Indications for Opening the Contact in Ceramic Laminate Preparation

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In ceramic laminate veneer preparation, the general principle is to be conservative and to preserve enamel, since the presence of enamel produces a more durable and predictable bond. For this reason, under normal circumstances the proximal contacts are not opened, so that the enamel in the proximal area is preserved. However, in certain clinical situations we are forced to open the contact and move the finishing line toward the palatal surface:

1. Presence of Prior Restorations (Class III Composite)

If a composite restoration is present in the interproximal area, the finishing line must be extended beyond the composite and placed on sound tooth structure.

A new laminate veneer should never be placed over an old, unknown restoration; prior restorations must always be replaced, due to bonding problems with old composite and the risk of treatment failure.

Note: if the restoration is very extensive, it is not necessary to extend the preparation so far that it reaches sound tooth structure (since the preparation then shifts from a laminate toward a partial crown). In this case, once the restoration is replaced, the contact is opened and the margin is placed on the new composite at a location that is accessible and can be examined.

2. Presence of a Diastema, Triangular Tooth Form, or Open Gingival Embrasures

In these situations, in order for the laboratory technician to correct these spatial and esthetic issues, the contact must be opened and the finishing line moved toward the palatal line angle.

In these cases, the finishing line in the proximal area should be slightly subgingival (below the gumline) so that the technician can create a better appearance.

3. Severe Color Change or Discoloration of the Teeth

If there is a severe color difference between the existing condition and the final treatment outcome, in order to prevent the laminate margin from showing through and to preserve esthetics, the contact is opened and the margins are moved toward the palatal surface.

4. Changes in Tooth Dimensions and Midline Correction

In cases where we want to change tooth size with the laminate, or correct small midline deviations (in patients who are not orthodontic candidates), opening the contact gives the laboratory the maneuvering space it needs.

5. Presence of Caries

If caries is present in the contact area, opening it to remove the caries, restore the tooth, and move the finishing line toward the palatal surface is mandatory.

Closing message: performing esthetic treatments is excellent, provided that we learn their scientific principles correctly, execute them with high quality, and keep our knowledge up to date.

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