How to remove a broken instrument from the root canal
Removing the tool from the ducts
Mistodent Dentistry performs operations on the extraction of fragments of endodontic instruments from root canals under the microscope. We offer an affordable price and a very efficient procedure. During the therapeutic procedures, the dentist uses both manual and machine endodontic instruments. Each of them has its own purpose and peculiarities of operation. However, in spite of the high quality materials, every tool can break. No doctor is immune to this situation. Removing the fragment from the root canal. One of the most difficult problems in endodontics.
Fracture of the instrument in the root canal causes:
- Violation of the method of work;
- Complicated anatomical structure of root canals;
- Incorrect speed of rotation of the instrument;
- Tool wear and tear;
- The fragility of the instrument;
- Putting a lot of pressure on the instrument.
This situation can happen to any dentist. This is a difficult problem for the dentist, because when working in the root canal, it is not always possible to see how and where the splinter is located. Today, broken instruments can be extracted using several techniques.
The difficulty in the extraction of the fragment of a dental instrument from the root canal depends on several factors:
The precise need to retrieve the instrument breaks occurs when the broken instrument blocks the path to infection, or when it is the source of the infection. If the broken instrument in a root canal with inflammation is not extracted, further treatment will be impossible or ineffective and the tooth will have to be extracted.
Today an endodontic microscope, a set of modern equipment and special devices are used for work. With the right approach it is possible to detect and remove the fragment in 90% of cases. This is a high figure, because the result of extraction depends on the location of the fragment, the width of the root and other aspects.
If the instrument breakage in the root canal is in the mouth or middle third of the canal, it can be removed in most cases. The situation is more difficult if it is in the apical area (the most difficult area to access)
How to remove the instrument from the root canal?
In modern dentistry doctors use very thin instruments. Their diameter is a hundredth of a mm. That’s why it might happen that the instrument breaks during the work. There are several reasons for this.
If the broken instrument covers the lumen of the root canal, the root canal cannot be properly cleaned, treated with antiseptics. This situation is very serious because the patient can get an inflammatory process at the root apex, leading to purulent aggravation and even tooth extraction. A modern microscope is used for the work, which allows to extract the broken instrument under magnification and then fill the root canal lumen.
Our clinic is staffed by professionals who are specialized and experienced in the extraction of bone fragments. In addition, the doctor uses a powerful magnifying technique (microscope) to eliminate unsuccessful treatment attempts. As a result, a filigree operation is performed quickly to extract the broken instruments from the root canal.
The use of a microscope allows for the most precise work. As a result, the doctor preserves the tooth tissue as much as possible and increases the likelihood of a complete cure. All manipulations are painless and safe for the patient.
Today the endodontic microscope, a set of modern equipment and special devices are used for the work. With the right approach, it is possible to detect and remove the splinter in 90% of cases. It is a high indicator because the extraction result depends on the location of the fragment, the width of the root and other aspects. Chernousova E.А.
What affects the success of the extraction?
- The site where the fragment is located;
- Type of instrument;
- Length of the fragment;
- Depth of localization;
- The stage of clearing when the problem occurred;
At our clinic in Kharkov you can get a wide range of endodontic services. We employ professionals capable of obtaining effective results in the most complex cases.
Fracture of Endodontic instruments in the root canal. A very unpleasant situation, but there is a way out of it as well. Main. Consult an experienced dentist. Only a doctor with a high level of professionalism and specialized manual skills can extract the fragment, and a microscope (magnification) and special instruments are needed for this.
We have a huge range of endodontic instruments at our center, as well as a specialized set of Terauchi instruments for the extraction of fragments from root canals. We guarantee effective treatment and quality service. Reviews of this procedure can easily be found online, where patients share their treatment stories.
Comparative analysis of the different techniques used in the extraction of endodontic instrumentation fragments from root canals
Evaluate how well certain techniques used in the removal of instrument parts from different levels of curved and straight canals work.
Tool removal was attempted on sixty-three straight and thirty curved root canals that contained pre-fractured tool pieces. Ultrasound was used under the observation of the operating microscope; also the result was achieved by traditional methods. The Masseranna kit was also used in straight canals and root canal instrument removal. The removal of the instrument fragment or the provision of a permeable canal cavity was considered a successful treatment.
As a percentage, when working in curved root canals using ultrasound, success was achieved in 93.3% of cases, compared to only 66.6% when using traditional methods. With straight root canals, also with ultrasound, the success rate is high, at 92.5 percent. The traditional method had the next best result (80.9%), with the Masseranna kit having the lowest success rate (47.6%). When identifying the most successful method of work in the root canals, depending on the position of the proverbial instrument parts in them, the lowest success rate was found in the apical third of the root canal.
The location of the instrument fragments and the shape of the root canal affect the success of removing these fragments from the root canal. It has been proven that the use of ultrasound under the operating microscope makes the removal process more efficient.
The use of nickel titanium rotary instruments in endodontic practice has been popular and retained over the years; new instruments and techniques continue to be developed in dentistry. However, the use of nickel titanium rotary instruments, although effective, creates a high risk of instrument failure during treatment. This can prolong the duration of root canal treatment, which can lead to negative consequences.
When instrument failure occurs in the root canal during the preparation procedure, the physician must evaluate further treatment options, taking into account the condition of the gums, root canal infection, root canal anatomy, position and type of broken instrument, and assess the amount of damage that can be caused to the remaining teeth. In this case the doctor may prefer to remove the broken part of the instrument or seal the fragment in the root canal cavity space. Predictions for cases in which the choice is either to remove the instrument fragment or to leave it in the root canal. are described in the literature.
Currently, there is no single procedure that can be used to safely and successfully remove instrumentation fragments. However, the removal of fragments with the old traditional methods is time-consuming, rather risky and not always successful. Currently, removal of broken instrument parts is performed using ultrasound, surgical microscopes, or microtubing.
Special ultrasound handpieces have been developed to increase the safety and success of the procedure. They vibrate to loosen obstructions, thus causing minimal damage to the walls of the duct. Operative dental microscopes also play an important role in the removal of instrument debris. Illumination, broadening of vision and zooming in on the root canal using a microscope allows doctors to see the fractured instrumentation in detail and remove it without peorizing. This technique uses to create a platform with ultrasound instruments around the broken fragment, followed by exposure to ultrasound vibrations in combination with an irrigation solution. All procedures of this technique are performed with an operating microscope.
The Masseranna kit (Micromega, Besançon, France) are hollow tubes designed specifically for removing intracanal metal objects such as instrument fragments, silver tips and dental posts.
This technique has been used for 40 years as an instrument debris removal kit and its success rate for anterior and posterior teeth is 73% and 44%, respectively.
The success of non-surgical removal of a broken instrument from the root canal depends on the anatomy of the canal, the location of the fragments in the canal, their length, diameter and curvature of the canal itself, as well as the compression of fragments by the canal walls. Instruments that are in the straight part of the root canal, as a rule, can be easily extracted. If parts of the broken instruments are partially along the curves of the canal and direct access to them is possible, they can be removed. Removal of broken parts that are located in the apical part of the curved canal is usually almost impossible.
