Single blinded in-vitro study comparing microleakage between CAD/CAM crowns milled out of feldspathic ceramic and resin nano ceramic, cemented with three resin cements

摘要

Background : Studies on microleakage of Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) crowns are abundant. However many of them are inconclusive, especially those using self adhesive cements . Aims: To compare the microleakage between CAD/CAM crowns milled out of feldspathic ceramic and resin nano ceramics, cemented with three resin cements. Materials and Methods : Crown preparation was made on 54 extracted human premolars. Impressions were captured optically using CEREC 3D machine intraoral camera, and crowns were milled from feldspathic ceramic (CEREC? Blocs PC, VITA) and resin nano ceramic (Lava? Ultimate CAD/CAM Restorative, 3M ESPE) blocks. The crowns were then cemented with three cements (n = 9); RelyX? U200 Self-Adhesive Resin Cement (3M ESPE); NX3 Nexus ? cement with two-step etch-and-rinse adhesive (Kerr Corporation) or three/multistep etch-and-rinse resin cement, Variolink? II/Syntac Classic (Ivoclar Vivadent). The specimens were kept in water for 24 hours, thermocycled, and then soaked in methylene blue dye for 24 hours, before being sectioned mesiodistally. Microleakage was assessed using a fivepoint scale using stereomicroscope. Statistical analysis of the data was carried out using ONEWay ANOVA. Results: CEREC? Blocs PC crowns showed significantly less microleakage (p 0.001) compared to Lava? Ultimate. RelyX? U200 showed significantly lower microleakage (p 0.001) compared to other cements. Combination of Lava? Ultimate crown cemented with RelyX? U200 showed the least microleakage (p 0.001 ) . Conclusions: The microleakage scores were affected by the types of crown and cements.