rapid prototyping module assignment

De Montfort UniversityFaculty of Technology

Department of EngineeringMSc. Rapid Product Development

The role of Rapid Prototyping in surgical planning for medical

treatments

Rapid Prototyping ENGT 5132

Prof. David Wimpenny November 2010

Amani FarajStudent ID: 10374103

The role of Rapid Prototyping in surgical planning for medical treatments

Abstract

Technology is a term indicating ways used by individuals to innovate, discover and

develop. For centuries, it has been essential to strive to invent tools, machines,

materials and methods that made work and life easier. From this concept, the need

has come to invent new technologies in all areas such as communication, education,

medicine and industry.

1.There is no doubt that the tremendous advances in manufacturing

technology have had a great impact on many sectors. Given the importance

of the medicine sector, scientists, researchers and any person concerned

directly or indirectly with this area try to utilize the new technologies

provided in this field.One of the best of these technologies which has brought

a remarkable development to medicine is Rapid Prototyping (RP). Its

influence is not limited to production methods and the design of medical

devices, but also RP extends to patient treatment methods. It can be said RP

has broadened horizons to develop and improve conventional techniques

which have been used in clinical approaches. The aim of this paper is to

introduce some of the medical applications of Rapid Prototyping in surgical

planning for treatment means. It will also describe some cases in which RP

has been useful and how it has provided surgeons, doctors and patients with

possible solutions in very complex cases. In other words, how RP can make

differences in patients' lives.Table of ContentsAbstract2Contents3A

bbreviations4Table of Figures51.0 Introduction62.0 Background

63.0 Rapid Prototyping7 3.1 Definition of Rapid Prototyping

73.2 Rapid Prototyping Process Procedures 7 3.3 Rapid Prototyping

Techniques8 3.3.1 Stereolithography8 3.3.2 Fused Deposition

Modeling9 3.3.3 Three Dimensional Printing10 3.3.4 Laser

Sintering11 3.4 Selection of RP Techniques and Materials12 3.5

The Advantages of Rapid Prototyping134.0 The Role of Rapid

Prototyping in Surgical Planning For Medical Treatments…134.1 Rapid

Prototyping and The involved Technologies in the Fabrication of Medical

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Models14 4.2 Rapid Prototyping for Pre Surgical Training………….…….

……………………….………..15 4.2.1 Stereolithography for pre-surgical

planning models ................................16 4.2.2 Fused Deposition Modeling

for pre-surgical planning models...................16 4.2.3 Laser Sintering

Melting for pre-surgical planning of Cranio-Maxillofacial

surgery……………………………………………………………………………………………………………

….…..16 4.3 Rapid Prototyping for Validating Customized Implants Before

The surgery......18 4.4 Rapid Prototyping for customizing surgical aid

tools .........................................19 4.5 Disadvantages of Using Rapid

prototyping in Medical Applications …...............205.0 Conclusion ................

216.0 References227.0 Appendix24List of

FiguresFigure 1 Flow Chart for RP

procedures........................................................................8Figure 2 Principles

of SLA.............................................................................................9Figure 3

Principles of FDM

technology......................................................................10Figure 4 An

overview of the 3DP

technique..............................................................11Figure (5) an overview of

the LS process...................................................................12Figure (6)

Procedures for medical model

fabrication..................................................14Figure (7) Patient's skull

showing with a tumour......................................................15Figure (8) a

physical titanium implant on patient's

skull.............................................17Figure (9) a mandibular

implant................................................................................17Figures (10a) and

(10b) the physical implant for chin augmentation.........................18Figures

(10c) and (10D) the patient before and after the

operation..........................19Figure (11) Schematic representation of SimPlant

and a SurgiGuide…..………………....20List of TablesTable 1 Comparison between

some of RP methods ..................................................24Table 2 Brief about RP

methods..................................................................................25Abbreviations

