Complete overview about anchoarge in orthodontics.

1. ANCHORAGE IN
ORTHODONTICS
Presented By :
Dr. Anil Kumar Godara
1

2. CONTENTS
Introduction
Definitions
Classifications of Anchorage
Biological aspects of Anchorage
Mechanical aspects of Anchorage
Anchorage loss
Anchorage in Removable Appliances
2

3.  Anchorage in fixed appliance mechanotherapy
 Tweed’s Anchorage preparation
 Tweed- Merrifield’s Appliance
 Beggs mechanotherapy
 Refined Beggs mechanotherapy
 Level anchorage System
 Vari simplex discipline- Wick Alexander
 Bioprogressive therapy – Ricketts 3

4.  Burstone’s therapy
 Inverse anchorage technique – Jose carriere
 Implants
 Pre adjusted Edgewise
 Roth
 MBT
 Conclusions
 References 4

5. Introduction
Active components
Generate forces
In one direction
Equal and opposite force
Newton’s third law of motion
“ Every action has an equal and opposite reaction.”
Orthodontic tooth movement
Force
Active components
5

6. The force used to move the teeth is derived
from certain anatomic areas which act as an
“ ANCHORANCHOR ”.
The resistance that the anchor areas offers to
these unwanted tooth movements is known
as “ANCHORAGEANCHORAGE”.”.
6

7. DEFINITIONS :
 Webster “a secure hold sufficient to resist a heavy
pull.”
 Moyers :
“ Resistance to displacement.”
Active elements and reactive elements.
 T.M. Graber :
“The nature and degree of resistance to displacement
offered by an anatomic unit when used for the purpose
of effecting tooth movement.”
7

8.  Proffit :
“Resistance to unwanted tooth movement.”
“Resistance to reaction forces that is provided
(usually) by other teeth, or (sometimes) by the palate,
head or neck (via extraoral force), or implants in
bone.”
 Nanda :
“The amount of movement of posterior teeth (molars,
premolars) to close the extraction space in order to
achieve selected treatment goals.”
8

9. White & Gardiner: It is the site of delivery from
which a force is exerted.
Bennett and McLaughlin: Emphasized the need to
consider anchorage in all the three planes of space
i.e., horizontal, vertical and lateral (transverse).
9

10. Horizontal, Anchorage control means limiting the mesial
movement of the posterior segment while encouraging the distal
movement of anterior segment.
Vertical, Anchorage control involves the limitation of vertical
skeletal and dental development in the posterior segment and
limitation or vertical eruption of, or even intrusion of anterior
segments.
Transverse, It comprises of the maintenance of expansion
procedures, primarily in upper arch, and the avoidance of tipping or
extrusion of posterior teeth during expansion.
10

11. CLASSIFICATIONS:
 Moyers :
According to the manner of force
application:
1. Simple anchorage
2. Stationary anchorage
3. Reciprocal anchorage
11

12. 1. SIMPLE ANCHORAGE
 Dental anchorage in which the manner &
application of force tends to displace or change
the axial inclination of the tooth or teeth that
forms the anchorage unit in the plane of space in
which the force is being applied.
12

13. 2.STATIONARY ANCHORAGE
 Dental anchorage in which the manner &
application of force tend to displace the
anchorage unit bodily in the plane of space in
which the force is being applied.
13

14. 3.RECIPROCAL ANCHORAGE
 Anchorage in which the resistance of one or
more dental units is utilized to move one or more
opposing dental units.
14

15. According to the jaws involved:
1. Intra maxillary :
Resistance units are all situated within the same jaw.
2. Inter maxillary :
Anchorage units situated in one jaw are used to
effect tooth movement in other jaw.
15
Moyers

16.  Moyers :
According to the site of anchorage:
1. Intra oral :
Anchorage obtained from anatomical units
situated within the oral cavity.
16

17. 1. Teeth: it mainly depend up:-
a) Root form: its three basic types are
-Round: offer less resistance, as the resistance is offered only at a
single point with less surface area. E.g. bicuspids,palatal root of
maxillary molars.
-Flat: teeth wider buccolingually than mesiodistally offer more
resistance even than Round. E.g. incisors,buccal root of maxillary
molar.
-Triangular: offer maximum resistance due to greater surface
area.
b) Root length: larger & longer rooted teeth offer better anchorage
as they are deeply embedded in bone. E.g. maxillary canine.
17

18. c) Number of roots: multi rooted teeth have greater surface area than
single root.
d) Size of tooth: larger tooth act as better anchorage due to larger
surface area. E.g. molars compared to premolars.
f) Inclination of tooth: greater resistance offered when forces exerted
in opposite direction.
e) Number of teeth: multiple teeth act as better anchorage as group of
teeth resist more displacements.
g) Ankylosed tooth: serve as excellent anchor unit.
18

19. 2. Bone: Mandible bone has less amount of bone marrow,
more dense therefore better anchorage than maxillary
bone. E.g. hard palate, lingual surface of mandible. It also
get affected by any bone disease, periodontal disease, &
trabecular pattern.
3. Muscle: it mainly depends upon the hypo-tonicity &
hyper-tonicity of muscle. Hypertonic muscle can be
utilized as the anchorage. E.g. lip bumper.
4. Implants : commonly used are mini implants.
19

