Custom-made Titanium Implants Research Articles

Reconstruction of a rostral maxillary defect by two custom-made titanium implants following a partial maxillectomy for treatment of squamous cell carcinoma in a dog.

This case report describes the reconstruction of a rostral maxillary defect by two custom-made titanium implants following a rostral partial maxillectomy for treatment of squamous cell carcinoma (SCC) in a seven-year-old dog. An incisional biopsy and CT scan were performed to establish the diagnosis, to plan possible surgery, and to assess the margins of the tumour. The patient had no radiographic signs of metastasis at the time of diagnosis. An oblique rostral partial maxillectomy with two custom-made titanium plates was chosen as an effective oncological treatment and to maintain the cosmetic appearance. A first custom implant was designed to support the cheek and lips, and a second implant was designed to replace part of the hard palate and serve as a base for the palatal mucosal flap. Surgical treatment combined with toceranib phosphate and cimicoxib therapy provided a survival time of at least 1700 days, as the patient is still alive at time of publication. Further research is warranted to determine the oncological and cosmetic efficacy of this surgical technique for treatment of SCC in a larger group of dogs.

Revision Cranioplasty with Three-dimensional Custom-made Titanium Implants in Patients with Failed Cranioplasty

Graft failure is a common complication of cranioplasty. Revision cranioplasty is required to overcome this complication. However, no previous studies have reported outcomes in revision cranioplasty with 3-dimensional (3D) custom-made titanium implants. We describe our experience with 3D titanium implants in patients with revision cranioplasty. We evaluated 43 consecutive patients between January 2011 and December 2019 who underwent revision cranioplasty using 3D custom-made titanium implants. The 3D image of the patient's cranium and the plan to close the cranium defect were created in a virtual environment using software programs. Demographic and radiologic features were compared based on the materials used in the initial cranioplasty. Previous material was autologous graft (AG) in 27 patients and polymethyl methacrylate (PMMA) in 16 patients. The mean time without revision cranioplasty is longer in patients with PMMA implants than in patients with AG. There was no statistically significant difference in the length of hospital stay between patients with PMMA implants and patients with AG. There were no postoperative adverse events such as infection, wound dehiscence, convulsions, or epidural hematoma in 38 patients during hospitalization. Wound dehiscence developed in 5 patients and surgical repair was required in one. Initial cranioplasty with PMMA provides a longer time period than the AG before the revision. However, both of them have similar outcomes based on length of hospital stay and cranial defect area. Custom-made 3D titanium implant is a good option for revision cranioplasty to prevent implant failure and reduce patients' cosmetic concerns.

The application of three-dimensional custom-made prostheses in chest wall reconstruction after oncologic sternal resection.

As one of the cutting-edge advances in the field of reconstruction, three-dimensional (3D) printing technology has been constantly being attempted to assist in the reconstruction of complicated large chest wall defects. However, there is little literature assessing the treatment outcomes of 3D printed prostheses for chest wall reconstruction. This study aimed to analyze the surgical outcomes of 3D custom-made prostheses for the reconstruction of oncologic sternal defects and to share our experience in the surgical management of these rare and complex cases. We summarized the clinical features of the sternal tumor in our center, described the surgical techniques of the application of 3D customized prosthesis for chest wall reconstruction, and analyzed the perioperative characteristics, complications, overall survival (OS), and recurrence-free survival of patients. Thirty-twopatients with the sternal tumor who underwent chest wall resection were identified, among which 13 patients used 3D custom-made titanium implants and 13 patients used titanium mesh for sternal reconstruction. 22 cases were malignant, and chondrosarcoma is the most common type. The mean age was 46.9 years, and 53% (17/32) of the patients were male. The average size of tumor was 6.4 cm, and the mean defect area was 76.4 cm2. 97% (31/32) patients received R0 resection. Complications were observed in 29% (9/32) of patients, of which wound infection (22%, 7/32) was the most common. The OS of the patients was 72% at 5 years. We demonstrated that with careful preoperative assessment, 3D customized prostheses could be a viable alternative for complex sternal reconstruction.

Analysis of the Effectiveness of 3D Printed Patient-Specific Implants for Reconstruction of Maxillary Defect Secondary to Mucormycosis.

