Fig.1
Pre-operative x-ray. In this 2D-view you can only see the incomplete endodontic treatment, but not the coronal fracture.

Fig.2
As a first step, a flap was elevated to visualize the margin, and to try and achieve isolation for root canal retreatment.

Fig.3
If the margin is visible, and the gum is open, you can try to put the dam on and, of course, this is the result. The aim is to stabilize the dam below the margins.

Fig.4
Often, with an additional clamp and/or something like a spatula you can obtain the complete isolation of your field.

Fig.5
A retraction cord may help to keep the dam down, to ensure a suitable setting to elevate the deep margins.

Fig.6
After achieving isolation, two matrices (Polydentia) were placed and propped with two liquid dam spots in order to achieve an anatomical margin elevation, and not just straight walls.

Fig.7
Composite Deep Margin Elevation before removing the matrices.

Fig.8
After refining the peripheral margin elevation, full attention could be paid to the endodontic re-treatment and the following build up.

Fig.9
Space for the post can be left in the distal root when needed. The accesses to the mesial canals were marked with white flowable composite.

Fig.10
The build up was finished and prepared for an indirect overlay restoration.

Fig.11
Digital Impression.

Fig.12
Try-in of the overlay to evaluate the accuracy. The Condensa instrument (LM Arte by StyleItaliano) is very useful to keep restorations in place during try-in.

Fig.13
A retraction cord may be really helpful in improving isolation.

Fig.14
Before starting the adhesive procedures it is mandatory to thoroughly clean the surface of the tooth by air flow, or by brushing it with pumice paste.

Fig.15
Selective enamel etching

Fig.16
These are the steps for overlay conditioning before cementation: etching, cleaning, bonding and warm composite placement.

Fig.17
Overlay placement with the warm composite flowing out the entire margin to ensure filling of the whole cementation surface.

Fig.18
The Fissura instrument from LM is very useful to remove the excess material while keeping full vision.

Fig.19
Polishing the interproximal margins is mandatory for the papilla’s healing after cementation. A reciprocating handpiece is a very precise and effective tool to achieve perfect proximal finishing.

Fig.20
Post-operative picture shows great integration of overlay restoration.

Fig.21
Post-operative x-ray after root canal retreatment and overlay cementation.

Fig.22
Lateral view, color integration and gum healing after 7 days.

Conclusions

Some cases initially seem very complex, yet sometimes it is sufficient to be able to isolate with the rubber dam, even by elevating a simple surgical flap, which completely changes the initial perception of a clinical case.
Once the isolation is complete, adhesive protocols can ensure long term success.

Bibliography

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