A tooth may be lost if which condition occurs?

A tooth may indeed be lost if a fracture splits the root in an unfavorable manner. When a tooth sustains a fracture, especially if it involves the root, the stability and integrity of the tooth can be severely compromised. A split root can lead to complications, including infection and inability to maintain the tooth within the socket, ultimately resulting in tooth loss. This is particularly critical because root fractures often do not heal well, and the tooth may not be salvageable, necessitating its removal.

In contrast, while untreated cavities can lead to decay and further complications, they often do not result in immediate tooth loss if properly addressed at a later stage. Severe discoloration of a tooth may affect its appearance and could reflect underlying issues, but it does not inherently lead to tooth loss. Extreme temperature changes can cause discomfort but typically do not result in the loss of the tooth unless combined with other more severe factors. Thus, the risk of losing a tooth is directly connected to the structural integrity of the tooth, making the fractured root scenario particularly critical.