Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2014
This article describes the development of a partially degradable metal bone pin, proposed to mini... more This article describes the development of a partially degradable metal bone pin, proposed to minimize the occurrence of bone refracture by avoiding the creation of holes in the bone after pin removal procedure. The pin was made by friction welding and composed of two parts: the degradable part that remains in the bone and the nondegradable part that will be removed as usual. Rods of stainless steel 316L (nondegradable) and pure iron (degradable) were friction welded at the optimum parameters: forging pressure = 33.2 kPa, friction time = 25 s, burn-off length = 15 mm, and heat input = 4.58 J/s. The optimum tensile strength and elongation was registered at 666 MPa and 13%, respectively. A spiral defect formation was identified as the cause for the ductile fracture of the weld joint. A 40-µm wide intermetallic zone was identified along the fusion line having a distinct composition of Cr, Ni, and Mo. The corrosion rate of the pin gradually decreased from the undeformed zone of pure iron to the undeformed zone of stainless steel 316L. All metallurgical zones of the pin showed no toxic effect toward normal human osteoblast cells, confirming the ppb level of released Cr and Ni detected in the cell media were tolerable.
The recent proposal of using Zn-based alloys for biodegradable implants was not supported with su... more The recent proposal of using Zn-based alloys for biodegradable implants was not supported with sufficient toxicity data. This work, for the first time, presents a thorough cytotoxicity evaluation of Zn-3Mg alloy for biodegradable bone implants. Normal human osteoblast cells were exposed to the alloy's extract and three main cell-material interaction parameters: cell health, functionality and inflammatory response, were evaluated. Results showed that at the concentration of 0.75mg/ml alloy extract, cell viability was reduced by ~50% through an induction of apoptosis at day 1; however, cells were able to recover at days 3 and 7. Cytoskeletal changes were observed but without any significant DNA damage. The downregulation of alkaline phosphatase protein levels did not significantly affect the mineralization process of the cells. Significant differences of cyclooxygenase-2 and prostaglandin E2 inflammatory biomarkers were noticed, but not interleukin 1-beta, indicating that the cells underwent a healing process after exposure to the alloy. Detailed analysis on the cell-material interaction is further discussed in this paper.
The recent proposal of using Zn-based alloys for biodegradable implants was not supported with su... more The recent proposal of using Zn-based alloys for biodegradable implants was not supported with sufficient toxicity data. This work, for the first time, presents a thorough cytotoxicity evaluation of Zn–3Mg alloy for biodegradable bone implants. Normal human osteoblast cells were exposed to the alloy's extract and three main cell–material interaction parameters: cell health, functionality and in"ammatory response, were evaluated. Results showed that at the concentration of 0.75 mg/ml alloy extract, cell viability was reduced by ~50% through an induction of apoptosis at day 1; however, cells were able to recover at days 3 and 7. Cytoskeletal changes were observed but without any significant DNA damage. The downregulation of alkaline phosphatase protein levels did not significantly affect the mineralization process of the cells. Signi!cant differences of cyclooxygenase-2 and prostaglandin E2 inflammatory biomarkers were noticed, but not interleukin 1-beta, indicating that the ...
European Cells and Materials Vol. 28. Suppl. 3, 2014 (page 81)
INTRODUCTION: Fe-5wt%HA composite has been shown a good in vitro cellular activity and evidence o... more INTRODUCTION: Fe-5wt%HA composite has been shown a good in vitro cellular activity and evidence of a gradual in vivo degradation of its implants in the radial bone of sheep based on radiodensity image analysis [1,2]. The present work aims to analyze peri-implant osseointegration and osteoconduction of the composite compared to SS316L after their implantation in medio-proximal region of sheep radial bones. METHODS: Five male sheep (age 10-12 month, weight 14-16 kg) were used. The implants were inserted into prepared defects where one sheep received one implant on each leg. The venous blood was collected and centrifuged at day 60. The Fe and Ca ions concentration were measured using an AA-7000 atomic absorption spectrophotometer (Shimadzu, Japan) and P concentration using a UV-200RS spectrometer (LW Scientific, USA) at 660 nm. The implants were viewed by VR-1020 X-ray radiography (Medical Corp, Japan) and then peri-implant gray scale was analyzed using Image-J software (NIH, USA) at day 60. The bone and implant were biopsied for histological examination at day 70. The tissues were then embedded in paraffin block and sliced at 5 µm thickness by microtome for hematoxylin and eosin stain. RESULTS: Fig. 1 shows radiographic peri-implant images analysis for both implants at day 70 post-implantation. The peri-implant density of Fe-HA implant higher than SS316L was observed.
Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2014
This article describes the development of a partially degradable metal bone pin, proposed to mini... more This article describes the development of a partially degradable metal bone pin, proposed to minimize the occurrence of bone refracture by avoiding the creation of holes in the bone after pin removal procedure. The pin was made by friction welding and composed of two parts: the degradable part that remains in the bone and the nondegradable part that will be removed as usual. Rods of stainless steel 316L (nondegradable) and pure iron (degradable) were friction welded at the optimum parameters: forging pressure = 33.2 kPa, friction time = 25 s, burn-off length = 15 mm, and heat input = 4.58 J/s. The optimum tensile strength and elongation was registered at 666 MPa and 13%, respectively. A spiral defect formation was identified as the cause for the ductile fracture of the weld joint. A 40-µm wide intermetallic zone was identified along the fusion line having a distinct composition of Cr, Ni, and Mo. The corrosion rate of the pin gradually decreased from the undeformed zone of pure iron to the undeformed zone of stainless steel 316L. All metallurgical zones of the pin showed no toxic effect toward normal human osteoblast cells, confirming the ppb level of released Cr and Ni detected in the cell media were tolerable.
Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2014
This article describes the development of a partially degradable metal bone pin, proposed to mini... more This article describes the development of a partially degradable metal bone pin, proposed to minimize the occurrence of bone refracture by avoiding the creation of holes in the bone after pin removal procedure. The pin was made by friction welding and composed of two parts: the degradable part that remains in the bone and the nondegradable part that will be removed as usual. Rods of stainless steel 316L (nondegradable) and pure iron (degradable) were friction welded at the optimum parameters: forging pressure = 33.2 kPa, friction time = 25 s, burn-off length = 15 mm, and heat input = 4.58 J/s. The optimum tensile strength and elongation was registered at 666 MPa and 13%, respectively. A spiral defect formation was identified as the cause for the ductile fracture of the weld joint. A 40-µm wide intermetallic zone was identified along the fusion line having a distinct composition of Cr, Ni, and Mo. The corrosion rate of the pin gradually decreased from the undeformed zone of pure iron to the undeformed zone of stainless steel 316L. All metallurgical zones of the pin showed no toxic effect toward normal human osteoblast cells, confirming the ppb level of released Cr and Ni detected in the cell media were tolerable.
The recent proposal of using Zn-based alloys for biodegradable implants was not supported with su... more The recent proposal of using Zn-based alloys for biodegradable implants was not supported with sufficient toxicity data. This work, for the first time, presents a thorough cytotoxicity evaluation of Zn-3Mg alloy for biodegradable bone implants. Normal human osteoblast cells were exposed to the alloy's extract and three main cell-material interaction parameters: cell health, functionality and inflammatory response, were evaluated. Results showed that at the concentration of 0.75mg/ml alloy extract, cell viability was reduced by ~50% through an induction of apoptosis at day 1; however, cells were able to recover at days 3 and 7. Cytoskeletal changes were observed but without any significant DNA damage. The downregulation of alkaline phosphatase protein levels did not significantly affect the mineralization process of the cells. Significant differences of cyclooxygenase-2 and prostaglandin E2 inflammatory biomarkers were noticed, but not interleukin 1-beta, indicating that the cells underwent a healing process after exposure to the alloy. Detailed analysis on the cell-material interaction is further discussed in this paper.
The recent proposal of using Zn-based alloys for biodegradable implants was not supported with su... more The recent proposal of using Zn-based alloys for biodegradable implants was not supported with sufficient toxicity data. This work, for the first time, presents a thorough cytotoxicity evaluation of Zn–3Mg alloy for biodegradable bone implants. Normal human osteoblast cells were exposed to the alloy's extract and three main cell–material interaction parameters: cell health, functionality and in"ammatory response, were evaluated. Results showed that at the concentration of 0.75 mg/ml alloy extract, cell viability was reduced by ~50% through an induction of apoptosis at day 1; however, cells were able to recover at days 3 and 7. Cytoskeletal changes were observed but without any significant DNA damage. The downregulation of alkaline phosphatase protein levels did not significantly affect the mineralization process of the cells. Signi!cant differences of cyclooxygenase-2 and prostaglandin E2 inflammatory biomarkers were noticed, but not interleukin 1-beta, indicating that the ...
European Cells and Materials Vol. 28. Suppl. 3, 2014 (page 81)
INTRODUCTION: Fe-5wt%HA composite has been shown a good in vitro cellular activity and evidence o... more INTRODUCTION: Fe-5wt%HA composite has been shown a good in vitro cellular activity and evidence of a gradual in vivo degradation of its implants in the radial bone of sheep based on radiodensity image analysis [1,2]. The present work aims to analyze peri-implant osseointegration and osteoconduction of the composite compared to SS316L after their implantation in medio-proximal region of sheep radial bones. METHODS: Five male sheep (age 10-12 month, weight 14-16 kg) were used. The implants were inserted into prepared defects where one sheep received one implant on each leg. The venous blood was collected and centrifuged at day 60. The Fe and Ca ions concentration were measured using an AA-7000 atomic absorption spectrophotometer (Shimadzu, Japan) and P concentration using a UV-200RS spectrometer (LW Scientific, USA) at 660 nm. The implants were viewed by VR-1020 X-ray radiography (Medical Corp, Japan) and then peri-implant gray scale was analyzed using Image-J software (NIH, USA) at day 60. The bone and implant were biopsied for histological examination at day 70. The tissues were then embedded in paraffin block and sliced at 5 µm thickness by microtome for hematoxylin and eosin stain. RESULTS: Fig. 1 shows radiographic peri-implant images analysis for both implants at day 70 post-implantation. The peri-implant density of Fe-HA implant higher than SS316L was observed.
Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2014
This article describes the development of a partially degradable metal bone pin, proposed to mini... more This article describes the development of a partially degradable metal bone pin, proposed to minimize the occurrence of bone refracture by avoiding the creation of holes in the bone after pin removal procedure. The pin was made by friction welding and composed of two parts: the degradable part that remains in the bone and the nondegradable part that will be removed as usual. Rods of stainless steel 316L (nondegradable) and pure iron (degradable) were friction welded at the optimum parameters: forging pressure = 33.2 kPa, friction time = 25 s, burn-off length = 15 mm, and heat input = 4.58 J/s. The optimum tensile strength and elongation was registered at 666 MPa and 13%, respectively. A spiral defect formation was identified as the cause for the ductile fracture of the weld joint. A 40-µm wide intermetallic zone was identified along the fusion line having a distinct composition of Cr, Ni, and Mo. The corrosion rate of the pin gradually decreased from the undeformed zone of pure iron to the undeformed zone of stainless steel 316L. All metallurgical zones of the pin showed no toxic effect toward normal human osteoblast cells, confirming the ppb level of released Cr and Ni detected in the cell media were tolerable.
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Papers by N.S. Murni
Inthepresentstudy,bioactivecompositescomposedofhydroxyapatite(HA)andzeolite-Yweresuccessfullysynthesizedbyusingacost-effective microwaveassistedwetprecipitationmethod.Thephasepurity,functionalgroups,surfacetopography,andelementalcompositionof
the compositematerialswereexaminedbyX-raydiffraction(XRD),Fouriertransforminfraredspectroscopy(FTIR), field emissionscanning
electron microscopy(FESEM),andenergydispersiveX-rayspectroscopy(EDX),respectively.TheXRD,FTIR,andEDXresultsconfirmed the
presence ofzeolitewithHA,demonstratingtheformationofzeolite–HA composites.FESEM findings revealedthattheparticleshadspherical
morphology. Theinvitrobioactivityassayusingsimulatedbody fluid (SBF)showedthatthesilica-basedmaterialshadtheabilitytosupportand
accelerate theformationofdenselayer.Thecellviabilityofnormalhumanosteoblast(NHOst)cellsonthecompositeswasconfirmed byusing
cytotoxicity assay.Inaddition,FESEMresultsaffirmed thatthematerialsupportedadhesionofNHOstcellsonitssurface.Inconclusion,the
nano-structured zeolite–HA compositesdevelopedinthisstudyshowedgoodbioactivityandinvitrocellcompatibility,and,therefore,maybe
considered asapotentialcandidateforbonetissueengineeringapplications.
Keywords: Biomaterial; Hydroxyapatite;Zeolite;Bioactivityandbiocompatibility;Microwaveradiations
Inthepresentstudy,bioactivecompositescomposedofhydroxyapatite(HA)andzeolite-Yweresuccessfullysynthesizedbyusingacost-effective microwaveassistedwetprecipitationmethod.Thephasepurity,functionalgroups,surfacetopography,andelementalcompositionof
the compositematerialswereexaminedbyX-raydiffraction(XRD),Fouriertransforminfraredspectroscopy(FTIR), field emissionscanning
electron microscopy(FESEM),andenergydispersiveX-rayspectroscopy(EDX),respectively.TheXRD,FTIR,andEDXresultsconfirmed the
presence ofzeolitewithHA,demonstratingtheformationofzeolite–HA composites.FESEM findings revealedthattheparticleshadspherical
morphology. Theinvitrobioactivityassayusingsimulatedbody fluid (SBF)showedthatthesilica-basedmaterialshadtheabilitytosupportand
accelerate theformationofdenselayer.Thecellviabilityofnormalhumanosteoblast(NHOst)cellsonthecompositeswasconfirmed byusing
cytotoxicity assay.Inaddition,FESEMresultsaffirmed thatthematerialsupportedadhesionofNHOstcellsonitssurface.Inconclusion,the
nano-structured zeolite–HA compositesdevelopedinthisstudyshowedgoodbioactivityandinvitrocellcompatibility,and,therefore,maybe
considered asapotentialcandidateforbonetissueengineeringapplications.
Keywords: Biomaterial; Hydroxyapatite;Zeolite;Bioactivityandbiocompatibility;Microwaveradiations