Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 1

In the first lower molar an X ray can often show a bone loss between roots and diagnosis is easier than other teeth.

Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 2

The MTA sandwich technique is the one that i personally reccomand for this kind of perforation and it has been well described by Fabio Gorni in this article But what's the equipment? 1) MTA is my choice material for perforation repair and numerous case reports exist in the literature showing excellent healing results with MTA. 2) The MAP (Micro-Apical Placement) System, provides an efficient method for placing repair materials and is the only one device that lasts over time. It has lot of tips,steel and NiTi, that can satisfy all the requirements. I love the NiTi tip because i can bend it as i want. 3) Paper points 4) One gutta cone 5) One plugger 6) One plastic carrier (usually 40 or 60) 7) One Endo Explorer (Dg16)

Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 3

As accurate detection of root perforations and determination of location are crucial to the treatment outcome. A paper point is enough and the appearance of blood in the middle part of it is the perfect sign for a right diagnosis, detection and location of a perforation.

Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 4

The second step is represented by a conventional RCT, but obturation is done with last part of a guttapecha cone, starting with warm gauutapercha condensation deeper than the perforation level, avoiding any contamination of perforation area with sealer and GP. A plugger is used for GP condensation

Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 5

During the third step MTA is positioned with MAP system. The system consists of a stainless-steel or NiTi applicator with a bayonet catch for several exchangeable applicator cannulas (needles). Inside the cannula there is a plunger made in polymer that is longer than cannula providing a complete extrusion of internal material. The MTA can be taken from a dispenser thrusting the tip into the repair material and placed inside the canal in a sharp way pressing syringe piston to expel the material. An endo Micro Brush can be used to gently pack the MTA or a plastic carrier can be used for a stronger condensation. MTA must be placed to all the extension of perforation.

Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 6

The last step is rappresented by backfilling the coronal part with GP or composite material in a second visit.

Fab Lab: video tutorial of MTA Sandwich Technique
Fig. 7

The complete case with 6 years follow-up

Conclusions

Right techniques and right materials and devices ensure good results and success over time. The MTA sandwich technique is a safe and repeatable procedure that must be considered for root canal perforations repair.

Bibliography

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