RPRapid PrototypingCADComputer- Aided

3


DesignSTLStandard Triangulation LanguageSLA

StereolithographyFDM Fused Deposition Modeling3DP

3 Dimensional Printing LS Laser SinteringLM

Laser MeltingCAM Computer- Aided ManufacturePC

polycarbonateABS Acrylonitrile Butadiene StyrenePPSF

PolyphenylsulfoneCT Computed TomographyCBCT

Cone- Beam Computed TomographyMRI Magnetic

Resonance ImagingDICOM Digital Imaging and Communication in

Medicine2D Two Dimensions3D Three DimensionsUV

Ultraviolet1.0 IntroductionThe development of production and

industrial design processes has become linked to the recent technological

development of computer science that is used in these processes. This

development facilitates the design process and productivity in order to

optimize performance in terms of quality and speed of product delivery. All

this will eventually lead to reducing the time required for modeling and

minimizing the cost. In addition to developments in the aforementioned

related technologies and the correlation with the evolution in manufacturing

processes, intense competition in the global market has led to the invention

of new technologies and the development of existing ones in order to achieve

the maximum profit.2.0 BackgroundIt is generally agreed that there are

three possible methods of creating a part. Firstly, conservative techniques

such as casting and forging, in which there is no need to add or remove

materials. Secondly, subtractive techniques in which the part is produced by

removing unwanted materials to end with the required design. Both these

types of techniques can be considerably expensive and waste materials and

time. Thirdly, additive manufacturing (Rapid Prototyping) which, put simply,

combines parts to build a product part by part. This concept can be cost-

effective by saving the time needed to build a mould and reducing materials

wasted by removing or tooling 1. For decade, it was difficult to apply this

concept until the 1980s due to the inexistence to many factors, for instance,

appropriate materials and computer modeling programs. In the late 1980s,

linked to advances in computer software, the first system of Rapid

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Prototyping techniques was introduced by 3D System by Chuck Hull in

Valencia, California. It led to a revolution in the industrial sector1. 3.0 Rapid

Prototyping3.1 Definition of Rapid Prototyping Process A simple

description of RP Technique is that it is a process in which the desired

product is built from special materials layer by layer. Each layer, which

represents a cross section of the product, is fused by a laser on a moving

platform. After the layer is built, the platform moves down by the layer's

thickness to start fabricating the next one 2. 3.2 Rapid Prototyping

Process Procedures There are many steps which should be taken in the

RP process, some of them as preparation steps others after the complete part

has been built. These steps, shown in Figure (1), are:CAD modeling: The first

step is that a solid model for the entire part should be prepared as computer-

aided design (CAD) model with all its geometrical specifications .

1. STL generating: in this step, an STL file is created for the 3D model using

specific software such as Materialise Magics to import the 3D CAD model and

break the part surface into triangular facets.

2. Part orientation: an appropriate orientation for the model should be defined.

Many factors should be considered such as accuracy, surface finish, and

reducing supporting materials as much as possible.

3. Supports generation: supporting structures should be generated to the STL

model for overhanging features.

4. Model slicing and path tooling: The next step is slicing the model into layers

and defining the tool path to produce the model on the RP machine.

5. Prototyping production: building the model on the desired machine.

6. Post- processing: finally, the complete model may need to have the

supported structures removed and the surface polished 3.

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Figure (1) A flow chart for RP procedures 3.

3.3 Rapid Prototyping techniques

Rapid Prototyping systems can be classified according to the materials which are

used to fabricate the model. From this concept RP technologies are organized as

below:

Liquid-based systems, such as Stereolithography.

Powder-based systems, such as Selective Laser Sintering.

Solid-based systems, such as Fused Deposition Modeling 4.

3.3.1 Stereolithography (SLA/SL)

SLA as shown in Figure (2), it is an RP process in which a part is fabricating in a

container filled with a photopolymer liquid resin as cross-sectional layers. After each

layer is cured by a UV laser, it is bonded to the layer below and the platform is

dropped one layer thickness and then a sweep arm spreads another coat of resin.

This process is repeated until the completed part is formed. Supporting structures

are built during the fabrication of each layer. A wide range of materials is available

for SLA technology either

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1 .CAD modeling

2 .STL files generation

5 .Model slicing and path tooling

6 .Prototype production

7 .Post -processing

4 .Support generation

3 .Part orientation

Product Design

Final Prototype Model


from machine manufactures or materials manufactures, such as DSM and 3D

systems. These materials are based on photocurable resins, for example epoxy,

acrylic and polyurethane 5.

Figure (2) Principles of SLA 6.

3.3.2 Fused Deposition Modeling (FDM)

In this technology, each layer of the 3D part is formed by extruding a heated plastic

filament or metal wire in a heated extrusion nozzle. The nozzle is controlled by

computer-aided manufacturing software (CAM) to move in two directions vertically

and horizontally. After the molten material is deposited, it is immediately hardened.

Another head builds supporting structures which can be from materials dissolved in

water or easily removed by hand. Both heads can be in different dimensions and two

coloured materials can be used. Examples of materials used include Acrylonitrile

butadiene styrene (ABS), polycarbonate (PC) and polyphenylsulfone (PPSF) 7.