The aim of this study was to evaluate the success of methods that can be used to remove broken instrument parts from straight and curved root canals at different levels.
Material selection and preparation of the teeth.
The present study included 63 extracted anterior teeth with single straight roots and 30 mandibular molars with intermediate roots and curvature of 5 and ? 20. Cavity access was created and the gingival tissue was removed. The working length was determined with a K file (MANI Inc., Utsunomiya, Japan) in each root canal.
The remnants of the instruments in the root canal.
04 Heroshaper cone (Micro-Mega, Besançon, France) and rotating instruments in the curved canals and # 25K file (MANI Inc., Utsunomiya, Japan) in straight canals were used as broken instruments. Instruments were notched with a toothed boron edge at 2.5 mm from the tip, which contributed to the notch at a given length. Straight root canals of anterior teeth (number of 63).) and curved canals of mandibular molars (numbering 30 pcs.) were divided into 3 subgroups based on the location of the instrument fragment in the apical, middle, or coronal third of the roots, contained in 21 straight and 10 curved canals, respectively. Rotating tools with a notch worked at different pressures to break the tool and position the debris at three different levels of the canal walls. The molars were then examined with a radiovisiograph on the cheek-lingual side, and the unicondylar ones on the mesiodistal side.
Instrument debris removal technique.
Broken instruments in curved canals were removed traditionally and using ultrasound. In straight canals, instruments were extracted both traditionally and with ultrasound and a Masserann kit.
Traditional method. Access to the damaged instruments was achieved using the Gates-Glidden drill, then K file was used to free the debris under the control of the operating microscope.
Ultrasound. First, access to the damaged areas was achieved using Gates-Glidden, then ultrasound tips were used (ProUltra ENDO Tips, Dentsply Tulsa Dental, Tulsa, Oklahoma), which were attached to the base (EMS, Nyon, Switzerland), then an examination was performed using a microscope (Global Surgical, St. Petersburg, Russia). Louis, MO). A diamond-coated ultrasound tip (type 1-5) was used to loosen the broken pieces and then a vibrating ultrasound tip (type 6-8) was used to remove the fragment directly.
Masseranna kit was also used to remove the fragment (MicroMega, Besancon, France). The area around the end of the fragment was treated with trepanation drills of different diameters. Two different sized extraction devices (1.2 and 1.5 mm in diameter) were inserted into the cavity in order to capture and remove destroyed fragments from the root canal.
Complete removal of the broken instrument fragments was considered successful, or the cavity was made permeable without perforating the root canal.
Speaking of success, the following should be noted: 74 of 90 instrument fragments were successfully extracted, or the root canal cavity was vacated. As a percentage, that means 82.2%, unsuccessful attempts, respectively 17.8%. Success rate with ultrasound 93.3%, and traditional methods only 66.6% when working in curved canals (Table 1). In the direct channels of the Masseranna set, there was success in only 47.6%, ultrasound 95.2%, traditional methods 80.9% (table 2). The success rates of ultrasound and traditional methods far exceed those of the Masserann kit.
Regarding the success of debris extraction depending on its location, it was found that debris located in the coronal parts of the teeth, regardless of the curvature, was extracted completely by all methods. In the middle of the canal, 16 of 21 in straight (76.19%) and 9 of 10 (90%) in the curved canals were extracted, but in the apical third only 15 of 21 in the straight and 5 of 10 in the curved, a percentage of 61.9% and 50% respectively.
Before removing tool residue, many factors must be taken into consideration. Generally, the odds of a successful procedure are equal to the odds of failure. There is no single procedure for removing residual instruments from the root canal. Any prior instrumentation and procedure technique may be considered imperfect. As mentioned, the Gates-Glidden boron was designed to create a site and when applied ultrasound to the destroyed parts of the instruments, as described by scientist Riddle and tested by Ward’s group. Word concluded that the ultrasound technique of removing rotating nickel-titanium elements from narrow and curved root canals is the most effective in most clinical cases.
The Masserann kit has served as a device for removing instrument debris from root canals for over thirty years. This system is still applicable and effective today in some cases where, for example, tool debris is in a convenient position to retrieve it. On the other hand, it is difficult to use this kit to remove debris from posterior teeth, as well as from thin and curved canals. Researcher Yoldas and his team believe that using the Masseranna kit increases the risk of root canal damage. Scientist Friedman and his team also believe that the Masserann kit is inferior to ultrasound.
Studies have shown that the success of removing instrument debris from the root canal without negative consequences depends on the type of debris that has broken off the instrument, the anatomy of the canal, the degree of its curvature, and of course, the extraction technique that the doctor chooses.
Scientist Word and his team believe that it is much easier to remove debris from hand-held dental instruments than from rotating nickel-titanium instruments, because their debris can occupy a small area, create additional pressure on the walls of the curved canal, due to their elasticity they can be pulled along the canal.
In the present study, tool size #25 was used as a broken tool.04 and 2.5 mm in length, since these are the most commonly used instruments with these diameters. Rotating Heroshaper instruments were presented in this study because there are no studies in the literature on the problem of retrieving broken instruments of this particular type.
Rotating systems were used to solve the difficult problems of treating curved root canals, while conventional hand instruments could easily be used to treat straight root canals. For this reason, K files were used in straight canals, while Heroshaper instruments were preferred in curved canals. Removed teeth rather than plastic blocks were used for the studies, because the heat radiated by the ultrasound device can melt the resin and the efficiency of the ultrasound tips can be reduced. The use of extracted teeth also allows for better ultrasound performance in most clinical cases. In the present study, medial-tongue curved canals were considered because they are often the ones where instruments break.
Dr. Jeschen and his team proved that the success of instrument debris removal depends on the type of teeth. Drs. Jeschen and Schinkel presented a paper on how canal size and root canal irregularities affect the success of extracting instrument debris. In their report, they proved that the success rate of debris removal was higher in straight and wide canals of the upper teeth than in curved and narrow canals and mandibular teeth.
When tooth debris removal has been proven to be effective depending on its location in the dental canal, there has been a one hundred percent success rate in extracting it from the coronal third of all canals. These findings were made with the cooperation of Dr. Ward and others. Studies by Drs. Hulman, Schnickel and Nagai showed rather poor results; it was found that the work was least effective in the coronal third. In collaboration with our research, Dr. Sauter and colleagues released a scientific report on the low success rate in removing instrument debris from the apical third of the root canal. Even with a microscope, it was quite difficult to remove debris from the apical part of the distorted canal. However, Sauter does not claim that all is hopeless in this case. Fors and Berg suggest that instruments should be left in place and not removed from the apical third, because attempting to remove debris from there would necessitate drilling the root canal, worsening the prognosis for root canal treatment.
