However, the images may be larger or smaller than the actual objects, which disturbs the precise placement of preformed metal posts, since direct digital radiography system can be influenced by many factors.

Metal preformed crowns with nickel chromium alloy were made by punching method to restore fifty-nine teeth of fifty-five children.

Objective\ To explore the effect of metal post and amalgam corn for the restoration of posterior tooth defect.

[Methods]After root canal therapy of 32 extracted maxillary central incisors was performed,the crowns of these teeth were amputated,then all these teeth were restored with two kind of fiber post-core-crown systems and metal post-core-crown system.