- 3D printing has applications in surgery such as creating anatomical models for surgical planning, education, and custom implants and prosthetics. - There are various 3D printing methods like extrusion, light polymerization, and powder bed that use different materials like resins, metals, plastics depending on the desired properties and regulations. - 3D printing allows for personalized, patient-specific models and implants to be created cost-effectively from medical imaging data for improved surgical outcomes.

1. 3D PRINTING IN SURGERY
ZAHID IQBAL MIR

2. HISTORY OF 3D PRINTING
Hideo Kodama - first rapid
prototyping machines - created
parts using a resin that could be
polymerized by UV light (1981).
https://doi.org/10.1016/B978-0-12-803917-5.00001-8

3. HISTORY OF 3D PRINTING
Charles W Hull - “the inventor of 3D
printing” for creating and
commercializing stereolithography
(SLA) and the .stl format – Patent
(1986).
• 3D Systems - First commercial SLA
printer (1988).
https://doi.org/10.1016/B978-0-12-803917-5.00001-8

4. Carl Deckard - Selective laser sintering
(SLS) process.
• SLS - Selective solidification of powder
using a laser beam.
• Desktop Manufacturing Corporation (DTM
Corp) - 3D Systems (1992).
• Sinterstation 2000 – SLS ( 1993).
HISTORY OF 3D PRINTING
https://doi.org/10.1016/B978-0-12-803917-5.00001-8

5. S. Scott and Lisa Crump – Stratasys
• Patent for a form of rapid prototyping
called fused deposition modeling (FDM)
- 1989
• Stratasys - developed thermoplastic
and printer systems for 3D printing
HISTORY OF 3D PRINTING
https://doi.org/10.1016/B978-0-12-803917-5.00001-8

6. TRADITIONAL MANUFACTURING VS 3D
• Traditional manufacturing "subtractive" technique -
milling, injection molding, carving or using a
computer numerical control router
• 3D printing / rapid prototyping / additive
manufacturing “additive” - successive layers created
and stacked, digitally designed from a 3D image
source file.

7. https://doi.org/10.1016/j.stlm.2023.100110

8. 3D PRINTING METHODOLOGY

9. IMAGE CAPTURE & PROCESSING
• Mc methodology - medical imaging ( high resolution
CT, USG or MRI - intracorporeal structures
• DICOM format - handling, storing, printing, and
transmitting information in medical imaging.
• Sequential series of tomogram slices - discrete
volumetric 3D representation

10. IMAGE CAPTURE & PROCESSING
For external surfaces and extracorporeal structures - 3D
scanners (contact or non-contact).
Contact scanners : not common place for medical or
surgical applications.
Non-contact scanners : emit a form of radiation or light
and detect its reflection or radiation. Mc - time of flight
laser scanner (measure, distance of 10,000-100,000
points every second)

11. 11
3D Data source file
3D Mesh
Compatible format
.stl format
Compatible 3D
printing platform
IMAGE CAPTURE & PROCESSING
• After acquisition - open source
software used to produce a 3D mesh, -
manipulated, converted and exported
in a format compatible with 3D printers.
• Computer aided design (CAD)
software - manipulate, resize and
render a component of the original file
• Exported to 3D printing platform.

12. Conventional medical imaging - digital
3D representation of an intracorporeal
structure.
Time-of-flight laser scanning - external
surface features.
Raw image file can be manipulated
post acquisition by CAD - 3D printing
platform for rapid prototyping.

13. PRINTING
• Various methods for the sequential deposition of
materials.
• Core of concept is the ablity to manipulate the
printable substrate, from a semi-liquid or powder
state, to a solid or semi-solid that can then be
stacked in a controllable manner.

