Retentive force of pure titanium konus telescope crowns fabricated using CAD/CAM system

The purpose of this study was to investigate the clinical application possibility of pure titanium konus telescope crowns fabricated using a CAD/CAM system. For the CAD/CAM system, Dental Cadim (Advance Co.) was used. For the material, exclusive pure titanium block for this system was used in this experiment. Two types of experimental dies with different heights assumed the konus inner crown and three types of konus outer crowns with different gap widths at the occlusal part were prepared. The outer crown was seated on the inner crown die, and a load was applied perpendicularly to the upper surface of the outer crown for 10 seconds. Pullout test was performed at a crosshead speed of 5 mm/min, and the retentive force was measured. With increase in the height of the inner crown die and the applied load, the retentive force of konus telescope crown increased. Similarly, as the gap width at the occlusal part between the inner crown die and outer crown increased, the retentive force of konus telescope crown also increased.