Sürdürülebilir Kalkınma Amaçları

  • MakaleAçık Erişim2021
    Biomechanical Comparison of Three Treatments for Medial Malleolar Fractures

    Yurul, Gokhan; Demri, Sukru; Gürger, Murat; Key, Sefa; Say, Yakup; Senel, Ahmet

    Amaç: İskelet sistemine ait tüm kırıklar içerisinde %10 gibi bir oranla nispeten sık görülen ayak bileği kırıkları kalça kırıklarından sonra alt ekstremitenin en sık görülen ikinci kırık türüdür. Bu çalışmada, medial malleolün transvers kırıklarında medial malleol plağı, hazır gergi bandı, malleol vidası yöntemlerinin biyomekanik olarak karşılaştırılması amaçlanmıştır. Yöntemler: Kasaptan, insan tüketimi için kesilmiş, yumuşak dokularından arındırılmış 42 adet inek tibiası temin edildi. Çalışma kapsamına alınan kemiklerin medial malleollerine kesici motor yardımıyla transvers kırıklar oluşturuldu ve her biri 14 kemikten oluşan 3 gruba ayrıldı. Bu 3 gruptaki oluşturulmuş olan medial malleol kırıkları hazır gergi bandı, malleol vidası, medial malleol plağı kullanılarak usulüne uygun tespit edildi. Örnekler laboratuvarda çekme kuvveti ve transvers kuvvet uygulayan test cihazında hazırlanmış aparatlar yardımıyla biyomekanik analize tabi tutuldu. Alınan veriler kuvvetdeplasman eğrilerine dönüştürülerek yorumlandı. Bulgular: Çekme kuvvetinde medial malleol plağı yöntemi, 2 mm deplasman kuvveti ve katastrofik hasar kuvveti açısından diğer yöntemlere göre daha yüksek kuvvetlere dayanırken, dayanıklılık açısından hazır gergi bandı yöntemiyle arasında fark bulunamamıştır. Medial malleol plağı yönteminin çekme kuvvetinde malleol vidası yöntemine göre daha dayanıklı olduğu görülmüştür. Tranvers kuvvet uygulanan gruplarda 2 mm deplasman kuvvetinde medial malleol plağı yöntemi, hazır gergi bandı ve malleol vidası yöntemlerine göre daha yüksek kuvvetlere dayanabilmiştir. Transvers kuvvetlerde medial malleol plağı yöntemi, hazır gergi bandı ve malleol vidası yöntemlerine göre daha dayanıklı bulunmuştur. Sonuç: Medial malleol plağı medial malleolün transvers kırıklarında uygulanabilecek bir yöntem olup bu yöntemin olası dezavantajları için yapılacak başka çalışmalara ihtiyaç olduğunu düşünmekteyiz.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleYalnız künye2020Scopus SJRQ2
    The effect of graphene nano-sheet (GNS) weight percentage on mechanical and corrosion properties of AZ61 and AZ91 based magnesium matrix composites

    Guler, Omer; Say, Yakup; Dikici, Burak

    In this study, the effect of graphene nano-sheets (GNSs) on mechanical and corrosion properties of AZ61 and AZ91 based composites was investigated, detail. GNSs have been successfully produced by the liquid phase exfoliation (LPE) method and then, added AZ61 and AZ91 matrix with 01, 0.2, and 0.5 wt% GNSs for the production of the composites. The composite compacts were produced by powder metallurgy technique and sintered for 2 h at 500 °C under Ar atmosphere. The composite characterizations were carried out by scanning and transmission electron microscopes (SEM, TEM), electron dispersive spectroscope (EDS), Raman spectroscopy, and X-ray diffraction. The mechanical properties and corrosion behaviors of the composites have been compared with compression tests and potentiodynamic scanning (PDS) techniques, respectively. The results showed that the compressive strength of the composites increased with increasing GNS amount in both the AZ61 and AZ91 matrix alloys. The most susceptible composites to corrosion for both AZ61 and AZ91 matrix were observed in the 0.5 wt% GNS containing structures. However, there is a certain ratio of GNS in the Mg matrix to achieve good corrosion resistance.

