What part of a partial denture provides vertical and horizontal support by contacting a tooth?

The part of a partial denture that provides both vertical and horizontal support by making contact with a tooth is referred to as rests. Rests are components designed to fit onto the occlusal, incisal, or cingulum surfaces of natural teeth. They play a crucial role in the stability of the partial denture, ensuring that it remains securely in place during function while distributing forces appropriately to prevent movement.

Rests help to maintain the position of the denture by providing a solid foundation, which is essential for effective chewing and speech. By serving as a support point, they help to minimize the potential for excess stress on the abutment teeth, aiding in the longevity of both the denture and the natural dentition.

Other components like clasps, frameworks, and bases serve important functions, but they do not provide the same kind of direct vertical and horizontal support to the natural teeth as rests do. Clasps are primarily used for retention, frameworks provide the structure and shape of the denture, and bases serve as the foundation for the artificial teeth but do not contact the teeth in a supportive manner.