CORROSION BEHAVIOR OF NITINOL VASCULAR DEVICES
Alan R. PeltonRiepe, et al. SMST 2000
Corrosion and Biocompatibility Depend on Surface Processing
7 September 2017 Greenberg Stent Summit
Jetty, et al. J Vasc Surg 2013
2
FDA Stent Guidance Document 2015
7 September 2017 Greenberg Stent Summit 3
Anodic Polarization Corrosion Resistance: Passivated and Thermal Oxide Surface
7 September 2017 Greenberg Stent Summit
ASTM F2129, PBS, 37˚C
Pelton and Blaich SurFACTS in Biomaterials 2017
4
7 September 2017 Cleveland Clinic Stent Summit
Thermal Oxide: Greater Ni-ion Release From Devices
PBS Solution, 37˚CConsistent with ISO 10993-15
Acute Ni intoxication in dialyzed patients Ni ~ 3 ppm (Webster, et al. 1980)
Ni cytotox response at > 6 ppm (Messer, et al. 2005); 9 ppm (Shih, et al. 2000)
Ni release rate in blood should not exceed 35 μg/day (Sunderman, 1983)
Ni-Ion Release After Crush Fatigue
Pelton and Blaich SurFACTS in Biomaterials 2017
6
7 September 2017 Greenberg Stent Summit
OT Inflammation
MP
SPA
F
Inflammation
in vitro and Six-Month Animal Investigation
Stacey J.L. Sullivan1
Daniel Madamba2
Shiril Sivan1
Katie Miyashiro2
Maureen L. Dreher1
Christine Trépanier2
Srinidhi Nagaraja1
Sullivan et al., Acta Biomaterialia https://doi.org/10.1016/j.actbio.2017.08.029
Nagaraja et al., SMST 2017
Ni release is not correlated to pitting potentials from ASTM F2129
7
Needle Selection for Graft Suturing Affects Corrosion
7 September 2017 Greenberg Stent Summit 8
Corrosion and Biocompatibility of Nitinol
7 September 2017 Greenberg Stent Summit
Imperative to remove Ni + Ni3Ti + TiO2 after thermal processing
Create Ni-free amorphous Ti-O surface for passivation
2015 FDA Guidelines necessary but not sufficient to predict chronic corrosion behavior
Recommend dynamic corrosion and Ni-ion release testing for vascular devices
9
SMST 2017 San Diego, CA 17 May 2017 Slide
Thank You!
10