Sürdürülebilir Kalkınma Amaçları

  • MakaleAçık Erişim2026Scopus SJRQ2
    Bioinspired Sternal Implant Design for Generic Anatomical Reconstruction: An In Silico Framework for Material Selection and Biomechanical Validation

    Kutbay, Işıl; Gerdan, Zeynep; Çolak, Murat; Tabak, Yasemin; Şensoy, Abdullah Tahir

    The sternum protects the intrathoracic organs and contributes to chest wall mechanics, which makes reconstruction after tumor resection, trauma, or infection a demanding biomechanical problem. This study presents an in silico workflow for preselecting materials for sternal implants before physical prototyping. After a virtual resection, an anatomically conformal implant was designed and candidate biomaterials were screened in CES Selector using density, elastic modulus, fatigue strength, fracture toughness, toxicity, medical grade suitability, and MRI safety. A representative subset of the screened candidates was then compared by finite element modeling in terms of stress transfer and deformation. Seventeen candidates met the screening criteria. Ti-13Nb-13Zr showed an elastic modulus of about 80 GPa, and the titanium-based candidates showed deformation values of about 0.96 to 1.03 mm, whereas GF PEEK reached about 1.74 mm. The stress shielding index also showed that titanium-based materials remained on the implant-dominant side, while polymer-based materials shifted stress transfer toward bone. Taken together, the findings suggest that Ti-13Nb-13Zr offers the best overall balance for load-bearing sternal reconstruction, whereas PEEK-based systems may be more suitable within the present model for hybrid or adjunct designs. The proposed workflow can support early implant planning and guide future experimental and clinical studies.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleYalnız künye2026Scopus SJRQ2
    Effect of Erbium Addition to A380 Aluminum Alloy on Mechanical and Microstructural Properties

    Gültekin, Çağrı; Çolak, Murat; Tabak, Yasemin; Şensoy, Abdullah Tahir

    There are many studies on improving the properties of aluminum alloys, but the addition of rare earth elements occupies a particularly important place among them. In this study, the effect of erbium (Er) addition on the microstructure and mechanical properties of A380 aluminum casting alloy was systematically investigated. A series of alloys with varying Er contents (0.03%, 0.05% and 0.1 wt.%) was fabricated using the conventional casting method. The addition of Er led to significant grain refinement, primarily due to the formation of Al3Er intermetallic particles, which acted as potent nucleation sites during solidification. Optical microscopy and SEM analyses confirmed the morphological transformation of the eutectic silicon phase into a finer and more fibrous structure. Mechanical testing revealed that the alloy containing 0.1 wt.% Er exhibited the highest ultimate tensile strength (236 MPa), elongation (4.56%), and hardness (87.6 HB), indicating an optimal balance between strength and ductility. The improvement is attributed to both microstructural refinement and dispersion strengthening mechanisms. These results suggest that controlled Er addition can be an effective strategy for enhancing the performance of cast Al–Si alloys, making them promising candidates for demanding structural applications in the automotive and aerospace industries.

    AtıfScopus3WoS1
    ScopusWeb of Scienceİncele
  • Derleme MakaleAçık Erişim2026Scopus SJRQ2
    Titanium and polyetheretherketone for spinal fusion cages: a comparative narrative review of material behavior, structural design, and clinical translation

    Hasheminasab; Bazmi, Arian; Hamsianetefagh, Rojin; Tabak, Yasemin; Ashkani, Omid; Mahboubizadeh, Shahram; Colak, Murat; Şensoy, Abdullah Tahir

    Cage material selection in spinal fusion requires a trade-off among biological fixation, mechanical compatibility, subsidence resistance, and postoperative imaging. This structured narrative review compares titanium and polyetheretherketone (PEEK) cages across seven domains: osseointegration, modulus matching, endplate load transfer, surface biofunctionality, imaging, additive manufacturing and personalization, and geometry-guided architecture. Peer-reviewed literature indexed in PubMed/MEDLINE, Scopus, and Web of Science was considered from database inception through May 2026, with emphasis on comparative clinical studies, systematic reviews, meta-analyses, and mechanistic studies directly relevant to cage design. Preclinical studies favor porous and additively manufactured titanium for bone–implant integration, but a consistent fusion-rate advantage in anterior cervical discectomy and fusion (ACDF) has not been established. In lumbar surgery, lower subsidence has been reported in selected lateral lumbar interbody fusion cohorts, while results after transforaminal lumbar interbody fusion remain heterogeneous. PEEK retains advantages in radiolucency and intrinsic modulus matching, while surface-modified and porous PEEK can improve biological performance. Subsidence is not determined by chemistry alone; cage footprint, architecture, endplate preparation, fixation, and bone quality remain major modifiers. Current evidence therefore supports procedure and design-specific selection rather than universal replacement of either platform. Long-term comparative data and standardized definitions of fusion and subsidence remain limited.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleAçık Erişim2020Scopus SJRQ1
    Development of particle swarm and topology optimization-based modeling for mandibular distractor plates

