Expanded endo tip range for efficient root canal treatment
In order to ensure that root canal treatments are performed as efficiently and atraumatically as possible, Dr Shahrad Nouraie Ashtiani, an oral surgery resident and dentist specializing in endodontics from Hamburg (currently practising in Bremen), Germany, relies on the W&H Tigon+ piezo scaler in combination with the optimally coordinated ultrasonic tip range.
In the following article, Dr Ashtiani outlines three clinical applications in which the targeted use of the W&H endo tip range is described in more detail.
The operation should be performed using a surgical microscope. If none is available, it is advisable to use dental loupes at least. Use of a rubber dam is recommended in all cases and is an indispensable element of a lege artis treatment. When the tips are used in the canal, dental loupes should be employed as a bare minimum at all times. In the case of deep canal preparation for the removal of broken-off canal instruments, the use of a surgical microscope is obligatory, as otherwise the risk of a perforation is too high. Canal instruments and posts can only be removed from the upper canal section without the aid of a microscope.
3E special tip:
Removal of broken root canal instruments
4E special tip:
Preparation of pulp chamber floor
5E special tip:
Shaking out and removal of root canal posts
6E special tip:
Removal of root canal fillings and calcified root canals
Case 1: Primary treatment of a tooth
Following opening of the pulp chamber with a W&H contra-angle handpiece, which also ensures optimal spray cooling, the crown pulp is thoroughly removed. In the next step, the ultrasonic tips are used in combination with the W&H Tigon+ piezo scaler. The settings of the Tigon+ are perfectly coordinated to the tips, making the instrument ideal for this purpose.
The 6E and 4E tips are then used to prepare the cavity floor, round off the canal transitions and expose the canal openings. In very narrow channels such as the MSB2 in the maxillary molars, the 3E tip should be used.
With the 3E and 6E tips it is even possible to prepare the upper sections of the canal conically at the same time. NB: Formation of steps. Applications in the canal should only be conducted by experienced surgeons. The canal can be processed in the same way with the Gates Glidden bur, although this often results in edges at the transition to the cavity floor. Any such edges can be rounded off using the 4E tip.
Following the visualization of the canals, the rounding off of the canal openings, the removal of any dentine overhangs and the preparation of the cavity floor, the canal preparation can be started. There is a whole range of manual and automatic instruments available for this purpose, but the scope of this article does not allow for them to be described in detail. It is particularly important that rinsing fluid is always employed when preparing canals. The canal should be rinsed multiple times after the use of each instrument (including when the same instrument is used each time) and in cases of complex anatomical conditions in order to remove any shards of dentine.
Following preparation right up to the final length and preparation size, the canal is rinsed as per the rinsing protocol. With the help of the 6E tip, the rinsing fluid is repeatedly activated, rinsed out and activated again for 20 to 30 seconds. This procedure is repeated until the rinsing protocol with the different, recommended rinsing fluids and quantities has been completed.
Following this step, the canals are dried and filled laterally or vertically, cold or hot, depending on the options and available materials.
Case 2: Removal of a fractured root post
The canal access is prepared as described for case 1. This should always be performed using a surgical microscope or dental loupes. In order to avoid a perforation, only the upper canal section should be prepared.
The following additional approach is recommended:
- The broken-off fragment or root pin is slightly exposed using the 3E tip.
- The broken-off post is then shaken out using the 5E tip. If the tip does not come loose immediately, the 3E tip should be used again.
- Once it has been successfully shaken out, the canal preparation is performed (see Case 1).
- With regard to the rinsing protocol, it must be borne in mind that due to the different germ spectra associated with each time of revision, 2% CHX should also be used for rinsing in addition to the other rinsing fluids.
- The remainder of the procedure is performed as described above.
Case 3: Removal of a fractured root canal instrument
These treatments should always be performed using a surgical microscope. NB: Via falsa (perforation). The treatment may only be performed once the indication has been confirmed precisely. It is important to be able to estimate the success of the treatment in advance. The surgeon must be able to assess his own skills precisely for this class of indications.
The following approach is recommended for removal of a fractured root canal instrument:
- First of all, the canals are visualized, followed by the revision of any in situ root fill material using the 6E/3E tips.
- Once the gutta-percha has been completely removed right up to the broken-off instrument, the canal must firstly be expanded in a straight line and in its diameter.
- The tip should then be completely exposed on all sides under microscopic control.
- The instrument is now exposed 1-2 mm in the apical direction using the 3E tip. NB: Via falsa (perforation). When using ultrasonic tips there is also a risk that the broken-off instrument tips could fracture a second time. For this reason, it is important to ensure that the preparation is performed in the tooth.
- There are a number of possibilities for its removal, but the scope of this article does not allow for them to be described in detail. However, in the best case scenario, the instrument can be detached using the rinsing syringe once exposed. NB: Renewed risk of instrument fracturing. There is a whole range of other possibilities depending on the anatomy and site.
- The removal is followed by the apical preparation, rinsing as per the rinsing protocol (once again, note that 2% CHX is also used here for rinsing in addition to the other rinsing fluids.
- The remainder of the procedure is performed as already described in Case 1 (see above).