Cast metal inlays can be used on molars requiring a
class II restoration instead amalgam and offer a durable alternative.
Because it is known that class II inlays may increase the
susceptibility to fracture, it is important to ensure optimal
performance in selection of the adequate preparation design to reduce
stresses in teeth structures and also in the restorations. The aim of the
study was to investigate the influence of preparation design on stress
distribution in molars with different class II preparations and in cast
metal inlays. The first step of the study was to achieve 3D models in
order to analyze teeth and cast metal class II inlays. The geometry of
the intact tooth was obtained by 3D scanning using a manufactured
device. With a NURBS modeling program the preparations and the
appropriately inlays were designed. 3D models of first upper molars
of the same shape and size were created. Inlay cavities designs were
created using literature data. The geometrical model was exported
and the mesh structure of the solid 3D model was created for
structural simulations. Stresses were located around the occlusal
contact areas. For the studied cases, the stress values were not
significant influenced by the taper of the preparation. it was
demonstrated stresses are higher in the cast metal restorations and
therefore the strength of the teeth is not affected.
[1] Fonseca, R.B.; Fernandes-Neto, A.J.; Correr-Sobrinho, L. & Soares, C.J.
(2007). The influence of cavity preparation design on fracture strength
and mode of fracture of laboratory-processed composite resin
restorations. J Prosthet Dent. 98:277-284, ISSN 0022-3913.
[2] Dejak, B.; Mlotkowski, A. & Romanowicz, M. (2003). Finite element
analysis of stresses in molars during clenching and mastication. J
Prosthet Dent. 90:591-7, ISSN 0022-3913.
[3] Shillingburg, H.T. (1997). Fundamentals of fixed prosthodontics. 3rd ed.
Chicago: Quintessence. p.171-9, ISBN 0-86715-201-X.
[4] Dejak, B.; Mlotkowski, A. & Romanowicz, M. (2007). Strength
estimation of different designs of ceramic inlays and onlays in molars
based on the Tsai-Wu failure criterion. J Prosthet Dent.98: 89-100, ISSN
0022-3913.
[5] Yamanel, K.; Caglar, A.; Gulsahi, K. & Ozden, U.A. (2009). Effects of
different ceramic and composite materials on stress distribution in inlay
and onlay cavities: 3-D finite element analysis. Dental Materials Journal.
28(6): 661-670, ISSN 0109-5641.
[6] Dejak, B. & Mlotkowski, A. (2008). Three-dimensional finite element
analysis of strength and adhesion of composite resin versus ceramic
inlays in molars. J Prosthet Dent. 99: 131-140, ISSN 0022-3913.
[1] Fonseca, R.B.; Fernandes-Neto, A.J.; Correr-Sobrinho, L. & Soares, C.J.
(2007). The influence of cavity preparation design on fracture strength
and mode of fracture of laboratory-processed composite resin
restorations. J Prosthet Dent. 98:277-284, ISSN 0022-3913.
[2] Dejak, B.; Mlotkowski, A. & Romanowicz, M. (2003). Finite element
analysis of stresses in molars during clenching and mastication. J
Prosthet Dent. 90:591-7, ISSN 0022-3913.
[3] Shillingburg, H.T. (1997). Fundamentals of fixed prosthodontics. 3rd ed.
Chicago: Quintessence. p.171-9, ISBN 0-86715-201-X.
[4] Dejak, B.; Mlotkowski, A. & Romanowicz, M. (2007). Strength
estimation of different designs of ceramic inlays and onlays in molars
based on the Tsai-Wu failure criterion. J Prosthet Dent.98: 89-100, ISSN
0022-3913.
[5] Yamanel, K.; Caglar, A.; Gulsahi, K. & Ozden, U.A. (2009). Effects of
different ceramic and composite materials on stress distribution in inlay
and onlay cavities: 3-D finite element analysis. Dental Materials Journal.
28(6): 661-670, ISSN 0109-5641.
[6] Dejak, B. & Mlotkowski, A. (2008). Three-dimensional finite element
analysis of strength and adhesion of composite resin versus ceramic
inlays in molars. J Prosthet Dent. 99: 131-140, ISSN 0022-3913.
@article{"International Journal of Medical, Medicine and Health Sciences:61584", author = "Sandu L. and Topală F. and Porojan S.", title = "Stresses in Cast Metal Inlays Restored Molars", abstract = "Cast metal inlays can be used on molars requiring a
class II restoration instead amalgam and offer a durable alternative.
Because it is known that class II inlays may increase the
susceptibility to fracture, it is important to ensure optimal
performance in selection of the adequate preparation design to reduce
stresses in teeth structures and also in the restorations. The aim of the
study was to investigate the influence of preparation design on stress
distribution in molars with different class II preparations and in cast
metal inlays. The first step of the study was to achieve 3D models in
order to analyze teeth and cast metal class II inlays. The geometry of
the intact tooth was obtained by 3D scanning using a manufactured
device. With a NURBS modeling program the preparations and the
appropriately inlays were designed. 3D models of first upper molars
of the same shape and size were created. Inlay cavities designs were
created using literature data. The geometrical model was exported
and the mesh structure of the solid 3D model was created for
structural simulations. Stresses were located around the occlusal
contact areas. For the studied cases, the stress values were not
significant influenced by the taper of the preparation. it was
demonstrated stresses are higher in the cast metal restorations and
therefore the strength of the teeth is not affected.", keywords = "cast metal inlays, class II restoration, molars, 3D
models, structural simulations.", volume = "5", number = "11", pages = "620-4", }