The Road to the Perfect Endodontic Treatment
Worldwide, most general dentists do not list re-treatment of failed dental treatment as a routine treatment item.
There are many reasons, the three most common are:
Lack of experience,
Untrained,
Requires special equipment.
In this article, we will introduce the principles and techniques of retreatment, mastering these principles and techniques, many dentists may consider adding some specific and specific types of endodontic retreatment items to the clinic’s routine treatment items. And, if dental pulp treatment failure does occur, we can also refer to the special methods we discussed to evaluate the cause of dental pulp treatment failure.
The goal of endodontic treatment is to achieve three-dimensional cleaning, shaping and sealing of the root canal system. This system includes the entire space from the root canal to the apical foraminal stenosis (Figure 1). Endodontic treatment should mimic the effect of pulp extraction. Extraction is the healing of affected teeth by removing infected pulp. To the greatest extent possible in endodontics, removing all infected pulp and then closing the coronal pulp is the key to ensuring tooth healing.
In contrast, there are three very clear reasons for the failure of endodontic treatment: uncleaned and filled areas in the root canal system (root canals containing necrotic pulp tissue are missing), and microleakage in the crown ( Saliva and the bacteria it carries contaminate the root canal), and vertical fracture of the root canal (Figure 2
4). When endodontic treatment fails, a solution can only be found if the cause of the failure has been identified.
This solution may be extraction, retreatment by a regular dentist, or referral to a specialist for retreatment or apex surgery and / or surgical correction. After completing the treatment, it is necessary to observe the treatment effect over a period of time. The results of endodontic treatment are divided into:
Successful cure,
Unsuccessful treatment,
And / or the treatment effect is suspicious.
Characterization of successful endodontic treatment:
- Judging whether the endodontic treatment is successful requires a return visit / observation period of at least two years, which may be a bit arbitrary. Usually, the review is performed after 6 months and after 2 years. During the re-examination, the dentist needs to detain, palpate, inspect the activity, and explore the teeth. The results of these inspections should be within the normal range. In addition, the teeth must restore integrity and function. The criteria for absolute treatment success should be that the patient is asymptomatic.
- It should be noted that not only must the crown be repaired, such as a protective crown, but the teeth must be completely closed to prevent crown leakage.
In other words, for a temporarily filled tooth with a cotton ball in the medullary cavity, a permanent crown cannot be placed. According to the author’s clinical experience, many of the teeth that need to be retreated are crowns with good airtightness, but wet and ambiguous cotton balls are found in the root canal, and the root canal is filled with temporary fillings. (Figure 5.6).
3． Ideally, the dentist takes x-rays from multiple angles and observes that the periodontal attachment has not been damaged from the radiological perspective (and / or there is no damage caused by the endodontic cause. These damages will appear in any part of the periodontal attachment ) And healed completely.
4． The health of the periodontal tissue was not compromised in any way during endodontic treatment.
Characterization of difficult treatment (either alone or in conjunction with other signs):
- Patients experience any type of clinical pain from dull pain (especially when chewing) to spontaneous pain. No matter how mild the symptoms are, in terms of clinical manifestations, the most common is that patients do not have to chew their teeth. In other words, if the patient’s teeth are not capable of chewing, at least the treatment effect is not clear, and it will take longer to evaluate the long-term effect of the treatment.
- At the same time as the above symptoms, there are important deficiencies in the biological goals of root canal therapy. Often, these defects are manifested as significant uncleaned and filled sites in the root canal. In addition, imperfect treatment can be manifested as one or more operating errors (perforation in any part of the root canal, oversized apex holes, overhangs, dentin debris blocking the root tip, broken roots, and enlarged root canal rupture There are many other potential problems) (Figure 7).
3． The root canal treatment may be perfect, but the coronary pulp is not closed. The operation of root canal therapy is very complicated, but its treatment requires the restoration of the crown or the simple operation of wearing a crown to protect it. This is quite ironic. Coronal closure is very important, which is closely related to the long-term maintenance of successful endodontic treatment. No matter how successful the previous endodontic treatment is, as long as the gum tip is exposed to saliva, bacteria can spread along the gum tip to the root tip after a few days or weeks, causing infection around the root tip.
4． Chronic sinus (fistula) appears.
- Slight or repeated swelling.
- Previously healthy periodontal problems.
- The periodontal ligament, which was still healthy before treatment, was damaged, or after treatment, the periodontal ligament was more severely damaged or did not improve.
