Pages 377-383, Language: EnglishLiou / Nicholls / Yuodelis / BrudvikThe accuracy of replacing three manufacturers' (Dental Imaging Associates, Implant Innovations Inc, and Steri-Oss) tapered transfer impression copings into impressions made with two different materials (Impregum F and Extrude) was evaluated. Five operators replaced these copings into the elastomeric impression materials. The angular deviations (replacement error) of the copings between the control (original) position and the replaced position in the impressions were evaluated. It was found that no one coping could be replaced into the impressions accurately and consistently by all five operators. However, there were significant differences in replacement accuracy between the three copings. Lower angular deviations were found for the Steri-Oss and Dental Imaging Associates copings when compared to the Implant Innovations coping. There was no significant difference in replacement accuracy between the two impression materials.