Evaluation the effect of artificial aging on shear bond strengths of a subtractive and additive 3D printing extra coronal restorations.

Abstract

Aims: to evaluate the effect of artificial aging of shear bond strength (SBS) value on extra coronal restoration that prepared by different techniques.

Methods: A total of 48 rectangular-shaped bar prepared in dimensions (18*7*1.5 mm) length, width, and height, respectively, were be fabricated from four different materials: IPS E.max Press, IPS E.max CAD/CAM, ZLS, and 3D printing nanoceramic (n=12 for each material). 24 samples (6 from each material) were undergone thermocycling, A tygon tube placed at the center of intaglio surface of each material with the aid of an orthodontic wax and cemented with resin cement and shear bond strength (SBS) testing performed for the samples.

Results: (SBS) test show that the thermocycling had a lowest impact value on the material (E.max Press) and the technique (conventional technique) than on other materials and techniques. Regarding the impact of materials on SBS, E.max CAD/CAM exhibited the highest bond strength values both before and after thermocycling. In terms of technique, the subtractive method had the highest SBS before thermocycling, whereas no significant differences were observed between the techniques after thermocycling.

Conclusion: Thermocycling had an effect on different materials and techniques; also, the difference in materials according to the working conditions has an effect before and after the thermocycling, and the difference in techniques according to the working conditions had an effect before thermocycling.