Complete Osseointegration of a Retrieved 3-D Printed Porous Titanium Cervical Cage

Introduction: Porous 3D-printed titanium has only recently been introduced for spinal applications. Evidence around its use is currently limited to animal studies and only few human case series. This study describes the histological findings of a retrieved EIT cervical cage, explanted 2 years after insertion.Materials and Methods: The patient underwent a double level C4/C5 & C5/C6 anterior cervical decompression using EIT cervical cages without an anterior plate. Two years later the C6/7 level degenerated and began to cause myelopathic symptoms. In order to address the kyphotic imbalance of the cervical spine and fix the C6/7 level, the surgeon decided to remove the C5/6 cervical cage and bridge the fusion from C4 to C7 inclusive. The retrieved cage was histologically evaluated for bone ingrowth and signs of inflammation.Results: MRI demonstrated spinal canal stenosis at C6/C7. Plain radiographs confirmed well-integrated cervical cages at 2 years postoperative. The peroperative surgical need to use a chisel to remove the implant at C5/C6 reconfirmed the solid fusion of the segment. Macroscopically white tissue, indicative of bone, was present at both superior and inferior surfaces of the explanted specimen. Histological evaluation revealed complete osseointegration of the 5 mm high EIT Cellular Titanium® cervical cage, displaying mature lamellar bone in combination with bone marrow throughout the cage. Furthermore, a pattern of trabecular bone apposition (without fibrous tissue interface) and physiological remodeling activity was observed directly on the cellular titanium scaffold.Conclusion: This histological retrieval study of a radiologically fused cervical EIT cage clearly demonstrates complete osseointegration within a 2-year time frame. The scaffold exhibits a bone in growth pattern and maturation of bone tissue similar of what has been demonstrated in animal studies evaluating similar porous titanium implants. The complete osseointegration throughout the cage indicates physiological loading conditions even in the central part of the cage. This pattern suggests the absence, or at least the minimization, of stress-shielding in this type of porous titanium cage.

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Bone Ingrowth Into Porous Bioactive Titanium Implant for Load-Bearing Use: Experimental Study Using a Novel Canine Anterior Interbody Fusion Model

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.330-332.987 ◽

2007 ◽

Vol 330-332 ◽

pp. 987-990

Author(s):

Mitsuru Takemoto ◽

Shunsuke Fujibayashi ◽

Masashi Neo ◽

Kazutaka So ◽

Norihiro Akiyama ◽

...

Keyword(s):

Interbody Fusion ◽

Bone Ingrowth ◽

Average Pore Size ◽

Fibrous Tissue ◽

Titanium Implant ◽

Porous Titanium ◽

Histological Evaluation ◽

Biological Fixation ◽

Load Bearing ◽

Porous Titania

We have developed a porous titanium implant sintered with spacer particles (porosity = 50 %, average pore size ± standard deviation = 303 ± 152 !m, yield compression strength = 100MPa). This porous titanium was successfully treated with chemical and thermal treatment that gives a bioactive micro-porous titania layer on the titanium surface, and it is expected as effective biomaterial for biological fixation on load bearing condition. In this study, ten adult female beagle dogs underwent anterior lumbar interbody fusion at L6-7 using either BT-implant or non-treated implant (NT-implant), then followed by posterior interspinous wiring and facet screw fixation. The radiographic evaluations were performed 1, 2 and 3 months postoperatively using X-ray fluoroscopy. Animals were sacrificed after 3 months postoperatively, and fusion status was evaluated by manual palpation. Histological evaluation was also performed. Both histological and radiological evaluation revealed that interbody fusion was achieved in 5 of 5 dogs (100%) in BT-group and 3 of 5 dogs (60%) in NT-group. In BT implants, we could observe a large amount of new bone formation from periphery to the center of the implant, whereas in NT implants, fibrous tissue formation was still observed even in the implants with successful fusion. The results of this study indicate that porous bioactive titanium implant will represent a new osteoconductive biomaterial with improved fusion characteristics.

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Highly Porous Titanium Cups versus Hydroxyapatite-Coated Sockets: Midterm Results in Metachronous Bilateral Total Hip Arthroplasty

Medical Principles and Practice ◽

10.1159/000500876 ◽

2019 ◽

Vol 28 (6) ◽

pp. 559-565 ◽

Cited By ~ 1

Author(s):

Francesco Castagnini ◽

Barbara Bordini ◽

Makiko Yorifuji ◽

Federico Giardina ◽

Simone Natali ◽

...