20. 2. Extra oral :
Anchorage obtained from anatomical units situated
outside the oral cavity.
1. Provides additional support for intraoral.
2. Prevents procumbancy of mandibular incisors.
3. Prevent buccal series of teeth from shifting forward.
4. Can move entire arch distally.
a) Cervical : eg. neck straps
b) Occipital : eg. Head gears
c) Cranial : eg. High pull headgears
d) Facial : eg. Face masks
20

21.  HEAD – GEAR
 Head gears are classified according to the point of origin of
force:
• Cervical – Anchorage obtained from nape of the neck
• Occipital / Straight pull – anchorage obtained from back of
the head. The line of traction is parallel to occlusal plane.
• Parietal / High pull – Anchorage obtained from upper part of
the head and always above the center of resistance of tooth.
• Combi pull – The line of traction is between high pull and
straight pull.
 Another variable in the headgear is the outer bow of the
facebow:
21

22.  FORCE AND DURATION OF WEAR :
• Most of the authors agree that the amount of force applied to
maxilla by the headgear should be between 400 – 800 gm. Light
continuous forces seem to produce more dental changes than
skeletal, Where as heavy force and intermittent wear is found to
produce more skeletal change.
• According to Marcotte force values of 200 gms per side in mixed
dentition and 500 gms per side in permanent dentition for 18-20 hrs
/ day suggested.
• Graber advocates force application of more than 400 gms for 10-12
hrs / day. 22

23.  FACE MASK:
• It is an extra oral anchorage
source.
• It derives anchorage from facial
bones.
• Sites of anchorage:
1. From skull
2. From chin
3. From skull & chin
• Force applied: approx. 1 pound
(450 gms) per side.
23

24. 3. Muscular :
Anchorage derived from action of
muscles.
eg. Vestibular shields.
24

25.  Moyers :
According to the number of anchorage
units :
1. Single or primary anchorage:
Anchorage involving only one tooth.
2. Compound anchorage:
Anchorage involving two or more teeth.
25

26. 3. Reinforced anchorage:
Addition of non dental anchorage sites.
eg. Mucosa, muscle, head, etc.
26

27.  Nanda :
Group A anchorage : critical / severe
-75 % or more of the extraction space is needed for
anterior retraction.
Group B anchorage : moderate
- Relatively symmetric space closure (50%).
Group C anchorage : mild / non critical
- 75% or more of space closure by mesial movement
of posterior teeth.
27

28. 28

29. Burstone
Group A: Posterior teeth contribute less than one
quarter to total extraction space closure.
29

30. Group B: Posterior teeth contribute from one quarter to one
half to total extraction space closure.
Group C: Posterior teeth contribute more than one half to
total extraction space closure.
30

31. BIOLOGICAL ASPECTS OF ANCHORAGE :
Anchorage value of tooth is its resistance to movement as
a function of its root surface area(pdl area).
Pressure in the PDL= Force applied to a tooth
Area of distribution in PDL
Anchorage control : Concentration of desired force and
dissipation of reactionary force.
31

32. Physiologic force
concept
F/A
 Tooth movement increases as pressure increases up to a
point, remains at same level over a broad range and then may
gradually decline with extremely heavy pressure.
32

33. Optimum orthodontic force
It is the lightest force and resulting pressure that
produces a near maximum tooth movement.
Pressure
Tooth
movement
Lighter force : physiologic and
maximum tooth movement.
Heavy pressure: might decline
tooth movement and traumatic ,
stressing anchorage.
Optimum force is equivalent to the capillary pulse pressure :20-26
gm/sq.cm of root surface area (Oppenhein & schwartz ).
33

34. For a tooth or group of teeth acting as anchorage
unit, pressure within the pdl should be kept as low
as possible.
Heavy forces
34

35. Differential effect of very large forces:
More movement of arch segment with the larger PDL
area.
Pressure Response Curve in 3 situations:for Anchor Teeth
(A) and Teeth to be Moved (M).
Pressure in the PDL of A-1 is less than the pressure in the
PDL of M-1.
35

36.  Factors affecting anchorage:
1st
factors:
Number of roots
multirooted > single rooted
Shape of the roots
triangular shaped root > conical or ovoid root
Length of the roots
longer rooted > shorter rooted
Size of the roots
larger surface area > smaller surface area
36

37. Anchorage value
Anchorage value of any tooth  roughly
eq. to its root surface area.
5 & 6 in each arch is appro. eq. in surface
area to 1,2 & 3.
Freeman’s
anchorage value
diagram
37

38. 2nd
factor – Pressure distribution
Single force vs force couple
•Tooth which is free to tip has a less anchorage value than a
tooth which is restricted in tipping by the application of a force
couple.
38

39. 3rd
factors – neighboring structures
Quality of the alveolar bone
Cortical anchorage:
Cortical bone vs. medullary bone
Muscular forces:
Horizontal growers vs. vertical growers
39

