Choose a matrix (part 2)
Unfortunately, the matrices that we showed on part 1 of this series of articles, are sometimes not tall enough to fulfill all our needs. After many years of searching an alternative to the conventional strips, another choice was found to be accurate and easy to obtain.
In this trauma case, a portion of the incisal edge was chipped, regardless of this situation, tooth 11 had a deficient distal restoration that needed to be replaced not only because of the esthetics but because of shape integration with the contralateral tooth and the high risk of decay underneath itself.
After carefully removing the old restorations and fragile enamel, the distal wall shape has to be planned in order to match a certain harmony of the anterior teeth. In this exceptional case, where we do not have a wax-up at our disposal, the distal wall was built directly with the aid of curved matrices.
Straight matrix strips are still being used to protect the adjacent teeth while etching and bonding. Afterwards it will be removed in order to place the anatomical matrix.
A sectional posterior metallic matrix (Garrison Composi-tight) was placed oriented vertically (with one of it extremes facing gingival) and wedged in order to become stable. Notice how the rounded profile of these kind of matrices seem to adapt to the curved profile of anteriors.
The situation after removing the matrix from the field. The situation seems to be ideal. Despite having great advantages these matrices are paradoxically too long to work and get deformed very easily, especially when condensing composite against it.
The final aspect of the restoration immediately after rubber dam removal.
In another case, where multiple incisal restorations were done, probably the past operator had some issues with straight matrixes, not being able to manage correctly natural incisal angles.
The removal of the old composite restorations, which was very difficult given the fact that the color was very accurate and the bonding in the enamel was very strong, was carefully done with abrasive discs, when applying the right amount of pressure, is easy to only abrade the composite, damaging almost no sound tissues.
The situation after the previous restorations were removed and the teeth are ready to be treated with the bonding procedures.
With the silicone key taken from the wax-up, the palatal walls were constructed respecting the space of the proximal walls in order to let the matrices pass freely.
The construction of the proximal walls is done with this same solution, and one by one with very small increments of material.
A close up of the inside of the matrix, showing how a contour can be easily achieved.
The matrix is removed and the other side of the matrix which is still intact can be used for another tooth, when multiple restorations are done.
After trying many matrix system, there is only one which seems to fulfill most of the clinical needs, we are going to analyze that system in the third article of this series.