Keyword(s):

Electron Beam ◽

Electron Beam Melting ◽

Intraoperative Complications ◽

Case Series ◽

Stress Shielding ◽

Porous Titanium ◽

Total Hip ◽

Radiographic Parameters ◽

The Mean ◽

Highly Porous

Objective: Highly porous titanium cups have been recently introduced, with contradictory outcomes. A retrospective consecutive case series involving bilateral metachronous total hip arthroplasties (THA) performed with 2 different cups, i.e., Fixa (F) and Fixa Ti-Por (T) (Adler Ortho, Milan, Italy), and the same stem, was evaluated. T sockets, manufactured using electron beam melting, were supposed to prove superior in terms of clinical results, survival rates, and radiographic parameters in comparison to hydroxyapatite-coated F cups with conventional porosity. Subjects and Methods: Twenty-four bilateral metachronous THAs with an F cup on one side and a T socket on the other side were evaluated. Preoperative and postoperative Harris hip scores (HHS) were collected for every patient. Radiographic signs of loosening were assessed. The radiographic signs of osseointegration (radiolucent lines, superolateral buttress, inferomedial buttress, radial trabeculae, and stress shielding) were evaluated. Results: No intraoperative complications occurred. The mean HHS score was excellent and comparable in both groups. At the mean follow-up of 134 months (F) and 79 months (T), no cup or liner revisions were performed. No radiographic signs of loosening were reported. All of the patients revealed 3 parameters of good bony ingrowth at least. Both groups showed similar radiographic parameters regarding osseointegration, which were stable over the time. Stress shielding was more evident in the T cohort (p =0.07). Conclusion: Highly porous titanium cups produced using an additive manufacturing and electron beam melting technology achieved reliable midterm clinical and radiographic results not inferior to those of second-generation cups.

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Novel Micro-CT Based 3-Dimentional Structural Analyses of Porous Biomaterials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.330-332.967 ◽

2007 ◽

Vol 330-332 ◽

pp. 967-970 ◽

Cited By ~ 2

Author(s):

B. Otsuki ◽

Mitsuru Takemoto ◽

Shunsuke Fujibayashi ◽

Masashi Neo ◽

Tadashi Kokubo ◽

...

Keyword(s):

Network Structure ◽

Bone Ingrowth ◽

Average Pore Size ◽

Three Dimensional ◽

Porous Titanium ◽

Titanium Implants ◽

Average Pore ◽

Tissue Ingrowth ◽

Porous Biomaterials

A porous structure comprises pores and pore throats with a complex three-dimensional network structure, and many investigators have described the relationship between average pore size and the amount of bone ingrowth. However, the influence of network structure or pore throats for tissue ingrowth has rarely been discussed. Bioactive porous titanium implants with 48% porosity were analyzed using specific algorithms for three-dimensional analysis of interconnectivity based on a micro focus X-ray computed tomography system. In vivo histological analysis was performed using the very same implants implanted into the femoral condyles of male rabbits for 6 weeks. This matching study revealed that more poorly differentiated pores tended to have narrow pore throats, especially in their shorter routes to the outside. Data obtained suggest that this sort of novel analysis is useful for evaluating bone and tissue ingrowth into porous biomaterials.

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Improved Corrosion Behavior and Biocompatibility of Porous Titanium Samples Coated with Bioactive Chitosan-Based Nanocomposites

Materials ◽

10.3390/ma14216322 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6322

Author(s):

Cristina García-Cabezón ◽

Vanda Godinho ◽

Coral Salvo-Comino ◽

Yadir Torres ◽

Fernando Martín-Pedrosa

Keyword(s):

Corrosion Resistance ◽

Stress Shielding ◽

Porous Titanium ◽

Substrate Material ◽

Titanium Implants ◽

Potential Candidate ◽

Protection Efficiency ◽

Cellular Behavior ◽

One Step ◽

Current Densities

Porous titanium implants can be a good solution to solve the stress shielding phenomenon. However, the presence of pores compromises mechanical and corrosion resistance. In this work, porous titanium samples obtained using a space-holder technique are coated with Chitosan, Chitosan/AgNPs and Chitosan/Hydroxyapatite using only one step and an economic electrodeposition method. The coatings’ topography, homogeneity and chemical composition were analyzed. A study of the effect of the porosity and type of coating on corrosion resistance and cellular behavior was carried out. The electrochemical studies reveal that porous samples show high current densities and an unstable oxide film; therefore, there is a need for surface treatments to improve corrosion resistance. The Chitosan coatings provide a significant improvement in the corrosion resistance, but the Chitosan/AgNPs and Chitosan/HA coatings showed the highest protection efficiency, especially for the more porous samples. Furthermore, these coatings have better adherence than the chitosan coatings, and the higher surface roughness obtained favors cell adhesion and proliferation. Finally, a combination of coating and porous substrate material with the best biomechanical balance and biofunctional behavior is proposed as a potential candidate for the replacement of small, damaged bone tissues.

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Fabrication of bioactive 3D printed porous titanium implants with Sr ion-incorporated zeolite coatings for bone ingrowth

Journal of Materials Chemistry B ◽

10.1039/c8tb00328a ◽

2018 ◽

Vol 6 (20) ◽

pp. 3254-3261 ◽

Cited By ~ 16

Author(s):

Shuang Wang ◽

Ruiyan Li ◽

Dongdong Li ◽

Zhi-Yong Zhang ◽

Guancong Liu ◽

...

