Shawn Parisien from Watersedge Dental Laboratory shares a few tips on the importance of tray selection for taking alginate impressions.
Alginate impressions play an important role in dentistry on a day-to-day basis. For this reason and to ensure the accuracy of impressions, tray selection is an essential consideration. Several stock trays exist; however, some types of trays are better for polyvinylsiloxane impressions and others for alginate.
Distortion and lifting of the impression material is a common issue when removing alginate impressions/trays from a patient’s mouth. To minimize both, trays used for alginate impressions should be rigid and have multiple and good-sized perforations to help “lock-in” the material.
Cross-arch distortion or lifting of the alginate will be evident when prostheses such as nightguards, orthotics or cast frameworks will improperly seat in the patient’s mouth but, will fit “perfectly” on the master models.