Written by Arthur K. Weathers, DDS Wednesday, 31 March 2004 19:00
This is the second in a series of articles entitled "Access to Success." In Part 1, I discussed the importance of creating an access opening large enough to allow you to work comfortably and reduce the risk of some common problems, such as file breakage. I also discussed some of my favorite tools, such as canal projectors, for improving and refining access to the root canal system. In this article I'd like to take you further along in the process by talking about some of the basics and finer points of improving the quality, speed, and efficiency of your endodontic procedures.
FROM LOW TECH TO HIGH TECH
I'll be discussing 2 high-tech tools—digital radiography and electronic apex locators for making endodontic procedures safer and more efficient, but before I do I want to talk about one of the most humble and often overlooked tools we have available for endodontic therapy. This device is so low-tech that many dentists don't even use it, but I consider it to be one of the more important tools for successful endodontics. Many of us learned to hate it in dental school, and if we haven't discarded it altogether, we often turn what should be a helpful, easy-to-use tool into a complicated hindrance. I'm talking about the lowly rubber dam!
ELIMINATING EXCUSES FOR NOT USING A RUBBER DAM
Using a rubber dam in endodontic procedures has become the standard of care, and at our hands-on Root Camp seminars we encourage dentists to use the rubber dam for every endodontic procedure. Thats every as in 100% of the time. There are no exceptions to this recommendation, and I'll explain why. If you make a mistake or have a problem while performing an endodontic procedure and your patient sues you, the opposing attorney has only to prove that you did not use a rubber dam to demonstrate that you did not follow the accepted standard of care and were negligent in treating his client. This could put you on the wrong end of a substantial judgment.
Equally as important, however, are the positive reasons for placing a rubber dam. The rubber dam actually makes your work safer and easier, and it helps you save time. First, it keeps your patients tongue out of the way. A wandering tongue is one of the peskiest things a dentist has to cope with, and using a rubber dam makes it a nonissue. It also prevents patients from swallowing or aspirating foreign objects, including the very small instruments used in endodontic procedures, and from swallowing water or irrigants. I've often had dentists tell me that their files fit in a handpiece and theres no possibility of patients accidentally swallowing or aspirating a small implement, but in fact the other benefits of using a rubber dam make this objection unsustainable. The bottom line is that using a rubber dam makes your patients experience safer and less stressful, and yours more efficient.
|Figure 1. The No. 12A clamp is designed for the upper left and lower right.|
|Figure 2. The No. 13A clamp is designed for the upper right and lower left.|
|Figure 3. The No. 9M (modified) is designed for anterior teeth, but with the modification described in the article it will work on virtually any tooth.|
Among the other excuses I've heard dentists use for not installing a rubber dam is that they don't know how to choose the right clamp. I can understand this. When you combine all of the dozens upon dozens of different styles of clamps with the small variations in design and quality among clamps manufactured by different companies, you come up with literally hundreds of choices. Let me put your mind at ease about this: you can install a rubber dam on any tooth you'll ever encounter using 1 of only 3 different clamps. Thats right. You only need to have 3 clamps Nos. 12A, 13A, and 9 (modified) (Figures 1 through 3).
|Figure 4. A slight angle view of the unmodified No. 9 clamp showing that the jaws do not line up.||Figure 5. The No. 9 clamp after the lingual jaw has been bent with a pair of pliers until it approximates the buccal jaw.|
I'll take that even further. If you'd like to simplify it even more, you can use a single-type clamp for all teeth. This will enable you to simplify setup procedures even more, and will be much easier for your team. The No. 9 clamp, with a slight modification, will fit any tooth in the mouth. The jaws of the standard No. 9 clamp do not line up, but if you use a small pair of pliers to bend the lingual jaw down until it approximates the buccal jaw, this clamp will grab onto even the most broken down tooth. Figure 4 shows the unequal jaws of the No. 9 clamp prior to bending, while Figure 5 shows the clamp following modification.
