A pinless dental articulator includes a work tray, a retention pocket, and a monorail formed by a plurality of upwardly tapering cylinders which allow jelly or stone to slide out of the retention pocket when the work tray is turned upside down. The work tray has a ledge which stabilizes a rotatable arm that retains the jelly or stone in the retention pocket. A method of using the articulator includes the steps of installing the locking arm onto the stabilizing ledge of the work tray, rotating the locking arm into a closed position on the stabilizing ledge, pouring jelly into the retention pocket, installing a height-adjusting post in the work tray, tightening a fastener against the post in order to keep the post in an upright position, and placing a small tray with at least one negative tooth impression on top of the jelly.