Design of a patient-specific mandible reconstruction implant with dental prosthesis for metal 3D printing using integrated weighted topology optimization and finite element analysis

Integrating Finite Element Death Technique and Bone Remodeling Theory to Predict Screw Loosening Affected by Radiation Treatment after Mandibular Reconstruction Surgery

“…Cortical, cancellous bones and reconstruction implant/screws were assumed with linear elastic and isotropic properties. Elastic modulus and Poisson’s ratio material property values were adopted from the relevant literature [ 1 ] ( Table 1 ). Nodes on the condyle were constrained in all directions to prevent movement as the boundary conditions and a concentrated oblique occlusal load with 90N was applied to the incisor as the load condition ( Figure 1 B) [ 18 , 19 ].…”

“…This study combined bone remodeling theory and finite element death technology to simulate bone necrosis behavior around the fixation screw from radiation treatment after surgery [ 1 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. The accumulation of osteonecrosis in the elements around the fixation screw at different time points can be simulated using different iterative simulation times (denoted as IT_X; X was the number of iterations) [ 22 ].…”

“…The fibula free flap is the gold standard surgery for the vascularized graft used to reconstruct severe defects in the mandible because of its versatility, predictability, and favorable fibula bone quantity for dental implants to facilitate prosthetic rehabilitation [ 1 , 2 , 3 , 4 ]. The reconstruction plate and fixation screws were used to secure the bone graft in the lower mandible border to bridge the mandibular stumps to bear the occlusal load to maintain fixation stability during the bone healing phase [ 1 , 5 , 6 , 7 , 8 ]. However, hidden worries and the risk of fixation screw loosening still exist after surgery.…”

“…Enhanced understanding of the formative bone response to loads (modeling) and maintenance for an integrated state (remodeling) could improve the clinical treatment. Bone resorption surrounding the fixation screw is a major problem as it causes looseness at the bone–screw interface, thus undermining the implant system integrity [ 1 , 8 , 17 ]. When radiotherapy is performed after the operation, the bone surrounding the fixation screw is more likely to be damaged when receiving a low mechanical load due to the bone remodeling ability becoming out of balance.…”

A Numerical Study of Fluid Flow in the Porous Structure of Biological Scaffolds

“…On the other hand, the use of 3D printing tech-nology in TE will not only solve the existing difficulties, but also may lead to significant progress in the field of regenerative medicine, due to some reasons such as the simplicity of 3D printing technology; the ability to create objects with a unique individual geometric shape; precision manufacturing of parts; the possibility of using various types of materials [8][9][10]. Today, the use of 3D printing in the field of medicine has a general name -bioprinting and includes the manufacture of implants [11] and biological scaffolds for growing organs and tissues [12], testing drugs [13], as well as direct printing of organs [14]. Unlike traditional methods used in 3D printing technology, materials in bioprinting are mainly presented by cells, biological materials and nutrients that stimulate cell growth.…”