14. EXTRUSION
• Most familiar to the hobbyist or small-scale 3D
printing.
• Fused deposition modeling (FDM) uses a heated
semi-solid thermoplastic that is forced through an
extrusion nozzle at a controlled rate, whilst being
moved on a 3D armature. – Substrate cools to
become solid - sequential stacking.
• Hand-held "pen" - free form of variant of 3D printing

15. EXTRUSION
• Thermoplastics that are used are acrylonitrile
butadiene styrene (ABS), polylactic acid (PLA),
polyamide and polycarbonate etc.
• Suitable for producing teaching models and
implants, but not for printing of cell based
scaffolds due to the high temperatures (over
100°C) involved.

16. LIGHT POLYMERISATION
• Stereolithography (STL) : Laser light - vat of liquid
photopolymer resin ( monomer and oligomer
subunits and photoinitiator molecules ) - UV light -
chain growth polymerization and cross-linking.
• Polyjet 3D printing - similar technology to ink jet
printing, with multiple colours of photopolymer
instantly cured after printing.

17. • Speed of cure and density of cross-linking can
also be manipulated through composition of resin.
• Initial layer is photocured - Subsequent layers are
printed - Final 3D form.
• Due to the cytoxicity of substrates - not usually
suitable for cell-based constructs.
LIGHT POLYMERISATION

18. POWDER BED
• Selective laser sintering (SLS) : Based upon
powder rather than liquid.
• Pulsed laser selectively fuses small particles
of plastic, metal, ceramic or glass to produce
an additive 3D form.

19. • Does not require additional physical supports to aid
printing of overhanging designs – Unsintered
material
• Selective laser melting - takes substrate material to
its melting point, rather than lower temperature
required for sintering.
POWDER BED

20. • FDM- based upon an armature that
can be controlled in three dimensions.
• STL - 3D structure from liquid resin
• SLS - laser energy to fuse a powder
substrate in a similar manner.
• Polyjet printing - Ink jet technology
instantly cured after printing.

21. • Majority of applications of 3D printing in surgery
are for teaching, implantation or prostheses – do
not require biological components (cells, matrix
proteins or cytokines).
• A printing substrate that has biological
components – “boink”
BIOINKS & BIOPRINTING

22. • Different cell types used as a component of boink,
including fibroblasts, mesenchymal stem cells,
hepatocytes, neuronal cells.
• To allow cellular metabolism within the scaffold –
Hydrogels (alginate, agarose, gelatin, collagen,
fibrin, hyaluronic acid, silk and chitosan ;
polyethylene glycol and pluronic gels ) – ECM
• Vascular like constructs – cellular survival
BIOINKS

23. IDEAL BIOINK

24. • Variant of extrusion printing - designed to dispense the
materials in layered lines onto stage using single or
multiple syringes.
• Higher viscosity substrate is used that can be extruded but
will retain its structural integrity at biological temperatures
without the need for an immediate curing.
• Three methods of direct writing : pneumatic, mechanical,
and a pneumatic-mechanical hybrid.
DIRECT WRITE BIOPRINTING

25. • Bioinks contain biological components within a
gel matrix - viscous enough to extrude and
stack layers - 3D form.
• Direct write bioprinting - extrusion based
system, either mechanical or pneumatic, to
create a 3D structure.
• Boink undergoes a secondary step to produce
a stabilized final form.

26. • Variant of extrusion printing - designed to dispense the
materials in layered lines onto stage using single or
multiple syringes.
• Higher viscosity substrate is used that can be extruded but
will retain its structural integrity at biological temperatures
without the need for an immediate curing.
• Three methods of direct writing : pneumatic, mechanical,
and a pneumatic-mechanical hybrid.
DIRECT WRITE BIOPRINTING

28. Black Panther: Wakanda
Forever (2022)
Black Panther” (2018)
3D printed costumes

29. APPLICATIONS N SURGERY
Anatomic models
• Surgical teaching and training
• Patient information
• Preoperative planning
Surgical instrumentation and guides.
Implants, prostheses, splints, and external
fixators

30. Surgical teaching and training
• Models based upon unique pathology from patient
imaging studies.
• Rapid prototyping is an evolving technology -
revolutionize medical education.
• Personalized, patient-specific, model
APPLICATIONS N SURGERY