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Figure (3) Principles of FDM technology 8.

3.3.3 3 Dimensional Printing (3DP)

This process has the same principles of additive manufacturing technology. The

complete model is formed layer by layer. The machine deposits a layer of powder on

the platform, then the liquid binder supply (resin), which can be transparent or

coloured, deposits the binder on the layer of the powder as a defined cross-section

of the part. The binder bonds the layer to the one below. The machine repeats this

step until the complete product is constructed. In this process, the model is built

without supporting structures where the unused powder backs up the model and

can be recycled afterwards. After the model is left to cure in the powder, an infiltrant

can be used to improve the model’s properties. This stage depends on the planned

use of the product 9.

8


Figure (4) A overview of the 3DP technique 10.

3.3.4 Laser sintering method

In this process, the cross section of each layer is formed by using a high power laser

which selectively melts the based powder material on a powder table surface. After

the layer is built, the powder surface is lowered and another layer of powder is

applied on top of the previous one to start producing another layer. The surrounding

unfused powder supports the model; therefore, there is no need to built supporting

structures. The powder can be plastic, metal, ceramic or glass 11. If the materials used

are metals, the process is called Selective Laser Melting, (SLM) 12. Figure (5) shows

the concept of the LS apparatus.

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Figure (5) A overview for LS process 13.

3.4 Selection of RP technique and materials

Selection of an appropriate technique, which suits a specific part, can be difficult due

to the limitation of references and the availability of a wide range of techniques.

There are many factors which must be taken into account, for example, cost

(including materials and fabricating time), properties needed for the model, quality,

accuracy and surface finish. In terms of the medical applications of RP, there are

many specifications which should be taken into account. For instance, medical

materials must be biocompatible and inactive such as titanium alloys, due to the

need to implant them into the patient's body, medical models for diagnosing the

disease and understanding the surgical procedures for cancerous regions, which are

made by SLA, should be made from photosensitive resign14. Comparison between

the aforementioned RP methods can be seen in the Appendix, Table 1 and Table 215.

These tables can be used as guidelines.

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3.5 The advantages of Rapid Prototyping

It should be noted that RP technology has brought breathtaking benefits to the

world market. It can be considered as a revolution in manufacturing sector. Some of

these benefits are:

The ability to produce complex geometric products.

Saving time and money, impliedly, minimizing cost

The capability for use in many sectors such as Medicine, Education, and

Industry.

The ability to detect faults in existing products, enabling correction.

The chance to test features of the product such as function, design

specifications and accuracy.

Involvement of customers in the design process, allowing them to visualize

the complete product 16.

4.0 The role of Rapid Prototyping in surgical planning for medical

treatments

Recent years have seen the widespread use of Rapid Prototyping technology. The

impact of RP technology and related technologies such as CAD, CT, MRI and Mimics

should be grateful and appreciated. The usability of RP can be seen in many medical

fields. In addition to medical devices and instruments, RP is beneficially used in

preoperative planning, surgical aid tools, implants and tissue engineering. It can be

specifically applied to produce customized items for particular patients according to

the condition of their illness.

4.1 RP and the technologies involved in the fabrication of medical

models

In order to process information into an RP machine, there is a need for a medium to

handle the 3D model specifications "Inputs". There are many technological methods

and software packages available in addition to CAD and CAM. Some of the

technologies related to RP are:

Computed Tomography (CT): this is a medical imaging tool which applies a

tomographic technique by using an X-ray source to computationally create a

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cross-section image of the body of the patient. This technology is particularly

useful for bone imaging 17.

Cone-Beam Computed Tomography (CBCT): this uses the same technical

procedures as CT but it can be more beneficial for soft-tissue imaging and

dental applications 17.

Magnetic Resonance Imaging (MRI): this technique uses a high power

magnetic field and radio waves to generate a cross-section image. Although

it is not effective in bone imaging, in RP, MRI data for soft-tissue and CT data

for bone image can be combined to generate a complete 3D model of a

particular organ or a specific region 17.

Digital Imaging and Communication in Medicine (DICOM): this '' is a standard

for handling, storing, printing, and transmitting information in medical

imaging '' 18.

Medical imaging transferring software: in order to transfer medical image

data obtained from medical imaging technologies such as CT or MRI, accurate

and effective software is required, for instance, Mimics from Materialise NV

(Leuven, Belgium) 19. CT, CBCT and MRI produce the data of the model in a

group of 2D images with extremely small thickness and Mimics is able to

transfer image data which is a DICOM file to a STL file of the 3D model 20.