In this study, ultrasound was demonstrated to be successful in straight canals in 95% of cases, in curved canals in 93.3%. The effectiveness of traditional methods and instruments shows a success rate of 66% in curved canals and 80% in straight canals. The study confirms the fact that the use of ultrasound and the operating microscope significantly improves the success of removing the instrument debris from the root canal, contrary to the traditional methods. Hulsman and Schnickel reported that the efficiency of debris extraction in their study is between 55% and 79%. Yashin’s work is down to only 53% and Ward’s study is down to 67%. In this paper, the overall percentage of instrument debris retrieval efficiency is determined to be 82.2%, a much higher percentage than in the last report, which proves that medicine does not stand still.
The location of the instrument debris and the anatomy of the root canal influence the success of debris extraction. The most effective method today is the use of ultrasound in conjunction with microscopic observation.
The Marmara University Research Committee has been looking into this.
Broken instrument in the root canal after treatment?
Questioned by the dentist and endodontist, co-founder of the Ukrainian endodontic community Denis V. PODILCHUK
Denis, on the website of your clinic I found a surprising review left by a patient. He thanks you for pulling two instruments out of his root canal! I did an Internet search and realized that your patient is not the only one who has had this problem. But how could it be that there was a dental instrument in the root canal, and what exactly it was??
Tooth canal looks like a tunnel. To clean it, the doctor uses tools made of medical steel or of a nickel-titanium alloy. But no matter how strong the metals that are used for dental instruments are, they are all subject to what is known as fatigue. And if the doctor doesn’t use a new instrument, handles it incorrectly, or the root canal is very bent, the instrument can split apart.
That is, it can break right inside the root canal?
Yes. Statistically, the incidence of such breakage is 2-5% of clinical cases. A broken dental instrument by itself does not cause inflammation, but it is caused by microbes that are in the root canal, and the breakage prevents it from being cleaned properly. But only in half of all cases does a broken instrument cause problems. Often people live with these chips in the root canal without even knowing it and they don’t have any inflammatory symptoms.
And how can a person guess that there is something left in his dental canal??
Usually you can judge about it by the X-ray image that must be taken according to the protocol of root canal treatment (endodontic treatment) after the end of the root canal treatment. I also often see instrument debris through the microscope during dental treatment. Once such a fragment is found, it can be photographed, extracted and shown to the patient.
That is, if a person has treated dental canals and wants to make sure that the doctor did not forget anything there, you need to take a control X-ray?
Example: A picture of a dental canal before treatment, with instrument fragments, and after they are removed.
The protocol you mentioned is only used in your clinic or in all medical facilities?
This is the protocol recommended by the Ministry of Health, but it’s already outdated. Therefore, we are guided by the current protocol, which is the gold standard of endodontic treatment. Before and after pictures are a prerequisite for quality dental canal treatment.
And if the dentist does not have the right equipment to take pictures?
If the dentist does not have the equipment to perform the protocol recommended by the Ministry of Health, it is a violation of the treatment standard. Correspondingly, the potential for errors and inaccuracies in this case is much greater. It is not recommended to perform the treatment in places where there is no possibility to take pictures and control the quality of the doctor’s work.
Suppose a person went to one doctor, and then went to another and found that the previous doctor had left a broken piece of dental instrument in the root canal. What to do in this case?
The dentist, whether a specialist (endodontist) or a general dentist, must first analyze the clinical situation and, after a comprehensive evaluation, tell the patient whether the instrument fragment needs to be removed. If an inflammation is found, the doctor must offer to treat the tooth canal again: open it, go through it again, remove the chip and put a filling. In certain clinical situations, when nothing is bothering the patient and there is no inflammation, it is not advisable to remove the chip, because the tooth could be damaged and making it worse.
And, if you leave it as it is, a person will not feel anything?
Still, a broken dental instrument in the root canal is a relatively safe situation or a ticking time bomb?
Broken instrument is always a complication. However, dentists say: “He who doesn’t break the instrument doesn’t work. These situations have been, are and will continue to occur. At the same time, this does not mean that the dentist should not minimize such complications.
Should a doctor who treats dental canals give a warranty on his work?? And if so, how can patients find out about it??
First of all, the doctor should try to minimize risks in his work. In our clinic, in addition to control X-rays and the use of a microscope for root canal treatment, we also keep a record of the instruments used. We prefer to replace the instrument with a new one if there is the slightest doubt of its “weariness” and therefore there is a risk that it could break. Single use of dental instruments for the treatment of dental canals is not common in Ukraine: Taking into account the high cost of instruments, it would increase the cost of treatment up to 1.5 times. A year ago we did a survey in our clinic and 83% of the patients admitted that they were not willing to pay for a customized kit. Nevertheless, there are those who want a new set of dental instruments used for their treatment. We are certainly open to such requests.
Dental canal treatment is a microsurgical procedure. It, like any surgical procedure, has a prognosis rather than a guarantee. When you have your appendix removed, you will not be given a 100% guarantee of success. And there are risks with nerve extraction, too. The outcome depends not only on the doctor, but also on the patient’s immunity, the type of germs living in the root canal, and the anatomy and condition of the tooth. The favorable prognosis usually varies from 80% to 95% depending on the situation.
What other situations do you encounter?? What are the most common problems?
About 70% are simple situations when the tooth canal needs to be re-treated, and the remaining 30% are complicated cases. With these, the patients are most often referred from other clinics. At the top of the list are missed root canals. Without proper magnification (using a microscope during treatment) the doctor misses 20%-30% of root canals.
And why does the doctor miss the root canals??
Human anatomy is very individual. Some people might have one root canal, but others might have three or four. And treatment without magnification (without a microscope or binocular magnifying glasses) is done, so to speak, by feel or almost blindly. And thanks to the magnification the doctor can better see the anatomy of the tooth. Believe me, the entrance to the canal can be so small that sometimes it’s hard to find even with a microscope.
How do you solve this problem in your clinic??
At our dental clinic, we always treat dental canals under the microscope, because it allows for a better cleaning of the root canal, minimizing the risks and therefore achieving greater success.
What other complications do you encounter besides missed root canals and broken dental instruments??
Often refer patients with sclerosed canals. Due to inflammation, the dental nerve tries to wall itself up in the root and thus thinning the root canal. Doctors who treat it without magnification run the risk of not going along the root, but piercing the tooth wall and getting into the bone, which in turn leads to new inflammation. As a result, the tooth canal will not be found and passed, and the tooth will become a constant pain. In our clinic such problems are successfully solved.
If we talk about unusual situations, what else can be found in the tooth??
In my practice I have repeatedly found absorbent cotton. It could stay in the canal of the tooth for five years or longer, causing inflammation. And the absorbent cotton was both directly under the filling and at the very end of the tooth canal, in the bone. How it got there is anyone’s guess.
There are also quite a few foreign bodies. There were cases when instead of standard dental pins we found non-standard pins that are not used in dentistry at all. the usual construction wire. Or instead of a post, a drill used to prepare a tooth for a filling.
That is the boron used to drill the tooth?
