The life of a crown will depend on how well it is looked after. The crown itself cannot decay, but decay can start where the edge of the crown joins the tooth. It is very important to keep this area as clean as your other teeth, or decay could endanger the crown. Research suggests that crowns last, as an average, for 8 - 15 years before they need remaking. Having said that, proper care and regular check-ups may help keep a crown in function for many more years.