Reciprocating Preparation

1. What is unique about RECIPROC?

It is possible to mechanically prepare the majority of root canals with only one mechanical instrument. It is possible to eliminate the use of initial hand filing in most cases. The risk of instrument fracture is minimised due to the reciprocation motion and the instrument design. Root canal preparation with RECIPROC® is easy to learn compared to rotary systems.

10. Why do I not need to start the RECIPROC preparation with a smaller instrument or use a Crown-Down-Method with several RECIPROC instruments?

The reciprocating technique is a crown down technique but with only one RECIPROC® instrument advancing in a corono-apical direction. With the traditional crown down method with rotary instruments, several instruments have to be used because it is impossible to bring the larger instruments used in the coronal part of the canal to full working length. The design of the RECIPROC® instrument together with the reciprocating technique enables preparation of the root canal with only one instrument.

11. Is there a danger of transporting infected tissue and dentin to the apical area when using the RECIPROC technique?

No. There is a reverse movement which transports debris out of the canal. With the reciprocating technique the instrument advances apically in sets of three pecks (see user brochure and user card). After each set of three pecks the instrument is removed and the flutes cleaned of debris. Additionally after each set of thee pecks, the canal is flooded with sodium hypochlorite. This ensures that debris produced in the upper and middle thirds of the canal is removed before taking the RECIPROC® instrument to full working length.

12. Are the settings in the VDW.Silver RECIPROC motor critical?

Yes, RECIPROC® instruments have an individual elastic limit. The elastic limit is the limit at which the instrument will fracture if it is bound in the canal. It is important that this elastic limit is not surpassed. Specific angle settings for RECIPROC® have been established and the VDW.SILVER® RECIPROC® motor has been tested to ensure that it accurately reproduces these angles.

13. Can severely curved canals be prepared with RECIPROC?

Yes. The forward and reverse movement of the reciprocating motion allows the RECIPROC® instrument to advance gradually around a severe curvature. Additionally, the centring ability of RECIPROC® when used in reciprocation together with the flexibility (related to the use of M-Wire®, which is more flexible than traditional nickel-titanium, and the design of the instrument) enables the preparation of severely curved canals.

14. Can I prepare oval canals with RECIPROC?

Yes, the motion used with the reciprocating technique is a picking motion. However, RECIPROC® can also be used additionally in a brushing motion to reach parts of the canal which are not reached with the picking motion.

2. Is RECIPROC appropriate for new NiTi-users or for advanced users?

It is a system for both. New users will like it because it is a very simple technique to master and it is easy to learn. Experienced users will like RECIPROC® because it is faster compared to rotary systems. The preparation shape achieved with RECIPROC® is suitable for cold and warm filling techniques.

3. How many times can I use RECIPROC instrument?

One RECIPROC® instrument does the job of three to five instruments of a continuous rotary system and the RECIPROC® instruments are designed for single treatment use, maximum one molar. Additionally, if an instrument is subjected to extreme stress during the treatment, e.g. an extremely curved or narrow or calcified canal, it may be necessary to discard it earlier. This is, of course, also the case for continuous rotary instruments. As with continuous rotary instruments, check instruments visually for wear after each use. Discard instruments showing any kind of wear.

4. With RECIPROC I can prepare a root canal with only one instrument, but am I trading quality for convenience?

No. RECIPROC® offers all the advantages attached to preparation of a root canal with only one instrument and the possibility to eliminate the use of initial hand filing in the majority of cases without the loss of quality.

5. Do I need to clean and sterilize RECIPROC instruments before using?

No. RECIPROC® instruments are sold in pre-sterilised blister packaging and can be used direct from the package.

6. Why are RECIPROC instruments for single use only?

The RECIPROC® system is designed for convenience. The instruments are delivered ready to use, pre-sterilised in blister packaging and should be simply discarded after use, making work flow RECIPROC® more efficient; eliminating the need to clean and sterilise instruments, considerably reducing the risk of contamination to office personnel and eliminating the risk of cross contamination to patients. One RECIPROC® instrument does the job of several hand and regular continuous rotary instruments and is therefore subjected to more stress. Metal fatigue has been shown to be a frequent cause of instrument separation. Limiting instrument use to max. one molar reduces this risk. The plastic band on the instrument shaft deforms if the instrument is autoclaved so that it cannot be re-used. This safety feature protects against metal fatigue caused by over-use.

7. What is the reciprocating movement?

The reciprocating movement is the most basic backwards and forwards movement that we are used to using with hand files. In the case of RECIPROC® we are using a very precise mechanical reciprocating movement. The angle in the cutting direction is greater than the angle in the reverse direction, so that the instrument is always progressing forwards. The reverse angle allows the instrument to be freed to ensure that the elastic limit of the instrument is not met or surpassed. One complete rotation of 360° is completed in several reciprocating movements. The RECIPROC® setting in the VDW.SILVER® RECIPROC® motor has been selected and tested specifically for RECIPROC® instruments.

8. What are the advantages of the reciprocating movement?

In reciprocation, the instrument stays centred in the root canal. Large instruments with a large core can negotiate even narrow and strongly curved canals, enabling mechanical preparation of the root canal with only one instrument.

The angles of reciprocation are precise and specific to the design of the RECIPROC® instrument and to the VDW.SILVER® RECIPROC® motor. They are designed to be smaller than the angle settings where the elastic limit of the instrument would be met, thus minimising the risk of instrument fractures.

9. What makes the reciprocating preparation safer than rotary preparation?

With correct use of the reciprocating technique, RECIPROC® and the correct motor settings can minimise taper lock and fracture caused by excessive torsion because the angles of the VDW.SILVER® RECIPROC® motor are designed to be smaller than the angle settings where the elastic limit of the instrument would be met. RECIPROC® instruments are used in a single treatment for a maximum of one molar, thus limiting instrument separation due to material fatigue, not to mention the elimination of cross contamination to patients.