A properly designed restoration that maintains a good occlusal relationship between opposing teeth will improve restoration success and reduce its failure.
In this regard, several questions need to be addressed:
Should the occlusion be changed?
In general, this is the case when there is a full-mouth rehabilitation or when the original occlusal scheme is unstable and unsatisfactory. In this case, the centric relation is the starting point and should be properly communicated to the lab, including the desired vertical dimension of occlusion
Heavily worn dentition often asks for an increase
in the vertical dimension of occlusion
Image: courtesy of Pieter-Jan Swerts, Belgium
Are there parafunctional habits present?
Signs and symptoms of bruxism or other destructive habits include wear facets and chipping or fractures. Parafunctions may considerably challenge a restoration and this should be considered when selecting the appropriate restorative material. Monolithic restoration surfaces are preferred to avoid chipping. To achieve an aesthetic result, monolithic restorations can be characterised with Initial IQ Lustre Pastes ONE and Initial Spectrum Stains. White zirconia can first be coloured with Initial Zirconia Coloring Liquids, preventing the formation of noticeable white ‘optical holes’ within the restoration.
In patients with para-functional habits, an occlusal splint is always indicated for protection of the restorations and teeth.
Monolithic restorations are preferred
in case of heavy occlusal loads.
Image: Initial Zirconia Disk crowns,
characterised with Initial IQ Lustre Pastes ONE
Is the restoration implant-supported?
While teeth can make micromovements owing to the periodontal ligament, the contact between an implant and the bone is rigid. Therefore, occlusal contacts should be relieved when the biting force is light. When biting with strong force, the contacts should be evenly distributed between the restoration and the teeth. A long centric occlusion provides the freedom needed to avoid undesirable interferences.
Heavy occlusal loading should be mitigated to avoid early failure of prosthetic rehabilitation. The occlusion should be analysed before the start of the treatment.
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