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.
doors on historical buildings require wood doors. 2. All interior wood doors shall be solid core, either mineral core where a fire. rating is required, high density particle board core, or wood stave core. 3. Wood doors which are to receive clear or stained finish shall be factory. finished and pre-machined for hardware. Specify that the door edges are fabricated of matching wood to the face. 4. Doors to rooms storing high value items such as computers, scientific equipment, etc. shall have solid doors without vision panels and without adjacent sidelights. 5. The A/E must review door manufacturer list early in the design process