Figure (6) illustrates common RP procedures for medical model.

Figure (6) Procedures for medical model fabrication 21

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4.2 RP for pre-surgical training

Until the 1980s, surgeons had to rely on subtractive methods to create a 3D model

by using a milling machine and producing the model by removing the material from a

block. This process was adequate except for producing accurate internal and

external features. These problems were solved in the early 1990s after

Sterolithography was introduced in the late 1980s 22.

Research confirms that the use of Rapid Prototyping in the stage prior to some

complex operations which need accuracy and experience helps surgeons to have a

perceptible view of the steps of the surgery. Producing a model using RP provides an

aid to clinicians in evaluating the operation and making the appropriate decisions. As

a result, simulating and rehearsing the surgery contribute significantly to reducing

the risk to the patient's life. Furthermore, by minimizing the time needed for surgery,

impliedly, this will reduce costs 23.

4.2.1 Stereolithography for pre- surgical planning models

Normally, SLA resins are transparent or translucent. This property can be useful in

producing customized models in which surgeons can see internal features. Coloured

regions can be provided by exposing the required regions to extra UV light after

applying an anti-UV lacquer which does not pass UV light. This technique can be

used to mark vascular structures needed to be avoided during the surgery. Figure (7)

shows the use of SLA to differentiate tumour tissue from the skull bone 24 .

Figure (7) - patient skull showing tumour 25

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4.2.2 FDM and 3 DP for Pre-surgical planning

The capability to produce models from two heads in the FDM process provides the

clinicians with another solution for producing coloured parts. For example, the first

head which fabricates the part can be used to create healthy regions and the other,

which builds supporting structures, to build cancerous areas. The same capability to

produce coloured parts is afforded by the 3DP process but parts can be created with

more than two colours 24.

4.2.3 Selective Laser melting for Pre-surgical planning of Cranio-Maxillofacial

surgery

Cranio-Maxillofacial injury can be defined as damage to the skull. This disease can

result from many causes, for instance, an infected tumor, an accident (contusion) or

birth defects. The need to reconstruct the damaged area is very substantial whether

for the functional performance of the facial region or the aesthetic aspect. Any

impairment of one or both definitely has an adverse impact on the patient's life.

Rehabilitation of the deformed region needs transplantable tissues or artificial

implants to replace the defective area. If transplanted tissues are available then they

will be the first choice. The patient's bone can be used in reconstructing the

damaged area in the maxillofacial region. However, this choice incurs some risks,

especially for the donor, thus artificial implants from biocompatible materials can be

made to achieve the physical and aesthetic function of the organ 30.In the case of

replacing a damaged area, there are radical required properties which should be

obtainable in the implant materials such as biocompatibility, inactivity and lightness.

Titanium or cobalt-chrome alloys are two of the most compatible materials used to

make implants. Figure (8) shows a model of a patient's skull with an implant printed

on it. Using a SLM apparatus, two implants were produced prior to the surgery for a

patient who had a cranial deformity. The first model for the implant was produced

using polyamide to use as communication tool which provided surgeons, engineers

and the patient with a full understanding of the surgical procedures. The second one

was built from titanium alloy to replace the deformed area 26.

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Figure (8) a physical titanium implant on patient's skeleton 26

Figure (9) shows a mandibular implant for a twenty-four-year old man who had

suffered from hemifacial microsomia, which is a birth defect. In this case, there were

specific characteristics which were necessary in the implant material. The implanted

part had to prevent development of bacteria and be light weight to conform to

functional properties. As for the cranial implant, two models were produced by using

SLM. The first was made of polyamide for inspection procedures and the real model

was made of a titanium alloy. Generally, by using RP methods, surgeons become

satisfactorily able to diagnose the disease and then determine treatment method or

how to conduct the surgery 26.

Figure (9) A mandibular implant 26

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4.3 Rapid Prototyping for validating customized implants before

surgery

In addition to the possibility to simulating the surgery, rehearsing it and how it can

be conducted, RP has enabled surgeons to examine the compatibility of implants

which are needed to replace defective areas and obtain the desired geometric

specifications before the surgery.

