The purpose of this study was to evaluate the marginal and internal fit of all-ceramic crowns fabricated using the Decsy CAD/CAM system.A master die of maxillary first premolar was measured, and experimental crowns were fabricated. Four conditions were established by combining two convergence angles (4° and 12° ) of the abutment with two different luting space settings (15 pm and 55 ;u m) . The results showed that the experimental crowns had a marginal gap of 42 to 56 pm. When the luting space setting was 15 ,um, the internal gap was 85-88 pm; when the setting was 55 pm, the internal gap was 126-138 pm. The marginal gap for each experimental crown met the clinically acceptable criterion.

It is suggested that the new self-adhesive resin cements exhibited a favorable bonding capability and mechanical properties.

No abstract

When sandblasted at a pressure of 0.4MPa, the zirconia specimens developed a strong bond with the tooth-colored porcelain, regardless of the type of porcelain.

In this study, the effect on the fracture load of inlay-retained composite fixed partial dentures（FPDs）caused by reinforcing them with fiber-reinforced composite（FRC）in different positions was examined. Experimental FPDs were fabricated using Estenia/EG Fiber（Kuraray Medical） . Pontic reinforcement was then performed in one of the following three ways: reinforced the central area in a single line or in double straight lines, or reinforced the bottom in a curved line. The finding was that, when the area ranging from the connector to the bottom of the pontic was reinforced with FRC in a curved line, the fracture load of the FPDs tended to become higher. In addition, the FPDs fractured mainly at the veneering composite of the connector area. Based on the results of this study, it was concluded that reinforcement using FRC is effective, and that the veneering composite in the connector area needs to have sufficient strength to prevent the fractures.