Modern endodontics in dentistry. Modern endodontics – what instruments are used in root canal treatment? Instruments and apparatus

First generation

Second generation

third generation

fourth generation

Fifth generation

Protaper Next

Discussion

Conclusion

Since the advent of modern endodontics, many concepts, strategies and techniques have been developed for root canal preparation. For decades, more and more new files have appeared on the market for passing and forming channels. But, despite the variety of instrument designs and many techniques, the success of endodontic treatment was and remains only a probabilistic event.

The evolution of endodontic treatment has gone from the use of a range of stainless steel hand files and rotary instruments such as Gates Glidden to modern Ni-Ti files for canal shaping. Despite the development of modern processing methods, the mechanical aspects of working in the canal were excellently described 40 years ago by Dr. Herbert Schilder. With careful implementation of mechanical principles, the biological feasibility of processing, 3D disinfection and successful filling of the root canal system are observed (Photo 1a - 1 d).

Photo 1a. CT image of an upper central incisor showing a root canal system with multiple branches

Photo 1b. X-ray showing failed endodontic treatment

Photo 1s. Overtreated tooth with 3D cleaning of the canal lumen and correct filling

Photo 1d. Observational image demonstrating bone regeneration

The purpose of this article is to trace how each generation of Ni-Ti files has led to the development of advanced canal preparation techniques. More importantly, the authors will attempt to identify and describe clinical techniques that combine the most proven concepts of the past with the latest innovative developments.

Nickel-Titanium when working in a channel

In 1988 Walia introduced Nitinol, a Ni-Ti alloy, for root canal treatment because it is 2-3 times more flexible than steel files of the same size. The main difference of the Ni-Ti channels was that they were able to machine the most curved channels through repeated rotational movements. In the mid-90s, the first affordable Ni-Ti files hit the market. Next, the classification of each generation of files will be presented. In general, they can be characterized as tools that perform passive rather than active cutting actions.

First generation

To appreciate the whole evolution of Ni-Ti tools, it is useful to know that the first generation of Ni-Ti files had a passive radial cut and a fixed taper of 4% and 6% active blades (Photo 2). This generation required the use of a whole set of files for a complete canal preparation. Already in the mid-90s, GT files (Dentsply Tulsa Dental Specialties) became available, providing a fixed taper of 6%, 8%, 10% and 12%. The most distinguishing feature of the first generation of Ni-Ti files was passive radial slicing, which forced the file to remain centered when working in curved channels.

Photo 2. Two electron microscope photographs showing a cross-section and side view of a file with radial cuts and passive edges.

Second generation

The second generation of Ni-Ti files hit the market in 2001. The main distinguishing feature of this generation of instruments is the presence of active cutting edges and the need for fewer instruments for a complete canal preparation (Photo 3). To level out the taper block and the screw effect in passive and active Ni-Ti instruments, EndoSequence (Brasseler USA) and BioRaCe (FKG Dentaire) proposed a line of files with alternative contact points. Although this feature was added to eliminate the taper block, this line still had a taper on the active parts. A breakthrough in the industry came with the introduction of ProTaper (DENTSPLY Tulsa Dental Specialties) to the market, which created different levels of taper on the same file. This revolutionary idea made it possible to apply files of various tapers to a specific area of ​​the root canal and provide a safe and deep treatment (Photo 4).

Photo 3. Two electron microscope photographs showing a cross-section and side view of an active file with sharp cutting edges.

Photo 4. ProTaper (DRNTSPLY Tulsa Dental Specialties) the cutting surfaces are predominantly located in the upper and middle thirds of the instrument, while the final file has a cutting surface in the apical third.

During this period, manufacturers put the main emphasis on methods that increase the resistance of the file to breakage. Some manufacturers have used electropolishing to remove any roughness from the surface of the file due to the normal sanding process. However, this electropolishing has been clinically and scientifically proven to dull the sharp edges of the instrument. For this reason, for normal processing, the doctor has to apply excessive pressure to the file. High pressure on the tool leads to jamming of the tapered files, the effect of the screw and excessive bending in the process. To compensate for electropolishing, more cross-sectional options began to appear, and increased rotation speeds began to be recommended, which is also somewhat dangerous.

third generation

Improvements in Ni-Ti metallurgy have been a major development that can be identified with the advent of the third generation of endodontic files. In 2007, manufacturers began to pay more attention to heating and cooling methods to reduce cyclic fatigue and improve safety when working in more curved channels. The third generation of Ni-Ti tools is characterized by less cyclic fatigue and less breakage. Examples of brands using this technology: Twisted File (AxislSybronEndo); HyFlex (Coltene), GT, Vortex, WaveOne (DENTSPLY Tulsa Dental Specialties).

fourth generation

Another advance in canal preparation technology can be called the emergence of a technique of repetitive up-down and reciprocating movements. For the first time this method was voiced by the French dentist Blanc in the late 1950s. So far, M4 (AxislSybronEndo), Endo-Express (Essential Dental Systems) and Endo-Eze (ultradent Products) are examples of systems where the number of clockwise movements is the same as the counterclockwise ones. Compared to full rotation, reciprocating files require more pressure on the instrument, do not cut dentin as efficiently, and remove sawdust from the canal lumen somewhat worse.

Innovations in reciprocal technologies have led to the fourth generation of files. This generation has finally realized the dream of using one single file to process a channel. ReDent-Nova (Henry Schein) self-adapting file (SAF). This file is in the form of a compressible hollow tube that can provide uniform pressure on the channel walls regardless of the shape of the channel cross section. The SAF is mounted in a tip that provides short 0.4mm vertical oscillation and vibration. Also, irrigation is constantly carried out through the cavity of the file. Another single file technique is One Shape (Micro-Mega), which will be mentioned in the fifth generation.

The most popular single file technique is WaveOne and RECIPROC (VDW). WaveOne is a combination of the best qualities of the second and third generation of files, doubled by a reciprocating motor that drives the instrument. After three cycles of movements clockwise and counterclockwise, the file rotates 3600 or makes one circle (Photo 5). Such movements allow you to work more efficiently, remove dentin and bring it out of the canal.