Yes, they took a piece of metal boron and put it in the tooth. Also, patients are often sent to us when they can’t get a post. The thing is that after the root canal treatment, some of the teeth need restoration with pins, and if the treatment was done poorly or had a complication, we have to take them out. Some kinds of posts are impossible to reach without magnification, but thanks to the microscope we can do this very well.
Frankly speaking, I was very impressed with what I heard. Advice on how to choose the right doctor for root canal treatment?
The first criterion for choosing any dentist is trust, and the dentist is no exception to this rule. If there is no trust, then this is not your doctor.
Choosing a clinic, ask your friends and acquaintances about their reviews, but do not limit yourself to them, because the doctor may not have a high professional level, but people like him, and then they will recommend him. Or, conversely, the doctor may be a top-notch professional, but not able to communicate with people. So recommendations are only half the information you need to make an informed decision.
You also need to make sure that the clinic you are going to is really a good one and uses proven modern technology. I recommend to find half an hour to read the information on the Internet (e.g. on the website of the clinic), and ask on site, than fill the root canals and how it happens. To paraphrase the old Latin saying, “Warned is armed,” we can say, “Informed is prepared. Be well!
Made of a highly flexible, wear-resistant nickel-titanium alloy (56% nickel and 44% titanium). The bending of the root canal over 250 is an additional challenge for traditional K-hand instruments and thus requires the “Step Back” technique. The tip of the nickel titanium tools is able to bend at an angle of 900! It is necessary to point out that the creation of the machine profiles required a radical change in the design of the working part of the tool. Thus, the traditional ISO tool size increase could not be used for machine profiles because the tool diameter increase from smaller to larger tool size in traditional files and rimes is up to 50% for smaller tools and 16% for larger tools. Going from one size to the next put a lot of strain on the tool and risked breaking it. Such an increase in machine profiles would almost inevitably lead to jamming and complications.
Therefore, the real correspondence of the tool number and the true size of the tool is disturbed when creating the profiles on the basis of scrupulous, including mathematical, research.
Profile tip size depending on the number (according to ISO)
|NN, (according to ISO)||15||20||25||30||35|
|Real size of the tip of the profile||0,13||0,18||0,22||0,28||0,35|
All profile numbers are characterized by a 29% increase in diameter from smaller to larger, compared to the previous number, which ensures a smooth transition from size to size and prevents the instrument from jamming in the canal.
Standard hand tools have a 2% taper, meaning that the diameter of the tool changes smoothly from base to tip by 2%. Taper of available profiles is different. 4% or 6%, which is usually recorded as 04. or 06. Increasing the taper firstly increases the strength of the tool and makes fracture in the channel less real. Secondly, the increased taper allows immediate, effective removal of the softened dentine at the root canal mouth, giving it a more immediate and optimized shape, expanding the crown and ensuring better access to the apical part of the canal.
As can be seen in the picture, the cutting edge of the instrument makes little contact with the root canal wall and this virtually rules out jamming. The instrument itself only takes up around 1/3 of the root canal space, leaving the remaining 2/3 to evacuate sawdust from the root canal during cavity preparation. The evacuation capacity of the dentine filings is thus clearly increased in comparison with other machine instruments that are traditionally used in endodontics. The trouble with previous tools was the ineffective removal of swarf from canals, which often resulted in jamming or considerable time wasted manually evacuating these swarf after the use of machine preparation. over, the design of the working edge of the profiles, and the presence of nickel in the alloy when the instrument jams, causes the spiral to “unroll” backwards and lengthens the instrument before it breaks away.
The safety of the preparation with profiles is also improved by the spot welding at the handle of the instrument, which usually leads to a breakage at this point and the broken instrument is easy to remove from the root canal.
Naturally the tip of the instrument has been modified, just like any other modern instrument. It is blunter and does not tend to penetrate the canal wall, t. е. Avoids the complications described in detail below.
Thus, summarizing all of the above, the following conclusions can be made:
With machine profiles, the safety of the preparation is significantly improved in comparison to other machine tools.
The efficiency of the preparation is increased sharply by the active evacuation of shavings from the root canal, due to the new design of the cutting edge.
Profiles are universal instruments that pass through, enlarge the canal and evacuate sawdust at the same time (clean the canal).
Improved abrasion resistance of the airbrush blades has been achieved. more than 10 times compared to conventional instruments.
ISO standard marking. The number (which, remember, does not reflect the actual size of the instrument) and the traditional color coding of the handles allow you to quickly and easily select the right profile.
Special units and handpieces for working with profiles were developed by Mallifer company. The optimal speed of preparation with profiles, as calculations have shown. 250. 350 rpm, and the instruments were manufactured for these preparation parameters. Special handpieces with reducer allow reducing the speed by a factor of 6 to 10 without losing any power (the angular momentum remains almost the same). So, when using a tip with the 10:1 transition at a rotational speed of 3,000 rpm specified by the unit, the profile will rotate at 300 rpm (t. е. 10 times less). Similar calculation is carried out for handpieces with 6:1 transition (instrument rotation is 6 times less than set by the machine).
Initially, it is recommended to insert the profiles up to the middle of the working length, that is, to use the technique “from the crown downwards”, which provides a wide, conical access with smooth walls, which greatly facilitates manipulation in the apical third of the canal, preparation of which is recommended by the standard technique “Step Back”. “step back”. The use of profiles considerably reduces preparation time.
Here is the Mallifer Instructions for Use of Profiles 04. They should be used at speeds between 150 and 350 rpm. For power and speed stability we recommend using geared handpieces which, while reducing rotational speed, do not reduce the power of angular momentum.
As no two root canals are identical, surgical procedures are carried out taking into account the individual topography of the root canals. The methods described below are appropriate in most cases, but are advisory in nature.
First a diagnostic X-ray is taken and the working length of the root canal is determined. Additional apical openings and canal types are identified. After that the 04 profile. N25 (with red marking) at a speed of 250 rpm is introduced to a depth of between 1/2 and 2/3 of the working length of the canal, applying light pressure on the instrument (comparable to the pressure on a pencil when writing), until resistance appears. (The sensation is comparable to the resistance encountered with hand tools as well.). The instrument is then withdrawn. After each procedure examine the instrument for deformation, and if it is present, the instrument is replaced.
The 04 profile is then inserted into the root canal. N30 (blue) to approximately the same depth as the previous one.
After that the profile N20 (with yellow marking) is inserted into the root canal not further than 3/4 of the working length.
Then use a hand bent K-file or a nitiflex file (N10-15) to precisely determine the working length with an apex locator or a radiograph and fix it with a silicone stop on the profile 04. N15 (with white marking). Then push the profile into the root canal with very light pressure on the working length. If when inserting the file there is a considerable resistance before reaching the full working length, repeat the previous steps of the root canal processing (profiling N25, N30, N20) as described above.
Before profiling is sufficiently profiled or in very calcified root canals, the last 2 or 3 mm up to the apical opening should preferably be prepared with a hand instrument or with a special hand profiled holder.