|Figure 6. The beaks of this rubber dam forceps are bent slightly outward to allow it to spread the No. 9 clamp enough to fit on large molars.||Figure 7. The No. 9 modified anterior clamp being used on a lower molar.|
The modified No. 9 clamp also works better for anterior endodontic isolation. Approximating the 2 jaws of the clamp allows the modified No. 9 to tilt more to the lingual, pushing the rubber dam out of the way and providing better access. Incidentally, I also occasionally find it necessary to bend the beaks of my rubber dam forceps slightly away from each other (Figure 6) in order to spread the No. 9 clamp enough to fit over a large molar (Figure 7).
If you prefer to use a variety of clamps for different situations, the No. 12A and No. 13A clamps are excellent for use on molars. The 12A is appropriate for lower right and upper left molars, while the 13A is designed for lower left and upper right molars, although it doesn't really matter if you get them reversed. The edges of these clamps are serrated, and they work well in almost all situations, especially for broken teeth and crown preparations where its sometimes difficult to get a clamp to hold.
I also frequently hear the excuse. My patients don't like it when dentists explain why they don't use the rubber dam. This gets us into the area of patient education and managing patient expectations, which can be very important, not just for endodontic procedures but for general practice as well.
First, you don't want to barge into the operatory and announce at the top of your voice that you're going to install a rubber dam and that you're going to use dam clamps and dam clamp holders to do it. You're getting off on the wrong foot unnecessarily if you're not more sensitive to your patients possible apprehension. Tell them reassuringly that you're going to be using a protective shield that will be held in place with a retainer and a retainer holder. The words rubber dam and clamp should never pass your lips in a patients presence. They're not friendly and reassuring terms. If I have to use a rubber dam with a young patient, I often refer to it as a raincoat. Its also important to explain to patients that using the protective shield is a safety procedure that will help prevent them from swallowing the irrigants you use to flush out the infection in their teeth. Your team will appreciate being part of this reassuring practice as well.
Finally, the most common objection I hear to using a rubber dam is that it takes too long to install and makes the whole process less efficient. This is based in part on the fact that in dental school we were taught the most time-consuming and inefficient way of installing a rubber dam that I can imagine. Let me dispose of that objection by reviewing how you can install a rubber dam in about 10 seconds so you'll no longer have any excuse not to use this important tool. This description is based on treating 1 tooth at a time, which is normally the case for endodontic therapy.
|Figure 8. The deep throat punch.||Figure 9. A large hole is punched in the approximate center of the HandiDam.|
|Figure 10. The HandiDam and the No. 9 clamp and forceps.||Figure 11. The Insti-Dam from Zirc is available in a nonlatex material.|
Step 1: Start by using the largest size punch to create a hole in the center of the rubber dam (Figures 8 and 9). Note that the largest hole on the punch is still a lot smaller than the smallest tooth. I recommend either the Aseptico HandiDam (Figure 10), with its built-in plastic frame that does not show up on x-rays, or the smaller Insti-Dam by Zirc (Figure 11), for patients with latex allergies. I recommend not using metal frames because they show up on x-rays, or u-shaped frames, since we've found they can poke patients during use.
Step 2: Slip the hole in the dam over the tooth. Hold down either the buccal or the lingual side of the rubber dam while your assistant holds down the other side.
Step 3: With your free hand, slip the clamp over the tooth to hold the dam in place.
These 3 steps usually take no more than 10 seconds. After the dam is in place, your patients can swallow whenever necessary. This will often mean you do not have to use a saliva ejector. You should, however, advise them not to close their mouth after the rubber dam is in place.