Photo 5. WaveOne (DENTSPLY Tulsa Dental Specialities) reciprocal file having an unequal number of anti-clockwise and anti-clockwise angles, allowing more efficient work in the canal and removing dentin filings outside of it

Fifth generation

The fifth generation of endodontic files are designed in such a way that the center of gravity and the center of rotation are displaced (Photo 6). When rotated, files with a displaced center of gravity produce a mechanical movement that propagates along the active part of the instrument. Just like ProTaper Progressive Taper files, this offset file design minimizes jamming between the file and dentine. In addition, this design facilitates the removal of dentin debris from the canal and increases the flexibility of the active portion of the ProTaper Next (PTN) file (DENTSPLY Tulsa Dental Specialties). The benefits of a center of gravity design will also be discussed later in this article.

Photo 6. Cross section of a ProTaper Next (PTN) file (DENTSPLY Tulsa Dental Specialties). Notice the off-centre shape to reduce jamming and increase tool flexibility

Examples of commercial brands that offer variations of this technology are Reco-S (Medidenta), One Shape, and the ProTaper Next (PTN) file system. To date, the PTN file system can be considered the safest, most efficient and simplest tool that combines the advantages of past and present developments.

Protaper Next

There are 5 types of PTN files on the market of various lengths, marked X1, X2, X3, X4, X5 (photo 7). File handles have yellow, red, blue, double black and double yellow marking rings, corresponding to sizes 17/04, 25/06, 30/07, 40/06 and 50/06. PTN X1 and X2 have both rising and falling taper of the active part, while PTN X3, PTN X4 and X5 have a fixed taper from D1 to D3.

Photo 7. There are 5 PTN files on the image. Most root canals can be treated with 2-3 instruments.

PTN files combine 3 essential features: progressive taper on one tool, M-wire technology and the main advantage of the fifth generation - a shifted center of gravity. For example, PTN X1 and X2 have both rising and falling tapers, while X3, X4 and X5 are built with a fixed taper from D1 to D3, and in the range D4-D16, the X1 file has an offset center of rotation. Starting at 4%, the X1 file increases the taper from D1 to D11, and from D12 to D16 the taper decreases to increase flexibility and preserve radicular dentine during processing.

PTN files are used at a rotation of 300 rpm and with a slope of 2-5.2 nm, depending on the technique used. However, the authors prefer a slope of 5.2, as they consider it to be the safest for the vertical operation of the channel and the removal of sawdust from the lumen. In the PTN technique, all files are used in the same sequence according to the ISO color marking, regardless of the length, diameter and canal curvature.

Root canal technology

The PTN technique is very safe, effective and simple when attention is focused on proper root canal access and sliding technique. As with all other techniques, PTN requires strictly direct access to each orifice. The main focus is on the passage, expansion and smoothing of the inner walls of the root canal. For canal access, the ProTaper system offers an additional file called SX. The movement of this file is carried out like a brush, and it is able to expand the mouth, remove dentine triangles and, if necessary, give a clearer shape to the canal.

Perhaps the biggest challenge in endodontic treatment is finding the canal, following its course, and keeping it intact until the end of the treatment. Processing and saving channels when working with small hand files requires strategy, high skill, patience and desire. Small hand files are usually designed to locate, widen and clean the walls of root canals. After the canal is prepared manually, it is possible to use a mechanical file for canal expansion and other manipulations. To be precise, a canal can be considered finished and processed when it is clean and has strong, smooth walls.

After determining the working length, a file No. 10 is introduced into the canal lumen and it is found out whether it is possible to easily move the instrument to the top of the canal. In short, wide and straight channels, this operation is much easier. After successfully passing File #10, either File #15 or a dedicated mechanical file such as PathFiles (DENTSPLY Tulsa Dental Specialties) is applied. This file is to confirm that there is enough space to start processing with the PTN X1.

In many other cases, teeth with longer, narrower, and crooked canals are involved in endodontic treatment (Figure 8a). In such a situation, file #10 very often cannot go through the entire length of the channel. In general, there is no need to use hand files #8 and #6, just gently work file #10 over each segment of the channel until the tool starts to move freely. PTN files can be used to form any section of the channel prepared for passage. Regardless of the technique and all manipulations, the main goal is to prepare the canal along its entire length, establish the working length and find the apex (Figure 8b). The canal is considered prepared when file No. 10 freely passes through the canal, including its apical third.

Photo 8a: This x-ray shows an endodontically involved posterior bridge abutment. Pay attention to the position of the prosthesis in relation to the roots.

Photo 8b: Working image showing the opened crown, isolation and file #10 inserted, showing canal curvature.

After working with the canal, the cavity from which access was made is washed with 6% sodium hypochlorite solution. Channelization may start from PTN X1. It should be emphasized that PTN files are never used with a pumping type of movement, on the contrary, with PTN, return movements of the brush type are necessary. Using this technique, the doctor easily moves along the walls of the canal and forms the required working length. The X1 file is passively introduced into the canal through the pre-expanded orifice. Before the stop is felt, they immediately begin to move like a brush with sweeping towards the inlet (Photo 8c). Such movements help to gain additional space on the side and move the file a few millimeters deeper. Brush movements increase contact with dentin, which is especially important in canals with asymmetric cross-section and convex parts.

Photo 8c: Shown is a PTN X1 file in progress.

Work with PTN X1 continues. After every few millimeters, the file is removed from the channel for inspection and cleaning of sawdust. Prior to re-introduction of PTN1, it is necessary to irrigate and clean the canal from sawdust. Then the channel is again passed through with file No. 10 to remove the remaining particles and washed abundantly with a solution. Subsequently, one or more cycles with PTN X1 cover the entire working length. To improve the quality, it is necessary to constantly flush the canal and inspect the instrument.

After the first stage, they start working with PTN X2. Before the tool rests in the channel, cleaning movements are carried out along the walls, which allows the file to move to the maximum depth. X2 follows the path laid by PTN X1, forming the walls of the canal and extending to working length. If the tool does not go deep, it should be removed, cleaned of chips and checked for integrity. The canal should then be flushed and the instrument reintroduced. Depending on the initial data of the canal, its shape, curvature and length, one or more cycles of file insertion are required before passing through the entire working length (Photo 9a).

Photo 9a: PTNX2 is located in the mesial buccal canal.