After reaching the working length with the profile N15, successively larger tool sizes (N20, then N25, etc.) are applied. д.) with very little pressure and widen the apical third of the canal. The size of the final instrument depends on the size of the root canal. After this preparation the root canal takes a gradual narrowing of the shape from the orifice to the apical opening.
If there is a greater expansion of the root canal (for example, in some techniques of root canal filling), either the “step backwards” technique or Gates or ultrasound assisted preparation systems are used in addition to the profiles. Mullifer recommends the use of the 06 profile in such cases.
During the preparation it is recommended to use abundant, frequent washing of the canal with 2.5% sodium hypochlorite, as well as to check periodically the permeability of the canal up to the apex, using small K-files of the full working length.
Another standard preparation procedure, recommended by Mallifer, involves the combined use of the 04 handpiece. и 06.
First with profile 06. N25 pass 1/5 of the working length. 1/2 of the working length of the root canal. Then use Profiles 06. N20. 2/3 of the canal. Then move to the profile 04. N25 and 3/4 of the working length of the root canal, using the 04 N20 profile. N20. entire canal, not reaching the apical constriction 2. 3 mm. Then, with profile 04. N15. for the whole working length, and then we finish the root canal with profiles 04 for the whole working length. N20 and 04. N25. We finish the preparation with Profiles 06. N 20.
The root canal prepared this way is ideal for use with the Thermafil filling system.
In addition, Mullifer also produces profiles with a taper of 02. Profile 02. The N15 can be used in narrow root canals after probing and establishing the full working length. There is always the risk of apical constriction, so we do not recommend the widespread use of Profiles 02. N15.
Instrument breakage in the root canal. medical article, news article, lecture
Tool breakage during root canal preparation is not a serious complication in itself. However, aspiration or swallowing of an instrument fragment should be considered a serious complication. A loose fragment that protrudes into the tooth cavity can be grasped with forceps, clamps or other instruments and can usually be extracted without difficulty. It is not possible to remove a jammed fragment in this way. If the end of the fragment is below the mouth of the root canal, it cannot be grasped in this way. The use of chemicals designed to dissolve the root canal wall is ineffective.
For the removal of fragments from the root canal of the rod instruments with success use the domestic set (picture ), consisting of:
A free bone fragment that protrudes from the root canal can easily be removed with beak forceps (Fig. ). In such cases the fragment wedged in the root canal is removed using a collet instrument, which allows to overcome a certain force during the extraction. If you cannot grasp the fracture, you can access it by drilling out the hard tissue around it with a boron-trap (picture). The extraction of wedged fractures is also easier with a boron-cracker. Fragments remaining in the middle and apex part of the root canal, as a rule, cannot be extracted.
If the instrument cannot be extracted by the methods described above, you can try to pass near the fracture with a drill or drill bit and by pulling on yourself, pressing the instrument firmly against the fracture, try to extract it. If there is no effect it is recommended to perform electrophoresis of the root canal (EFC) with potassium iodide (in single-rooted teeth) or with 5% alcoholic iodine solution (in multi-rooted teeth) and fill the permeable part of the canal with zincoxy-eugenol paste. Sometimes it is possible to go to the apex of the root next to the break, expand well and fill the root canal. If the end of the fragment protrudes beyond the apex into the periapical tissues and if there are clinical indications it is necessary to try to extract the fragment through the gingival incision and trepanation opening in the jaw. If it cannot be removed, the root apex must be resected (for maxillary single-rooted teeth). If there is a tool fracture in one of the roots of multi-rooted teeth and the apex of this root is incised, a hemisection or coronadicular amputation can be performed. In some situations, if indicated, a tooth extraction followed by insertion of a Hi-Tec or Straumann Bone Level implant is necessary.
It was found that in cases of root canals with a broken instrument the prognosis is favorable in root pulp extirpation and in depurpated teeth without an incision area at the root apex, while in cases where an incision area exists before treatment begins the prognosis is favorable in less than 50% of patients (Grossman, 1969).
Instrument Fracture and Extraction: Two Clinical Cases
Every endodontist encounters the problem of a broken instrument in the root canal. The task of extracting a broken instrument from a root canal can be quite a challenge. Clinical outcomes of instrument fracture treatment depend on a number of factors, including instrument placement in the canal, material type, instrument size, and anatomical structure of the canal. Failure to retrieve a portion of the file does not necessarily mean failure. You can try to bypass the broken part, have it surgically removed or even just leave it as it is and monitor it dynamically. However, in any situation we should at least try to remove the instrument breakage from the root canal.
Clinical case 1 A 27-year-old female patient was referred to our clinic. American Society of Anesthesiologists (ASA) score was 1. The patient was concerned about pain in the area of the tooth 46. Examination revealed instrument fracture in the apical portion of canal 46, diagnosed as chronic periodontitis, whereupon it was decided that the instrument should be removed prior to repeat canal endodontic treatment. Before the treatment, a new diagnostic radiograph was taken that revealed two file fragments, one in each of the medial canals The tooth was isolated with a rhabberdam, the crown filling was removed and then direct access to the canal was ensured: the latter is a prerequisite for the detection of instrumental fragments. Gates-Glidden burs (DENTSPLY Maillefer) were used to enlarge the medial canal mouth. Once a file fragment had been exposed in the medial-cheek canal, I modified the Gates-Glidden No3 bit by removing the tip of the instrument. At this stage, a breakage of the instrument in the root canal was clearly visible. ProUltra ultrasound tips (DENTSPLY Maillefer) in zirconium nitride and titanium were then used to release the file fragment.
After 1.5 hours of the procedure, there was a positive trend, but the file fragment still could not be extracted from the root canal. We decided to leave it in the canal for some time and scheduled a follow-up visit. A calcium hydroxide paste (UltraCal XS, Ultradent) was injected into the crown portion of the medial canals, then the tooth was sealed with glass ionomer cement (Fuji IX GP Fast, GC) and covered with a cotton swab. During the second visit, the tooth was isolated and opened again. The calcium hydroxide paste was removed with 10% citric acid and a passive ultrasound treatment with IRRISAFE handpiece (Satelec). The ultrasound instruments were used again to locate the instrument part. After 5 min, the instrument fragment that was in the medial-cheek canal was removed. After another 5 min, we extracted the file fragment from the medial-lingual canal as well. While it took a long time to remove the fragment from the medial-caudal canal, extracting the file fragment from the medial-tongue canal was surprisingly easy. This example only confirms the above-mentioned variety of levels of complexity of this procedure. After extraction of the fragments, the medial canal length was determined using an electronic apex-locator (Root ZX Mini, Morita). A conical lumen was provided; the medial canals were shaped with ProTaper S1 (DENTSPLY Maillefer) to begin with. Abundant canal medication was performed using 3% sodium hypochlorite solution. From the distal canal with ProFile (DENTSPLY Maillefer) size 25.06 (500 min-1 rotation speed, X-Smart Easy DENTSPLY Maillefer endodontic motor) gutta-percha was removed and no chemicals were required to soften it. Canal walls were treated with a Micro-Debrider (DENTSPLY Maillefer) to remove any gutta-percha residue. The canals were definitively shaped using a ProFile of size 40.06. The apical third of the canals was shaped using K-Flexo files (DENTSPLY Maillefer). The lubricated dentin layer was removed by treating the root canals with 10% citric acid. A final root canal treatment was performed using sterile solution. The tapered gutta-percha posts were fitted Topseal (DENTSPLY Maillefer) as a sealer. The obturation was performed with a continuous wave technique using the Elements Obturation Unit (SybronEndo). After obturation, a temporary filling was placed, made of glass ionomer cement (Fuji IX GP Fast) Final radiographs were taken (Fig. 6, 7). They show homogeneously filled medial canals; therefore, extraction of the file fragments from the canals had a positive effect. A patient with a favorable prognosis was referred to her dentist for a definitive crown restoration.
