. These increased temperature
scan char the canal space, damaging it to the point that the tooth may be lost. The increased temperatures also may extend to the outer surfaces of the tooth, damaging the soft tissue that connects the tooth to the surrounding bone.If the temperature is high enough, the bone surrounding the tooth may also be damaged, adversely affecting the entire area, which can result in ankylosis.*************************************************************
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In summary, laser RCT may be the wave of the future...or it may be insignificant. The equipment and the techniques have only now started to be developed...and tested. There are sound reasons to be hopeful for the future and also sound reasons to be skeptical in the present.
One final thought: Root canal specialists (endodontists) do root canals and only root canals...all day long, and mostly by referral from general dentists. There is a lot of money to be made in doing all these root canals and so the specialists are very competitive with each other. This is not to disparage these fine men and women, it is only to make the point that if using laser equipment would give them better, or quicker, or easier, or more patient-satisfying results, they would be the FIRST to jump at this new technology. Laser use in root canals is NO SECRET !
This laser technology is widely known about and advertised. The cost for the equipment, while high, is insignificant if it would result in being more productive on a daily basis and if the results were more satisfying to both the patients and to the referring general dentists ! To my knowledge the endodontists are not yet embracing this new technology. I am very sure that they are, however, watching it VERY carefully and closely...and will want to be the first on their block to have it if and when it looks like the way to go !!!!
I, too, do lots of root canal treatment, and I, too, will be watching closely. When I learn more, you can look here to find out what I think. Have a good one!
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I wrote the various parts of the above article for this website at different times over the past few years prior to 2006. In May 2006, I found a brief abstract in The Compendium, a respected dental journal, summarizing current research conclusions to date. In spite of some advances in lasers and adaptations specifically to root canal treatment, it completely agrees with the ideas I have stated above:
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'Hope this was helpful !
This pamphlet was written in the hope that it will increase understanding about a topic that seems important from time to time. Obviously it is only a part of the whole story, so if you have questions after reading this please do not hesitate to ask or call. Also, if there is a topic that you think would be helpful, please suggest it.
Michael C. Goldman, DDS
General and Cosmetic Dentistry
3815 East-West Highway
Chevy Chase, Maryland 20815
Phone (301) 656-6171
More info about the following is available if you select "topics".
Holistic dentistry is an approach to dental treatment, primarily caring for patients' health and safety from both a conventional as well as "alternative healthcare" point of view. It is sometimes called "biological" dentistry or "biocompatible" dentistry. In it's fullest sense, I believe it acknowledges and deals with the mind, body and spirit of the patient, not just his or her "teeth". See Topics / Info.....
Cosmetic dentistry is about doing quality , esthetic dentistry in a way that looks natural to begin with, and furthermore, can even improve one's attractiveness through techniques such as bonding, bleaching, veneers, caps, implants and more. It can be like "instant orthodontics" in correcting crooked, twisted or misplaced teeth in many instances. Dark or mis-shapen teeth can be restored. Smiles that lack youthful vigor or beauty can be revitalized! See Topics / Info..
In holistic dentistry there is an effort to find biocompatible materials to use to reduce toxicity for everyone, especially the chemically sensitive. Amalgam use is avoided in holistic dentistry (" amalgam free" or "mercury free") due to concern about possible toxicity problems. Amalgam removal and replacement with natural-looking bonded materials is a common holistic dentistry treatment as well as a common cosmetic dentistry treatment. Detoxification, especially of residual mercury deposits in body tissues from amalgams is often done. Root canals are controversial in holistic dentsitry and are discussed under topics. And much more....
Bleaching, veneers, bonding, caps, bridges, and implants are cosmetic dentistry treatments that are also discussed in Cosmetic Dentistry, and more...