After reaching the apex, PTN X2 is removed from the canal. A sign of the completion of the canal treatment is the filling of the teeth of the instrument in the apical part with dentinal sawdust. An alternative is to measure the hole using a 25/02 Ni-Ti hand file. If No. 25 runs tightly along the entire length, then the formation of the channel is completed. When 25/02 enters too freely, the hole is larger than 0.25 mm. In this case, file 30/02 is used, which, if densely included, also indicates the completion of channel processing. If file 30/02 is short in length, then PTN X3 is used according to the method described above.

The main number of channels is optimally formed using either PTN X2 or X3 (Photo 9b). PTN X4 and X5 are usually used to work with channels of large diameters. When the apical foramen is larger than PTN 50/06 X5, other techniques are used to complete the treatment of such large, usually less curved canals. Each canal must be neatly traversed, 3D cleaned and sealed for a successful result (Photo 9c).

Photo 9b: In the distal canal of PTN X3.

Photo 9c: X-ray after treatment. A bridge prosthesis was placed. The anatomical shape of the channels is not broken.

Discussion

From a clinical point of view, the PTN system is the most advanced and combines all the advantages of previous generations of instruments and the latest developments. A little discussion will help you understand how the design of the tool affects how it works.

The most successful generation are those that use progressive taper on a single file. The patented ProTaper Universal Ni-Ti system combines ascending and descending tapers on the same tool. This design reduces the possibility of tool jamming in the channel, the effect of the screw and work more efficiently. Compared to fixed taper files, these instruments are highly flexible, limit dentin removal, and preserve tissue in the coronal 2/3 canals. The resulting design makes it the #1 selling ProTaper file worldwide, the choice of endodontists and a technique taught in all dental institutes.

Another advantage is the material of manufacture. Although Ni-Ti files show 2-3 times more flexibility than stainless steel files, the steel industry has gained some more advantages in heating. Research has focused on heating and cooling traditional Ni-Ti alloys, both before and after processing. Heating allows you to create an optimal phase between the components of the alloy. The study showed that M-wire, a metallurgically improved version of Ni-Ti, reduced cyclic fatigue by 400% compared to a file of the same diameter, section and taper.

This development is also a strategic improvement in the clinical safety of working with the PTN file system.

The third design feature is the displaced center of gravity. There are 3 main advantages associated with such a tool device:

1. When rotated, files with a displaced center of gravity produce a mechanical movement that propagates along the active part of the instrument. The rocking effect minimizes the adhesion of the file to the dentine compared to files with a fixed taper and an undisplaced center of rotation (Figure 10). Reduced grip reduces the chance of tool jamming, screw effect and bending.
2. The off-center file design adds extra space in the cross section, which allows for better removal and removal of dentinal chips from the canal (Figure 10). The breakage of many tools often occurs precisely because the teeth of the tool are filled with sawdust of hard tissues. Also, this design minimizes the likelihood of obstruction of the canal by sawdust and disruption of its anatomy (Figure 6).
3. A file with a displaced center of gravity produces a wave resembling a sine wave (Photo 11). As a result, PTN can perform more action than other files with similar input data (Photo 6). The clinical advantage is the use of a smaller and more flexible PTN file in areas where larger and stiffer instruments were previously required (Figure 10).

Photo 10 PTN files have a progressive taper and off center design. These features reduce jamming, maximize the removal of dentine chips and increase flexibility. For comparison, the figure below shows a file with a fixed taper, center of gravity and axis of rotation.

Photo 11. Similar to a sine wave, PTNs form a wave as they move and provide a "rocking" effect throughout the working area.

Conclusion

Each new generation of endodontic files offers something useful, innovative, thus trying to surpass the previous generation. PTN, which belongs to the fifth generation, has become a unique example of combining the success of previous experience and new technological improvements. The created system is designed to simplify the process of endodontic canal treatment by reducing the number of instruments required for use.

Clinically, PTN fulfills the three main principles of channel processing: safety, efficiency, and simplicity. From a scientific point of view, further research is needed to confirm the effectiveness and identify all the important points when working with these tools.

Endodontics is a profile direction in dentistry based on. This is a fairly common area, including both standard and complex recovery after unsuccessful treatment.

Not infrequently, certain functions of the endodontist are taken over by the dentist-therapist: for example, with the well-known cleaning of the hollow space inside the root, or, in a simple way, removing the nerve.

Specificity of endodontic treatment

The beginnings of endodontics appeared in ancient Rome and Greece. The healers of that time tried to relieve patients of pain by cauterizing the pulp (connective tissue inside the tooth) with a red-hot needle.

Modern endodontics is unthinkable without an X-ray machine or a dental visiograph. With their help, each stage of treatment is visually controlled. They allow you to see the real picture of tooth restoration and, if necessary, to plan and correct surgery.

Indications for endodontic treatment are:

• sharp or;
• all forms - inflammation of the tissues around the top of the root;
• serious trauma to the tooth;
• preparation for prosthetics.

Endodontic treatment is not carried out when the inflammation of the pulp can be removed by conservative methods or, conversely, if it is impossible to restore the tooth.

Even in difficult cases, doctors try to resort to other methods of preserving the tooth: either its amputation, hemisection (restoration of the crown part with a pin) or replantation (return of the tooth to the alveolus with preservation of the root cement).

Goals facing the endodontist

A dentist who specializes in root canal treatment is called an endodontist. This is one of the most prestigious specializations in dental practice. An endodontist should be proficient not only in therapeutic treatment, but also know the basics

The tasks of the doctor of this specialization are:

• determining how necessary and successful treatment will be;
• ensuring the sterility of instruments and materials;
• separation of the diseased tooth from saliva during treatment with a latex scarf (cofferdam or rubberdam);
• high-quality removal of the inflamed parts of the pulp;
• elimination of pathogenic microorganisms inside the tooth;
• effective passage and expansion of dental canals;
• successful canal filling;
• control over the quality of restoration at each stage.

Tools used

Modern instruments for endodontic treatment must be of high quality and inexpensive at the same time, since most of them are used only once.

Modern endodontics cannot do without the following tools:

• pulp extractors: with their help, the pulp is extracted from the root canals;
• files: are used for expansion and preparation of channels;
• channel fillers: fill the root gaps with filling material;
• instruments that introduce various pastes and antiseptics into the cavity;
• pluggers: used for filling canals with gutta-percha;
• Boers Gates: Used to expand channels.

