The accuracy of visualized treatment objectives in Bimaxillary Protrusion patients.

132 Pages·2009·0.8 MB·English

by  Murphy, Desmond.

THE ACCURACY OF VISUALIZED

TREATMENT OBJECTIVES IN

BIMAXILLARY PROTRUSION

PATIENTS

Desmond Murphy
Department of Orthodontics
Faculty of Dentistry
University of Western Cape, Cape Town
March 2008
THE ACCURACY OF VIS  UALIZED TREATMENT
OBJECTIVES IN BIMAX ILLARY PROTRUSION

PATIENTS

MChD thesis of Dr Desmond Murphy, submitted in partial fulfillment of the
requirements for the degree of MChD, Department of Orthodontics, Faculty of
Dentistry, University of the Western Cape. March 2008.
Supervisor: Professor AMP Harris, Faculty of Dentistry, University of the
Western Cape.
TABLE OF C  ONTENTS
List of Tables i

List of Figures iii

Appendix iv

Declaration v
Acknowledgments vi
Dedication vii
Abstract viii
CHAPTER 1 INTRODUCTION 1

CHAPTER 2 LITERATURE REVIEW 4
2.1 Aetiology 4

2.2 Features of bimaxillary protrusion 8

2.3 Treatment of bimaxillary protrusion 11

2.4 Growth prediction 14
2.4.1 Craniofacial Growth Data 15
2.4.1.1 Broadbent Bolton Growth Study 16
2.4.1.2 Burlington Growth Study 18
2.4.1.3 Denver Growth Study 18
2.4.1.4 Fels Research Institute Growth Study 19
2.4.1.5 Forsyth Growth Study 20
2.4.1.6 Iowa Growth Study 20
2.4.1.7 Krogman Philadelphia Growth Study 21
2.4.1.8 Matthews Implant Collection 22
2.4.1.9 Meharry Growth Study 22
2.4.2.0 Michigan Growth Study 23
2.4.2.1 Montreal Growth Study 23
2.4.2.2 Oregon Health Study 24
2.4.2.1 Visualized Treatment Objectives 25
a) Ricketts VTO  29
b) Holdaway VTO 30

c) Steyn VTO 31
d) Jacobson and Sadowsky VTO 31

2.4.2.2 Differences between VTOs 31
2.4.2.3 Advantages of VTOs 32
2.4.2.4 Limitations of VTOs 33
2.4.2.5 Reliability of VTOs 33

2.4.3 Hard and soft tissue response 36
2.4.4 Profile changes 38
2.4.5 Lip posture and lip length 39
2.4.6 Soft tissue chin 41
2.4.7 The nose 42
2.4.8 Treatment and soft tissue response 43
2.4.9 Incisor position 45
2.50 Incisor position and upper lip response 46

CHAPTER 3 METHOD AND MATERIALS 54
3.1 Aims and Objectives 54
3.2 Research sample 55
3.3 Cephalometric landmarks 56
3.4 Data measurement 62
3.5 Statistical analysis of the data 64
3.6 Intra-examiner variability 64
3.7 Ethics statement 64

CHAPTER 4 RESULTS 66
4.1 Soft tissue changes 66
4.2 Dental changes 82

CHAPTER 5 DISCUSSION 90

CHAPTER 6 CONCLUSION AND RECOMMENDATIONS 94

APPENDIX 96

REFERENCES 112
LIST OF  TABLES

  Page

Table 1 : Craniofacial growth studies 17

Table 2 : Upper lip response to incisor retraction 51

Table 3 : Digitized points used in the study 57

Table 4 : Example of a Data capture form (UWC3) 65

Table 5 : Facial angle prediction (Steyn) 67

Table 6 : Facial angle prediction (Jacobson & Sadowsky) 68

Table 7 : Facial angle prediction (Ricketts) 69

Table 8 : Facial angle prediction (Holdoway) 70

Table 9 : Comparison of the four VTO’s (Facial angle) 71

Table 10 : VTO predictions for superior sulcus depths 72

Table 11 : VTO predictions for subnasale 73

Table 12 : VTO predictions for skeletal profile convexity 74

Table 13 : VTO predictions for upper lip thickness 75

Table 14 : VTO predictions for upper lip strain 76

Table 15 : VTO predictions for the H-angle 77

Table 16 : VTO predictions for the lower lip to the H-line 78

Table 17 : VTO predictions for the inferior sulcus depth 79

Table 18 : VTO predictions for chin thickness 80

Table 19 : VTO predictions for lower lip to E-line 81

Table 20 : VTO predictions for the inter-incisal angle 82

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Table 21 : VTO predictions for  the upper incisor to palatal plane 83

Table 22 : VTO predictions for  the lower incisor to
mandibular plane 84

Table 23 : VTO predictions for the upper incisor to NA line (º) 85

Table 24 : VTO predictions for the upper incisor to NA line (mm) 86

Table 25 : VTO predictions for the lower incisor to NB line (º) 87

Table 26 : VTO predictions for the lower incisor to NB line (mm) 88

Table 27 : Accuracy of the four VTO’s 89

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LIST OF F  IGURES

  Page

Figure 1 : Pretreatment photographs of patient with bimaxillary

protrusion 12

Figure 2 : Posttreatment photographs of patient with bimaxillary
protrusion 13

Figure 3 : Cephalometric points digitized 56

Figure 4 : Soft tissue facial angle 60

Figure 5 : Superior sulcus depth 60

Figure 6 : Soft tissue subnasale to H-line 60

Figure 7 : Skeletal profile convexity 60

Figure 8 : Basic upper lip thickness 60

Figure 9 : H-angle 60

Figure 10 : Lower lip to H-line 61

Figure 11 : Ricketts E-line 61

Figure 12 : Digitizing apparatus 63

Figure 13 : Ricketts VTO 99

Figure 14 : Holdaway VTO 104

Figure 15 : Jacobson and Sadowsky VTO 111
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APPE NDIX

  Page

A. Data capture form 96

B. Ricketts VTO 97

C. Holdaway VTO 100

D. Steyn VTO 105

E. Jacobson and Sadowsky VTO 107

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DECLAR  ATION

I ………………………………………………………. declare that this thesis
entitled “The accuracy of Visualized Treatment Objectives in bimaxillary

protrusion patients in the Western Cape Population” is my own original work
and has not been submitted for a higher degree to any other institution. The
sources I have quoted have been acknowledged by means of references.

Signature : …………………………..

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ACKNOWLEDGEMENTS

1. To Professor Angela Harris for all her assistance, not only with this
thesis, but during the entire course. I will never be able to say thank you

enough for consenting to be my supervisor. I will remain eternally
grateful for her input, encouragement and guidance.

2. To Dr Ralph Ginsberg, a special thanks for allowing me to use his
records as part of this study.

3. To Dr Vince Joseph for making his surgery available to me and helping
with the digitizing.

4. To Professor Theuns Kotze for his advice and assistance with the
statistical analysis of the data and making this part of the study a very
pleasant experience.

5. To my consultants, Drs Ginsberg, Samsodien, Ferguson, Bellardie, Els,
Theunissen and Johannes.

6. To Professor Shaikh for all her advice and assistance during the 4 years
of study.

7. To Drs Oosthuizen and Amra for their assistance and encouragement.

8. To my fellow Registrars, Drs Nkosi and Suliman for making the 4 years
an enjoyable experience and a memorable one.

9. Lastly, but most importantly, to my family who sacrificed so much so that
I might realize my goal. The sacrifice indeed has been worth it.

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