A simple trick for a sharp apical barrier placement
Fig. 1

Another common mistake is to place the matrix too far beyond the apex and this leads to a obturation with overfilling.

A simple trick for a sharp apical barrier placement
Fig. 2

To test what is the best method for positioning the resorbable matrix has been created an experimental model which simulates a large lesion, namely the worst situation that the operator can meet. In addition creating this model it was born the idea of being able to use the apex locator connected to the plugger to position the matrix in the best way possible.

A simple trick for a sharp apical barrier placement
Fig. 3

A 3D printed was selected and one root was cut simulating an open and reabsorbed apex. The final prepared diameter of the apex was carried to 0.70. The tooth was subsequently inserted in a closed system in order to put in contact rootsct with a high-density elettroconductive gel. Through a metal rod positioned in touch with the gel, apex locator is now able to work as in vivo conditions.


The attached video shows how placement of the matrix can be simplified by the use of an apex locator and how the operator is facilitated during this challenging procedure which is not always so predictable. In the second part of video the first test is performed in vivo to demonstrate how this procedure is feasible and repeatable with very little effort.


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