What should I do if there are no symptoms in the tooth, but there is a defect in the quality of the blood?
This question includes several minor issues that may affect the dentist’s decision. If there are obvious defects in the endodontic treatment (for example, the filling of the root canal is under 5mm) has existed for a long time (several years), the crown part is repaired well, and the X-ray picture does not exceed The normal range of abnormalities, the patient has no symptoms, and no operating errors occurred during treatment. The root canal can be temporarily moved and continued observation. However, if there is a major operating error, or a leak in the crown, or a pathological change in the apex on the radiograph, such a root canal should be retreated. Such teeth need to be re-treated especially if the crown part of the tooth needs to be restored, or if the tooth has significant strategic value, and / or the patient has clinical symptoms.
Another similar situation is that, from the perspective of the x-ray film, the transmission area of the apical portion is reduced, indicating that healing is taking place, but this transmission area has not completely disappeared, and the patient has no clinical symptoms. Do such teeth need to be re-treated? The specific situation should be analyzed specifically. If the dental pulp is successfully treated and the crown is closed well, the teeth can be considered normal. If there are some defects in crown closure or endodontic treatment, then this tooth is best re-treated.
If an endodontic treatment is confirmed to be a failure, the most important thing for a practicing dentist is to make several decisions that will correctly guide future clinical operations. These decisions can be summarized with a few questions that make it clear that the dentist can take the correct action (referral, treatment, or extraction).
- Can and should this tooth be repaired?
- Does this tooth have preservation value and periodontal health? If the tooth cannot be repaired, and periodontal treatment cannot restore health, extraction may be the best choice.
- If the prognosis of re-treatment may not be optimistic or even hopeless, is extraction a better option? At the very least, patients should be made aware of all options (re-treatment, fixed bridge, implant treatment, or no repair) ) And each of these options has a chance of success (Figure 8).
- Is the patient willing to spend time and money on re-treatment and restoration of the crown? Does it require permanent restoration?
- Can the operating mistakes made up be compensated? Can the experts correct these mistakes? Can you find an expert? Can the general dentist in the clinic deal with these mistakes?
It is very important not to try to restore the function and shape of the teeth when the first retreatment fails or the endodontic treatment is not completed satisfactorily. Taking into account various factors, it can be very bad to start making a new bridge or crown before a tooth is ready for a new restoration. Another situation is that the dental condition is better from all aspects, only new crowns and bridges need to be restored, but this situation is rare.
In summary, dentists need to carefully evaluate current treatments (through the methods discussed in this article) and assess the likelihood of successful treatment with this regimen before determining a retreatment regimen for a certain type of clinical condition (these treatments are within the scope of work in a general dental clinic). Sex, even more careful when the patient does not have any symptoms.
When do you need expert help?
Circumstances that require expert help for retreatment may include the removal of various metal fragments (including silver cones, broken root canal enlargement needles, lentul0 helix, Peez0 drill, Gates Glidden drill, K file, drill, stainless steel rotary K File head, ultrasound head with possible broken tip, hedstrom endodontic needle), treatment of various types of perforations, removal of overhangs and root canal obstructions (obstructions other than metal fragments, such as Thermafil carrier, Thermafil, Dentsply Tulsa Dental , Tulsa, OK, United States).
In general, if the previous endodontic surgery failed and needs to be corrected, or if teeth that require surgical intervention are encountered, it is best to refer to an endodontic specialist for treatment. Of course, there are some exceptions. The more complicated the problems that arise, the greater the need for expert diagnosis and treatment. In addition, there is a case where it is difficult to quantify the evaluation, that is, at any time, as long as an ordinary dentist feels that he has enough energy and lack of ability for a clinical case, or if he is referred to an expert for treatment, the patient can get better services, then For the benefit of patients and dentists, dentists can refer patients to specialists for treatment.
One type of endodontic treatment failure cases is suitable for re-treatment by general practitioners. This situation is that the root canals of the teeth have not been sufficiently cleaned and filled, and no obvious treatment errors have occurred. Generally speaking, if there are only small defects in the existing treatment or dental pulp treatment failure due to crown microleakage, there are no obvious disadvantages. At this time, the re-treatment can be completed by a general practitioner.
For such teeth, once the previously closed material is removed and the root canal is unobstructed, the next treatment required is the same as the first endodontic treatment. If the dentist operates correctly, has the proper equipment, and is properly trained, such a tooth can be completely retreated in an ordinary dental office (Figure 9). The detailed steps for retreatment of this tooth are as follows.