31. • Patient-specific 3D models of portal and hepatic
venous anatomy - SLS at a cost < than $100
• Complex intracranial aneurysms, cleft lip-palates,
free flaps and renal vasculature - STL or polyjet
• Soft tissues can be mimicked using FDM, STL and
SLS, hard tissues such as the bicortical calvarial
bone from plaster using powder bed technique
APPLICATIONS N SURGERY

32. Patient information
• Educating patients about disease and deformity
• Compare it with model of postoperative outcome -
realistically manage their expectations
3D Polyjet printed model of kidney tumor - improve
understanding of kidney physiology, anatomy, tumor
characteristics and planned surgery
APPLICATIONS N SURGERY

33. Pre operative planning
3D-printed patient-specific models
Anticipate intraoperative difficulties, selection of
optimal surgical approach and need for specific
equipment.
APPLICATIONS N SURGERY

34. • Craniofacial, skull base and cervical spine
reconstruction.
• Mapping of congenital heart defects and
tracheobronchial anomalies.
• Modelling of aortic dissection, partial nephrectomy,
reconstruction of frontal sinus defects , treatment of
wounds, liver transplantation
APPLICATIONS N SURGERY

35. Splenic artery aneurysm Left adrenal gland tumor and its
relationship with kidney
Material Jetting printer (Objet 260 Connex 3—Stratasys)

36. 3D printed model of kidney with a small cortical tumor of the
lower pole (black) and a parapelvic cyst (green) made of
plaster
Binder Jetting printer (Projet 460 Plus - 3D Systems)

37. Surgical simulation with daVinci Surgical Robot
3D printed model of a splenic
artery aneurysm - robotic
aneurysmectomy prior to surgery.
Simulated robotic end-to-end arterial
anastomosis

38. APPLICATIONS IN SURGERY
Implants
Synthetic implants - craniomaxillofacial reconstruction
and orthopedics.
• Vertebral, hip, pelvis, and mandibular implants ( 3D-
printed plastic and titanium implants)
• Material properties, bioactivity, porosity, and shape of
synthetic grafts - controlled and customized

39. APPLICATIONS IN SURGERY
Implants
Bioprinting -
• Biologic scaffolds - alternative to autologous tissue
grafting or microvascular tissue flap transfer.
• Bone tissue engineering - alternatives to inorganic
implants by using biocompatible scaffold materials
and autologous cells.

40. APPLICATIONS IN SURGERY
• Soft tissue structures have also been
developed in vitro including cell-laden scaffolds
to replace heart valves
• Cartilage scaffolds - ear , nose reconstruction,
and skin composites

41. • Scaffold based approach relies on temporary scaffolds to
facilitate cellular attachment, metabolism and proliferation,
followed by cellular secretion of extracellular matrix to
remodel the surrounding environment
• Degradation of the printed scaffold over time, and
replacement by autologous tissues
• Complications with permanent scaffolds such as implant
extrusion or infection may be avoided.
APPLICATIONS IN SURGERY

42. APPLICATIONS IN SURGERY
Implants
Prosthesis
• Rapid development of additive manufacturing in
rehabilitation medicine.
• Artificial ears, noses, eyes, hand and limbs can be
modelled on unaffected contralateral anatomy

43. Alien' boy, Xiao Yu gets new skull in pioneering 3D printing surgery
Doctor Bao Nan (Shanghai Children’s Medical Center) : "Thanks to 3D-
printing technology, we were able to make a model of the patient’s skull,
which in turn allowed us to make a detailed surgical plan beforehand.
"We also measured the faces of the patient’s parents so we could design
his new face with family features."

