Laminate veneers in premolars. A 3-D FEA using µCT data

Objectives: Using 3-D finite element analysis (FEA) and µCT data, the aim of this study was to evaluate the behavior of a premolar restored with laminate veneer varying the buccal cusp reduction.

Methods: 3 3-D FEA models (2 maxillary premolar and 1 lateral incisor) were built using µCT data. All models were restored with a feldspathic laminate veneer (Solidworks). The lateral incisor was used as a control. The same tooth reduction (0.5mm) was used in all models. The buccal cusp reduction of premolar followed two configurations: Cc - buccal cusp completely covered by veneer; and Pc - buccal cusp partially covered. The loading (150N, in 45°) was applied on the incisal edge of the lateral incisor, and on the buccal cusp of each premolar. Appropriate boundary condition was performed, and ANSYS (10.0) was used to obtain the stress fields (maximum principal stress - σmax) for the laminate veneer structure and the resin luting cement layer.

Results: The premolar with the Pc configuration showed the smallest σmax variation in the laminate veneer structure (-4.14 to 12.7), and both options, Cc and Pc, showed the smallest σmax variation in comparison with the lateral incisor (-35.4 to 99.2MPa). The premolar with the Cc option showed the smallest σmax in the resin luting cement layer, moving the peak of σmax a little far from the finishing line. The σmax was higher in the resin luting cement of the lateral incisor in comparison with pre-molars.

Conclusion: The laminate veneer and the resin luting cement layer showed an adequate behavior when veneer was applied in premolars. The highest σmax showed by lateral incisor does not represent a risk of failure. Additional non-linear studies should evaluate the influence of veneer and tooth reduction thickness for the lateral incisor, and the variation of loading condition for premolars. CAPES#2325-05-5