Principles and methods of new treatment of dental coins without treatment errors
Very careful inspection is required before operation. Once you open your teeth, you may find unexpected mistakes in the previous operation, or you may find errors that are not obvious on the radiograph. For example, you may find that small fragments of the 6 1 0K file break at any part of the root canal.
Can’t see in the photo. In addition, caries under the crown are not easy to find on x-rays (others are not easy to find on x-rays also include reabsorption, pegs, small posts, etc.). In the process of entering the root canal, various reasons for the failure of the previous treatment can often be found. If this happens, the dentist may need to change the treatment plan made before the root canal is opened.
It is worth mentioning that the special materials required for retreatment after root canal treatment failure are also very important, and their importance is second only to the principle of recanalization of root canals. In fact, as long as the main principles of retreatment are followed, the dentist may successfully complete the endodontic treatment (either the first root canal treatment or the retreatment) regardless of the existing instruments at hand. That is, from my personal experience, certain systems (root canal enlargement needle systems, closure materials and techniques, irrigation systems, ultrasound instruments and ultrasound heads, heat sources, dental gum tips, etc.) are more useful than others It is more convenient and the treatment efficiency is higher.
The clinic insists on the principled introduction of these latest technologies and materials to fully optimize the quality of services. The following will explain in detail
New treatment efficiency equipment. The key issue to understand is that these devices are not sufficient to complete the retreatment of the clinical cases described below. Even the most common devices can successfully correct many failed endodontic treatment cases.
Finally, it is important to emphasize that not only does the dentist take the time to re-treat, but also does not rush when performing various types of endodontic treatment. Re-treatment of the dental pulp particularly requires unconditional concentration, and it is not advisable to treat multiple patients at the same time, even the most talented
The dentist also needs to concentrate on re-treatment, slowly “decomposing” the failure of the previous treatment, and “rebuilding” the results of the endodontic treatment. Retreatment should never be done casually. To summarize, the general principles and techniques of perfect endodontic retreatment include:
Correctly assess the patient’s dental history and systemic disease history, and assess the patient’s main pulp symptoms in detail. Examination of detailed endodontic symptoms includes endodontic activity testing, withholding, palpation, examination of activity, probing the teeth from various angles (and, if possible, jaw teeth), taking x-ray pictures from multiple angles to assess suspicious teeth, The dentist should use these tests to reproduce the patient’s symptoms in order to confirm the diagnosis.
For teeth that have failed symptomatic root canal treatment, tooth pain is usually more pronounced during compression. The greater the intensity of the pressure, the higher the frequency, and the longer the duration, the more severe the tooth pain. This pain is associated with chewing and may also be swollen. For teeth that have failed asymptomatic endodontic treatment, the teeth may show chronic sinus tracts (fistulas) or slight or repeated swelling without pain.
Before diagnosis, the dentist needs to reproduce the patient’s main symptoms. One case is the presence of hot and cold irritation, which is consistent with the apparent failure of root canal therapy. If the patient has hot and cold irritation, pay special attention to asking whether the patient is more sensitive to temperature or more sensitive to pressure. If the patient’s pain is more sensitive to temperature, the affected tooth can usually be located by giving appropriate cold or heat stimulation. Obvious cases of failed root canal therapy may require retreatment, but it is also possible (in this clinical situation) that the dentist caused cold and hot irritation in the recurring tooth pain check before diagnosis.
The dentist should fully inform the patient about the nature of the treatment, tell them about the options available, explain the risks of the treatment, and answer the patient’s questions. It is actually getting the patient’s consent. Patients should be told that the chance of successful retreatment is slightly less than the first treatment. If the treatment fails, it may be necessary to extract teeth or perform surgical treatment. It is important for patients to understand these. The second re-treatment (the third treatment of the root canal) is unlikely to successfully improve the prognosis of the tooth, especially when the first treatment is performed according to high standards but the treatment fails Will be smaller.
Giving patients proper anesthesia is the foundation of quality service. It is difficult to make patients feel comfortable without anesthesia.
The main point of the operation is to use a rubber barrier, go straight into the root canal, give proper irrigation, reproduce and maintain the openness of the root canal and apex. In the retreatment, the author’s experience is often that the previous root canal opening has not been enlarged enough to enter the root canal system in a straight line. Root canal expansion is not allowed
