The overall thrust of this work is concerned with the performance of the adhesives used to simulate cementation of gold crowns onto nickel chromium dies under static and dynamic compression. A measurement system, based on the mounting of strain gauges on the outer surface of the crowns, has been developed allowing an indirect semi-quantitative estimate of the state of adhesion.
This paper reports an investigation of the effect of increased total occlusal convergence (TOC) of the nickel chromium dies from 12 degrees to 24 degrees with different degrees of cementation, a) un-cemented, b) partially cemented and c) fully cemented.
Four nickel chromium dies (12 degrees TOC) and five nickel chromium dies (24 degrees TOC) for each convergence were fabricated using the lost wax technique. The axial height of all dies was 6mm. Two miniature gauges were installed on opposing axial surfaces of each gold crown 1 mm above the crown margin. Axial loading and unloading of the crowns was repeated five times for each crown and the values for strain recorded.
The results showed an increase in strain at the axial surfaces with increasing TOC, providing useful design information for the durability of restorative crowns. These findings, along with the findings of earlier work are consistent with a simple model of load transfer between the crown and the die.
|Title of host publication||Medicine Meets Engineering|
|Subtitle of host publication||Proceedings of the 2nd Conference on Applied Biomechanics Regensburg|
|Editors||Joachim Hammer, Michael Nerlich, Sebastian Dendorfer|
|Number of pages||12|
|Publication status||Published - 2008|
|Event||2nd Conference on Applied Biomechanics - Regensburg, Germany|
Duration: 13 Jun 2007 → 15 Jun 2007
|Name||Studies in Health Technology and Informatics|
|Conference||2nd Conference on Applied Biomechanics|
|Period||13/06/07 → 15/06/07|