Semi-automatic generation of finite element meshes of dental preparations

The mechanical properties and elastic behaviour of periodontal tissue are a decisive factor in understanding initial tooth mobility and bone remodelli ng processes in orthodontics. An experimental set-up was designed to precis ely determine a tooth's elastic response to different loading conditions. S egments of pig's maxilla bearing separated molars were used, and their mech anical response to loading was recorded. Subsequently, finite element analy sis (FEA) was performed on the basis of the experimental data. The combinat ion of experimental and numerical methods was used to determine the materia l properties of the periodontal ligament (PDL). The geometries of the prepa rations were reconstructed and FE meshes generated semi-automatically with the aid of the special computer program, CAGOG (Computer Aided Generator fo r Orthodontic Geometries) to optimally match the experimental geometry. Non linear material parameters were determined for the PDL and verified by comp aring experimental and numerical results obtained in other specimens with a n error of about 10%. This good correlation indicates that the selected met hod of mesh generation is appropriate for creating realistic FE models that can be compared with experimental results.