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Post crowns: a review.

Summary. This review considers the mechanical and biological principles which apply to the design and construction of post crowns. These principles, together with the results of laboratory studies and clinical surveys suggest that post retention should not be gained at the expense of sound root structure, and that while posts in root canals may make teeth more resistant to fracture than their unrestored counterparts, their presence can cause catastrophic root fracture. The cemented, cylindrical post has the highest reported success rate. New designs of threaded cylindrical posts show promise, but do not have the backing of substantial clinical studies.