Fig.1
The pre-operative bitewing shows a big decay on the distal, cervical side of 16

Fig.2
Pre-operative picture

Fig.3
After removal of the old filling, it’s pretty clear that the situation will require a crown lengthening procedure.

Fig.4
The cleaning of the decay and the preparation of the distal cervical margin, and the crown lengthnening procedure

Fig.5
Tip: It’s mandatory to put the bone crest at 3 mm of distance from the prepared and clean, final cavity margin.

Fig.6
The stitches in place

Fig.7
In the same session the rubber dam is put back in place, and the mesial decay is cleaned too. Note the good isolation obtained thanks to the surgical procedure.

Fig.8
Details after cleaning, the disto-palatal cusp was removed as it was too thin. In fact, we reduce all the cusps that are less than 2 mm. Tip: for composite onlay we need to reduce 2 mm in height too, for lithium disilicate 1 mm is enough.

Fig.9
A build-up is performed,  sealing of the dentinal tubules, and preparing the cavity for an onlay.
Tip: Clean the dentin with glycine powder and decontaminate it with 2% chlorhexidine, then etch the enamel for 20 seconds, and apply a universal adhesive agent on the dentin and on the enamel, in a self etching mode. It works and performs very well and it prevents post operative sensitivity.

Fig.10
Only at this point we can clean the decay on 15 and 17 and do the direct fillings on them. Tip: don’t do them before not to damage them during the preparation of the onlay.

Fig.11
Details of the placement of the sectional matrices and of the wooden wedges.

Fig.12
The direct restorations on 15 and 17 are done with only one body shade (A2 in this case) and brown stains to increase the perception of depth, and it’s finished and polished under dam isolation.
Tip: use again a universal adhesive in a self etching mode, with the selective etching technique to have the best performance without post operative sensitivity.
Tip: finish and polish the restorations under the dam so to have the perfect control without blood and saliva and tissues to move away

Fig.13
Before taking impressions we check the occlusion of the restorations. No corrections are needed.

Fig.14
Details of the impression taken with the stitches in place.
Tip: take a one step two paste impression  to get the best performance of the impression materials with the less distortions

Fig.15
The composite onlay, on the plaster model.

Fig.16
After 48 hours the indirect restoration is tried in, with the stitches still in place. Tip: this will reduce the time of the provisionals and the discomfort of the patient

Fig.17
We proceed with the occlusal check

Fig.18
The rubber dam’s put in place again and the onlay’s tried in with the rubber dam too, before the bonding procedures.
Tip: check it back with the rubber dam in place as it could interfere with the restoration seating

Fig.19
Finishing and polishing under the dam

Fig.20
The occlusal check at the end of the bonding procedure shows no need for correction.

Fig.21
Final check of the three restorations.

Fig.22
Two weeks post operative, there’s a good integration of the restorations of 15, 16, and 17.

Fig.23
Details of the morphology and anatomy of 15, 16, 17.

Fig.24
Details of the restorations. The tissues after two weeks are still healing.

Fig.25
Final bitewing x-ray. The restoration looks accurate in seating and margins.

Conclusions

To restore means to give function and esthetics back to our patients’ teeth. This must be done with accuracy and must last in the long run. We have to follow simple rules and protocols to obtain these goals, with no flight of fancy.
As much as these steps can be feasible, predictable and applicable as much we’d reach the results required.
Universal adhesives nowadays work and perform really well, clinically speaking, and can be used by everyone in the same way. They are not only the future of adhesion but they’re also the present, so use them without fear or doubt.
The author wants to thank Dr. Paolo Marchetti for the surgical procedures and Mr. Sebastiano Nardo for the lab work.

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