The 7th Symposium on Biodegradable Metals

DAY one

上午

Clinics and Biometals Session I

Matthias Peuster

Biodegradable Dreadms A pediatric cardiac interventionalist’sperspective

Jilin Heart Hospital

Circulation 2011, 123:779-797

ISO25539

Potential benefits for BM

Few

No interference with MRI

Better across if crossing the septum eithneedle techniques is needed

Risks

Fragment embolization

Perforation

Thrombogenticity

Degradable scaffolds on non-degradable wireframe(Biostar)

Catheterization and cardiovascularinterventions 75: 72-77(2010)

MW Biostar

Zhu et al, J Biomed Biotechnol 2012

Starflex ASD device

Gore Helex ASD device

Fully degradable polymers (in experimentaluse)

Catheterization and cardiovascularinterventions (2013)

Coarctation of the aorta

Current limit of stent in infants

Material interaction

Stainless steel, nitinol

Expected numbers for biodegradableapplications

Congential market

Coronary market

Required degradation rates

Not earlier than 3-6 months for mechanicalstability

Mg stent may produce electronical currentduring

Trachea-broanchal

Thoracic surgery, biomaterials and biodegradable metals

Massimo Conti

Laval university, Canada

Metallic strut

Stratos

Matrix rib sythneths

Lung volume reduction

Nitinol

Biotechnology and bioengineering

Medical problems in the operation theatre

Eric Hesse

Germany

Trigen Sureshot

CT-Navigation

Site-specific features

Implants should not be bulky

Implants should resist cyclic load

Race between fracture healing and implantfailure

Implants should be stable and supportfracture healing

Protection of the periosteal perfusion/limitedcontact dynamic compression (LC-DCP) system

Locked plate osteosynthesis

Materials debris

Galling is a big problem for implantremoval

Osteoporotic fractures

In a future world: 需要考虑

Optimal handling

Anatomically shaped, intra OP adjustment

Minally invasive and open surgery

No implant failure

Stability and stiffness

Fespects biology

Conventional plate and locking plate/intramedullary application

Support load-bearing bones

Stimulate bone healing

Easy to remove/biodegradable

Mg implant in pediactric trauma

Expectations of bioresorable Mg implants

Retention of the fracture

Fracture healing in accordance todegradation

Good biocompatiblity

Degradation in between 18 month

Polymere

PLAs

PGAs+deren Co-polymere

Mg is historical used in children

Supracondylar humerus fracture

Childrens fracture treatment

K-wire

Screws

Intramedullary nail

***Plates are rarely used

1 generation X

WE43 vs Ti pins

Length 8mm diameter 1.5mm

2 generation X

ZX50 Mg-5Zn-0.25Ca-?Mn

Pchier K et al, JOM(2014)

3 generation Ö

ZX20 高纯Mg Zn Ca

Mg-Zn 1.5Ca0.25

下午

Challenges facing an alloy manufacturer

Robert Thornton

Magnesium elektronr

2005 开始医用镁

SynerMag

Technical challenges

Alloys selection and developments

The alloy system

Biocompatibility

Acts as a corrosion inhibitor

Tailoring the alloying system

Subtle changes in chemistry can lead toboard property

Finding the correct processing route

Thermos mechanical processing

Knowledges of how to tailor the alloysystem

Corrosion control

Contamination (Raw materials, supplierscontrols, tight specifications; manufacturing environment; processing)

New levels of process control and stability

New inspection technique

Time to market challenges

Patient benefit

Clinical trails, animal trails, developmentcosts, new manufacture cost

Concerns, challenges and potential forbiodegradable metals in clinic

Jan-Marten Seuz

Syntellix

2008 idea, founding, search for partner

2013 CE approval

2014 start of international distribution

2015 approval singapore

Magnezix CS combine stability anddegradation

Advantages

Mechanical properties significantly betterthan PLA

Application and handling similar to Ti andSS implants

Shielding stress is not expected

Histology: better

Total remodeling of the implant into bonetissue

No removal

Gtanted and pending approvals

CE, EFTA, malasiyia, iran, india

World wide 6562 devices

With the new dimensions, there will be awider range of use in orthopedics

3 years radiological results, MRI

Required properties

The mechanical properties of Mg are comparableto those of cortical bone

The ideal degradable implant

Polymers

Decomposition mainly via hydrolysis

pH: acidic

osteolysis(long term)

foreign body reaction

resorption after 2-6 years

low mechanical property

Mg

Decomposition by corrosion

Ph: alkaline

….

osteoconductivity

Low radiological artfacts(CT, X-ray, MRI)

Anti-infective effects

Challenges in biometals design for thetreatment of bone fractures

Bending by surgenon

Altering corrosion properties

Alter mechanical property

With a plate and screw, a metal-metalcontact arises.

Load-stable degradable implants

Combination of different alloys (e.g. insutures0

SLM techniques

Multi-component implant systems

Surgons have to expect a different followup situation

Remodeling might cause breaking of screwremnants visible in later follow up imaging

In some cases, temporary visible boneremodeling bones can be seen during the follow up image