Rasp for root canal alignment

In addition, canal treatment is impossible without a number of devices:

• endodontic micromotors and handpieces: rotate the instruments inside the channel;
• apex locators: help to track the position of the instrument in the cavity and the length of the channels;
• electrophoresis, fluctuophoresis and ultrasonic devices(most often used Sonic);
• lasers, microscopes, x-ray machines and visiographs.

Stages of treatment

Endodontic treatment is a multi-stage process that requires a lot of patience from the patient and a significant amount of time. L is never done "in one sitting". Depending on the complexity of a particular case, the doctor will have to visit from 3 times (with normal canal depulpation) to regular visits to dentistry for several weeks or even months.

Endodontic therapy includes several stages:

Each stage of treatment is necessarily controlled by X-ray. Even with the usual removal of the nerve, at least three pictures are taken: before surgery, after depulpation, and a control before restoring the outer part of the tooth

The cost of therapeutic procedures

Endodontics, perhaps, can be called the most unpredictable area of ​​​​stomatology, so if during the primary depulpation of the tooth it is possible to determine the approximate prices for services and the time of treatment, then in cases of recovery from previously poorly treated canals or dislocation of the tooth, it is not always possible to accurately predict even the success of the restoration.

Endodontic treatment is expensive, regardless of the dental center. This is due to the complexity of therapy and the use of expensive instruments and drugs. Prices for tooth restoration by this method will differ not only in each area, but also in a particular clinic.

Also, the cost of treatment depends on:

• the number of channels;
• neglect of the tooth;
• the presence or absence of previous treatment;
• inflammatory processes.

Prices for endodontic treatment start from 10 thousand in regional centers and reach up to 50 thousand in large cities.

When choosing a clinic, you should focus not only on the cost of therapy, but also on the quality of equipment, the professionalism of doctors and the reputation of the clinic.

In Moscow, clinics practicing endodontic treatment are.

Yuri Maly, Polyclinic of Therapeutic Dentistry and Periodontology, Ludwig Maximilian University (Munich, Germany)

There is no doubt that endodontics occupies a royal position in dentistry. Isn't it time for this capricious queen to create her own highly structured kingdom and grow into a separate specialty known throughout the world as Endodontics? The use of the latest technologies in endodontic treatment - an operating microscope, ultrasound, nickel-titanium instruments, apex locators and others - has provided the dentist with more chances to save a tooth and achieve positive results in those clinical situations where success was impossible just a few years ago.

Endodontics is a section of therapeutic dentistry that studies the structure, functions of the pulp and periapical tissues; it is aimed at studying the physiological state and diseases of the pulp and periodontium, as well as their prevention.

In the last decade, no branch of therapeutic dentistry has developed as rapidly and successfully as endodontics. Although ancient Arab surgeons described and performed endodontic interventions as early as the 11th century, the Frenchman Pierre Fauchard wrote about endodontics for the first time in his book Dental Surgeon, published in 1728. In this book, the author refuted the then widespread theory that the cause of caries and toothache is a certain toothworm.
The first big step endodontics took in 1847, when the German Adolf Witzel used arsenic to devitalize the pulp. In 1873, Joseph Lister used phenol to treat a root canal. Alfred Gisi in 1889 created Triopasta for the mummification of the pulp of temporary teeth, consisting of tricresol, formaldehyde and glycerin.
In the mid-1940s, the era of chemical root canal treatment began. Grossman showed that sodium hypochlorite is able to disinfect and dissolve pulp tissues, and hydrogen peroxide removes pulp residues and debris by releasing atomic oxygen.
The development of endodontics for the first time gave the patient hope that the tooth could be saved through endodontic intervention. It is the question of saving the tooth that the dentist faces when the patient complains of severe pain during pulpitis or periodontitis.
Today, scientists pay great attention to the theory of pain, the effect of neurotransmitters (substance P, galanin, NO) on pain and learn to control it.

Anatomy

The first scientific work on the structure and function of the pulp was written by the Swiss Walter Hess in 1917. Interestingly, two years earlier, the Austrian Moral described the fact that in 60% of cases, the first upper molars have four canals. This became a postulate only in recent years, when it became possible to widely use the microscope in endodontics. Langeland examined the pulp under a scanning electron microscope and in 1959 published his work on the structure of the pulp. Seltzer and Bender in 1965 published the book "Tooth Pulp", which summarized knowledge about the biology, physiology and pathophysiology of the pulp. The authors believed that endodontics is inextricably linked with periodontology, since these two sections describe one tissue complex - periodontium. The book was reprinted and supplemented several times and became a basic textbook for students. After the relationship between diseases of the periodontium and internal organs has been proven, scientists and practitioners are interested in the question of the dependence of the development and course of pulp and periodontal diseases on the landscape and the pathogenicity of microorganisms vegetating in these tissues, on the one hand, and the reactivity of the periodontium and the body in in general, on the other hand. The correct answer to this question will allow you to prescribe and conduct a rational treatment of the disease in a particular patient.

Diagnostics.

Diagnosis, as you know, includes: taking an anamnesis of the disease and life, with an emphasis on the allergological status and the functional state of internal organs and systems; objective examination of the patient's maxillofacial region for the presence of asymmetry, edema, fistulas; palpation of the lymph nodes, temporomandibular joint. Examination of the oral cavity is aimed at studying the state of oral hygiene, mucous membranes, periodontal tissues, diagnosing inflammation, fistulas. Only after carefully examining the oral cavity, the dentist begins to study the causative tooth (presence of a carious cavity, restorations, test for sensitivity to temperature stimuli, percussion test, x-rays), not forgetting the comparative assessment of adjacent teeth. If after that the diagnosis remains unclear, clinical tests are repeated or an additional examination is carried out (for example, x-rays taken in different projections are taken). Analyzing and summarizing the data of clinical and laboratory studies, we make a diagnosis of the disease and outline a treatment plan.

Endodontic treatment

The goal of endodontic treatment is the long-term preservation of the tooth as a functional unit of the masticatory apparatus, the preservation of the tooth as a functional unit of the masticatory apparatus, the restoration of the health of the periapical tissues and the prevention of autoinfection and sensitization of the body.
According to the recommendations of the European Endodontic Association, Indications for endodontic treatment are:
- irreversible inflammatory processes or pulp necrosis with or without radiological changes in the periodontium;
- doubtful condition of the pulp before the upcoming restoration, prosthetics;
- extensive traumatic opening of the tooth cavity during preparation;
- planned resection of the root apex or hemisection.
Contraindications to endodontic treatment include:
- teeth with poor prognosis;
- teeth with extensive periapical rarefaction;
- destroyed teeth that cannot be restored or used in further prosthetics;
- Lack of interest of the patient in the treatment of the tooth.

