Choosing a restorative procedure is often a cause for doubt for the dentist considering the loss of dental tissue and the different type of materials that we can use.
In case of extensive damage and tooth decay indirect restoration are preferred, to also avoid fracture risk through cusp coverage.
Differently, whenever possible, a direct approach must be taken, when talking about restorative procedures in posteriors.
This clinical case shows how to treat teeth with direct and indirect restoration.

Fig.1
Preoperative picture of old composite restorations that have to be replaced for decay and secondary caries.

Fig.2
Cleaning of old restorations and secondary caries and reduction of cusps of 15 to prepare for an overlay.

Fig.3
Cleaning of old restorations and secondary caries and reduction of cusps of 15 to prepare for an overlay.

Fig.4
Direct restoration of secondary caries on 16 and 14 with composite (body and enamel), preparation and build up with composite on tooth 15.

Fig.5
After 10 days from the obturations, before the isolation with rubber dam for the adhesion of the overlay on 15 with dual curing cement.

Fig.6
Isolation of tooth 15 before cementation of the overlay. The tooth was treated with etching of the enamel for 20 seconds and sandblasting of the composite part of the build up.

Fig.7
The lithium disilicate overlay was etched with 5% hydrofluoric acid for 20 seconds, and then it was cemented with dual curing cement.

Fig.8
After removal of rubber dam and polishing.

Fig.9
Final x.ray of the direct restoration and overlays.

Fig.10
Final x.ray of the direct restoration and overlays.
Conclusions
The loss of dental tissue is the main aspect to consider in case of direct or indirect restoration choice, above all in premolar where fracture risk is very high.
Nowadays new techniques and materials can help dentistry in term of precision and esthetic aspects, also in indirect restorations.
Bibliography
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