Aim: The performance of three elastomeric materials for the open monophase implant impressions technique was tested under the following clinical conditions: polyether (IM) and vinylsiloxanether without (ID) and with additional simultaneous splinting of the implant impression copings with a higher shore hardness A-silicone (IDF).
Materials and Methods: The three test groups, IM, ID, and IDF, were randomly allocated 10 test subjects with three to five implants each. The impressions were analyzed regarding the subjective clinical assessments with 11-point rating scales by the dentist, the patient, and the dental technician, as well as to the comparison of these assessments with the objectified clinical fit of the manufactured crowns based on standard clinical evaluation criteria. The three groups were statistically analyzed on the basis of the hypothesis of non-inferiority of ID versus IM and IDF versus IM (alpha < 0.05).
Results: The results of the study showed the objective clinical fit of the dental prostheses made using ID being comparable to the results obtained with IM. Compared with ID and IM, the precision of fit attained with IDF was reduced, although the subjective dentist assessments of IDF were in parts significantly better than those of IM and ID (p = .015). A statistically significant superiority of ID in comparison with IM could be determined with regard to the subjective ratings of the taste by the test subject (p < .01), of the handling (p < .001) and of the precision details of impression (p = .012) by the dentist, and of removing the plaster model from the mold by the dental technician (p = .017).
Conclusions: The overall results of the vinylsiloxanether material in terms of the patients', dentists', and dental technicians' assessments proved to be equivalent or superior to those of the polyether material. The IDF technique cannot be recommended for this application.