The literature related to failures of CAD/CAM restorations, with emphasis on secondary caries, is presented. A good approximal fit of the restoration is important to prevent plaque accumulation that may lead to secondary caries. CAD/CAM restorations allow inspection of the approximal fit prior to cementation and it may explain the relatively few failures due to secondary caries. The longevity of these restorations approaches that of gold restorations.
Clinical relevance: The requirement for CAD/CAM restorations has advanced to a stage where high quality restorations with excellent anatomy and fit can be produced. The failure rate is relatively low compared to directly placed restorations.