Crown lengthening is a procedure to increase the amount of tooth extending from the gum line. This procedure is required to increase the amount of tooth so that a new crown or restoration can be placed. Crown lengthening is often needed where there is a crack, tooth decay, resorption or extreme wear. It is a necessary step to ensure that the final restoration fits appropriately or to avoid gum problems that can occur when restorations extend deeply under the gum line. Following the crown lengthening procedure, patients usually wait six to twelve weeks before proceeding with the final restoration.