Influence of Repeat Pours of Addition Silicone Impressions on the Dimensional Accuracy of Casts

Making an impression represents a critical step in processing and fitting of a dental prosthesis. The definite impression should be accurate to fabricate restoration with ideal marginal fit, internal fit, interproximal contacts and occlusal contacts.The impression materials are used to register or reproduce the form and relations of the teeth and the surrounding oral tissues. Dimensional accuracy and stability are theprimary requisites of an impression material. 

Repeat Pours of Addition Silicone


Accuracy of an impression depends on properties of impression materials like thermal contraction, polymerization shrinkage, presence of volatile by products, elastic recovery, bulk of material and impression technique used. Other factors which influence the accuracy of an impression are tray material, space between tray and tooth preparation, storage conditions, relaxation of stresses caused by the use of non-rigid trays, excessive seating pressure, too slow removal from the mouth or an impression removed before the polymerization is complete. Read more...........................


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