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Purpose: The present in silico study evaluated the behavior of titanium dental implants associated with abutments in zirconia and monotype zirconia implant using finite element analysis (FEA). Methods: A partial image of the anterior region of the maxilla was obtained by computed tomography. Three models of finite element were made using 3D modeling software (SolidWorks): Ti-Ti (control): implant morse cone (3.75 x 11mm; NobelActive) and titanium abutment (Esthetic Abutment); Ti-Zr: cone morse implant in titanium (3.75 x 11mm; NobelActive) and zirconia abutment (Procera Esthetic Abutment #9); Zr: monotype zirconia implant (4.1 x 12mm; Straumann Pure Ceramic). Computerized crowns of element 11 in lithium disilicate (IPS e.max Press, Ivoclar Vivadent) cemented in all groups were created. A load of 100N (45º) was applied simulating the excursion movement of the incisal guide. The von Mises, modified von Mises, maximum (tensile) and minimum (compression) principal stresses were obtained, compared and used for the quantitative and qualitative evaluation of the groups. Results: The Zr presented the lowest values of maximum, minimum, and von Mises tensions than the two pieces systems (Ti-Ti and Ti-Zr). Ti-Zr group had the highest values of tensions evaluated in this study. Conclusions: The type of material as well as the geometry of implant influenced the tension values evaluated.

Objectives The aim of this study was to evaluate the influence of ferule and the post type on the fracture strength and stress distribution in premolars. Materials and Methods Forty human mandibular premolars were decoronated, allocated in four groups, and restored as follows: CPC-NF: cast post-and-core and absence of ferule; CPC-F: cast post-and-core and presence of ferule; FPC-NF: glass-fiber posts and absence of ferule; FPC-F: glass-fiber posts and presence of ferule. The fracture strength (FS) and failure patterns were evaluated. Finite element analysis (FEA) evaluated the stress distribution. Results FS did not differ between CPCs and FPC either in presence or in absence of ferule. The presence of ferule increased FS with both post types. Mean values of FS for ferule groups were higher than functional or parafunctional loads reported in literature, which was not the case for FPC-NF when compared to parafunctional loads. FEA with a functional load showed slightly higher compressive stresses in dentin in the group CPC-NF, which was much lower than the compressive strength of dentin. Lower percentage of catastrophic failures was observed in nonferule groups irrespective of post type, which was explained by the stress concentration in the cervical root region when FEA with the FS load was simulated. Conclusion Ferule effect was shown to be more important than post type in the analysis. Both posts showed potential to withstand functional loads irrespective of presence of ferule. However, the mean FS was lower than parafunctional loads for FPC in the absence of ferule.