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Anatoliy Popovich, Vadim Sufiiarov, Igor Polozov, et al.

sion surgery 10–15 years after the first implantation. Selective Laser Sintering (SLS) from polyamide po-
Aseptic instability and paraprosthetic osteolysis are wder using a 3D Systems Sinterstation HiQ+HS ma-
considered to be the main reasons for the loosening of chine. After making a polyamide model of the pa-
implants [14] . tient’s bone, the design of the implant configuration
The most frequent method of an unsteady implant was carried out using CAD-software. Owing to severe
replacement is the installation of acetabular compo- deformations of the hip bone, the physical model of
nents with press-fit fixation in the presence of un- the implant was made out of polymer clay, taking into
harmed support bones [15−17] . Three-flank acetabular account anatomical features of the patient. The im-
systems are modeled based on computed tomography plant was 3D-scanned using a Faro Platinum Arm
(CT) data of the patient, designing a 3D-model of pa- scanner to obtain a CAD-file of the implant. The con-
tient’s hip bones considering bone defects, and allow- figuration of the implant was further improved using
ing angles of dimensional orientation of the acetabular CAD-software; in particular, a partial texturing of the
component. implant surface has been done.
Titanium alloys—Ti-6Al-4V in particular—are wi- Ti-6Al-4V Grade 5 powder was used as the initial
dely used in different industries. One of the applica- material for manufacturing the metal implant, pro-
tion of Ti-6Al-4V alloys is the manufacturing of med- duced by plasma atomization. The particles have a
ical implants due to its high biocompatibility and a spherical form without any defects in the form of sa-
combination of mechanical properties [18−20] . Since SLM tellites (Figure 1) with the following particle size dis-
technology allows the manufacturing of near net- tribution: d 10 = 27 µm; d 50 = 47 µm; d 90 = 76 µm. The
shape parts with complex geometry, it is possible to metal implant was manufactured using SLM Solutions
make custom-made implants for each specific patient SLM 280HL machine with the parameters set provid-
while also texturing the implant’s surface with a lattice ing the relative density of about 99.9% and described
structure for better osseointegration [21,22] . There have [26,27]
been several attempts to manufacture implants via in other works . The build accuracy of the manu-
SLM technology from titanium alloys using Ti-6Al-4V, factured implant is about 200 µm. A schematic se-
CoCr alloys [23, 24] , as well as using Ti-Ta alloy powder, quence of operations used to produce a titanium hip
which is promising for medical applications [25] . Ano- implant by AM is presented in Figure 2.
ther metal additive manufacturing technique for pro- Microstructure studies were performed using a Le-
ducing complex parts from titanium alloy powders is ica DMI 5000 light microscope. Mechanical tests were
Electron Beam Melting (EBM), which uses electron carried out on Zwick/Roell – Z100 machine using sta-
beam energy for melting metal powder layer-by-layer ndard samples manufactured by SLM and then mac-
in vacuum [23] ; a promising technology for manufac- hined to the specific size according to ASTM E8/E8M.
turing individual implants from titanium alloys. Usu- Three specimens were used for each test point. An-
ally, patient’s anatomical data is reconstructed in 3D nealing was carried out using a vacuum furnace, ALD
−4
−3
and used for geometric modelling of implants. MonoTherm in a vacuum with a pressure of 10 –10
In this paper, we demonstrate the possibility of mbar.
producing individual acetabular revision systems to
carry out a revised endoprosthesis replacement of a
hip implant made of Ti-6Al-4V alloy by using AM
and data of the patient’s bone configuration acquired
by CT. CT-data is used for 3D printing a polymer
model of the patient’s deformed bone, creating a pro-
totype of the implant for modeling the surgery process.
The final model of the part is used for manufacturing
the hip implant from Ti-6Al-4V alloy powder by SLM.
2. Materials and Methods
(A) (B)
CT-data of the patient’s hip bone structure in DICOM Figure 1. SEM images of Ti-6Al-4V powder particles, pro-
file-format was used to make a physical model of the duced by plasma atomization with (A) X200 and (B) X1000
patient’s hip bone, which was then manufactured via magnification.

International Journal of Bioprinting (2016)–Volume 2, Issue 2 79