F R A U N H O F E R I N S T I T U T E F O R L A S E R T E C H N O L O G Y I LT

DQS certified by

DIN EN ISO 9001

Reg.-No.: DE-69572-01

Fraunhofer-Institut

für Lasertechnik ILT

Director

Prof. Reinhart Poprawe

Steinbachstraße 15

52074 Aachen, Germany

Phone +49 241 8906-0

Fax +49 241 8906-121

info@ilt.fraunhofer.de

www.ilt.fraunhofer.de

Fraunhofer Institute for Laser Technology ILT

The Fraunhofer Institute for Laser Technology ILT is worldwide

one of the most important development and contract research

institutes of its specific field. The activities cover a wide range

of areas such as the development of new laser beam sources

and components, precise laser based metrology, testing

technology and industrial laser processes. This includes laser

cutting, caving, drilling, welding and soldering as well as

surface treatment, micro processing and rapid manufacturing.

Furthermore, the Fraunhofer ILT is engaged in laser plant

technology, process control, modeling as well as in the

entire system technology. We offer feasibility studies,

process qualification and laser integration in customer

specific manufacturing lines. The Fraunhofer ILT is part

of the Fraunhofer-Gesellschaft.

Subject to alterations in specifications and other technical information. 05/2018.

SELECTIVE LASER MELTING FOR MEDICAL IMPLANTS

Individual and Functional

In SLM, component parts are built layer by layer from a fine

powder that is melted by laser radiation according to a CAD

model. Since it manufactures parts without tools and does

so in layers, SLM lends itself well to cost-effective individual

fabrication of complex geometries. Tailor-made implants can

be designed on the computer directly from medical image

data (CT, MRT) for a patient and subsequently manufactured

with SLM cost-effectively. If needed, these patient-specific

implants can be provided with additional functions that cannot

be achieved with conventional manufacturing methods, or

only at a very high cost. On the one hand, when an implant’s

pore structures are carefully defined, for example, technicians

can improve how well the implant is integrated into the tissue

(osseointegration) and how well new tissue (vascularization) is

supplied to the implant. On the other, SLM enables technicians

to set optimal mechanical properties that are desirable for the

particular patient and site of implantation.

In particular, with resorbable implants, defined pore structures

are a decisive advantage compared to non-porous implants.

The total volume that needs to dissolve can be reduced signi-

ficantly and an effective transport of the dissolved products

can be guaranteed by a complete vascularization of the implant.

At the same time, the bone can form inside the implant so

that the implant is strengthened by new autologous bone

while it decomposes.

Medical Implants Manufactured with SLM

SLM is already being used commercially with many metallic

biomaterials (e.g. titanium alloys, cobalt-chromium alloys

or stainless steel). For applications in medical technology,

the Fraunhofer ILT has already put this process into practice

in cooperation with partners from medical and industrial

companies for the individual series production of coronal

caps and bridges in the dental industry, for joint replacement

(e.g., hips, knees) in orthopedic surgery and for bone replace-

ment in dental, oral and maxillo-facial surgery. In addition

to individual implants, highly specialized surgical instruments

and spinal fusion cages with enhanced functions can also

be manufactured with SLM. These SLM components fulfill all

the requirements of the corresponding regulatory standards

upon mechanical properties and biocompatibility.

The Fraunhofer ILT also offers promising solutions to current

research questions. As an example, we were able to success-

fully test resorbable bone replacement implants that have

interconnected pore structures – made on the basis of a

polylactide-calcium phosphate composite; they were used in

small animal experiments for an area of the skull under low

biomechanical stress. At the same time, we are researching

the use of the technology for resorbable implants made on the

basis of resorbable magnesium alloys for higher load-bearing

areas.

From Idea to Product

The Fraunhofer ILT developed the SLM process in the middle

of the nineties, and since then has constantly refined it in

close cooperation with leading industry companies and

research institutions while taking the whole process chain

into consideration. Thanks to our expertise and many years

of experience, our experts can assist you individually from the

very first idea, through feasibility studies, process and system

development all the way to implementing the results into your

production chain. You can fall back upon our comprehensive

range of equipment, consisting of various commercial systems

and highly flexible laboratory plants, but also upon our know-

how in the area of laser beam source and optics development.

Thanks to our close cooperation with other Fraunhofer Institutes,

the FH Aachen University of Applied Sciences, the University

Hospital RWTH Aachen and the RWTH Aachen University,

you can also profit from the bundled competence this location,

Aachen, offers in the sector of additive manufacturing.

Contact Partners

Dipl.-Phys. Lucas Jauer

Telephone +49 241 8906-360

lucas.jauer@ilt.fraunhofer.de

Dr. Sebastian Bremen

Telephone +49 241 8906-301

sebastian.bremen@ilt.fraunhofer.de

SELECTIVE LASER MELTING FOR MEDICAL IMPLANTSIf individually adapted bone and joint replacements or medical implants had greater functionality,

e.g., through integrated and defined pore structures, physicians could significantly improve medical care. The

additive manufacturing process, Selective Laser Melting is particularly suitable to manufacture such complex

and individualized implants.

Trends and Challenges in Medical Technology

Both demographic change and the need for ever improving

medical care have placed new challenges upon healthcare

research. In particular, personalized medical technology is

considered one of the most promising fields of the future.

By taking the individual medical needs of the patient into

consideration, e.g. when planning an operation or designing

the implant, physicans can improve minimally invasive surgery,

thereby guaranteeing the patient optimal medical care. On

the one hand, this can considerably increase a patient’s sense

of well-being, and, on the other, reduce the costs for the

health care system and the economy systematically.

The use of resorbable implants as bone replacements is also

setting new standards. These implants dissolve in the bones

of the patient and are successively replaced by the body’s

own bone. This way, implants can be created that “grow” in

children as they grow, thus making it unnecessary to remove

an implant after bones have healed, or for an implant to

remain in the body permanently.

32

Front page: individualized cheek bone implant

with interconnected porous structure.

1 Individualized coronal caps and bridges

for dental applications.

2 µ-SLM scaffold (strut thickness approx. 60 µm).

1

3 Individualized cranial implant

with interconnected porous structure.

4 Scaffolds out of biodegradable

magnesium alloy.

5 Individualized acetabular cup.

54