Fig.1
After the RCT a fiber post was cemented and a composite build up was done to seal the tooth. Residual enamel was thick and good, so we decided to only proceed to cusp coverage by fabricating an overlay.

Fig.2
The shade for the indirect restoration was taken before preparing the cavity.

Fig.3
The tooth was prepared to achieve complete cusp coverage as it wasn’t vital, and neighboring teeth were polished.

Fig.4
A digital scan was taken, here you can see a screenshot from the .stl file and details of the preparation without the high definition

Fig.5
CAD file before the project showing contact points

Fig.6
CAD design showing unchanged occlusion on the neighboring teeth, and the onlay project.

Fig.7
After CAM processing, check of the physical wax project.

Fig.8
A pressed lithium disilicate overlay was fabricated and then colored and polished.

Fig.9
Isolation with rubber dam before adhesive cementation.

Fig.10
Try in was carried out under rubber dam isolation to check proximal and marginal fit.

Fig.11
Marginal adaptation was checked on all sides.

Fig.12
Enamel and composite build-up were etched using 37% orthophosphoric acid.

Fig.13
A universal adhesive system (Scotchbond Universal, 3M) was used for bonding.

Fig.14
The surface of the overlay was treated using hydrofluoric acid, polish and adhesive.

Fig.15
Heated composite (A3 Filtek Bulk One,3M) was used for cementation.

Fig.16
After light curing and excess removal, before finishing.

Fig.17
Here you can see how similar the final outcome is in reality compared to the digital project.

Fig.18
At check-up, 10 days later. Integration is satisfactory.

Fig.19
At check-up, 10 days later.

Conclusions

Adhesive indirect restorations are an excellent solution to give stability and resistance to endodontically treated teeth while saving sound tissue.
Using the correct build-up technique it is possible to preserve healthy enamel. New technologies and materials allow dentists to work in an aesthetic and accurate way.
Credits
Thanks to DT Alessandro Arnone for the fundamental contribution.

Bibliography

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