A system for making dental impressions is provided. The system includes a first dental tray and an adjustable dental tray mount for maintaining the first dental tray in a fixed position relative to an upper dental arch of a patient. The adjustable dental tray mount is capable of being mounted on the patient's head, neck or shoulders. The system further includes a flexible tooth separator with a tape-like structure and with a width equal to or greater than a distance from a tooth margin line to a gum line of a tooth of a patient. The system further includes a second dental tray, an adjustable dental tray mount for maintaining the second dental tray in a fixed position relative to a lower dental arch of a patient, and spacing structures to maintain the first dental tray and the second dental tray in position when simultaneously applied to the patient's teeth.