RESUMEN
Objective:To study the coronal microleakage of flared root canal teeth restored with computer aided design and computer aided manufacturing (CAD/CAM)fiber post and core.Methods:60 extracted human mandibular premolars with single canal were divided into 3 groups randomly(n =20).The roots of the teeth were restored with CAD/CAM glass fiber post and core(group A), prefabricated glass fiber post(group B)and gold alloy dowel-and-core(group C)respectively.The specimens were immersed in India ink for 4 weeks.Subsequently all teeth were demineralized,dehydrated and rendered transparent.Then coronal microleakage was ob-served with stereomicroscope.Nonparametric data were analyzed.After that,All the specimens was demineralized completely in nitric acid,Then the interface between the post,resin cement and canal wall was observed and recorded.Results:The microleakage was found in all the 3 groups,group A and C showed less microleakage than group B(P 0.05).Microleakage mostly appeared at the interface between post and resin cement in group A and C,while in group B,it appeared between resin cement and the wall of root canal totally.Conclusion:CAD/CAMfiber post and core demonstrates less coronal microleakage than prefabricated glass fiber post.