    AtıfScopus29WoS25OpenAlex33
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2020Scopus SJRQ1
    Carbon nanotube (CNT) reinforced magnesium matrix composites: The effect of CNT ratio on their mechanical properties and corrosion resistance

    Say, Yakup; Guler, Omer; Dikici, Burak

    In this study, mechanical properties and corrosion resistance of AZ61 and AZ91 magnesium matrix composites reinforced with 01, 0.2, and 0.5 wt% carbon nanotubes (CNTs) were investigated, detailly. CNTs have been successfully synthesized with 15–20 nm diameters by chemical vapor deposition (CVD) method and then, added to magnesium alloys by using the powder metallurgy (PM) technique. The composite compacts were consolidated by cold-pressing under 500 MPa pressure and sintered for 2 h at 500 °C under Ar atmosphere. The characterization studies of the unreinforced alloys and composites were carried out by scanning and transmission electron microscopes (SEM, TEM), electron dispersive spectroscope (EDS), Raman spectroscopy, and X-ray diffraction. The mechanical properties and corrosion behaviors of the composites have been compared with compression tests and potentiodynamic scanning (PDS) techniques, respectively. The results showed that the effect of CNTs reinforcement on strength increase was greater in AZ61 series samples than AZ91-based composites. The corrosion results of the presented study showed that the composites reinforced with lower CNTs (such as 0.1 or 0.2 wt%) and unreinforced alloys had better corrosion resistance than high CNTs (such as 0.5 wt%) containing structures. However, the most resistant structure to the corrosion for both AZ61 and AZ91 alloys were obtained in the composites reinforced with 0.2 wt% CNTs.

    AtıfScopus109WoS85OpenAlex104
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2019Scopus SJRQ2
    Grape seed extract supplement increases bone callus formation and mechanical strength: an animal study

    Gurger, Murat; Yilmaz, Erhan; Yilmaz, Seval; Once, Gokhan; Konuk, Mustafa; Kaya, Emre; Say, Yakup; Artas, Gokhan; Artas, Hakan

    BackgroundThe positive effects of grape seed proanthocyanidin extract (GSPE) on bone health, which is a potent antioxidant, are known but its effects on fracture healing are not sufficiently covered in the literature. This study aims to investigate the effects of GSPE on fracture healing and biomechanics of healing bone.Materials and methodsSixty-four adult Wistar-Albino male rats were divided into 8 groups of 8 animals in each group. Osteotomy was performed to the right femurs of all groups except the negative control (G1) and positive control (G2) groups, and intramedullary Kirchner wire was used for fixation. GSPE was given to half of the rats (G2-G4-G6-G8) 100mg/kg/day by oral gavage. The rats were sacrificed on the tenth (G3-G4), twentieth (G5-G6), and thirtieth (G1-G2-G7-G8) days, respectively, and histopathological, radiological, and biomechanical examinations were performed.ResultsHistopathological examination of the specimens from the callus tissues revealed that bone healing was more prominent in the groups supplemented with GSPE (G4, G6, G8). There was a statistically significant improvement in radiological recovery scores and callus volumes in groups with GSPE. When biomechanical strengths were evaluated, it was found that GSPE increased bone strength not only in fracture groups but also in the positive control group (G2).ConclusionsAs a result, this study showed that GSPE, a potent anti-oxidant, had a positive effect on bone healing and improved mechanical strength of the healing bone.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfWoS10OpenAlex12
    Web of SciencePubMedİncele
  • MakaleYalnız künye2016Scopus SJRQ1
    Effect of hydroxyapatite/SiO2 hybride coatings on surface morphology and corrosion resistance of REX-734 alloy

    Say, Yakup; Aksakal, Bunyamin; Dikici, Burak

    REX-734 stainless steel alloy was coated with hydroxyapatite (HA)-silicon dioxide (SiO2) composite (hybride) coatings by using the sol-gel method. Surface morphologies, adhesion resistances and corrosion behaviors of the coatings were examined and the characterization of the coatings was performed by using XRD, SEM, and EDS. It was observed that porous and crack-free surface morphology enhanced adhesion strength of the coatings. Through the shear tests, it was found that the adhesion resistance was 25.14 MPa in HA coatings and 25.47 MPa in HA-SiO2 coatings. Corrosion analyses of the coatings were performed by using potentiodynamic polarization (PDS) tests. It was determined that corrosion dimples formed on the coating surface and the corrosion resistance in HA+SiO2 coatings increased with decreasing porosity; however, in the further steps of corrosion, it reached to the base material by causing a pitting effect on the coated surface. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

    AtıfWoS36OpenAlex39
    Web of Scienceİncele