That said, I also want to reiterate a point I made in the first article: do not install the rubber dam until you have at least begun your access opening. This will help make certain you do not isolate and open the wrong tooth. Even if you're not comfortable accessing the pulp chamber before you've put the rubber dam in place, I recommend that you at least outline your proposed access to a depth of about 1 mm before you install the rubber dam. This will have 2 benefits. In addition to allowing you to be certain you haven't isolated the wrong tooth, it will enable you to make sure the patient is fully anesthetized before you install the rubber dam, because the patient will usually let you know if he or she is not adequately anesthetized as you start drilling. And if you accidentally install the dam with the wrong tooth exposed, you'll discover it quickly because you won't see the access you've started.
SPECIAL CASES: BRIDGE ABUTMENT
When you're treating a bridge abutment, you don't need to isolate the entire bridge. Clamp the tooth to be treated and let the rubber move up over the solder joints. If necessary, in cases where there is not enough tooth to hold a clamp, you can clamp the gingiva directly since this rarely causes discomfort. In this case, don't clamp too close to the gingival margin or you may cut off the blood supply and cause gingival sloughing.
You'll notice that I use the term digital radiography and not simply radiography. Thats because I strongly recommend that if you're going to maximize your quality, speed, and efficiency in endodontics, you need to incorporate this powerful new technology into your office. Let me go over a few of the reasons you shouldn't be without it.
Among the first is increased safety. Digital radiography reduces radiation exposure up to 90%, depending on the type of film and film speed its compared to. This is an important selling point for patients. Perhaps even more important, as you progress with treatment you'll be able to take advantage of the additional information gained from mid-treatment x-rays because you don't have to limit the number of images you capture for fear of excessive radiation exposure.
In addition, you'll see each image immediately displayed on a computer screen. This means you save a great deal of time over the course of a root canal procedure when compared to the typical 7-minute wait while film x-rays are processed. Once the images are displayed, the magnification and enhancement that can be done make it an indispensable endodontic tool.
Installing a digital radiography system is going to improve your bottom line, too, along with all the other benefits. If your office takes 25 x-rays a day, your cost for consumable supplies, including film, chemicals, and mounts, amounts to $11.25 a day, using the accepted industry standard of $0.45 per x-ray for consumables. In other words, you're spending between $300 and $500 each month on film, chemicals, and mounting if you take 25 x-rays a day. And it takes an average of 6 to 8 minutes extra for your staff to process each film x-ray, as compared to displaying a digital image of the x-ray instantly. This means that wasted staff time processing 25 film x-rays amounts to more than 3 hours every day. At $35 per hour, this comes to at least $105.
All this adds up to nearly $25,000 a year if you take an average of 25 x-rays a day and your practice is open 200 days a year. Compared to the high-end cost of about $6,000 a year for a lease-purchase plan on a digital radiography system, you're going to improve your bottom line by almost $20,000 every year, and the improved earnings start on day one.
So, assuming you are using digital radiography in your office, among the first things you're going to want to do is take 2 digital x-rays in order to get a good picture of the tooth you're going to be working on prior to proceeding. I recommend that you take 2 radiographs from 2 different angles before you begin root canal therapy. I also recommend that you take x-rays as necessary during the course of treatment to confirm that your procedure is progressing correctly. We think that digital radiography equipment is so important for endodontic procedures that at our C. E. Magic! Endodontic Root Camp seminars we provide every attendee with the opportunity to use a DEXIS digital radiography system, which is the one I selected for my own office, as part of our training.
DETERMINING CANAL LENGTH WITH ELECTRONIC APEX LOCATORS
Although electronic apex locators were developed in the 1960s and have been used in endodontics for some 40 years, recent improvements in the technology mean that this tool now enables you to determine canal length with greater accuracy and reliability than ever before. Electronic apex locators represent the most accurate and reliable way to determine the working length of a root canal. We recommend that all of our Root Camp seminar attendees take advantage of this tool for the best results. If you don't use one, you're making your root canal therapy a lot more complicated than it needs to be.
|Figure 12. The Elements apex locator features a satellite LED readout, which clips onto the patients bib for easy readability.|
Before the introduction of electronic apex locators more than 40 years ago, radiographs were the primary visual method for determining canal length, and their reliability was not very good. Using radiographs to determine canal length was especially difficult in a tooth with multiple roots and multiple canals. While a number of reliable electronic apex locators are on the market, the new Kerr/Sybron Elements (Figure 12) is my favorite.