In a case study of a woman who needed to augment the size of her chin, an implant

had to be built such that the inner surface must matched the outer surface of her

real chin and the outer surface of the implant had be suitable from an aesthetic

standpoint. In this case, it was necessary to produce a physical model for the

mandible using CT data and exporting it to an RP machine. After the mandible had

been built using the RP technique, the geometric characteristics of the inner surface

of the implant were obtained by using reverse engineering software. The outer

surface was determined by using Magics software from Materialise and a cadaver

mandible, Figure (10a) shows the 3D model of the implant. By gathering all the

geometrical data, a model for the implant was produced and its compatibility to the

model of the mandible examined by fitting it to the mandible model as Figure (10b)

shows. This implant was used to produce positive pattern to make a silicon rubber

mould where a titanium implant was fabricated. Figure (10c) and Figure (10d) shows

the patient before and after the surgery 27.

Figure (10a) 3D implant model Figure (10b) the physical implant for chin augmentation 27.

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Figure (10c) the patient before the surgery figure (10-D) the patient after the surgery 27

4.4 Rapid Prototyping for customizing surgical aid tools

Since it has become common to use RP in simulating surgery, as previously

mentioned, keeping in mind its tremendous influence, the optimal utility of it has

become the target of specialists in this area. In addition in inspecting implants and

planning surgery, RP is used to fabricate surgical tools in order to facilitate the

surgery.

This has become widely used in dental treatments where it has become possible to

produce assisting tools to facilitate implant treatments. Beside its capability to

fabricate crowns, bridges and artificial teeth, it can be used to produce surgical drill

guides which help with implant placement process by using special software such as

SimPlant from Materialise. SimPlant is software which uses CT data of the patient's

bone as an input to produce a 3D visualizing model of patient's mandible and create

implant planning with precise positions for implants. SimPlant provides surgeons

with all the important information such as bone density, bite force and sinus graft

volumes. Then, using Stereolithography, customized drill guides are manufactured to

place on the jawbone for accurate drilling and to avoid both nerves and

misplacement as Figure (11) shown 28.

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Figure (11) Schematic representation of SimPlant and a SurgiGuide 29

4.5 Disadvantages of using RP for medical applications

Although RP has brought radical solutions to critical situations for many patients, in

some cases saving their lives, RP, as any other technology, has its own disadvantages

which can be briefly listed as:

It is costly process. It may be inappropriate to state this process is costly

when the result of it is to save or improve life. This cost is a result of the low

number of machines and cost of materials used to produce the part.

Optimistically, in time this cost will reduce.

In order to fabricate a medical model, special properties are required to be

provided such as biocompatibility and sterility. The available materials do not

always provide the desired degrees of these specifications. Moreover,

mechanical characteristics are poor to some extent, RP models are

considerably brittle and may not be able to shoulder a heavy load.

It is not suitable in an emergency situation when a model is needed urgently.

This technology may be appreciated by doctors and surgeons if it is applied to

long term pre-surgical planning.

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Because of linking to others technologies from different disciplines such as

engineering, computer sciences and medicine; the RP process needs an

expert technician with sufficient experience in these disciplines. This

technician is unlikely to be available to accomplish all the required tasks of

producing a model, operating and maintaining the machine for RP medical

applications 30.

5.0 Conclusion

As mentioned before, RP has helped patients in finding solutions for complex

problems had adverse effects on their lives. To evaluate the efficiency of RP, it

suffices to indicate the differences which it has brought about in patients' lives. As

can be concluded from the cases in this paper, RP has achieved satisfactory results in

terms of the aesthetic and functional properties of the implants. RP might be

considered a costly technique and it is not affordable for every patient, but as with

any new technology, its cost might drop gradually from its level.

Rapid Prototyping has provided surgeons with chances to rehearse surgeries,

effectively diagnose diseases and to conduct surgeries confidently. As consequences,

they were able to reduce the risk to the patients and reduce the time of operations.

To sum up, regardless of the disadvantages of Rapid Prototyping in medical

applications; the lack of biocompatible materials, cost, and experience requirements,

it can be said that Rapid Prototyping has made a quantum leap in the medical sector

and many promising steps are planned.

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6.0 References

1 Venuvinod, P.K and Weiyin M. Rapid Prototyping, Laser-Based and other technologies, USA, Kluwer Academic Publishers, 2004, p xi

2 Wimpenny, D, Basic principles of layer manufacturing, Rapid Product Development, De Montfort University, Leicester, 2010.