Clinical Case 2 A 19-year-old patient without underlying pathology was referred to our clinic with an ASA score of 1. The attending physician broke a small instrument according to his cover letter, most likely a K-file size 10 or 15, during root canal treatment of tooth 15. Endodontic treatment was needed due to an injury the patient had suffered, which resulted in a crack and developed traumatic pulpitis. A new diagnostic radiograph was taken, which showed the presence of the file fragment approximately 5 mm from the apex The tooth was isolated with a rhabberdam, then access was gained to the canal mouth through a temporary filling placed by the patient’s dentist.
Calcium hydroxide residues were then removed using a 10% citric acid solution and passive ultrasonic irrigation. The file fragment was immediately visible due to the large width of the canal in the crown and middle third This allowed a very conservative and gentle approach. Given the position of the canal and its shape, we assumed the presence of canal branching in the apical part. Probing with small K-files made it possible to determine the position of the palatal canal.
The instrument fracture was in the cheek canal. We used a ProUltra No8 titanium handpiece (DENTSPLY Maillefer) to remove it, simultaneously performing an extensive medicinal treatment with 5% sodium hypochlorite solution. The file fragment was extracted, and after determining the working length, we proceeded to form the canals using rotating nickel-titanium instruments (Twisted Files, SybronEndo) (Fig. 10, 11). The final size of both canals corresponded to Twisted File instrument size 25.08. Because of the branching in the apex area, a small master file was chosen to form the apical constriction, which was processed with great care to avoid a new instrument breakage
Final formation of the apical third of the canal was performed using K-flexo files of size 25. Through treatment with 10% citric acid, the lubricated dentin layer was removed. Final canal irrigation with sterile saline solution. Then tapered gutta-percha posts were fitted. After treatment with sealer, both root canals were obturated using the continuous wave technique with the Elements Obturation Unit. After obturation (Fig. 14, 15) a temporary filling made of glass ionomer cement was placed, which was covered with a cotton swab; the swab was previously moistened with a mixture of alcohol and chlorhexidine and then, after placement in the access cavity, air dried. Final radiographs were taken (Fig. 16, 17). A patient with a favorable prognosis is referred to his dentist for a final crown restoration.
Broken Instrument Removal. Animation & Clinical Op Sequence: Advanced Endodontics
Conclusion It should be reiterated that extracting a broken instrument from a root canal can be a very difficult and time-consuming task. Dr. Marga Ree once said in a ROOTS Magazine forum that the SUTE of Endodontics is Passion, Perseverance and Patience. This formula is also completely true when it comes to extracting a file fragment from the canal.
A tremendous amount of peohoration
The physician must be able to assess the current situation from diagnosis, through treatment to prognosis, and be able to deal with various clinical surprises.
Endodontic treatment of the second lower molar
This article presents a case of irreversible pulpitis with symptomatic maxillary periodontitis of the second mandibular molar.
Repeat endodontic root canal treatment: pros and cons
Repeated root canal treatment is a predictable endodontic procedure. In the past, when telling patients about the prospects for re-treatment, doctors often pointed out the likelihood of failure.
Continuum wave obturation for the most accurate procedure
I invented the Continuous Wave obturation technique (CWOT) in 1986. and up to the winter of 1988-1989. used it in combination with Touch’n Heat (SybronEndo).
MB2: The most famous missed channel
A missed canal is one of the leading causes of endodontic failure. During root canal treatment, MB2 is not found most frequently among maxillary molars.
Condensation of gutta-percha in a continuous wave
In 1987, Dr. Stephen Buchanan developed the continuous wave condensation technique for gutta-percha obturation to simplify the Schilder vertical heated gutta-percha condensation technique.
Assessment of the quality of root canal filling with gutta-percha by optical microscopy and cone beam computed tomography
Despite the advances in clinical dentistry in the prevention and treatment of dental caries, complicated dental caries is a very common pathology of the dental hard tissue.
Bioceramics and adhesion: Root canal preparation for fiberglass using the single cone technique
One of the controversial topics in endodontics and restorative dentistry is the relationship between the properties of endodontic sealants and the concept of adhesion.
Endodontic treatment of the lower first molar with denticle obliterating the pulp chamber floor. Clinical Case
This article describes a clinical case of endodontic treatment of a lower first molar with a denticle obliterating the floor of the pulp chamber.
Clinical case of treatment of internal resorption of the upper central incisor root
This article describes a clinical case of internal resorption that began with the pulp and resulted in the loss of dentin and possibly cement of the root of tooth 2.1.
Regenerative Endodontics: a reliable solution
This clinical case describes a successful regenerative endodontic treatment with a follow-up of 42 months.
Broken tools. clinical decision algorithm
Breakage of endodontic instruments during root canal treatment. a complication that every endodontist faces. The reported incidence of broken instruments ranges from 0.7% to 6% of cases. Breakage of stainless steel instruments can mostly be prevented by discarding instruments with signs of metal fatigue, but breakage of nickel instruments can occur without any signs of fatigue. Single use of rotating nickel-titanium instruments reduces the chance of failure to 0.9%, but does not completely eliminate it. Common causes of damage to rotating nickel-titanium files are bending and/or twisting fatigue. Unfortunately, it is theoretically impossible to design instruments that will not break, because more flexible instruments that are more resistant to cyclic fatigue are considered less resistant to torsional stress and vice versa.
Removal of broken instruments is a common approach in endodontic practice. The use of the operating microscope makes it possible to reach the expansion of the root canal to the level of the broken instrument and then remove the fragment using ultrasound handpieces and/or some kind of gripping equipment.
The frequency of successful removal of broken instrument fragments is high, but can it be interpreted as a successful endodontic treatment? An immediate adverse effect of dentin extraction can be peorotation or peorotation in the hazardous area. Removal of healthy dentin and especially pericervical dentin reduces root strength and is a predisposing factor to vertical root fracture The first principle of medicine. do no harm, remember that. The goal of endodontics is to treat or prevent apical periodontitis. The most common cause of periapical lesions is an intra-root infection. A broken file by itself does not cause inflammation.
