Abfractions are gum line cavities or ridges on the outer layer of teeth that form near the gumline. They are usually caused by too much pressure on your teeth—often a result of grinding/bruxism, overly aggressive brushing or abnormal bite. Abfractions can cause gum recession which can make the exposed tooth very sensitive, particularly to cold temperatures and sweets, and make them susceptible to cavities. These gum line cavities can also cause bone loss and gum loss. Abfractions can usually either be treated with a filling to restore the tooth, or gum replacement grafts to cover up sensitive exposed roots.