When should a dental crown be replaced? Just like any other appliance in your home, a dental crown may need to be replaced after some time. How long a crown lasts varies from person to person, but there are general timelines you can use as a guideline. Read on to learn more about when you might need to replace your dental crown. A dental crown should be replaced when it becomes loose or falls off. Dental crowns are prosthetic devices that are used to restore teeth. They are made of porcelain or metal and come in different shapes and sizes. Dental crowns can be a temporary fix for teeth that have been damaged due to gum disease, cavities, tooth decay, or trauma (i.e., chipped). Dental crowns can also be a permanent replacement for missing teeth that cannot be restored with dental implants. A dental crown should not be replaced if it is securely in place but the patient notices shifting of their bite; this may indicate an underlying prob...