What is the primary use of dental impression trays in clinical practice?

The primary use of dental impression trays in clinical practice is to take impressions of oral structures. Impression trays are designed to hold the impression material in place while it sets, capturing detailed and accurate replicas of a patient's teeth, gums, and other oral anatomy. This information is crucial for creating custom dental devices such as crowns, bridges, dentures, and orthodontic appliances, as well as for diagnostic purposes. The success of many dental procedures depends on the precision of these impressions, making this function of impression trays vital in restorative and orthodontic dentistry.

The other options, while related to dental procedures, do not accurately represent the main function of impression trays in a clinical setting. For example, some dental materials and tools are involved in the preparation or polishing of teeth, but these processes require different instruments and methods. Extraction of teeth is a surgical procedure that involves specific extraction tools and techniques rather than impressions. Thus, the correct answer emphasizes the essential role of impression trays in capturing oral anatomy for accurate dental treatment planning and execution.