Resumen de Impact of design and length on the accuracy of closed tray transfer copings

Elena Roig, Natalia Álvarez-Maldonado, Luis-Carlos Garza, Marta Vallés Rodríguez, José Espona, Miguel Roig Cayón

• The aim of this study was to evaluate the accuracy of two closed-tray transfer copings for implant impressions (a new design vs. an old design) in two different lengths (short and long).

  Four groups of transfer copings (NS - new short, NL - new long, OS - old short and OL - old long) were tested. An epoxy resin model was prepared of missing teeth 1.4, 1.5 and 1.6. Two Alpha-Bio analogues were placed in position of teeth 1.4 and 1.6, at a 10o angulation. Two calibrated operators took 10 closed-tray impressions for each group with polyether in a Rim-Lock impression tray.

  After measuring and comparing impressions, a significant difference was found between the two new transfer copings and the old short transfer coping.

  The new transfer coping design significantly improved impression accuracy. An adequate transfer coping design for the closed-tray impression technique can help to achieve clinically acceptable impressions for two-unit implant supported bridges.