Patients affected with mucormycosis of maxilla have been increasing following Covid-19 infections. We followed the reconstruction of the maxilla using 3D manufactured patient-specific implants. The additive manufacturing technology is capable of fabricating custom-made titanium implants precisely for oral and maxillofacial reconstructions. To analyse the effectiveness of 3D manufactured patient-specific implants in the reconstruction of maxilla affected by mucormycosis secondary to Covid-19. Methodology:This study was conducted among 20 patients receiving patient-specific implants for surgical and prosthetic reconstruction of the maxilla. The parameters analysed at baseline, 3months, 6months, and 12months were pain, implant exposure, infection, wound dehiscence, fit of implant, postoperative surgical rating scale, and patient experience evaluation rating scale. Inferential Statistics revealed a positive correlation. From the present data, it can be concluded that within the limitations of the study, patient-specific implant systems are an effective treatment strategy for the reconstruction of the maxilla affected by mucormycosis secondary to Covid-19. More studies with larger sample size and longer follow-up periods are required to substantiate the results from the present study. The online version contains supplementary material available at 10.1007/s12663-023-01922-7.

Simultaneous Closure Of Bilateral Cranial Defects Using Custom-Made 3D Titanium Implants- A Single Institution Series.

Closure of bilateral cranial defects using custom-made implants is challenging for neurosurgeons due to enlarging defect areas and challenges in developing materials or techniques such as mirror imaging. This study presents the outcomes of the simultaneous closure of bilateral cranial defects using custom-made three-dimensional (3D) titanium implants. Demographic data of 26 patients with bilateral cranial defects who underwent cranioplasty using the 3D custom-made titanium implants in our clinic between 2017 and 2022 were retrospectively reviewed. Data on the area of cranium defect, the time interval between last cranial surgery and cranioplasty, postoperative complications, etiology of the cranium defect, and hospitalization of the patient were statistically evaluated. The incidence of bilateral cranioplasty was 19.11%. The gender distribution of patients was 4 (15.4%) female and 22 (84.6%) male, with a mean age of 29.08 ± 14.65 years. The mean defect area was 35.0 ± 19.03 and 29.24 ± 22.51 cm2 on the right and left sides, respectively. The etiology of the cranium defect was gunshot wounds in 12 patients, and 14 patients had a history of trauma-related injuries such as falls and vehicle accidents. Eight patients had a history of failed cranioplasty with autologous bone. Postoperative complications were wound dehiscence in two patients and diffuse cerebral edema in one patient. No mortality was recorded. The custom-made cranioplasty is feasible for simultaneous closure of bilateral cranial defects. Many complications can be prevented by careful preoperative evaluation before surgery and an appropriate implant selection for the patient.

Cranioplasty Using Customized 3-Dimensional–Printed Titanium Implants: An International Collaboration Effort to Improve Neurosurgical Care

Evolutions in cranioplasty have allowed for the creation of customized implants via advances in 3-dimensional (3D) printing technology, although the high cost associated with this technique presents a barrier for low-income countries. Through an international collaboration, our team in Da Nang, Vietnam is able to create low-cost, customized titanium implants for patients with skull defects. We discuss the details of our collaboration and present our experience with this procedure. We conducted a retrospective review of 35 patients who underwent cranioplasty using custom-made titanium implants. The molding and implant making processes were performed by our neurosurgeons using a 3D printer donated by the United Kingdom-based nongovernmental organization Facing the World. We obtained demographic and preoperative data (reason for skull defect, location, surface area measurement of defect) and postoperative data (complications, cosmetic outcome, and patient satisfaction). The median patient age was 27 years (range, 16-60 years). Primary indications for craniectomy included traumatic brain injury from motor vehicle accident (77.1%), cerebrovascular disease (11.4%), implant failure following previous cranioplasty (5.7%), and fall (5.7%). Postoperatively, all implants were found to have an excellent fit; at 6-month follow-up, none of the implants required removal. Complications included 4 postoperative hematomas and 1 surgical site infection. All the patients had improved aesthetic appearance and high satisfaction. Cranioplasty using customized titanium implants yields excellent results for patients with skull defects, demonstrating the practicality of this technique for cranioplasty in low-income countries. Our experience highlights the importance of ongoing international collaboration to improve neurosurgical care in these countries.