Note that the pulp chamber should be dry when you are using an electronic apex locator, but the canals themselves should be wet. You should use the largest diameter file that will reach the entire length of the canal when using the electronic apex locator. If the needle jumps around, the file you're using may be too small. Try a larger size until you get a stable reading. Avoid letting the file you're using touch metal restorations in the patients mouth. If this is a problem, then you can enlarge the access opening you've made, or, if this is not practical, use a small piece of a plastic drinking straw to separate the file from the metal restoration.
USING THE ELECTRONIC APEX LOCATOR
For purposes of describing the correct technique for using the electronic apex locator, the Kerr/Sybron Elements device is used, because this is the unit I use in my practice. This device features a satellite display with an LED readout that can be placed on the patients bib for easy viewing without having to turn and look at the main unit.
Step 1. Grasping the satellite cord plug by its knurled section, line up the red dots and gently push it into its receptacle at the front of the unit. The cord may be plugged in or removed only by pulling the knurled section of the plug.
Step 2. Place the patient lead cord into the satellite cord receptacle.
Step 3. Insert either the bifurcated probe or file clip into one side of the patient lead cord receptacle and the lip clip into the other side of patient lead cord. Note that you should insert the file part way into the chamber before attaching the file clip.
Step 4. Once all leads are attached, power the unit by depressing the "on" button.
Step 5. Ensure the unit reads apex in the upper right-hand corner, confirming the unit is in the apex locator mode. If not, press the a/v button to do so.
Step 6. Place the lip clip on the patients lip. Direct contact between the mucosa and the lip clip must be made for proper function.
Step 7. Ensure the unit is functioning properly by touching the probe tip or file to the gingiva. You should notice a change in the display.
Step 8. Touch the bifurcated probe to a file that is in the canal or connect the file clip to a file that is in the canal.
Step 9. Upon contact, the numeric display and a small bar underneath it will appear until contact is broken.
Step 10. Work the file apically until the numeric display reads 0.0, the graphic display exhibits a solid file, and the black apex" bar appears. Note that the graphics should show the file advancing as the display gets nearer to the 0.0 reading.
Step 11. Pull back approximately 0.5 mm to reach the constricture. As you do so, segments of the pie symbol will appear in the lower right side of the screen. When you reach 0.5, the pie will fill in completely and spin.
Step 12. Set the desired working length by adjusting the position of the stop on the file.
Step 13. When contact is broken, the numeric display will show 2 dashes, and the file icon will disappear.
In the next article of this series, I will provide information about 3 more topics—magnification, including the use of loupes and microscopes; new developments in chemical cleaning agents, including EDTA; and the use of sonic and ultrasonic devices—that will further help you improve your access to endodontic success.
Dr. Weathers lectures and publishes on technologies, products, and processes designed to simplify the practice of endodontics. He pioneered a simplified system of nickel titanium files to enhance patient comfort with a 1-visit endodontic procedure. The Level I and Level II Hands-on Endodontic Root Camp seminar series, which Dr. Weathers hosts, offers multiday, hands-on training to improve dental techniques while explaining his theory of "Endonomics," the economics of endodontic case management, from his own multimedia learning center in Griffin, Ga, as well as from the Las Vegas Institute for Advanced Dental Studies (LVI). The editor of the DentalMagic! newsletter and the author of numerous articles on innovations in endodontic treatment products and processes as well as intraosseous anesthesia delivery systems, Dr. Weathers has also introduced the C.E. Magic! "edutainment" interactive learning system to the field of continuing education in dentistry. Dr. Weathers can be reached at (770) 227-3636 or visit CE-Magic.com.
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