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Accuracy of the second pour casts using dual-arch trays.

OBJECTIVE
To compare, in vitro, the accuracy between dental stone casts obtained from the first and the second pour using metallic (Smart) and plastic (Triple Tray) dual-arch trays.


MATERIAL AND METHODS
The impressions were taken using Flexitime® vinyl polysiloxane from a typodont model with a mandibular right first molar prepared for a full crown. Ten impressions were made with each tray and poured using type IV die stone. After 1 hour, the casts were removed from the impressions and, 1-hour later, second pours were completed. The mesio-distal and the buccal-lingual widths at the gingival margin of the prepared tooth on the cast were measured in a perfil projector. The results were submitted to Student's t-test (α=0.05) using SPSS version 10.0.


RESULTS
There was a statistically significant difference between the first and second pours using the plastic tray in the mesio-distal width.


CONCLUSION
It could be suggested that a repeated pour is more accurate using a metallic tray.