We often see teeth with broken instruments that were treated years ago without clinical or radiological evidence of periapical inflammation Periapical healing occurs if disinfection during endodontic treatment reduces the microbial load below a certain threshold. Currently, canal sterility is still a utopian goal. Apical surgery can be used without compromising pericervical dentin if a broken instrument prevents effective disinfection and the apical lesion does not heal or relapses.
The proposed clinical algorithm is based on an understanding of the biological processes responsible for periapical lesions and dental biomechanics. Its purpose. Maintaining the functionality of the tooth for an extended period of time.
Vital pulp (slightly infected canal). The location of the fragment can affect our decision:
а. The instrument is broken in the apical part of the canal:
No attempt should be made to remove the broken file fragment. It is necessary to change the working length, prepare the canal up to the fragment, use some type of NaOCl activation and obturate the canal in one visit
б. The instrument is broken in the middle part of the canal:
An attempt should be made to bypass the broken tool (Fig. 4). If bypass is not possible, it is recommended that the canal be obturated prior to instrumentation. Follow-up is mandatory, and surgery on the apex of the tooth should be considered if a pathologic process occurs after treatment.
c. The instrument is broken in the crown portion of the root canal:
An attempt should be made to remove the broken instrument with minimal dentin reduction, various types of gripping equipment can be used.
Nonvital pulp (infected case)
The stage of shaping and medication at the time of the broken file affects our decisions:
а. Instrument broken after finishing medication and mechanical treatment in this case the root canal is prepared to at least size 0.
Recommendations are the same as in cases with a vital pulp:
- Apical third of the canal: removal of the broken file fragment is usually not attempted. Obturation to the fragment is recommended.
- Middle third of the canal: You should try to bypass the broken instrument. If bypass is not possible, the canal should be obturated to the broken instrument, and then the tooth should be monitored.Apical surgery should also be considered.
- The crown third of the canal: an attempt should be made to remove the broken tool with minimal dentin reduction.
б. Breakage of instrument before full mechanical treatment and irrigation:
- Bypass is highly recommended. Canal cross-section affects this manipulation: long oval and flattened canals and isthmuses allow for this, while a round canal may prevent. If bypass is successful, it is advisable to complete the root canal by hand file up to size No extraction required.
- If the bypass is unsuccessful, a Ca(OH)2 filling of the root canal in combination with NaOCl activation for two. Four weeks. Follow-up observation is mandatory after permanent obturation. and if the pathological process develops after treatment, surgery on the apex of the tooth should be considered
Asymptomatic apical periodontitis. Instrument is broken in the apical part and in the apical area of the canal. Apical surgery. Image courtesy of Dr. Avi Hadad.
Successful removal of broken instruments can jeopardize the long-term outcome of the tooth due to loss of healthy pericervical dentin, which can lead to peoria and predisposition of the tooth to a vertical root fracture. When making a clinical decision, the physician must consider microbiological and biomechanical aspects.
The clinician must be able to assess the current situation from diagnosis, treatment to prognosis, and be able to handle various clinical surprises.
Clinical case of treatment of a peoria with calcium silicate cement and an internal matrix
Pulp chamber floor peorations can occur due to caries, iatrogenic trauma during the access creation phase, oral treatment, preparation of the pin space, or during extraction of broken instruments.
Jaya Srivastava, Manoj Kumar Hans, Rohit Paul, Amit Kumar Garg, Rhitu Shekhar Read
Lower second molar: canal-filler obturation via bifurcation
The prognosis of perioration closure has improved dramatically over the past two decades, with the use of MTA and similar cements becoming the gold standard.
Extracting broken files
Ni-Ti files break mostly in curved or narrow canals in the apical third because of their hyperelastic properties.
Author’s perspective on the problem of broken instruments
This article presents the author’s view of Dr. M. Solomonova on the problem of broken instruments from a biological point of view.
Endodontics without rules
Looking at this kind of “endodontics”, you have to wonder what you had to do to get such a final result? Let’s deal with this dilemma.
The use of ultrasound in endodontics
Choosing a system of ultrasound instruments, you need to pay attention to the possibility of adjusting the power and amplitude of oscillation.
Over Apex Expansion of Filling Materials: Endodontic Failure vs. Clinical Success
Many dentists believe that errors in daily practice, such as out of the apical opening and contact of the filling material with periapical tissues after treatment, are responsible for failures.
Detecting and bypassing the step with Explora instruments after extraction of broken instrument fragments
This clinical case will describe in detail the restoration technique for tooth 1.7 with a broken instrument in the mesial-cheek canal and a step in the middle of the root canal.
Endodontic treatment of the second lower molar
This article presents a case of irreversible pulpitis with symptomatic maxillary periodontitis of the second mandibular molar.
Repeated endodontic treatment of root canals: pros and cons
Root canal retreatment is a predictable endodontic procedure. In the past, when telling patients about the prospects for retreatment, physicians have often pointed out the likelihood of a failed outcome.
Continuous wave obturation for a more precise procedure
I invented the continuous wave obturation technique (CWOT) in 1986. and up to the winter of 1988-1989. used it in combination with Touch’n Heat (SybronEndo).
You may be surprised to know that the instrument in the root canal does not always have to be extracted. First of all, one must realize that this is a rather complicated process, which most often leads to an overdevelopment of the root canal, i.e. to an instrumental thinning of its walls.
If there is an instrument left in the root canal, we decide whether to remove it or leave it in, depending on a number of factors:
- If the instrument breaks during the final phase of the treatment, in a so-called “conditionally sterile” canal, and extraction would involve a considerable loss of tooth substance, we take the path of leaving the chip in the canal. Be sure to notify the patient!
- If we see that a chip will come out without much difficulty or unnecessary development, we will take it out.
- If we know that the broken instrument is in a “dirty canal” and that it is a hindrance to a good treatment, we will remove it.
Manipulation of the extraction of broken instruments is done with ultrasound and only with the use of a microscope. The difficulty lies in the fact that broken instruments are often very small, their size can vary from 1-2 mm. But sometimes, even magnification can’t help us if the splinter is on top of a curved canal. In such cases, if indicated, we resort to apical surgery. Removing the apex of the root along with the dissected instrument.
Scientific paper on “Removal of broken instruments from root canals
100 SCIENTIFIC NEWS |;V Series Medicine. Pharmacy. 2011.6 (111).
REMOVAL OF BROKEN INSTRUMENTS FROM ROOT CANALS
1) Voronezh State Medical Academy n.a. M.D. Lomonosov. Н.Н. Burdenko
Belgorod State National Research University
The article presents the results of the treatment of 55 root canals of different groups of teeth with instrumentation fractures and other metal fragments located at different depths of the root canals
Keywords: endodontics, root canal, instrument fragment.