3 Venuvinod, P.K, P.K and Weiyin M. Rapid Prototyping, Laser-Based and other technologies, USA: Kluwer Academic Publishers, 2004, p 135

4 Hopkinson, N, Hague, R.J.M, Dickens, P.M. (editors) Rapid manufacturing an industrial revolution for the digital age, UK, John Wiley and Sons, 2006,p.57


6 Princeton .edu available online at www.princeton.edu/~ cml/assets/images/mems02


8 custompartnet.com available online at www.custompartnet.com/wu/images/rapid-prototyping/fdm.png [accessed 23/10/2010]


10 custompartnet.com available online at www.custompartnet.com/wu/images/rapid-prototyping/3dp.png [accessed 23/10/2010]


12 Wikipedia, Selective Laser Sintering [online] available from http://en.wikipedia.org/wiki/Selective_laser_sintering [accessed 25/10/2010]

13 custompartnet.com available online www.custompartnet.com/wu/images/rapid-prototyping/sls.png [accessed 23/10/2010]

14 Milovanovic, J. and Trajanovic M, Medical applications of Rapid Prototyping, FACTA UNIVERSITATIS, 5, 1, 2007, pp 79-85.

15 Arpetch RP services Selection Guides available online at www.arptech.com.au/srvcompare.htm [ accessed 5/11/2010]

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16 Wimpenny, D. Basic principles of layer manufacturing, Rapid Product Development, De Montfort University, Leicester, 2010

17 Wohlers, T, Wohlers Report 2008, State of the industry, USA, Wohlers Associates, 2008, p172.

18 Digital Imaging and Communications in Medicine, available online at en.wikipedia.org/wiki/DICOM [accessed 27/10/2010]

19 Gibson, I (editor), Advanced manufacturing technology for medical applications, England, John Wiley and Sons, 2005, pp 70-80.

20 Drstvensek, I Hren, N.I. , Strojnik T , applications of Rapid Prototyping in cranio- maxillofacial surgery procedures, International Journal of Biology and Biomedical Engineering, 1, 2, 2008.

21 Rapid Prototyping Journal, available online at www.Emeraldinsight.com/Journal.

22 Gibson, I (editor), Advanced manufacturing technology for medical applications, England, John Wiley and Sons, 2005, p22.

23 Hopkinson, N, Hague, R.J.M, Dickens, P.M. (editors) Rapid manufacturing an industrial revolution for the digital age, UK, John Wiley and Sons, 2006,pp.(177-178)

24 Gibson, I (editor), Advanced manufacturing technology for medical applications, England, John Wiley and Sons, 2005, pp 6-7.

25 Protomed.net available online at www.protomed.net/planning/tumor.html

26 Drstvensek, I Hren, N.I. , Strojnik T , applications of Rapid Prototyping in cranio- maxillofacial surgery procedures, International Journal of Biology and Biomedical Engineering, 1, 2, 2008.

27 Singare S, Dichen L and Bingheng L, customized design and manufacturing of chin implant based on Rapid Prototyping, Rapid Prototyping Journal, 11, 2, 2005, pp. 113-188

28 Gibson, I (editor), Advanced manufacturing technology for medical applications, England, John Wiley and Sons, 2005, p 92-94.

29 Materialise Dental available online at www.materialise.com/materialise/view/en/2970681-Selected+cases.html

30 Gibson, I (editor), Advanced manufacturing technology for medical applications, England, John Wiley and Sons, 2005, p 13-14.

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7.0 Appendix

FDM SLA SLS CNC 3DP

Relative Cost ( Small to medium size parts )

Relative Cost ( Medium to large size parts)

Accuracy

Functional Prototypes

Presentation Prototypes

Fine & Crisp Feature Detailing

Strength

Material Selection Range

Typical Lead time

Parts with snap fit features

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POOR AVERAGE BEST N/A

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http://www.arptech.com.au/services/slsrv.htm

http://www.arptech.com.au/services/slasrv.htm

http://www.arptech.com.au/services/fdmsrv.htm


Water, Chemical, Heat resistance

Metal prototypes direct from machine

Elastomer, Flexible Rubber like parts

Master Models for Tooling

Table (1) Comparison between some RP methods15

FDM SLA SLS CNC 3DP

Brief summary of

the RP Technologie

s

Good combination of strength and surface finish at affordable price and lead time.

Excellent surface finish suitable for presentation, master models and light functional testing.

Range of materials available, soft like rubber to strong like metal. SLS Nylon suitable for snap and living hinge features

Use when mechanical properties can not be compromised with any additive RP process.

Suitable for general purpose parts for initial design stage with a quick delivery.

Table (2) Brief about RP methods15

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http://www.arptech.com.au/services/slasrv.htm

http://www.arptech.com.au/services/fdmsrv.htm

rapid prototyping module assignment

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