The Study of Mandible Morphology towards Implant Design for the

South African Population

Presenter: Sven DelportCollaborator: Johan van der Merwe

IntroductionTechnimark:

• 1996

• Product development

– Concept

– Prototyping

– Testing

– Manufacturing

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

1

Introduction

Energade Off-centre Nozzle Cap

Addis Comfi-Grip Range

Lawn Star Edge Trimmer

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

2

IntroductionMedical Device Design:

• 2015

• Implant product development

• Patient-specific

– 3D anatomical models

– Implant design

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

3

Case StudyIntroduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

• October 2015

• CRPM at the CUT

4

Case StudyIntroduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

5

Case StudyIntroduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

3-matic

• Symmetry did not work

• Mandible fitment

• Export point cloud

SolidWorks

• Parametric modelling

• Export STL

Surgeon

• Feedback

• Apply changes

6

Morphology Study• Bigger pictureIntroduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

Mandible Morphology

Study

Statistical Shape

Modelling

Patient-specific Implant Design

7

Co

Morphology Study• Morphology

– Study of form and structure

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

*Reproduced from Bayome et al. (2013)

MSP

FHP

Med Co Lat Co

Go

FHP

Go

Co

Me

Sigmoid

8

Morphology Study• Compare statistical differences

– White, black, coloured (race)

– Male and female (gender)

• Left and right symmetry

– Paired t-test

• Correlation and relationship between variables

– Regression curves

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

9

Statistical Shape Modelling• Model variation within a given set of

similar objects

• Train model on morphological data

– Estimate individual’s healthy or missing geometry from sparse input

• Validate model

– Use partial input not in training set

– Compare RMS error between actual and estimated

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

10

Statistical Shape ModellingIntroduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

*Reproduced from Zachow et al. (2005)

Hypoplastic mandible Mean mandible

shape

Adaptation of shape model to healthy part of mandible

Template for implant design

11

Patient-specific Implant Design1. Take CT scan

2. Convert to 3D model

3. Apply SSM

4. Produce adapted 3D model

5. Design patient-specific implant

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

12

Conclusion• Design of patient-specific mandibular

implants

– Statistically accurate

– Quick

– Unique to SA population

– Proudly South African

Introduction

Case Study

Morphology Study

Statistical Shape Modelling

Patient-specific Implant Design

Conclusion

13