Introduction. Endodontics. is a complex type of therapeutic treatment with a high risk of complications, and its performance takes most of the dentist’s working time, and the positive result does not exceed 50-70%, while patients with complicated forms of caries make up to 50% of those who applied for dental care. Unsatisfactory quality of treatment may be due to the use of outdated techniques, technology violations, low level of technical equipment, poor practical training of physicians and insufficient information on modern endodontic advances and innovations.
Of the many iatrogenic errors that lead to complications in endodontic practice, we can distinguish two main ones. Tooth hard tissue peorations and instrument fractures. Attempts to remove a broken instrument can result in “steps”, excessive dilation and movement of the treated root canal, and peorization. Therefore, the doctor must evaluate which option is preferable. Try to remove the broken instrument from the root canal, bypass it or leave the broken instrument in the canal.
The decision must be made taking into account the condition of the pulp, the degree of infection of the root canal and its anatomy, the type of broken instrument and its position in the canal.
Modern tools and techniques for the removal of broken instruments from root canals include the following:
1) the use of special clamps and forceps;
4) passing near the fracture and removing it using Microdebrider and H-file tools;
7) the technique of using a hollow needle and H-file;
9) Ultrasonic devices with RT nozzles (EMS, Switzerland), ProUltra (Dentsply, USA), Sonic Flex Endo System (Kavo, Germany), etc.;
10) A combination of the above techniques.
However, in spite of the variety of techniques and instruments that are available on the modern dental market, the extraction of debris from the root canal can be done only with the use of a specially designed device. A poorly visualized procedure requiring the use of an operating dental microscope, a considerable investment of time and patience, and yet often difficult to perform.
The aim of the study was to evaluate the clinical results of instrumental fracture removal.
Series Medicine. Pharmacy. 2011. 6 (111). Issue 15/1
Materials and techniques. The clinical studies were conducted at the Department of Dentistry of the VSMO VGMA named after M.I. Lomonosov. Н.Н. Burdenko.
The following steps were performed in strict order during treatment:
If possible, create direct access to the broken instrument with the Pro Ultra handpieces (Dentsply).
With a K-file 0, 25 mounted in an ultrasonic handpiece (Satelec, France), tried to create a groove around the crown portion of the broken instrument and/or bypass it with a K-file 0.
The broken instrument was activated using a Pro Ultra ultrasound instrument (nozzles. 5) in order to free it and remove it from the canal. Exposure to ultrasonic effects, eddy currents that occur as much as possible at the tip of the instrument to quickly create the desired space near the broken instrument.
All work in the root canal was performed with alternating 17% EDTA solution (Largal Ultra) and 5% sodium hypochloride solution heated to 50-600.
At each stage (if possible) after the instrument was released and bypassed, tried to remove it with H-files, Microdebrider or a special clamp. At any stage, if visual observation was impossible, we tried to remove the instrument under the control of tactile sensations.
If ultrasonic vibrations were ineffective, tried to remove the instrument with the Ni-Ti nozzle (Pro Ultra. 7, 8). These flexible and robust tips take the shape of the canal, reduce the risk of complications such as ledge, peoria, canal transport, and in areas with limited access work particularly accurately, easily glide along the instrument fragment without causing unwanted effects when touching metal fragments (when working with a conventional tip, contact with metal fragments can break and break the ultrasound tip itself).
Good results are obtained with a combination of manual and ultrasonic tools. As a rule, the fragment is removed and it “flies out” of the canal with turbulent flows.
Keep in mind the following effects of ultrasound when working in the root canal:
Results and discussion. As a result of the work performed, some rules for working with ultrasound tips have been formed, which, if followed, make the work in the root canal more successful.
The movements during the work with the ultrasonic tips should be light, no pressure, if the excessive pressure is applied the vibrations are dampened and the work becomes ineffective. Direction of movement is reciprocating, coinciding with the axis of canal, and circular, describing counterclockwise.
In case of the wear and tear of the nozzle there is no resonance with ultrasonic vibrations, and the work with such a nozzle becomes ineffective.
The level of oscillation power is of practical importance. it is set on the device panel and corresponds to the clinical situation. In the mouth and middle third of the canal work with larger and stiffer nozzles, at large power fluctuations such design features of the nozzles provide the transmission of more uniform vibrations and create a pronounced ultrasonic effect.
102 SCIENTIFIC VEHICLES |;V Medical Series. Pharmacia. 2011. 6 (111).
Thin endodontic nozzles are used at greater depth of the root canal, in the apical part, or in the presence of complex anatomy of the canal, using lower power values. During endonasal work, the recommended power was between 30-70% of the maximum.
In accordance with the purpose of the study, 55 root canals of teeth of different groups with fractured instruments and other metal fragments located at different depths of the root canals were treated.
As a result of the treatment performed, 28 of the 55 broken instruments were successfully removed. Accordingly, the positive result was more than 50%. In 13 cases (23.6%) the result was unsuccessful for the following reasons: root peoria and incomplete removal of the fragment.
In five roots (9%) the instrument fracture was bypassed and the fracture was incorporated into the root filling. In nine (16%) root canals, the failed instrument fragment in the apical portion of the canal became an extension of the root filling.
The location of broken instruments in the root canals is shown in the figure.
It should be noted that eight instrument fragments were so long that they filled the entire root canal (5%). All of them were successfully removed.
Two instruments were partially behind the apex of the root (2%). None of them could be successfully removed.
The study showed that the success rate may decrease with increasing treatment time, which may be due to over-expansion of the canal during ultrasound treatment, as well as physician fatigue. This, in turn, may result in a higher risk of perforations. The lower success rate can also be attributed to the complexity of the situations. Removal of broken instrumentation from the root canal should not take more than 45-60 minutes. After this time has elapsed, other treatment options should be pursued.
Conclusions. The following clinical conclusions regarding the localization of instrument fragments in the root canals and the favorable prognosis of the ongoing endodontic treatment were drawn from the study.
If the instrument breaks in the area of the mouth, removal is usually not difficult. With mechanical rotary instruments or Pro Ultra ultrasound attachments. 3 remove the dentine around the bone fragment, trying to visualize it-
Medical series. Pharmacy. 2011. 6 (111). Issue 15/1
The fragment should be removed and then removed using fine forceps or one of the specially adapted clamps.
If the foreign body is localized in the middle third of the root canal, it must either be removed, which can be quite difficult, especially if the canal is curved, or bypassed, creating conditions for medication treatment of the canal and the subsequent dense obturation.
If the fragment is in the apical third, first assess the possibility of removing the fragment and weigh up the risks associated with this procedure. In this case endosurgery may be more successful instead of retrograde intervention into the root canal.
If the fragment is tightly fixed in the apex area, it can become a continuation of the root canal, provided it is successfully medicated before the instrument breaks. В таких случаях показано длительное наблюдение.
REMOVAL OF BROKEN INSTRUMENTS FROM THE ROOT CANAL
1) Voronezh State Medical Academy named by N.N. Burdenko
The article presents the results of treatment of 55 root canals of different groups, with fracture of tools and other metal fragments located at different depths of the root canal.