Over time, any filling can crack. This can be caused by an injury, too much biting pressure, grinding, or nighttime teeth clenching. In addition to these physical causes, the same decay process that created the need for a filling can cause additional tooth structure to be lost, compromising the restoration. This is especially prevalent when the tooth has been restored for a non-car cervical lesion as the filling is not protected by the natural tooth. Like a traditional restoration, if allowed to progress any cracks in the restoration can deepen and expose teeth to damage, making it weaker, more sensitive, and potentially prone to decay and tooth loss. In the case of a non-car cervical lesion, these cracks can occur below the gum line. Even small cracks can allow bacteria into the tooth and gums causing decay or infection leading to further complications. In situations where filling material of a non-car cervical lesion is compromised, it's critical to work with your doctor to address the issue quickly before serious tooth structure or gum damage occurs.