Root canal therapy atlas shows, too precious!

1. Pith opening: whether the cavity is prepared in accordance with the requirements, whether the top of the pulp chamber is just exposed, and the structure of the cavity wall and bottom is not damaged...

Fig. 1. The split drill was drilled near the pulp. 2. The ball drill penetrated the pulp. 3. The small file was used to probe the root canal orifice

Fig. 4: uncovering the top of pulp with ball drill 5. Trimming the cavity 6. Opening the pulp

2. Decarburization: whether to completely remove the rotten matter from the cavity before root canal preparation, so as to avoid the crown contamination into the root canal during root canal preparation;
3. Straight channel of root canal orifice: especially for curved root canal! Whether to pay attention to this link before root canal preparation, even if the root canal orifice is found, the file can enter the root canal smoothly, but whether the linear channel of the root canal orifice is established is also an important basis to measure the doctor's operation skills. There are many methods: we can use cheap "GG" drill when operating manual instruments, and SX file when preparing ProTaper.

1. Before crown treatment of curved root canal; 2. Prepare with GG drill or SX file; 3. Linear channel formed after treatment

My case 1_____ The filling effect of straight channel in crown treatment

My case 2_____ Filling effect of mandibular 7 "C" type root canal
4. To dredge the middle and lower segments of root canal: small file 08 and 10 K file should be used for exploration. The technique is to rub back and forth 30 degrees in order to establish the preparation channel of the middle and lower segments of root canal, and then use No. 15 K file to dredge, so as to facilitate the entry of large stainless steel instruments or nickel titanium instruments.
5. Determine the working length: when No. 15 K file enters, it is best to cooperate with the root measuring instrument; X-ray should be taken before, during and after operation.
6. Method of flushing: it should be done before and after every file change, but whether it is effective is often uncertain, because the effect of flushing is related to many factors - small needle (if there is no special needle, you can use a small needle for skin test), "Double irrigation method (self named)" - that is, after each irrigation, a small file (such as No. 10 or No. 15) is used to enter the lower part of the root canal and stir it to make the debris float out of the middle and upper part of the root canal with the irrigation fluid, and then the secondary irrigation is carried out, so that the debris in the root canal can be completely removed! Do not remove the irrigating fluid from the root canal after the first irrigation. Its existence plays a very important role!
7. The establishment of root filling file: do not destroy the junction of the apical dentin and cementum, which is of great significance for the later root filling and the choice of the main apex, and the premise is that each preparation should clearly grasp the working length!
8. Stainless steel files and nickel titanium files are the best choice for curved root canals: stainless steel instruments are used to prepare the middle and lower segments of curved root canals, and nickel titanium instruments are used to prepare the middle and upper segments of curved root canals!
9. "Crown root orientation" preparation is a desirable method, but sometimes it needs to be combined with "step back method".
10. Familiar with the performance of the instrument and the clinical key points of various operation methods
There are some problems in the step back method. A. the contact area between the root canal file and the root canal wall is large; Easy to get stuck; The instrument is easy to break; The debris was easily pushed to the apical region; The file tip is not easy to control.); B. Root canal formation is limited (apical irrigation is difficult; Debris removal is difficult; Debris is easy to push out of the apical foramen and cause apical symptoms.) C. The file needs to be changed frequently; The clinical operation time is long.) Therefore, many dentists do not use this method, instead they use nickel titanium instruments for crown root preparation "crown down". But stainless steel instruments (such as K-files) still have their uses - small K-files can be used to find and dredge root canals; It is used to determine the working length; Used for apical preparation; Curved root canal with nickel titanium instruments for preparation is safe!
The advantage of crown down preparation (such as ProTaper) is that it has strong cutting ability, reduces the operation times of the instrument, and also reduces the operation time; The root canal preparation with large taper is convenient for root canal filling; It can effectively remove debris and prevent debris from pushing out of apical foramen; It is easy to remove the crown barrier and obtain a straight passage into the root canal. The procedure of the operation is to investigate the root canal, expand the crown in advance, and determine the working length; Then the middle part of the root canal was prepared; Finally, the apical zone was prepared.
Finally, let's play an evaluation of the quality of root canal treatment - the following picture is a case of Professor Peng bin of Wuhan University. Careful observation can pick out some problems, but there are reasons for the problems! What's your eyesight - what's the problem? There is no doubt about the professional level of the professor. What is the possible reason for this?

The advantage of crown down preparation (such as ProTaper) is that it has strong cutting ability, reduces the operation times of the instrument, and also reduces the operation time; The root canal preparation with large taper is convenient for root canal filling; It can effectively remove debris and prevent debris from pushing out of apical foramen; It is easy to remove the crown barrier and obtain a straight passage into the root canal. The procedure of the operation is to investigate the root canal, expand the crown in advance, and determine the working length; Then the middle part of the root canal was prepared; Finally, the apical zone was prepared.

Finally, let's play an evaluation of the quality of root canal treatment - the following picture is a case of Professor Peng bin of Wuhan University. Careful observation can pick out some problems, but there are reasons for the problems! What's your eyesight - what's the problem? There is no doubt about the professional level of the professor. What is the possible reason for this?

Question answer: the problem of this case is mainly reflected in the shape of the cavity after pulpotomy. Pay attention to observe the left cavity wall of the tooth X-ray. If it is prepared as usual, it is because the drill breaks the steps formed by the cavity wall and bottom. If you evaluate the quality of root canal treatment, it is necessary to deduct points! However, careful observation of the cave wall morphology of this case shows that this case belongs to the retreatment case, so it is still an ideal case.