Documentation

Complaints, anamnesis, clinical and radiological examination data and, possibly, the results of previous treatment should be recorded in the patient's medical record. The patient needs to outline the treatment plan, explain what problems the dentist may encounter during treatment, for example, with a sclerosed or curved canal, etc. It is also necessary to discuss the financial side. And, most importantly, the patient must give informed consent to endodontic treatment!

Anesthesia

The choice and dosage of the anesthetic depends on the age, weight, duration of the dental intervention and the patient's allergy history. It is important that anesthesia is administered slowly! Even with the introduction of a small amount of anesthetic in the soft tissues of the oral cavity, significant pressure occurs, leading to local pain. And, of course, we should not forget about the aspiration test. The erroneous introduction of an anesthetic into the bloodstream increases the risk of a toxic reaction by several times. The use of devitalizing pastes based on arsenic or paraformaldehyde is not recommended.
The rubber dam system can be applied in three ways. One of them involves the imposition of a clamp along with a latex curtain.
In this case, the curtain is first put on the arc of the clamp, then the clamp is applied to the tooth, after which the latex curtain is put on the vise of the clamp and pulled onto the frame

rabbeddam

The use of a rubber dam in endodontic treatment is a must! Rubber dam provides aseptic working conditions, prevents contamination of the tooth cavity with microorganisms from saliva or exhaled air, protects the patient from aspiration and swallowing of small endodontic instruments. With the help of a rubber dam, time is saved, the burr hole is easily accessible, and the quality of treatment is significantly improved. In the US, for example, if a dentist performs an endodontic treatment without a rubber dam, they may lose their medical license. This disorder is easily identified by x-rays taken during endodontic intervention (presence of clamps).

Trepanation

Endodontic baking begins with access to the cavity of the tooth. Difficulties in root canal instrumentation are a consequence of insufficient trepanation or non-straight access to root canals. When forming a burr hole, you should always remember about the anatomy of the tooth. Indirect access to the root canal leads to bending of the files, impossibility to pass the root canal and, as a result, to possible perforation or breakage of the instrument.
A new series of instruments for manual preparation Senseus with a soft silicone handle from Maylifer / Dentsply (Switzerland)

Determining the length of the root canal

Determining the length of the root canal is the most important step in endodontic treatment. It is this parameter that determines the success of the treatment. Improved electronic apex locators make it possible to determine the length of the canal quite accurately, but an X-ray image taken with an instrument inserted into the canal gives an idea not only of the length of the canal, but also of its curvature or the presence of additional canals. When taking an x-ray, you should always remember that the anatomical apex is located at a distance of 0.5-2 mm from the radiological apex.
A huge step forward was made thanks to the discovery in 1895 by V. Roentgen of X-rays. In 1896, physician Walter Koenig presented the first x-rays of the upper and lower jaws. Nowadays, the use of a digital radiovisiograph in dentistry opens up new prospects: the possibility of computer processing of images, color visualization, and, in the near future, 3D tomography. The first 3D images have already been presented, but so far the processing of such an image can take more than 12 hours. However, this is only a matter of time. For comparison: in 1896, it took more than an hour to develop an X-ray image, and today it takes seconds.

Root canal treatment

The purpose of mechanical root canal preparation is to remove the vital or necrotic pulp, as well as the affected and infected dentin. The root canal must be processed in accordance with its anatomical shape. Only an adequately machined root canal ensures the penetration of antiseptic solutions into the root system and its reliable disinfection.
Even at the end of the 19th century, the Micro-Mega company proposed the Jiromatic system for mechanical treatment of root canals. In the 1960s, chromium-nickel alloy endodontic instruments were first made. At the same time, all instruments were classified according to ISO (International Organization for Standardization) according to length, size, shape, taper. The year 1988 was revolutionary for endodontics, when a nickel-titanium alloy began to be used for the production of endodontic instruments. Possessing an elastic modulus and a memory effect, this alloy allows the instrument to bend with less resistance, pass curved canals without deforming their anatomical shape. With the use of nickel-titanium instruments, root canal treatment has become faster, more efficient, and safer.
Application of calcium hydroxide paste into the root canal.
Sequence of active nickel-titanium instruments ProTapers (Millifer/Dentsply, Switzerland)

Root canal disinfection

According to Pineiro's work, Enterococcus, Streptococcus, and Actinomyces are the most common in an infected root canal. Among them, 57.4% are facultative anaerobes and 83.3% are gram-positive bacteria. The antiseptic solution used for washing the root canal should not only destroy microorganisms, but also dissolve the remaining pulp tissue, affected dentin, and endotoxins. Only a combination of several antiseptic solutions (for example, sodium hypochlorite and ELTA) can achieve the desired results. Now scientists are developing a technology for electromagnetic activation of chemical solutions used to disinfect canals in order to expand the spectrum of their antibacterial action.

Medicines

If it is impossible to seal the root canal in one visit, especially in case of infected and necrotic processes, it is necessary to leave a medication in the canal designed to destroy the remaining microorganisms, endotoxins, and disinfect the infected dentin. In the dental market, the range of drugs used for root canal disinfection is quite wide: formocresol, cresatin, phenol, antibiotics, steroids, calcium-based preparations. Calcium hydroxide (Ca(OH)2) has become especially popular for endodontic treatment. Due to its high alkaline reaction (pH 12.5-12.8), calcium hydroxide not only has antibacterial properties, but is also able to dissolve infected tissues and stimulate bone tissue repair in the periapical region.

