What is a common reason for a post to cause a root fracture?

A tight fit of the post is a common reason for a root fracture because it can create excessive stress on the roots of the tooth. When a post is fitted too tightly within the root canal, it can lead to an uneven distribution of forces during function. This overload can exceed the strength of the remaining tooth structure and lead to microfractures or complete fractures of the root.

In endodontically treated teeth, the remaining tooth structure is already compromised, and adding a post with a tight fit can exacerbate these weaknesses. Proper fit and adaptability of the post are essential to ensure that forces are managed effectively and do not lead to further damage. The right balance of retention and stress distribution is crucial for the longevity of the tooth and the success of the restoration.

Other factors, such as the type of material or cement consistency, play a role in the overall health of the restoration but do not directly cause root fractures in the same manner that an improperly fitted post can.