Generally, there is no special preparation required before taking a 3D digital impression. However, it is important to ensure that the teeth are clean and free of debris, as this can affect the quality of the scan. The dentist may ask the patient to brush their teeth before the procedure. In some cases, a mild retraction of the gums may be necessary to capture the margins of the teeth accurately, especially for procedures involving crowns or veneers. The entire process is noninvasive and comfortable for the patient.