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Purpose: The aim of this study was to introduce a newly designed die for ceramometal
restoration, and to compare the dimensional accuracy with the traditional complete-crown
design. Two methods of dimensional accuracy assessment, vertical axial discrepancy and
transverse diametral percentage, were compared. Materials and Methods: Patterns were
prepared from two different die designs—complete crown and ceramometal. Two investments
available for titanium crown casting were used, Titavest CB and T-invest C & B.
Titanium castings were made from each investment with a high-pressure casting machine.
Vertical axial discrepancy of casting was determined by measuring the discrepancy for each
set of wax patterns and their castings on the same die under a traveling microscope. Dimensional
accuracy was expressed as vertical axial discrepancy and by transforming the vertical
axial discrepancy into transverse diametral percentage. Results: Both dies produced undersized
castings with T-invest C & B and oversized castings with Titavest CB. Dimensional
accuracy assessment of the two different types of crown casting design showed no significant
difference in vertical axial discrepancy. Conclusion: Compared to the traditional
transverse diametral percentage calculation, the vertical axial discrepancy assessment is
independent of the die’s dimensions. The two types of investment materials studied resulted
in castings with different dimensional accuracies. Int J Prosthodont 2003;16:13–18.
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