What is the point around which a body rotates during movement called?

The point around which a body rotates during movement is referred to as the center of rotation. This concept is crucial in understanding the mechanics of movement and force application in various contexts, including orthodontics. The center of rotation is essential for analyzing how teeth move in response to applied forces from orthodontic appliances. When an orthodontist applies force to a tooth, this point helps in predicting the direction and extent of movement.

In orthodontics, the center of rotation influences how forces applied to the bracket and archwire system result in the desired tooth movements, including tipping, lingual or labial movement, and bodily movement. This understanding allows practitioners to strategically plan treatment and achieve optimal tooth alignment.

The other terms, such as center of mass and center of resistance, relate to different concepts of force and balance. The center of mass is a physical concept denoting the average position of all mass in an object, while the center of resistance refers to a point in the periodontal ligament around which a tooth can be expected to resist movement. Center of force does not specifically pertain to rotation, but rather to where a force is applied. Each of these plays a role in the mechanical understanding of orthodontic systems, but the center of rotation is specifically key to the kinematics