    Şensoy, Abdullah Tahir; Kaymaz, Irfan; Ertaş, Ümit

    Mandibular Distraction Osteogenesis (MDO) is a common clinical procedure to correct mandibular retrognathia. However, since there is not a gold standard for determining the screw positions for current MDO operations, deviation of distraction direction and malocclusion increases. This case results in need of additional operations that affect the callus stability. In these cases, relapse risk increases and remodelling period gets longer. On the other hand, large volume of the distractor plates results in more invasive treatment and negatively affects the patients’ comfort. To overcome these problems, this study offers a new method including; virtual surgery simulation, determining the optimum screw configuration using particle swarm optimization loop linked between MATLAB-PYTHON-ANSYS programs and the design of distractor plate geometry with topology optimization. In order to test the proposed method, two different Finite Element (FE) models, CM and OM, were established based on conventional and optimum method, respectively. FEA results of the current study reveals that OM has 33.56% less displacement compared to CM, and the most critical screw in terms of screw loosening for OM has 35.29% less strain value than CM. These outcomes show OM shows superior callus stability in comparison with CM. On the other hand, redesign of the distractor plates using topology optimization according to the best screw positions provides 43.32% reduction in the total implant volume which means reduced cost and a less invasive MDO operation. Therefore, the clinical use of this protocol is expected to increase the success of the operation by shortening the recovery period.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus13WoS11OpenAlex13
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2020Scopus SJRQ2
    Investigating the Optimum Model Parameters for Casting Process of A356 Alloy: A Cross-validation Using Response Surface Method and Particle Swarm Optimization

    Şensoy, Abdullah Tahir; Çolak, Murat; Kaymaz, Irfan; Dispinar, Derya

    This study aimed to determine the optimal casting parameters for the maximum fluidity of A356 alloy. Gravity die cast method was used. For this purpose, central composite design (CCD) was performed. The input parameters and their limits for the trial design were selected as pre-heating temperature (100–400 °C), casting temperature (680–760 °C), and cross-sectional thickness (1–10 mm). Using the CCD-based simulation results of the feed distance, a highly correlated full-quadratic regression equation was obtained with the highest R2 (0.99), which then was used as the objective function for the particle swarm optimization (PSO) process. The highest value of the response parameter, flow distance, reached up to 491.19 mm when the input parameters were selected as 400 °C, 760 °C and 10 mm, respectively. The sensitivity analysis has shown that the most effective parameter on the fluidity is the cross-sectional thickness. The response surface method (RSM)-based optimization results have been also validated using the PSO method. Although the higher temperatures have been found to result in better fluidity, there may be some drawbacks to working at higher temperatures such as energy cost and mould life. To determine the optimum input parameters, the RSM model suggested in this study can be modified for any type of casting process. Moreover, especially for a complex-shaped part, the manufacturer can be advised regarding operating conditions such as pre-heating and casting temperatures.

    AtıfScopus11WoS9OpenAlex13
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  • MakaleAçık Erişim2020Scopus SJRQ3
    Determining the optimum model parameters for oligosaccharide production efficiency using response surface integrated particle swarm optimization method: an experimental validation study

    Şensoy, Abdullah Tahir; İspirli, Hümeyra; Dertli, Enes

    Glucansucrases (GTFs) catalyzes the synthesis of α-glucans from sucrose and oligosaccharides in the presence of an acceptor sugar by transferring glucosyl units to the acceptor molecule with different linkages. The acceptor reactions can be affected by several parameters and this study aimed to determine the optimal reaction parameters for the production of glucansucrase-based oligosaccharides using sucrose and maltose as the donor and acceptor sugars, respectively via a hybrid technique of Response Surface Method (RSM) and Particle Swarm Optimization (PSO). The experimental design was performed using Central Composite Design and the tested parameters were enzyme concentration, acceptor:donor ratio and the reaction period. The optimization studies showed that enzyme concentration was the most effective parameter for the final oligosaccharides yields. The optimal values of the significant parameters determined for enzyme concentration and acceptor:donor ratio were 3.45 U and 0.62, respectively. Even the response surface plots for input parameters verified the PSO results, an experimental validation study was performed for the reverification. The experimental verification results obtained were also consistent with the PSO results. These findings will help our understanding in the role of different parameters for the production of oligosaccharides in the acceptor reactions of GTFs.

