Tell the Patient!
File fractures do happen. One of the biggest mistakes I see is when patients are not told of file fractures. This is not only unacceptable from a referral standpoint; it fails to satisfy the legal concept of informed consent. If you break a mm or two of a #.06 or #.08 file in the canal, is it important to tell the patient? Probably not. - Unless it severely compromises the case. (Ie/, prevents access into the majority of the canal system, makes you treat very short, etc.) On the other hand, leaving half of a Ni-Ti rotary file at the apex of a symptomatic necrotic tooth with a lesion (especially when the canal system has not been cleaned completely) will probably necessitate further treatment. That may mean instrument removal, bypass or surgery. It is VERY important that this be told to the patient AT THE TIME THAT IT OCCURS. That means that if you cannot solve the problem (bypass or remove it) you sit the patient up, remove the rubber dam and explain what has happened. (In the case of the radiographically visible bypassed instrument, it is still important to inform the patient, if only to prevent this from being 'discovered" by another clinician in a subsequent examination.) Only then will you satisfy the legal requirement that the patient is fully informed and able to make a judgment as to how (and if) they wish to proceed with treatment. Be honest with them. Treat them how you would wish to be treated. Most patients are very understanding IF you take the time to explain the complexities and difficulties involved with Endo treatment to them.
Should you break a file in a case and are considering referral to your endodontist for treatment:
1. Take a good radiograph of the tooth after the file has broken. Show it to the patient. This not only allows the patient and referral to see where the file is, it provides legal protection for you. You now have a record that the file was at "this" position when you noted it broke and that the patient was fully informed. Don't hide the fact that the file has broken. If you chose to refer the case at that point, make sure to inform the subsequent clinician. No one likes to get "surprises" or "presents" inside canals that have been referred.
2. Keep the rest of the file in the chart. It offers proof of the fracture and could be beneficial in the unlikely situation that the case goes "legal". (Rare but a distinct possibility in the US.)
3. Try to explain the complexities of the canal system to the patient. Emphasize that we are dealing with very small structures and that although our instruments are flexible, sometimes the canals are so tortuous that the instruments cannot negotiate them adequately. When they see the size of the files, most patients will understand the fragility of the instrument.
4. If you choose to refer - Phone your Endodontist and tell them what happened. Don't be embarrassed. (We break files too!) We are here to help you, not to berate you for the break. (On the other hand, if this kind of referral is the ONLY thing that you send to your endodontist, or if these cases occur routinely, you should expect some " gentle recommendations" on how to avoid this problem in the future.)
5. Fees - This is a very controversial subject. Some dentists feel obligated to pay for the case when they break a file and refer it out. This places the endodontist in a very awkward position. These cases frequently require tremendous amounts of time to treat. Instrument bypass or removal can sometimes necessitate several hours of concerted effort, just to gain canal patency. It is unfair to expect a "professional courtesy discount" when these cases are referred. Expect to pay a full fee. Remember, the endodontist is bailing you out on this one; it isn't a "normal" case. If the patient's insurer has already paid you, it is unlikely that the insurance company will pay for the procedure twice. Please discuss this with the patient or their insurer prior to referral. It is not the job of the endodontist to explain the reason for denial of the patient's claim.
File Bypass - Technique:
The key to bypassing a file is establishing patency with small instruments. You must balance the small size of the file with the stiffness necessary to get past the broken file. That means that initial attempts are made with a #.06 or .08 file. In order to get past the broken fragment it is necessary to put a SMALL sharp rounded bend at the very end of the instrument. This is the KEY and it is one of the most important skills you learn in endodontics. (This bend is also used to get by ledges and other obstructions. The bigger the ledge or the tougher the obstruction, the sharper and smaller the bend should be. I mean REALLY small!) You will go through and discard MANY files. This is normal. After a while you will find a "catch". This is the file negotiating past the instrument. It is very important NOT to remove the file at this point. Use VERY small in and out movements (with lots of irrigation). Very often the file will kink and/or you will not be able to place it in the canal to the same depth. Use a new file, with a new similar bend and repeat the procedure until you feel the file slide deeper. If necessary use small watch-wind ¼ turn and push/ pull motions to move the instrument toward working length. Resist the urge to move up to a #15 file. This file is stiffer and it will feel like you are making progress when in fact the chances are that you are perforating the root. Once you have established patency with a small #10 file, stick with it. If it kinks or bends, don't get frustrated - toss it, bend another file and repeat. If you lose patency, you may have loosened and jammed the broken fragment, go back to the smallest file and repeat the series.
Once you have patency with a#15 instrument, go to K reamers. Use a "place - pull/rotate/withdrawal" movement rather than a filing motion. You will notice two things: (1) The reamer will be deflected by the fragment and you will need to find a consistent path of instrument insertion that is probably different than the initial path (2) Every time you rotate the reamer, you will hear a "clicking" sound as the flutes brush up against the file fragment. This is normal. As the canal size increases so does the risk of pushing the fragment deeper (especially larger fragments). You must avoid placing an instrument directly on top of the broken file. This can push it deeper and you can lose patency. If this happens, you will have to regain patency by going back to the smallest file you initially used. If the file is visible at this point it is sometimes possible to use a small tipped ultrasonic instrument or ¼ turn withdrawal-type handpiece (AET - Canal Finder) to dislodge and remove it. DO NOT TRY TO REMOVE A BROKEN FILE BY USING ANOTHER ROTARY NI-TI IN AN ATTEMPT TO LOOSEN IT - YOU WILL JUST BREAK THE SECOND FILE AS WELL.
There is one hard and fast rule for file removal: If you cannot CLEARLY see it visually - you should not attempt to remove it. Like it or not, this means using a Surgical Operating Microscope in almost all cases. Hoping to dislodge it by working "blind" invariably will results in making the situation worse through perforation or compromise of the root dentin. In order to attempt file removal, a staging platform is created with a specially modified flat-ended Gates Glidden bur. This platform needs to be clearly visualized. It creates a flat area of dentin surrounding the file fragment. Small tipped Ultrasonic instruments (See last month's Fax) are used to trough around the instrument and eventually vibrate the file out of the canal. The tip is used in a counter clockwise motion (opposite to the way the file was turned when it broke) to loosen the file. Irrigation combined with ultrasonics can frequently flush it out at this point. If sufficient file is exposed, an instrument removal system (such as Tulsa's IRS or Masserann kit) can be tried. My experience with them has been mixed. Many times the root is thin and a lot of dentin has to be removed to get the tube to properly seat over the instrument so it can grab. It is very easy to strip perf a curved canal when trying to get these instruments to fit. A second method is to use a similar tube, this time with core paste. The tube inserted into over the exposed file fragment and the core paste is allowed to cure. The tube is removed and (hopefully) the fragment is embedded in the hardened paste. The key is getting the tube to seat over the file fragment- not an easy task.
Surgical Treatment :
For broken files that are "behind the curve" this is often the only way to treat the case. The problem is that the file fragment is not visible because of the curve of the root OR so much dentin has to be removed to allow for visualization that strip perforation is almost certain. This is most common in mesial roots of mandibular molars curved MB roots of maxillary molars and maxillary first premolars. END