Keyword(s):

Bone Ingrowth ◽

Porous Titanium ◽

Titanium Implants ◽

3D Printed ◽

Strontium Ion ◽

Zeolite Coatings

Strontium ion incorporated zeolites are uniformly fabricated on a 3D printed porous titanium scaffold for bone ingrowth.

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BONE AND SOFT TISSUES INTEGRATION IN POROUS TITANIUM IMPLANTS (EXPERIMENTAL RESEARCH)

Traumatology and Orthopedics of Russia ◽

10.21823/2311-2905-2018-24-2-95-107 ◽

2018 ◽

Vol 24 (2) ◽

pp. 95-107 ◽

Cited By ~ 1

Author(s):

R. M. Tikhilov ◽

I. I. Shubnyakov ◽

A. O. Denisov ◽

V. A. Konev ◽

I. V. Gofman ◽

...

Keyword(s):

Bone Tissue ◽

Latissimus Dorsi ◽

Fibrous Tissue ◽

Porous Titanium ◽

Additive Technologies ◽

Titanium Implants ◽

Knee Joints ◽

Control Group ◽

Muscular Tissue ◽

Tissue Integration

Aim. It’s common that revision arthroplasty of the large joints demands replacing of bone defects of irregular geometrical shapes and simultaneous restoring of support ability and ability to integrate surrounding muscular and tendinous structures into an implant that is required for a complete restoration of joint function.The purpose.To experimentally study the process of integration for muscular and bone tissue as well as tendinous and ligamentous structures into porous titanium materials.Material and methods. During in vivo experiment the authors created a standardized bone defect in 6 rabbits of chinchilla breed at the point of patella ligament attachment as well as a delamination area of muscular tissue in latissimus dorsi. Both knee joints and both latissimus dorsi were used in each animal. Study group included titanium implants with three-dimensional mesh structure. Control group — solid titanium implants with standard porosity. Titanium implants were produced by additive technologies with preliminary prototyping. The porosity corresponded to trabecular metal, striations — 0.45, pores size —100–200 microns. Study and control components were implanted in the identical conditions into the corresponding anatomical sites. Postoperative AP and lateral roentgenograms of knee joints were performed for all animals. Morphological research was conducted on day 60 after the implantation and strength properties were studied at day 90 after the implantation.Results.The authors observed bony ingrowth into implant pores with minimal volume of fibrous tissue, a distinct connective integration was reported represented by a dense fibrous tissue in the pores of components implanted into the muscular tissue. Testing of fixation strength of the study implants demonstrated a clearly superior strength of soft and bone tissue integration into the experimental mesh implants produced using additive technologies.

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Cartilage and Bone Ingrowth into Porous Titanium Implants

Titanium Alloys in Surgical Implants ◽

10.1520/stp28948s ◽

2009 ◽

pp. 255-255-10

Author(s):

DD Nelson ◽

HE Rubash ◽

DC Mears

Keyword(s):

Bone Ingrowth ◽

Porous Titanium ◽

Titanium Implants

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A porous bioactive titanium implant for spinal interbody fusion: an experimental study using a canine model

Journal of Neurosurgery Spine ◽

10.3171/spi-07/10/435 ◽

2007 ◽

Vol 7 (4) ◽

pp. 435-443 ◽

Cited By ~ 44

Author(s):

Mitsuru Takemoto ◽

Shunsuke Fujibayashi ◽

Masashi Neo ◽

Kazutaka So ◽

Norihiro Akiyama ◽

...

Keyword(s):

Mechanical Properties ◽

Histological Examination ◽

Interbody Fusion ◽

Average Pore Size ◽

Spinous Process ◽

Fibrous Tissue ◽

Porous Titanium ◽

Titanium Implants ◽

Average Pore ◽

New Generation

Object Porous biomaterials with adequate pore structure and appropriate mechanical properties are expected to provide a new generation of devices for spinal interbody fusion because of their potential to eliminate bone grafting. The purpose of this study was to evaluate the fusion characteristics of porous bioactive titanium implants using a canine anterior interbody fusion model. Methods Porous titanium implants sintered with volatile spacer particles (porosity 50%, average pore size 303 μm, compressive strength 116.3 MPa) were subjected to chemical and thermal treatments that give a bioactive microporous titania layer on the titanium surface (BT implant). Ten adult female beagle dogs underwent anterior lumbar interbody fusion at L6–7 using either BT implants or nontreated (NT) implants, followed by posterior spinous process wiring and facet screw fixation. Radiographic evaluations were performed at 1, 2, and 3 months postoperatively using X-ray fluoroscopy. Animals were killed 3 months postoperatively, and fusion status was evaluated by manual palpation and histological examination. Results Interbody fusion was confirmed in all five dogs in the BT group and three of five dogs in the NT group. Histological examination demonstrated a large amount of new bone formation with marrowlike tissue in the BT implants and primarily fibrous tissue formation in the NT implants. Conclusions Bioactive treatment effectively enhanced the fusion ability of the porous titanium implants. These findings, coupled with the appropriate mechanical properties in load-bearing conditions, indicate that these porous bioactive titanium implants represent a new generation of biomaterial for spinal interbody fusion.

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