Comparative finite element analysis of stress distribution of different implant- supported crown and abutment materials / Chan Wan Wan

Chan , Wan Wan (2024) Comparative finite element analysis of stress distribution of different implant- supported crown and abutment materials / Chan Wan Wan. Masters thesis, Universiti Malaya.

	PDF (The Candidate's Agreement) Restricted to Repository staff only Download (243Kb)
	PDF (Thesis M.A.) Download (2359Kb)

Abstract

This study aimed to evaluate the stress distribution of three-dimensional (3D) printed ceramic filled hybrid materials and zirconia as abutments and implant-supported crowns using a finite element study model. Five groups of materials were: computer-aided design and computer-aided manufacturing (CAD/CAM) zirconia implant-supported crown with CAD/CAM zirconia custom abutment (ZR-ZR); 3D printed VarseoSmile® Crown Plus implant-supported crown with CAD/CAM zirconia custom abutment (VSC-ZR); CAD/CAM zirconia implant-supported crown with 3D printed VarseoSmile® Crown Plus custom abutment (ZR-VSC); 3D printed VarseoSmile® TriniQ® implant-supported crown with CAD/CAM zirconia custom abutment (VST-ZR); and CAD/CAM zirconia implant-supported crown with 3D printed VarseoSmile® TriniQ® (ZR-VST) custom abutment. The implant-supported crown of a mandibular first molar was designed and modelled in computer-aided design (CAD) software, and analysed using finite element analysis (FEA) ANSYS Workbench 2021 R1 software. All the materials were considered homogenous, isotropic, and linearly elastic. A 600N vertical load (Load Case 1) was applied to the central axis of implant onto the crown, while a 225N oblique load (Load Case 2) was applied 45° to the central axis of implant onto the crown. The von Mises stress was recorded at crown, cement between crown and CAD/CAM custom abutment, CAD/CAM custom abutment, cement between CAD/CAM custom abutment and titanium base (Ti-base) abutment, abutment screw, titanium base abutment, fixture, cortical, and cancellous bone. The von Mises stress percentage difference was compared to the control group ZR-ZR. The stress concentration areas were indicated by colorimetric map. At the crown, Group ZR-VST had the highest von Mises stress (214.39 MPa; 112.72 MPa), while Group VST-ZR had the lowest (173.66 MPa; 101.58 MPa) in Load Case 1 and 2, respectively. The stress concentration areas were the crown's occlusal area, the cement layer of the neck and top region of the abutment, top region of titanium base abutment, the internal connection to the abutment screw, the collar area at gingival level, first thread of abutment screw, and cervical area of titanium base abutment. At the CAD/CAM custom abutments, Groups ZR-VSC and ZR-VST demonstrated the lowest stress in Load Case 1 and 2, which were 46.66 MPa and 44.62 MPa; 45.34 MPa and 41.95 MPa, respectively. The cement between the crown and the CAD/CAM custom abutment showed the lowest stress in Group ZR-VSC (28.19 MPa) and Group ZR-VST (28.92 MPa) in Load Case 1. In Load Case 1, the cement between the CAD/CAM custom abutment and the Ti-base abutment demonstrated the greatest stress in Groups ZR-VSC (70.14 MPa) and ZR-VST (72.52 MPa), similarly observed in Load Case 2 (Group ZR-VSC:54.72 MPa; Group ZR-VST: 57.76 MPa). The stress at the fixture in the cortical and cancellous bones was comparable across all groups under both loads. In conclusion, the combination of implant-supported crown and abutment with different moduli of elasticity positively influences stress distribution at the crown, cement between crown and CAD/CAM custom abutment, CAD/CAM custom abutment, abutment screw, cement between CAD/CAM custom abutment and Ti-base abutment, Ti-base abutment and fixture, but no effect on stress distribution in the peri-implant bone structure.

Actions (For repository staff only : Login required)