Abstract: Objective Based on finite element analysis, the stress and displacement distributions of the titanium mesh were analyzed under different thicknesses, different porosities and different rod diameter of the fillings of the convention unit cell structure in response to vertical external forces. The results of the analysis can provide a biomechanical basis for the design of personalized titanium mesh when used to guide bone regeneration in the treatment of jawbone defects. Methods The mandible of a patient with 31-32 defects was used as a study carrier for small-sized titanium mesh (S-type), and the mandible of a patient with 33-37 defects was used for large-sized titanium mesh (L-type). A 3D model reconstruction of the jaws was performed for their CBCT images, respectively. Based on this, titanium mesh with different thicknesses, porosities, and rod diameters was designed, and 3D finite element models were established. The stress and displacement distribution of the titanium mesh under stress conditions was analyzed by FEM analysis. Results With an increase in titanium mesh thickness, the stresses and displacements of titanium mesh show a decreasing trend; with an increase in the porosity of titanium mesh, the stresses and displacement of titanium mesh show an increasing trend; with an increase in the diameter of the titanium mesh rod, the stress and displacement of S-type titanium mesh showed a decreasing trend, while the stress and displacement of L-type titanium mesh showed no obvious trend. Conclusion The stress values of all titanium meshes are within the safe equivalent stress range with sufficient strength for thicknesses of 0.4 mm and above, considering that too thick titanium mesh will stimulate the mucosa, 0.4mm thickness titanium mesh is more suitable for clinical needs; stress values were within the safe equivalent force range for S-type with 55% porosity and below, and L-type with 55%~68% porosity, with sufficient strength, increasing the porosity of titanium mesh can provide more adequate blood channels to the mucosa, reducing the risk of mucosal ischemia atrophy and cracking, L-type titanium mesh should try to choose 68% porosity, S-type titanium mesh should choose 55% porosity; S-type titanium mesh rod diameter at 0.7 mm and above, L-type titanium mesh rod diameter at 0.5 mm and above, can meet the strength requirements , comprehensive porosity and other comprehensive factors, considering that the larger the rod diameter, the mucosal stimulation increases, so the 0.7 mm rod diameter titanium mesh is more suitable for clinical needs.

Key words: Guided bone regeneration, Titanium mesh, Finite element analysis, Convention unit cell structure