Root canal filling

Ideas about the three-dimensionality of the root system, presented even in the 70s of the XX century, have again become popular. The root canal should be viewed as a complex three-dimensional system consisting of a main canal and many microchannels and branches. The filling material must fill the entire root system, tightly adhering to the walls of the canal, preventing the penetration of microorganisms or liquids (blood, saliva). The quality of the canal filling should always be checked by x-ray.
Unfortunately, there is still no ideal filling material. But the selected material for filling the root canal system should:
- be non-toxic;
- be spatially stable (have no shrinkage);
- fit tightly to the walls of the root canal;
- do not dissolve (there are exceptions in pediatric dentistry);
- be radiopaque;
- do not stain the tooth;
- do not support the growth of microorganisms;
- it is easy to be removed from the channel if necessary.
Gutta-percha, due to its non-toxicity, plasticity and easy removal from the root canal, if necessary, has been used as a filler for several decades. The use of various canal filling modifications (eg vertical technique) has made gutta-percha a favorite in endodontics. Qualitatively new materials have already been created for root canal filling using adhesive technology, excluding the penetration of microorganisms and liquids between the root canal wall and the sealer (EndoRES, Ultradent). The first clinical studies have shown good results, but experience with them is still insufficient.
According to the recommendations of the European Association of Endodontics, the success of endodontic treatment should be monitored radiologically and clinically for 4 years. Recommended time intervals for monitoring after treatment are 6 months, 1, 2 and 4 years.

The Future of ENDODONTICS

Many books and scientific treatises have been written about endodontics. The history of endodontics is a long journey from empirical knowledge to the scientific approach of the 20th century. The computer XXI century introduced technical innovations into endodontics, which have already become a necessity today: the use of a digital radiovisiograph, an operating microscope, and an apex locator. All these new achievements prove again and again that not only endodontics, but dentistry as a whole is closely related to immunology, biology, cytology, and engineering.
Today Philadelphia (USA) is considered the Mecca of endodontics. Thanks to the scientific work and innovations introduced by the head of the Department of Endodontics, Professor Kim, endodontics has become an independent division in dentistry. Kim expanded the scope of endodontics, closely connected them with periodontics and surgery, creating a completely new direction in dentistry - microsurgery. Since 1999, students studying at the department of Professor Kim have been using an operating microscope for endodontic treatment. Kim's influence on the development of endodontics is so great that, according to experts, in order to develop and improve all his ideas, even this century will not be enough.
Of course, a lot of attention in endodontics will be given to the patient, especially microbiology and the fight against resistant microorganisms, as well as strengthening the patient's immune system. Knowledge about the stem cell growth factor, the structure of the new tissue, and with them the desired regeneration of periodontal tissues, and possibly even the pulp, will be expanded. Pain will no longer deter patients from dental treatment, and doctors will understand the nature of its occurrence.

Modern endodontic instruments

European Dental Academy, 2012

UDC 616.314.17 - 008.1 LBC 56.6

ISBN 5-88301-081-4

Published by decision of the presidium

European Dental Academy

and Academic Council of the Kuban Scientific School of Dentistry

I.V. Malanin - professor, academician of the Russian Academy of Natural Sciences, doctor of medical sciences, honored worker of science and education.

Reviewers:

V.F. Mikhalchenko - professor, academician of the EAC, doctor of medical sciences, head of the department of the Volgograd State Medical University.

Mark Reifman is Professor at the European Academy of Dentistry, Rishon LeZion, Israel.

The book is a work of a specialist in the field of endodontics. The author of this textbook is a practicing doctor who deals with endodontics on a daily basis, so he not only writes, but also perfectly knows the problem that this book is devoted to.

AT The book describes the most popular endodontic instruments used today in the world endodontic practice. It also describes the rules and features of working with modern instruments that every practitioner involved in endodontic treatment needs to know.

AT Due to the fact that this publication is intended primarily for students and young professionals, at the end is added a chapter that is not usual for academic publications: “The path to success in dental practice”, in which the author gives answers to the questions most relevant for a young doctor. What is the difference between internship, residency, graduate school, and does everyone need it? Where is it better to go to work after graduation: to a private, municipal clinic, to the dental department, or to strive for your own business? Which of dentists best to study? How to get to study with a good doctor and how much can this training cost? How to choose a supervisor for a PhD thesis, and is it needed at all? How can a young doctor make more money and be successful in his dental practice? Young specialists will find answers to all these questions in the pages of this book.

Gratitude

I I am very grateful to my first teacher - in dentistry, Sergey Isaakovich Drawn, who, at one time, made a real specialist out of a young doctor - a dentist. He taught me not only manual skills and clinical thinking, but also gave me many good life lessons.

I I am grateful to Kravchenko Arkady Ivanovich, he not only inspired me to write this and many other books, but also made me a Person. I owe a lot of my life to him. Thank you teacher!!!

I I am very grateful to my wife Marina for her help and moral support in preparing this publication. Also a professor of psychology, she helped me a lot in writing the last chapter of this book.

Thanks to the reviewers of this publication. Mikhalchenko Valery Fedorovich - he made a huge contribution to the development of therapeutic dentistry not only in Russia but also abroad. At one time, this great scientist and talented doctor helped me a lot in becoming a scientist.

I thank my friend and teacher Mark Raifman for reviewing this edition. This world-famous scientist is better known to Russian endodontists as the inventor of the apex locator. It is a great honor for the Russian edition - the attention of a specialist of this level.

Teachers learn themselves as long as they have students. And based on my own experience, I can say that this is exactly the case. I would like to thank all my students.

In modern dentistry, a paradoxical situation sometimes arises when new, objectively more effective tools in the conditions of their mass use bring worse results compared to traditional ones, but they have been well studied for a long time. This is due to the fact that in modern conditions the doctor is subject to an ever-increasing information and technogenic load, which he is not always able to withstand. Every year, new endodontic instruments are offered, many of which become obsolete before they can be mastered in wide clinical practice. This problem is typical for all medicine in general. In dentistry, where progress can be comparable in pace, perhaps, with progress in the field of computer technology, it is most acute. Students and young doctors suffer especially, for whom, after studying voluminous textbooks in all sections of the specialty, with a lack of their own clinical experience, sometimes chaos reigns in their heads.

I was prompted to write this book by the fact that, unfortunately, many dentists are not familiar with new endodontic instruments and the prospects that open through them, since universities did not teach their use, and the financial capabilities of young professionals do not allow obtaining relevant information.

For successful dental practice today, it is necessary to revise some of the "classical" approaches. Only new approaches and new techniques can lead to success. Without books, manuals, it is impossible to learn dentistry and maintain your qualifications. From books, a modern dentist receives information that helps to avoid costly mistakes.

Based on the foregoing, I made an attempt to describe some of the most popular endodontic instruments currently used in world endodontic practice, and considered it possible not to dwell on the description of instruments and materials that are sufficiently fully covered in the widely available domestic literature. Since such instruments as rasps, drills , pulp extractors, applicators, are historically the oldest types of endodontic instruments and have been used

back in the 19th century. In modern endodontic practice, they are of limited use.

