Biomeechanical Characterization Of 3D-Printed Individualized Ti-mesh(Membrane) For Alveolar Bone Defects

Objective: The purpose of this study was to design an individualized titanium mesh and to explore the effect of titanium mesh with different thicknesses and pore sizes on its mechanical properties.We also investigated the biomechanical characteristics of subperiosteal implant based on the histological observation.Methods: In the present study,we have designed and manufactured a customized titanium mesh based on computerized tomography(CT)of individual patients.The designed titanium mesh with different diameters and thicknesses were explored based on their mechanical strength through a three-point bending test and FEA analysis.Otherwise,three beagle dogs received customized titanium mesh.During the postoperative healing period,the animals were inspected regularly.All complications were recorded.At 12 weeks following the implant insertion procedure,all animals were sacrificed.Micro-CT and histology analysis were used to evaluate whether or not there was bony osseointegration of the titanium mesh.Results: According to this study,the mechanical properties of titanium mesh increased when the thickness decreased(0.5 mm to 0.3 mm).With an increase in mesh diameter(3 mm to 5 mm),the mechanical properties of mesh decreased.The diameter of titanium mesh has less influence on its mechanical properties than does the thickness of the mesh.Titanium mesh with a thickness of 0.4 mm is strong enough and causes less stimulation to mucosa;therefore,it is more suitable for clinical use.In addition,parameters of titanium mesh should be decided clinically according to bone defect size,defect location and force situation.The animal study showed that all of the titanium mesh healed uneventfully and without mesh exposure.The Micro-CT images 12 weeks after surgery showed that the personalized titanium mesh framework could be well fitted to the jaw bone of beagle dogs and without obvious bone resorption.Bone tissue images with slightly increased density between the titanium mesh and the bone surface could be seen in the bone defect area,and artificial bone material could be seen without absorption.Histological examination confirmed that new bone formation was observed between the titanium mesh and the bone surfaceConclusion:The stiffness of Ti-mesh can maintain space better than other membrane and is conducive to the shaping of bone grafting materials,but may result in mucosal irritation that leads to exposure of the membrane.The custom-made titanium mesh offer greater advantages over commercial meshes by shortening the duration of surgery and eliminating the risk of postoperative infections.Within the limitations of this research regarding the optimal thickness of the titanium mesh,the results indicate that the titanium mesh with a thickness of 0.4 mm is more suitable for clinical use.Regarding the optimal pore size of the titanium mesh,the diameter of titanium mesh had less influence on its mechanical properties.Animal experiments show that personalized titanium mesh is reliable for alveolar bone augmentation,with low postoperative exposure rate.