Establishing a Quality Management System for Production of Certified Customised Titanium Medical Implants through Additive Manufacturing

ABSTRACTVarious cases of medical implants produced through additive manufacturing (AM) in Ti6Al4V have been reported in literature. Not all manufacturing processes used, were qualified. In striving to deliver certified AM medical implants and devices, an ISO 13485:2016 quality management system was implemented in the Centre for Rapid Prototyping and Manufacturing (CRPM) of the Central University of Technology, Free State (CUT) in Bloemfontein, South Africa. This certification is valid for design, development and production of patient-specific custom-made titanium implants, preoperative models, jigs and cutting-guides in nylon through AM, and contract-production of these products. For maintaining this quality management system, the generation of data to validate the individual processes in the AM process-chain is crucial to prove the DMLS product-quality of CRPM’s products. During the past five years, directed research data was produced and published to prove that medical implants produced through DMLS can fully comply with the accepted international standards for material, physical, chemical and mechanical properties of such parts. The paper discusses the quality management system’s establishment; materials research projects executed to generate validation data are mentioned; and examples of customised titanium implants for restoring the quality of life of patients are shown.

Surface modification of titanium manufactured through selective laser melting inhibited osteoclast differentiation through mitogen-activated protein kinase signaling pathway.

Selective laser melting used in manufacturing custom-made titanium implants becomes more popular. In view of the important role played by osteoclasts in peri-implant bone resorption and osseointegration, we modified selective laser melting-manufactured titanium surfaces using sandblasting/alkali-heating and sandblasting/acid-etching, and investigated their effect on osteoclast differentiation as well as their underlying mechanisms. The properties of the surfaces, including elements, roughness, wettability and topography, were analyzed. We evaluated the proliferation and morphology of primary mouse bone marrow-derived monocytes, as well as induced osteoclasts derived from bone marrow-derived monocytes, on samples. Then, osteoclast differentiation was determined by the tartrate-resistant acid phosphatase activity assay, calcitonin receptors immunofluorescence staining and the expression of osteoclast-related genes. The results showed that sandblasting/alkali-heating established nanonet structure with the lowest water contact angle, and both sandblasting/alkali-heating and sandblasting/acid-etching significantly decreased surface roughness and heterogeneity compared with selective laser melting. Surface modifications of selective laser melting-produced titanium altered bone marrow-derived monocyte morphology and suppressed bone marrow-derived monocyte proliferation and osteoclastogenesis in vitro (sandblasting/alkali-heating>sandblasting/acid-etching>selective laser melting). These surface modifications reduced the activation of extracellular signal-regulated kinase and c-Jun N-terminal kinases compared to native-selective laser melting. Sandblasting/alkali-heating additionally blocked tumor necrosis factor receptor-associated factor 6 recruitment. The results suggested that sandblasting/alkali-heating and sandblasting/acid-etching modifications on selective laser melting titanium could inhibit osteoclast differentiation through suppressing extracellular signal-regulated kinase and c-Jun N-terminal kinase phosphorylation in mitogen-activated protein kinase signaling pathway and provide a promising technique which might reduce peri-implant bone resorption for optimizing native-selective laser melting implants.

Full-Digital Workflow for Fabricating a Custom-Made Direct Metal Laser Sintering (DMLS) Mandibular Implant: A Case Report

Direct Laser Metal Sintering (DLMS) is an additive manufacturing (AM) technique that is capable of manufacturing metal parts according to a three-dimensional (3D) design made using computer-assisted-design (CAD) software, thanks to a powerful laser beam that melts selectively micro-powder layers, one on top of the other, until the desired object is generated. With DMLS, it is now possible to fabricate custom-made titanium implants for oral and maxillofacial applications. We present the case of a 67-year-old woman diagnosed with a squamous cell carcinoma of the mandible. The patient underwent subtotal mandibular resection; conventional reconstruction procedures failed to rehabilitate the function of the mandible. A prosthesis replacing the resected mandible was designed and fabricated using a digital workflow. The extensive bone defect was rehabilitated with a prosthesis replacing the mandibular bone and supporting a morse-taper dental prosthesis. The masticatory function was reestablished.

Reconstruction of complex mandibular defects using integrated dental custom-made titanium implants

Reconstruction of complex mandibular defects using integrated dental custom-made titanium implants

Customised Cranioplasty Implant for Decompressive Craniectomy Patients ? A Technical Note.

