Purpose: Accurate implant impressions play a significant role and serve as a starting point in the process of producing good working casts. This study was designed to evaluate the effect of two different impression materials, additional silicone (Enthus) and vinyl siloxanether (EXA'lence), on the accuracy of impressions in parallel and nonparallel implants.
Material and Methods: In this study, two completely edentulous mandibular models were used. Three implants (OsseoLink USA LLC. 4 mm ×9 mm, internal connection type) were placed in each reference model with different angles (0 and 15 degrees). Thirty stone casts were made from each reference model using additional silicone (Enthus polyvinyl siloxane, PVS) and vinyl siloxanether (EXA'lence, VSXE) (n=15 per group) with direct technique. The inter-implant distances were measured for casts using a coordinate measuring machine and the deviations compared to the reference models were calculated. Data were collected, tabulated and statistically analyzed using Student T-test.
Results: In parallel condition, the two materials showed non-significant difference in deformation of (∆ r1 or ∆ r2), while in the presence of angulated implants, vinyl siloxanether (EXA'lence, VSXE) impression material showed more accurate results compared to additional silicone (Enthus polyvinyl siloxane, PVS) impression material.
Conclusion: Within the limitations of this study, in parallel conditions, the type of impression material cannot affect the accuracy of the implant impressions; however, in nonparallel conditions, vinyl siloxanether (EXA'lence, VSXE) impression material produced more accurate casts than additional silicone (Enthus polyvinyl siloxane, PVS) impression material.