Semi-adjustable articulator with mounted casts. An articulator is a mechanical device used in dentistry to which casts of the maxillary (upper) and mandibular (lower) teeth are fixed, reproducing recorded positions of the mandible in relation to the maxilla.
The Greek scholar Heron of Alexandria created the earliest known automatic door in the 1st century AD during the era of Roman Egypt. The first foot-sensor-activated automatic door was made in China during the reign of Emperor Yang of Sui (r. 604â618), who had one installed for his royal library.
Our History. AN IMPROBABLE BEGINNING LED TO DECADES OF INNOVATION. Sealed Air started with two engineers and an idea for wallpaper. In 1957, Alfred W. Fielding and Marc Chavannes set out to create a new wall covering by laminating two plastic sheets with air bubbles in between.