Precision of the milled full-arch framework fabricated using pre-sintered soft alloy: A pilot study

This study aimed to evaluate the marginal discrepancy of full-arch frameworks in implant-supportedprostheses fabricated using pre-sintered soft alloy (PSA). MATERIALS AND METHODS. Full-arch metalframeworks were fabricated on the edentulous implant model using casting alloy (CA), fully-sintered hard alloy(FHA), and PSA (n = 4 in each group). To evaluate the misfit of the framework to the abutments, the absolutemarginal discrepancy (AMD) values of the frameworks were measured in cross-sectional images that had beendrawn as part of the triple-scan protocol. The AMD values were compared among the tested alloy groups usingthe Kruskal-Wallis test, with a post hoc Mann-Whitney U test (α=.05). RESULTS. The FHA and PSA groupsshowed lower marginal discrepancies than the CA group (P<.001). However, the FHA group did not differsignificantly from the PSA group. CONCLUSION. Soft alloy milling is comparable to hard alloy milling, and it ismore precise than casting in terms of the marginal fit of implant-supported, full-arch prostheses.