I also allowed myself to deviate from the generally accepted terminology for describing some materials and tools adopted in Russia. This is due to the fact that at the global level, back in 1973, the International Federation of Dentists (FDI) and the International Organization for Standardization (ISO) assigned responsibility for the development of standards and standardization of dental materials and instruments to the American National Standards Institute.

American National Standards Institute: Meeting of the ISO CommitteeTC-106 (Dentistry), Chicago, 1974, American Dental Association. FDI and ISO continue to develop international standards for endodontic instruments today and efforts are coordinated at many levels. In Europe, the development of standards and standardization of dental materials and instruments is coordinated by the European DentalAcademy.

A few years ago, students performing routine endodontic manipulations did not think about quality standards. Recently, a graduate of a dental school is better at almost all stages of conventional endodontic treatment. As endodontic treatment without complications becomes an integral part of dental care, its "mystery" disappears.

The methods and principles of apical surgery have been completely revised with the introduction of the surgical microscope, ultrasonic treatment and micro-instruments, with which it has become possible to work more precisely and more gently. The operating microscope occupies an important place in endodontics. The use of an operating microscope in endodontics adds confidence, accuracy, quality and efficiency of treatment to the doctor. With its help, it is easier to find an atypically located canal, you can avoid many complications, such as instrument separation, it is easier to remove pins with new instruments, and also to monitor the treatment process.

Today, the success of endodontic treatment is a reality. Many of our happy patients, having got rid of pain, will agree with this. However, incorrectly performed techniques cannot be considered successful only on the basis of the absence of obvious symptoms in the patient.

We must not deceive ourselves. Failures happen, and will occur, despite the great efforts of doctors and the constant improvement of methods. Our goals may be noble and lofty, but we cannot always achieve them, and often this is due to the fact that we are dealing with a human body that does not always behave as it is written in books.

It should be noted that if maxillofacial surgery in Russia in the applied and scientific fields was close in level to the achievements of America and Europe, then orthopedists and dentists in our country could not boast of this. The openness of our society in the last 20 years, integration with foreign technologies, the spread of modern equipment and tools in the market of our country, as well as the growth of alternative branches

and offices were not slow to have a positive impact on the level of dental treatment. It is no secret to anyone that it is private practitioners who drive progress in Russian dentistry. And today, the result of treatment no longer depends on the equipment and surroundings of the dental clinic, but on knowledge and skills. In this regard, the publication brought to your attention is intended to achieve this goal.

AT Due to the fact that this publication was intended primarily for students and young professionals, I added at the end a slightly unusual chapter for academic publications: "The path to success in the practice of dentistry."

For almost 20 years, I divided my time between science, teaching

and private dental practice. In this regard, in this chapter I have answered the most frequently asked questions of young professionals who have graduated from high school. Do I need a residency, or is an internship enough? Who better to learn from, and how to get trained by a good specialist? Which way to go to become a sought-after and well-earning specialist? In this chapter, young professionals will find answers to all these questions.

I am sure that while reading this book in your client

long-awaited changes will begin to take place in human practice.

) - dentist therapist, orthodontist. Engaged in the diagnosis and treatment of anomalies in the development of teeth, malocclusion. Also installs braces and plates.

Endodontics and methods of endodontic treatment is one of the sections of dentistry that deals with the treatment of dental canals, analyzing and studying:

• anatomical features and functional structure of the endodont;
• pathological processes and changes arising in it;
• technique and methodology of therapeutic effects and various manipulations in the dental cavity and its canals;
• the possibility of eliminating inflammatory processes in the apical periodontium and inside the cavity of the tooth.

Using various endodontic methods of treating and filling infected teeth, it is possible to protect them from further severe destruction, prevent serious complications that can lead to bone and soft tissue disease and tooth loss. In other words, we can say that endodontics is odontosurgical manipulations carried out in order to save the tooth.

Before proceeding with treatment, a thorough collection of the patient's history and diagnosis of dental problems that have arisen are carried out. In doing so, perform:

• visual inspection - to determine the shape, color and position of the tooth. Check the condition of hard tissues of dentin (the presence of fillings, caries, inlays), its stability, the ratio of its alveolar and outside the alveolar part;
• collecting a patient's medical history - complaints, a history of the onset of a dental disease, the presence of aggravating diseases and allergies;
• clinical examination of the patient - assessment of the conditions of the oral cavity and its mucosa, dentition and periodontium, examination of the masticatory muscles and temporomandibular joints;
• paraclinical examination - X-ray examination with obtaining a picture, electroodontometry using sensors, laboratory and instrumental methods.

The sequence of endodontic treatment of teeth

Modern endodontics consists of the following steps:

Step 1. Opening (preparation) of the tooth

The procedure for abdominal opening of the tooth begins with the removal of the affected dental vault and its crown part; it is unacceptable to start the preparation from the side of its cutting part. The boundary of the area of ​​the burr hole should be such that free access of dental instruments to the pulp zone of the coronal part and to the root canals is provided.

In the case of a correct opening of the dental cavity, there should not be: overhanging edges of the arches of the open cavity, thin walls (the thickness should not be> 0.5-0.7 mm) and the bottom. The procedure is performed with the help of turbine machines equipped with: endodontic excavators, endoburs, surgical burs, burs and Ni-Ti files to open the orifices.

Step 2. Search and sounding of canal mouths

First, they try to determine the location of the roots of the tooth with their canal orifices using X-ray examination. Further probing is carried out using two-ended, straight probes with different angles of inclination.

When access to orifices is difficult due to overhanging dentin or denticles present, it is advisable to remove the interfering dentin layer with a Muller or rosette bur.

