Objective: Aim of study was to develop two finite element models of one-piece implants of different materials and to compare stress distribution in surrounding bone as a result of application of an extra-axial force. Methods: WhiteSky one-piece implant design (Bredent GmbH&Co.KG,Senden,Germany) was used to realise two identical 3D geometrical models. Implant length and diameter were 20.8mm and 4.1mm, respectively. The crown was derived from average dimensions of maxillary central incisor. Each model contained one-piece titanium or zirconia implant with Y-PSZ zirconia crown, inserted into generic bone region having both cortical and trabecular portions. All materials were considered linearly elastic, and their properties were obtained from literature (Table). The only difference between two models was in implant material. Once meshed, each model incorporated 134512 nodes and 91395 elements. A 45-degree 100N force was applied to palatal surface of crown to mimic occlusal force. Stress and strain analysis was performed on implant, cortical bone and trabecular bone. The software used for analysis was Ansys 10.0 (Ansys Inc.,Cononsburg,PA,USA). Results: By comparing the two models some considerations can be derived. For both zirconia and titanium models, stress distribution (σx, σeq) in implant and cortical bone was comparable and localized at cervical level, with zirconia showing slightly less stress than titanium (Figg. 1,2). Otherwise, in trabecular bone zirconia implant caused slightly higher levels of stress that were localized at apical level, probably due to higher stiffness of material. Conclusion: From the finite element analysis that was performed no substantial difference emerged in stress distribution between one-piece titanium and zirconia implants, therefore, they can be considered comparable from a mechanical point of view.
Stress distribution around one-piece implants: a finite element study
MOBILIO, Nicola;STEFANONI, Filippo;MOLLICA, Francesco;CATAPANO, Santo
2010
Abstract
Objective: Aim of study was to develop two finite element models of one-piece implants of different materials and to compare stress distribution in surrounding bone as a result of application of an extra-axial force. Methods: WhiteSky one-piece implant design (Bredent GmbH&Co.KG,Senden,Germany) was used to realise two identical 3D geometrical models. Implant length and diameter were 20.8mm and 4.1mm, respectively. The crown was derived from average dimensions of maxillary central incisor. Each model contained one-piece titanium or zirconia implant with Y-PSZ zirconia crown, inserted into generic bone region having both cortical and trabecular portions. All materials were considered linearly elastic, and their properties were obtained from literature (Table). The only difference between two models was in implant material. Once meshed, each model incorporated 134512 nodes and 91395 elements. A 45-degree 100N force was applied to palatal surface of crown to mimic occlusal force. Stress and strain analysis was performed on implant, cortical bone and trabecular bone. The software used for analysis was Ansys 10.0 (Ansys Inc.,Cononsburg,PA,USA). Results: By comparing the two models some considerations can be derived. For both zirconia and titanium models, stress distribution (σx, σeq) in implant and cortical bone was comparable and localized at cervical level, with zirconia showing slightly less stress than titanium (Figg. 1,2). Otherwise, in trabecular bone zirconia implant caused slightly higher levels of stress that were localized at apical level, probably due to higher stiffness of material. Conclusion: From the finite element analysis that was performed no substantial difference emerged in stress distribution between one-piece titanium and zirconia implants, therefore, they can be considered comparable from a mechanical point of view.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
