Shereen Salah El-Din, Nadia A Abbas And Nouran Abd-El Nabi,

ABSTRACT
Aim : The Present Study Was Performed To Compare The Dimensional Changes Of Two Elastomeric Impression Materials; Polyether And Additional Silicone Impression Materials When Used In Bounded Partially Edentulous Cases. Methods : Ideal Model Of Maxillary Partial Edentulous Case (Kennedy Class III Modification 1) Was Used As Master Model ; Two Impression Materials Were Used For This Study Divided Into Two Groups; First Group : Ten Impressions Were Taken For The Model With Polyether Impression Material And, Second Group : Ten Impressions Were Taken For The Model With Addition Silicon Impression Material; The Casts Obtained From Each Group Were Subjected To Measurements With Digital Caliper And Computerized Image Analysis Software .

Results: The Result Of This Study Revealed That Addition Silicone Has More Dimensional Stability Compared To Polyether Impression Material. Conclusions : The Dimensional Accuracy Of Casts Obtained From Polyether And Addition Silicon Compared To The Original Model, Was Not Statistically Significant .