Step 3. Study of the length of the tooth and its root canals

One of the main stages of dental canal therapy. Proper implementation of it, makes it possible to carry out all further necessary manipulations without hindrance and quality and eliminates the possibility of complications. At the moment, three variations are used to determine the working length of the root canal:

• mathematical or tabular calculation method. According to the tables, you can determine the range of fluctuations (from the minimum possible to the maximum) of the length of the teeth. The method is not accurate enough, due to possible deviations in the average length of the teeth (error about ± 10-15%). The tools for measuring the working length are K-Reamer and K-File, Flexicut-File is used in the curved canal;
• electrometric or ultrasonic methods. Research is carried out with special apex locators. These devices are self-regulating and do not require any additional setup or calibration. The principle of their operation is based on the difference in electrical potentials between the soft tissues of the tooth (periodontium) and its hard tissues (dentin), which allows you to accurately determine the location of the apical constriction.
  The apex locator itself consists of two electrodes and a dashboard. One of the electrodes is fixed on the lip, the second (file) is tightly located in the dental canal and smoothly, without shocks, moves along it. As soon as it reaches the lower point of the apical constriction, the circuit closes, an audible signal sounds and the display shows the value of the speed of the electrical impulse, which makes it possible to automatically calculate the depth of the canal in the future.
  Modern electrometric apex locators operate in the presence of electrolyte, moisture, hydrogen peroxide, blood and do not distort its readings. When working with milk teeth or teeth with unformed roots, the device is not used;
• X-ray method is the most reliable and frequently used, which allows you to clearly visualize the degree of canal patency, establish its length and direction, determine the presence of curvature, perforations, and find out the condition of the periodontium. For chewing teeth - the working length is considered from the buccal dentition, for the anterior - from the cutting tooth edge, while it should be shorter by 0.5-1.5 mm distance to the highest point of the crown part of the tooth.

Step 4. Expansion of the mouths

To facilitate the introduction of the expansion tool, for the purpose of further medical and mechanical manipulations in the root canal, an operation is performed to expand its upper third and mouth. During the procedure, a wide, straight, funnel-shaped, cone-shaped mouth is processed and formed. Dilation can be done manually or with a polishing endodontic handpiece.

Step 5. Removal of unhealthy pulp (depulpation)

The main therapeutic indications for the use of the procedure:

• acute inflammation of the pulp, as a result of serious pathogenic lesions and toxic decomposition, of its neurovascular bundle;
• as a preliminary operation before installing crowns, clasp and bridge prostheses;
• mechanical trauma with a chipped tooth and exposed pulp;
• severe forms of periodontal disease, periodontitis;
• before ;
• restoration of teeth;
• unsuccessful dental intervention;
• congenital anomalous arrangement of some teeth in rows;
• as a preparatory procedure for the installation of crowns, semi-crowns.

Vital method of pulpotomy

It is used for early pulpitis, when the lesions have affected a small area of ​​the pulp and it can be completely removed in one visit to the dentist. The depulpation operation is started after receiving an x-ray of the affected area and the introduction of an anesthetic. Next, the tooth is reamed, followed by the removal of dentin residues and carious tooth enamel from the damaged cavity.

In order to penetrate to the surfaces with inflamed and oppressed pulp, a part of the tooth surface is cut off, the canals are searched for and expanded, then, with a pulp extractor, the inflamed, infected and softened nerve is removed from the canals and the pulpal dental chamber. A medicine is placed in the resulting cavity, which has a beneficial effect on the tissues of the tooth, promotes their healing and regeneration.

A temporary filling is installed, which is then removed by the dentist after 3-4 days, and in its place, after the treatment of the tooth cavity with an anesthetic, a permanent filling is applied.

Devital pulpotomy

It is used in the treatment of advanced cases of pulpitis. This technique provides for the implementation of complete depulpation in 2 dental sessions. The step by step process looks like this:

• x-ray examination of a diseased tooth;
• local anesthesia;
• opening of an infected, affected cavity;
• cleaning the tooth cavity from dentin residues, washing with a potent antiseptic;
• immersion in the tooth cavity of a medicinal paste for the death of the pulp and the outflow (drainage) of pathogenic contents;
• an open tooth cavity with pulp and paste is covered with a temporary filling;
• after 3-4 days, the temporary filling is removed and a thorough mechanical cleaning of the necrotic pulp mass is carried out, the root canals are cleaned;
• treatment with a special antiseptic composition for the complete mummification of the pulp, the imposition of a temporary filling;
• in the absence of pain in the treated tooth after 2-3 days, it is covered with a permanent filling.

In some cases, surgical depulpation leads to complications. Endodontists note such problems as: the appearance of cysts at the top of the root, the development of purulent periostitis of the periosteum (flux), they can diagnose a fistula or a granuloma that is formed.

These diseases can occur as a result of poor-quality depulpation and the introduction of pathogens during surgery. To avoid possible inflammation and the need to re-visit the doctor, a permanent filling is installed only after X-ray control (a picture is taken) of the filling of the treated root canals.

Step 6. Permanent filling (obturation) of the dental canals

Setting a permanent filling, sealing root canals is an important, final part of endodontic dental treatment. Filling allows:

• restore the functionality of the periodontium;
• prevent and eliminate the inflammatory process;
• prevent the appearance of inflammation in the maxillofacial region;
• prevent the penetration of pathogenic microorganisms into the periapical tissues.

Ways to fill canals with filling material

1. Side (lateral) condensation method. The technique is quite effective with a stable result, not requiring large expenditures. It uses several gutta-percha pins with a minimum amount of sealer (hardening paste), which makes it possible to achieve a complete hermetic filling of the root canal and apical opening;
2. Sealing with the Thermofil system. The main advantage is that it allows obturation of both the main canals and branching lateral tubules;
3. Single pin technique. At the same time, a hardening filling paste and a pin are introduced into the root canal for its uniform distribution and sealing. This method allows you to reliably seal narrow and rather curved canals;
4. Technology using liquid injectable heated gutta-percha. Gutta-percha is fed into the root canal in blocks on a carrier placed in a heating device, where it is brought to 200 ° C and fills the canal. The method of hot vertical condensation allows you to install a seal in curved canals, in canals with a bent top of the root or its bifurcation.

Basic dental filling materials

• fillers (solid materials). These include silver and titanium pins, gutta-percha;
• sealers or cements to fill the space between the walls of the tooth and the post. They may contain antiseptic, analgesic, anti-inflammatory additives in their composition.

Filling tools: pluggers, guta condensers, heating plugger. root needles, manual or machine canal fillers, manual or finger plugger, spreader, syringes.

Sources used:

• Re-endodontic treatment. Conservative and surgical methods / John S. Rhodes. — M.: MEDpress-inform, 2009.
• Modern approaches to endodontic treatment of teeth. Textbook / O.L. Pikhur, D.A. Kuzmina, A.V. Zimbalistov. — M.: SpecLit, 2013.