Cranioplasty is a commonly performed procedure following decompressive craniectomy. The patients are usually young earning persons and increasing cost of treatment is difficult to bear especially in low and middle income countries. A variety of options are available for cranioplasty ranging from autologus bone graft to xenograft and synthetic materials. Presently the autologous cryopreserved or subcutaneously preserved bone graft is considered as the preferred choice, but it has the drawbacks of bone resorption and infection. Custom made titanium implants and polyetheretherketone implants, which are manufactured using 3D printing technologies, are also being used. However, their use is limited because of high cost and lack of availability of these technologies in the developing world, which have the maximum number of such cases. The authors present an easy and low cost technique for making a customised cranioplasty implant by polymethylmethacrylate using the craniotomy bone flap of the patient as a template.

Computer-based surgical planning and custom-made titanium implants for cranial fibrous dysplasia.

The procedure of reconstruction after the removal of cranial fibrous dysplasia (FD) must be precise to achieve good functional and aesthetic results. Intraoperative modeling of implants is difficult and may cause cosmetic disturbances. To present our experience with the treatment of cranial FD using preoperative computer-based surgical planning of tumor removal with reconstruction of the cranium with custom-made titanium implants. Four patients underwent surgical treatment for cranial FD over a 2-year period. All patients were male with a mean age of 25.25 years and had monostotic-type FD. Computed tomography (CT) with 0.5-mm slices was obtained preoperatively. Computer-based planning of the tumor removal was performed, and a template was created by the computer to determine the margins of tumor removal. After this procedure, the preoperative computer-based construction of the titanium implant was performed. The patients underwent surgical treatment, and the tumor was removed with the use of this template. Then, the titanium implant was inserted onto the bone defect and fixed with mini-screws. Patients were followed up by periodic CT scans. The histological diagnosis of all patients was FD. No intraoperative or postoperative complications have occurred. Postoperative CT scans showed complete tumor removal and confirmed appropriate cosmetic reconstruction. The mean follow-up period was 15.25 months. Computer-based surgical planning associated with the production of custom-made titanium implants is a highly promising method for the treatment of cranial FD. Better radiological and cosmetic outcomes could be obtained by this technique with interdisciplinary work with medical designers.

Comparative evaluation of the combined application of titanium implants and calcium phosphate bone substitutes in a rabbit model.

To study the healing of defects around titanium implants filled with biphasic calcium phosphates (BCP). Forty custom-made, titanium implants (Ti) with a diameter of 5mm, and length of 8mm, with two-sided gaps, were fabricated and installed in the femoral condyle of 20 rabbits. Following a randomization protocol, implants were alternately installed in one condyle without BCP bone substitute material (Ti) in the gaps and in the contralateral condyle gaps were filled with BCP bone substitute material (Ti+BCP). The implants were retrieved after 4 and 12weeks of healing, after which histological and histomorphometrical analyses were done to assess the percentage of bone implant contact (BIC), the percentage of bone area (BA) and the percentage of particle area (PA) within the region of interest (ROI); the rectangular area joining the two arms of the L-shaped implant was considered as the ROI. After 4 and 12weeks of healing, Ti+BCP showed significantly higher BIC and BA values compared to Ti. Further, the BCP particles showed a significant decrease from 4 to 12weeks of healing. The BCP particles (PA) showed a significant reduction from 31.6±11.0% at 4weeks to 21.0±7.2% at 12weeks. The addition of BCP bone substitute to fill peri-implant gaps significantly enhanced both bone formation (~2.5-fold) and bone to implant contact (>2-fold) for the custom-made titanium implants with two-sided gaps.

