If a tooth is lost and only the root is left behind, and if there is a partial crown left and the height of the crown can be restored with porcelain or all-porcelain teeth, it should be preserved as much as possible through timely treatment. This root should be treated with a root canal, followed by a fiber pile resin core restoration, and then a porcelain or all-porcelain crown can be placed on the tooth. If the root is already very short or the broken end has reached a deep position below the gum, even through a very good root canal treatment, it is usually of no use and cannot be connected to a clinical crown from above, nor can the chewing function of the tooth be restored, for this kind of root it is also recommended to extract it as soon as possible, and after 2-3 months of extraction, dental inlay treatment is performed.