Acquisition requirements for digital impressions
The digital intraoral scanner is used to collect high-quality digital impressions, and the final shape of the tooth preparation is required to meet certain requirements:
1. The preparation should meet the requirements of a standard all-ceramic restoration, with clear edges and a smooth and smooth surface. The surface of the preparation should not have sharp protrusions or grooves, too deep nail holes to obtain a clear image, and at the same time it will make it difficult to make a restoration.
2. The tip of the tooth should have a space of more than 1.5mm, and the central fossa of the posterior teeth should ensure a repair space of more than 2mm.
3. Utilizing the inlays retained by the medullary cavity, the medullary cavity is prepared into a box shape to increase retention, and the polymerization angle of the side wall of the medullary cavity is prepared to be 2 ° -5 °, thereby improving the friction retention.
4. When taking images, the edges of the preparation should be exposed as much as possible. It is recommended to use mechanical gingival retraction to expose clear and accurate edges of the preparation.