In vivo monitoring of implant osseointegration in a rabbit model using acoustic sound analysis

Implant osseointegration can currently only be assessed reliably post mortem. A novel method that relies on the principle of acoustic sound analysis was developed to enable examination of the longitudinal progress of osseointegration. The method is based on a magnetic sphere inside a hollow cylinder of the implant. By excitation using an external magnetic field, collision of the sphere inside the implant produces a sound signal. Custom-made titanium implants equipped thusly were inserted in each lateral femoral epicondyle of 20 New Zealand White Rabbits. Two groups were investigated: Uncoated, machined surface versus antiadhesive surface; and calcium phosphate-coated surface versus antiadhesive surface. The sound analysis was performed postoperatively and weekly. After 4 weeks, the animals were euthanized, and the axial pull-out strengths of the implants were determined. A significant increase in the central frequency was observed for the loose implants (mean pull-out strength 21.1 ± 16.9 N), up to 6.4 kHz over 4 weeks. In comparison, the central frequency of the osseointegrated implants (105.2 ± 25.3 N) dropped to its initial value. The presented method shows potential for monitoring the osseointegration of different implant surfaces and could considerably reduce the number of animals needed for experiments.

In vivoassessment of the effect of controlled high- and low-frequency mechanical loading on peri-implant bone healing

The aim of this study was to investigate the effect of controlled high- (HF) and low-frequency (LF) mechanical loading on peri-implant bone healing. Custom-made titanium implants were inserted in both tibiae of 69 adult Wistar rats. For every animal, one implant was loaded by compression through the axis of tibia (test), whereas the other one was unloaded (control). The test implants were randomly distributed among four groups receiving different loading regimes, which were determined by ex vivo calibration. Within the HF (40 Hz) or LF (2 Hz) loading category, the magnitudes were chosen as low- (LM) and high-magnitude (HM), respectively, leading to constant strain rate amplitudes for the two frequency groups. This resulted in the four loading regimes: (i) HF-LM (40 Hz-0.5 N); (ii) HF-HM (40 Hz-1 N); (iii) LF-LM (2 Hz-10 N); and (iv) LF-HM (2 Hz-20 N) loading. Loading was performed five times per week and lasted for one or four weeks. Tissue samples were processed for histology and histomorphometry (bone-to-implant contact, BIC; and peri-implant bone fraction, BF) at the cortical and medullar level. Data were analysed statistically with ANOVA and paired t-tests with the significance level set at 0.05. For the one-week experiments, an increased BF adjacent to the implant surface at the cortical level was exclusively induced by the LF-HM loading regime (2 Hz-20 N). Four weeks of loading resulted in a significant effect on BIC (and not on BF) in case of HF-LM loading (40 Hz-0.5 N) and LF-HM loading (2 Hz-20 N): BIC at the cortical level significantly increased under both loading regimes, whereas BIC at the medullar level was positively influenced only in case of HF-LM loading. Mechanical loading at both HF and LF affects osseointegration and peri-implant BF. Higher loading magnitudes (and accompanying elevated tissue strains) are required under LF loading to provoke a positive peri-implant bone response, compared with HF loading. A sustained period of loading at HF is needed to result in an overall enhanced osseointegration.

Loaded Custom‐Made Zirconia and Titanium Implants Show Similar Osseointegration: An Animal Experiment

Zirconia might be an alternative material to titanium for dental implant fabrication. The aim of the present study was to investigate the histological behavior (osseointegration) of loaded zirconia implants in an animal model and to compare it with the behavior of titanium implants. Five months after extraction of the upper anterior teeth, 12 custom-made titanium implants (control group) and 12 custom-made zirconia implants (test group) were inserted in the extraction sites in six monkeys. Before insertion, the titanium implant surfaces were sandblasted with Al2O3 and subsequently acid-etched. The zirconia implants were only sandblasted. Six months following implant insertion, impressions were taken for the fabrication of single crowns. A further 3 months later, nonprecious metal crowns were inserted. Five months after insertion of the crowns, the implants with the surrounding hard and soft tissues were harvested, histologically prepared, and evaluated under the light microscope regarding the peri-implant soft tissue dimensions and mineralized bone-to-implant contact. No implant was lost during the investigational period. The mean height of the soft peri-implant tissue cuff was 5 mm around the titanium implants and 4.5 mm around the zirconia implants. No statistically significant differences were found in the extent of the different soft tissue compartments. The mean mineralized bone-to-implant contact after 9 months of healing and 5 months of loading amounted to 72.9% (SD: 14%) for the titanium implants and to 67.4% (SD: 17%) for the zirconia implants. There was no statistically significant difference between the different implant materials. Within the limits of this animal experiment, it can be concluded that the custom-made zirconia implants osseointegrated to the same extent as custom-made titanium control implants and show the same peri-implant soft tissue dimensions.