44. • Patient specific models can be created from
DICOM data using 3.D printing to allow spatial
appreciation of complex structures for teaching
and patient education.
• Operative planning may improve efficiency.
• Custom made implants - replace the need for
autologous donor tissues.
• Low cost prosthesis

45. PATIENT SPECIFIC 3D SOLUTION

46. HELPING IMPROVE OUTCOME

47. HAND HELD 3D PRINTER
• Covers wounds with a
uniform sheet of
biomaterial, stripe by
stripe
• Bioink - mesenchymal
stroma cells (MSCs)
University of Toronto Engineering and
Sunny Brook Hospital

48. VSP is a very
viable method
that saves
time and cost,
making
surgery more
efficient.

50. Virtual surgical planning VSP - segmentation and mandible
reconstruction.

51. VSP − fibula cutting guide generation. (a) Fibula bone segmentation
with the placement of fibula planes. (b) Generation of fibula cutting guide.
(c)Fibula cutting guide in STL format (d) 3D printed fibula cutting guide
using PLA materials. (e)3D printed reconstructed mandible. (f)3D printer.

52. Intra-operative photos (a)Fibula cutting guide fixed on to the fibula (b)Fitting of fibula
cutting guide at the anterior and lateral aspect of the fibula. (c)Osteotomy cuts made and
fibula bone is cut into 3 segments. (d) Miniplates fixed onto the fibula segments. Pedicles are
still attached at this moment. (e)The main tumour was resected. (f)Fibula segments were
fixed onto the native mandible to form neomandible

53. Clinical photos
(a)Pre-operative facial
appearance.
(b)1-month postoperative
facial appearance.
(c)preop orthopantomogram
(d)1-month postoperative
orthopantomogram.

54. REGULATIONS
• In US, the Food and Drug Administration (FDA) classifies
devices based on risk and the level of control necessary
to assure safety and efficacy
• Class I devices - low risk ; Class III ( implants ) - high-
risk and require premarket approval
• Each processes of 3DP - image capture and processing,
material selection, printing, and post-printing finishing,
validating and testing, may require a form of approval.

55. REGULATIONS
• For implants, the International Organization of
Standards (ISO) has published a set of standards for
evaluating the biocompatibility of materials used in the
manufacture of medical devices, collectively termed
ISO 10993.

56. REGULATIONS
• Sterility is fundamental to minimizing risk of infection
associated with implantable medical devices.
• Sterility assurance level (SAL) - probability of a single
unit being non-sterile after it has been subjected to
sterilization
• Same regulatory requirements as non-3D printed
devices.

57. • Sooner or later even the creation of complete bodies
will be possible - bioethical issues
ETHICAL ISSUES
This does not only refer to
increasing lifespan with new
AM parts: might it be possible
for people to be re-born, by
printing the complete body of a
dead person? Now, with AM,
dead bodies can become just
another reproducible object,
like a commodity

58. • Nevertheless, as the technology is being developed, it will
be necessary to deal with it by applying new laws.
• Use of high-quality 3D printers should be limited to
industry, hospitals
• DICOM images should only be available to doctors and
patients (and on occasion to researchers for research
purposes)
ETHICAL ISSUES

59. • Surgical planning prototypes - chance to
practice before surgery. ( issues - bad
printing properties, high hardness )
• Teaching and training
• Life expectancy will increase ( fewer
illnesses or faster healing and regeneration )
GOOD ABOUT 3DP ?

60. REFERENCES
REFRENCES

61. KEY POINTS
Conventional medical imaging can be used to
transfer unique patient data to 3D modeling
software, - 3DP
3D printing methodologies are selected based upon
the design for the object that is to be printed and the
materials involved.
Substrates for 3D printing can be specifically
tailored to fulfill to optimum design requirements,
such as strength, flexibility and biocompatibility.

62. KEY POINTS
• Light-activated photopolymers, ceramics, metals,
thermoplastics, glass and natural polymers such as
alginate, gelatin, collagen, fibrin, hyaluronic acid,
silk and chitosan have all been used for 3D printing.
• Boinks contain living cells and are usually based
upon water-laden hydrogel structures - replace
autologous tissues in the future.

63. KEY POINTS
• Low-cost prosthesis
• Implantable devices require strict regulation - quality
assurance and testing.
• Same regulatory requirements as non-3D printed
devices.
• Opportunity to revolutionize surgery, and make what
once where cost-limited technologies available to
all.