Ghazaleh Moradkhani; Morad Karimpour; S Mahmoud Taheri
Abstract
Background: Porous titanium structures have recently gained considerable popularity among researchers in studies examining bone ingrowth and osseointegration. Porous implants fabricated using triply periodic minimal surface design (TPMS) and designed through 3D printing techniques exhibited remarkable ...
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Background: Porous titanium structures have recently gained considerable popularity among researchers in studies examining bone ingrowth and osseointegration. Porous implants fabricated using triply periodic minimal surface design (TPMS) and designed through 3D printing techniques exhibited remarkable mechanical strength and cell viability compared to conventional implants. This study aimed to evaluate the effect of pore size of titanium implants with gyroid structure.Methods: This study was conducted on Adult male Wistar rats weighing 350 and 450 g for the animal study by the calvarial defect model to investigate bone regeneration. Three disk-shaped implants were designed using a gyroid structure with pore sizes of 400, 500, and 600 micrometers. All implants were made by additive manufacturing (Selective Laser Melting) using Ti6Al4V medical-grade powder. Animals were sacrificed after 12 weeks, the skin was removed from the calvaria, and the implants were removed for histological examination.Results: Gyroid structures had a high surface-to-volume ratio and pore connectivity, facilitating cell adhesion and ossification. A significant amount of bone ingrowth was observed in the 400 mm group, so that bone penetrated into pores significantly more than in the other groups. However, the vascularization was more pronounced in the 600 μm group than in the other groups.Conclusion: According to the results, there was a positive effect of porosity in titanium implants in encouraging bone ingrowth. The porosity size of 400 μm was more suitable for the differentiation and proliferation of bone cells and thus the osseointegration in porous titanium implants with gyroid structure.
Spine
Seyyed Mohammad Moein Fatemi; Mohammad Nikkhoo; Mostafa Rostami; Chih-Hsiu Cheng
Abstract
In recent years, spinal fusion surgery has become one of the most common treatments for spinal cord injuries, while the interbody cages, which replace the damaged interbody discs in the surgeries, have undergone extensive changes in design and material. These changes are quite visible, ranging from plain ...
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In recent years, spinal fusion surgery has become one of the most common treatments for spinal cord injuries, while the interbody cages, which replace the damaged interbody discs in the surgeries, have undergone extensive changes in design and material. These changes are quite visible, ranging from plain titanium cages made using the conventional manufacturing methods to customized porous titanium cages, which are made using additive manufacturing technology, or titanium-coated polymer cages. Among all the materials used in manufacturing the interbody cages, PolyEther Ether Ketone (PEEK) and titanium are the most common ones. Each of these two has its own advantages and disadvantages. Several studies have compared these two materials, mostly based on the two characteristics of subsidence and fusion rates. The present study performed a comprehensive review of the published clinical studies comparing the titanium and PEEK cages in order to make a comprehensive evaluation of these two. According to the reviewed studies, both materials had relatively similar results in subsidence rate, with no significant difference. However, it was shown that the titanium cages had a better fusion rate and subsequently were more likely to be successful in the clinical settings than the PEEK cages.
