A 3-D finite element study of the influence of crown-implant ratio on stress distribution.
The purpose of this study was to assess the influence of the crown height of external hexagon implants on the displacement and distribution of stress to the implant/bone system, using the three-dimensional finite element method. The InVesalius and Rhinoceros 4.0 softwares were used to generate the bone model by computed tomography. Each model was composed of a bone block with one implant (3.75 x 10.0 mm) with external hexagon connections and crowns with 10 mm, 12.5 mm and 15 mm in height. A 200 N axial and a 100 N oblique (45°) load were applied. The models were solved by the NeiNastran 9.0 and Femap 10.0 softwares to obtain the results that were visualized by maps of displacement, von Mises stress (crown/implant) and maximum principal stress (bone). The crown height under axial load did not influence the stress displacement and concentration, while the oblique loading increased these factors. The highest stress was observed in the neck of the implant screw on the side opposite to the loading. This stress was also transferred to the crown/platform/bone interface. The results of this study suggest that the increase in crown height enhanced stress concentration at the implant/bone tissue and increased displacement in the bone tissue, mainly under oblique loading.
Discipline of Complete Denture, School of Dentistry of Pernambuco, UPE - University of Pernambuco, RecifePE, Brazil.
Sandra Lúcia Dantas
SL
de Moraes
Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, UNESP - Univ Estadual Paulista, AraçatubaSP, Brazil.
Fellippo Ramos
FR
Verri
Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, UNESP - Univ Estadual Paulista, AraçatubaSP, Brazil.
Joel Ferreira
JF
Santiago
Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, UNESP - Univ Estadual Paulista, AraçatubaSP, Brazil.
Daniel Augusto de Faria
DA
Almeida
Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, UNESP - Univ Estadual Paulista, AraçatubaSP, Brazil.
Caroline Cantieri
CC
de Mello
Department of Dental Materials and Prosthodontics, Araçatuba School of Dentistry, UNESP - Univ Estadual Paulista, AraçatubaSP, Brazil.
Eduardo Piza
EP
Pellizzer
D001696:Biomechanical Phenomena; D003442:Crowns; D003722:Dental Alloys; D015921:Dental Implants; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention / Q000295:instrumentation*; D019094:Dental Prosthesis, Implant-Supported; D003799:Dental Stress Analysis / Q000379:methods*; D020342:Finite Element Analysis; D003765:Models, Dental; D012984:Software; D014057:Tomography, X-Ray Computed
D003722:Dental Alloys; D015921:Dental Implants