[EO-9] Principal Strains in the Bone around an Implant Supporting a Restoration Fabricated Using a Fully Digital Workflow: a 3D Finite Element Analysis
[Abstract]
[Objective]
This study is part of a project that investigates the relation between bone strain and implant overload1). It aims to analyze bone strains around an implant under occlusal loads in a 3D finite element method (FEM) model constructed from a helical CT of a patient who received the implant treatment under a fully digital workflow.
[Method]
For the 3D FEM model, the helical CT of a partially edentulous patient before implant insertion in the second molar region of the mandible was used, to minimize artifacts. An optical scanner (Primescan, Dentsply) was used to obtain STL-data of an implant of the same type with that subsequently placed in the patient and those of the superstructure before its set. These were superimposed over the CT data, while using intraoral scan data of the superstructure and neighboring teeth, as guides for their positioning. Loads were defined based on the maximum bite forces at each occlusal contact area, totaling 82.3 N as measured by pressure-sensitive sheets. For modeling and analysis, RATOC programs for bone morphometry (TRI/3D-BON), superimposition (TRI/3D-ADJ), and 3D-FEM analysis (TRI/3D-FEM64) were used.
This study was approved by the Ethics Committee of Niigata University and informed consent was obtained from the patient.
[Results and Discussion]
The highest tensile principal strain was located in the trabecular bone buccally from the apical region of the implant. High tensile strains were distributed over large areas in the bone surrounding the implant. The highest compressive principal strain was located in the cortical bone bucco-mesially from the implant neck. High compressive strains tended to concentrate in the cortical bone around the implant neck and trabecular bone below the implant.
This is the first 3D FEA attempting to model the trabecular bone around an implant from helical CT data. Because of the low CT resolution, the trabecular structure was modelled as a first approximation and requires further validation.
[References]
1) Stegaroiu R, Kurokawa K, Arai Y, et al. Analysis of Principal Strains in Peri-implant Bone Under Occlusal Loads. The 71st Annual Meeting of the Japanese Association for Dental Research Program and Abstracts of Papers 2023;92.
[Objective]
This study is part of a project that investigates the relation between bone strain and implant overload1). It aims to analyze bone strains around an implant under occlusal loads in a 3D finite element method (FEM) model constructed from a helical CT of a patient who received the implant treatment under a fully digital workflow.
[Method]
For the 3D FEM model, the helical CT of a partially edentulous patient before implant insertion in the second molar region of the mandible was used, to minimize artifacts. An optical scanner (Primescan, Dentsply) was used to obtain STL-data of an implant of the same type with that subsequently placed in the patient and those of the superstructure before its set. These were superimposed over the CT data, while using intraoral scan data of the superstructure and neighboring teeth, as guides for their positioning. Loads were defined based on the maximum bite forces at each occlusal contact area, totaling 82.3 N as measured by pressure-sensitive sheets. For modeling and analysis, RATOC programs for bone morphometry (TRI/3D-BON), superimposition (TRI/3D-ADJ), and 3D-FEM analysis (TRI/3D-FEM64) were used.
This study was approved by the Ethics Committee of Niigata University and informed consent was obtained from the patient.
[Results and Discussion]
The highest tensile principal strain was located in the trabecular bone buccally from the apical region of the implant. High tensile strains were distributed over large areas in the bone surrounding the implant. The highest compressive principal strain was located in the cortical bone bucco-mesially from the implant neck. High compressive strains tended to concentrate in the cortical bone around the implant neck and trabecular bone below the implant.
This is the first 3D FEA attempting to model the trabecular bone around an implant from helical CT data. Because of the low CT resolution, the trabecular structure was modelled as a first approximation and requires further validation.
[References]
1) Stegaroiu R, Kurokawa K, Arai Y, et al. Analysis of Principal Strains in Peri-implant Bone Under Occlusal Loads. The 71st Annual Meeting of the Japanese Association for Dental Research Program and Abstracts of Papers 2023;92.