What phenomenon involves the underlying resorption due to heavy orthodontic forces?

The phenomenon of undermining resorption is associated with the resorption of tooth roots due to the application of heavy orthodontic forces. This type of resorption occurs when a localized area of the bone around the tooth root is subjected to significant pressure, typically from orthodontic appliances.

When high forces are applied, the periodontal ligament experiences compression, leading to ischemia in the area. This loss of blood supply can trigger osteoclastic activity, resulting in the resorption of bone in the vicinity of the tooth root, thereby allowing for the tooth to move. Undermining resorption is characterized by this active and localized resorption beneath the bone surface, which stabilizes the root’s position during tooth movement.

In contrast, other types of resorption presented in the choices refer to different mechanisms. Apical resorption generally refers to the resorption occurring specifically at the apex of the tooth, which may be a consequence of both orthodontic treatment and other factors such as dental trauma or chronic inflammation. Surface resorption pertains to a more generalized resorption of the tooth surface due to physiological or pathological conditions rather than the localized response seen with undermining resorption. Localized resorption is less specific than undermining resorption and may not necessarily imply the same pathological