Structural integrity of a Maryland dental bridge

Lopes I.
Correia A.
Viriato Ramos N.
Vaz M.A.P.
Reis Campos J.C.
Couto Viana P.

Abstract:

Maryland dental bridges were developed in the ’70 of the last XX century. These are prosthetic rehabilitations build with a middle pontic and two lateral wings that are bonded to tooth structures. However, lack of structural integrity did not allow the use of these prosthetic rehabilitations for a medium-long time. Due to the evolution of dental materials, mainly dental adhesives/cements and ceramic frameworks, these bridges are being reintroduced in the dental clinical practice. Although, there’s a lack of research and clinical papers on the scientific literature that supports this feature. In this way, we’ve designed a methodological approach to do a mechanical analysis of these dental bridges in order to contribute with evidence that supports its clinical application. By importing a 3D design from a Maryland bridge developed in a dental CAD-CAM software, we have built a mesh (Ansys 15.0; 39998 tetrahedral elements and 23552 nodes) that allowed us to apply the finite element method in order to do a numerical analysis of its mechanical features. The loads that were applied resembled masticatory loads, with a vertical and oblique direction. Our results revealed higher von Mises stresses in the connector’s areas of the Maryland bridge, where the pontic element unifies with the wings that is bonded to the adjacent tooth, that may be critical depending on the dental ceramic that is used in this bridges. Geometrical optimization procedures were then developed to reduce the stress in these areas.

Publication details:

2nd International Conference of the International Journal of Structural Integrity