Share Hub — How to Adjust Occlusion in Ceramic Veneers
This step is performed after cementation of ceramic veneers, where adjustment is carried out in centric relations and eccentric movements.
∆ Upper Jaw — Centric Dimension
In the upper jaw, there should usually be no problem in the centric dimension of the jaw relations, except in cases such as veneers with palatal wrap preparation or onlays, where it is preferable that the contact point be one millimeter away from the bond site between the tooth and the ceramic and that the contact be on the tooth; however, if necessary, contact on the ceramic is also acceptable when the above conditions are met.
∆ Lower Jaw — Centric Dimension
In the lower jaw, because the buccal cusp (the functional cusp), the incisal edge, and the labioincisal region of the anteriors play an important role in the centric dimension of the jaw relations, a gentle, uniform contact on the cusp tips and the incisal edge is required. Premature contacts or heavy contacts must be adjusted.
∆ Laterotrusive (Lateral) Movements
In eccentric laterotrusive or lateral movements, on the non-working side no contact is acceptable, neither on the tooth nor on the ceramic.
On the working side, in cases where the patient has canine rise, there should be no contact on the premolars, laterals, and centrals, and in case of interference they are adjusted.
If the patient has posterior group function, the contact on the premolars must be on the buccal cusp tip of the patient's own tooth (veneer with window preparation) and the veneers will have no contact, except the canine veneers, which at the end of the movement, up to the buccal cusp tip of the upper canine, have gentle contact with the rounded cusp tip.
In cases of anterior group function, there is contact other than the canine on the lateral and sometimes the upper central as well; this usually happens when, during the treatment-planning stage, the jaw movements were not checked, or the space for the ceramic was not created during preparation, and sometimes the ceramist adds extra length to the incisal edge; if space was created during the preparation stage, a minor adjustment can be made. It is better not to manipulate and adjust the veneers too much at the incisal edges.
∆ Protrusive Movements
In protrusive movements, the priority is no contact of the posterior teeth and uniform contact of the anterior teeth (incisors); sometimes interferences are seen in the veneers of the lower premolars, which must be corrected from the mesial slope of the lower buccal cusps.
∆ Finishing and Summary
After the corrections are made, the ceramic is polished with special ceramic mounts and kits.
To reduce adjustments after delivery, the initial analysis before starting the preparation is of great importance.