Marginal Adaptation of CAD/CAM All-Ceramic Crowns Made by Different Impression Methods: A Literature Review

All-ceramic crowns for teeth are widely used for restoring teeth. Stone casts have been made from conventional impression methods; however, newer techniques have made this process easier and faster for both the patient and the practitioner. Laboratory CAD/CAM technology mainly involves scanning the die stone, while other systems permit impression or intraoral scanning; however, one major concern remaining is the marginal fit of the restorations made using different methods for recording the prepared teeth. This study aims to review studies evaluating the marginal fit of all-ceramic crowns manufactured by CAD/CAM systems using different extra- and intra-oral scanners compared to conventional impressions.