    AtıfScopus6WoS6OpenAlex6
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2019
    Functionally Graded Porous Implants Obtained by Additive Manufacturing

    Murat, Fahri; Şensoy, Abdullah Tahir; Korkmaz, İsmail Hakkı; Kaymaz, Irfan

    Porous structures have an increasing use in the biomedical industry due to their advantage, such as supporting tissue regeneration for implants and prostheses used in the body, eliminating stress shielding and aseptic loosening problems. Although porous structures with homogeneous density contributed positively to biological processes, these structures were insufficent to exhibit the desired mechanical properties. The implant to be used in this case should offer the optimum design both biologically and mechanically. In order to solve this problem, functionally graded structures which provide the harmony of tissue regeneration and mechanical behaviour on the load bearing orthopedic implant are presented. The design where porosity is very dense in the load-bearing sections of the implant and less dense in the areas in contact with the tissue have become feasible by the additive manufacturing methods. In this study, the recent developments in the literature on porous implants, functionally graded porous structures and additive manufacturing applications of these structures have been compiled. As a result, a procedure is presented on porous implant designs that will be used to improve mechanical properties by accelerating biological healing processes in additive manufacturing applications.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
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  • MakaleAçık Erişim2019Scopus SJRQ2
    Optimal Material Selection for Total Hip Implant: A Finite Element Case Study

    Şensoy, Abdullah Tahir; Çolak, Murat; Kaymaz, Irfan; Findik, Fehim

    The selection of most proper materials in engineering design is known as an important stage of the design process. In order to successfully complete this stage, it is necessary to have sufficient knowledge about the structure of materials, density, melting point, thermal expansion coefficient, tensile and yield strength, elongation, modulus of elasticity, hardness and many other properties. There are several selection systems that help the design engineer to choose most suitable material that meet the required properties. In the field of bioengineering, the selection of materials and the development of new materials for the clinical needs are increasingly important. In this study, the cases of optimal implant stabilization were investigated, material alternatives for hip prosthesis were evaluated, and optimal materials were determined. Using computerized tomography data with MIMICS software, virtual surgery was applied the hip bone and the implant was attached to bone. Boundary conditions and material properties have been defined, and finite element model has been created. FEA investigation of the mechanical behavior of the hip implant for various material alternatives determined by the CES software showed that the best material candidate is austenitic, annealed and biodurable stainless steel in terms of the micromotions at the implant–bone cement interface regarding osseointegration. This candidate showed 20.69% less strain value than the most commercially used hip implant material, Ti6Al4V. Therefore, the findings of this study suggest that the use of some specific stainless steel materials for implants may reduce the operation cost and increase the operation success for the total hip arthroplasty.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus36WoS28OpenAlex41
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2018Scopus SJRQ2
    Determining the Patient-Specific Optimum Osteotomy Line for Severe Mandibular Retrognathia Patients

    Şensoy, Abdullah Tahir; Kaymaz, Irfan; Ertaş, Ümit; Kiki, Ali

    Purpose: The purpose of this study is to suggest a patient-specific osteotomy line to optimize the distractor position and thus to minimize the disadvantages of conventional mandibular distraction osteogenesis (MDO) protocols. In addition, this study also aims to compare the conventional MDO protocols with the new MDO protocol proposed in this study in terms of both orthodontic outcomes and mechanical effects of osteotomy level on callus stabilization by means of the finite element method. Methods: A preoperative patient-specific 3-dimensional bone model was created and segmented by using computed tomography images of an individual patient. Virtual orthodontic set-up was applied to the segmented model prior to the virtual surgery. In order to compare the proposed osteotomy line with the conventional lines used in clinical applications, virtual surgery simulations were performed and callus tissues were modelled for each scenario. The comparison of the success of each osteotomy line was carried out based on the occlusion of the teeth. Results: The osteotomy line determined using the method proposed in this study has resulted in far less malocclusion than the conventional method. Namely, any angular deviation from the optimum osteotomy line determined in this study might result in deep-bite or open-bite. On the other hand, the finite element analysis results have indicated that this deviation also negatively affects the callus stability. Conclusion: In order to achieve a better MDO treatment in terms of occlusion of the teeth and the callus stability, the location of the osteotomy line and the distractor position can be computationally determined. The results suggest that MDO protocol developed in this study might be used in clinic to achieve a better outcome from the MDO treatment.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus7WoS4OpenAlex8
    ScopusWeb of SciencePubMedİncele