40.  Other factors affecting anchorage:
Traumatic extraction
2nd
molars inclusion
Relation of contiguous teeth
Forces of occlusion
Age of the patient
Individual tissue response
40

41. MECHANICAL ASPECTS OF ANCHORAGE :
Sliding mechanics
Force is required for 2 purposes
Bone remodeling
Frictional resistance
Controlling and minimizing friction is an important aspect
of anchorage control
41

42. Friction ???
Frictional force is related to force with which
surfaces are pressed together and is affected by -
-Nature of surface at the interface (rough or smooth,
chemically reactive or passive, modified by lubricants).
-Independent of the apparent area of contact.
42

43. Real contact occurs only at a limited number of
small spots: Asperities.
These asperities carry all the load between surfaces.
These are determined by applied load.
The co-efficient of friction is related to shear
strength of junction and yield strength of material.
43

44. Metal wire - ceramic
bracket
Plowing of asperites
Contributes to friction
But it is negligible in orthodontic application-
surfaces are ground relatively smooth
44

45. Thus total frictional resistance is sum of 3 components-
1) Force necessary to shear all junctions.
2) Resistance caused by interlocking of roughness.
3) Plowing component of total frictional force.
In practice if two materials are relatively smooth, not
greatly dissimilar in hardness, friction is largely determined
by Shearing components.
45

46. Surface quality of the wires
NiTi > ββTiTi > SS Roughness
There is little or no correlation between surface roughness and
coefficient of friction.
ββ Ti has greatest frictional resistance.Ti has greatest frictional resistance.
Significant influence on friction is-
It is because of surface defect, not due to quality of polishing..
46

47. This shows that as Ti content increases
Surface reactivity increases
Changes in surface chemistry has a major
influence of frictional behaviour.
47
Possible solution to this problem
Alteration of the surface of Ti wires-ion implantation
by nitrogen and carbon

48. Flexibility of arch wire and width of the bracket
A more flexible wire reduces the angle between wire and
brackets.
Self ligating brackets- reduced friction that allows more
effective sliding- better anchorage control. 48

49. Magnitude of friction
Retraction springs
Closing loops
- Springs and loops in wire-the wire will take the tooth
with them instead of teeth moving relative to wire.
49

50. Anchorage loss (AL) is a reciprocal reaction that could obstruct the
success of orthodontic treatment by complicating the
anteroposterior correction of the malocclusion.
Factors such as malocclusion, type and extent of tooth movement
(bodily/tipping), root angulation and length, missing teeth,
intraoral/extraoral mechanics, patient compliance, crowding,
overjet, extraction site, alveolar bone contour, interarch
interdigitation, skeletal pattern, third molars, and pathology (i.e.
ankylosis, periodontitis) affect anchorage loss.
ANCHORAGE LOSS
50

51. Anchorage loss may occur in all 3 planes of
space :
Sagittal plane:
- Mesial movement of molars,
- Proclination of anteriors.
51

52. Vertical plane:
- Extrusion of molars,
- Bite deepening due to anterior extrusion.
52

53. Transverse plane:
- Buccal flaring due to over expanded arch
form and unintentional lingual root torque,
- Lingual dumping of molars.
53

54. ANCHORAGE IN REMOVABLE
APPLIANCES:
Early removable appliances:
Completely tooth borne
Partly cast, partly wrought wire
Bimler appliance
54

55. Early removable appliances:
Crozat appliance
- Lingual extensions
- Heavy palatal bar
- High labial base wire
- Rest on molar clasp
55

56. Clasped Removable Appliances:
- Mostly intra oral anchorage is used.
- Active part, Wire components
- Retentive part, Clasps
- Acrylic Baseplate.
Baseplate :
- Point of attachment for the active components,
- Distribution of the reactionary forces to the teeth
and tissues.
56

57. To ensure adequate anchorage from baseplates:
- Extension as far as possible, also for stability,
- Close fit to the tissues,
- Contouring along the lingual gum margins,
- Adequate bulk of acrylic.
- Eg. Schwartz expansion plate.
57

58. Wire components:
- Labial bow:
Prevents proclination of incisors
58

59. Retentive components- Clasps are the retentive
components that assist in anchorage for the
removable appliances.
Intermaxillary anchorage:
- Elastics
Extraoral Anchorage - Headgears
59

60. SVED BITE PLATE
ANTERIOR INCLINED BITE PLANE
REMOVABLE FUNCTIONAL APPLIANCES:
Tooth borne appliances:
60

61. Anchorage obtained by:
- Capping of incisal margins of lower incisors.
- Proper fit of cusps of teeth into the acrylic.
- Deciduous molars used as anchor teeth.
Tooth borne appliances:
Activator, bionator, twin block
61

62. - Edentulous areas after loss of deciduous molars.
- Labial bow prevents anterior flaring and posterior
displacement of appliance.
62

63. REMOVABLE FUNCTIONAL
APPLIANCES:
Tissue borne appliances:
- Vestibular screen, Frankel’s function
regulator.
Anchorage by acrylic extending into
vestibule .
Headgears.
63

64. ANCHORAGE IN FIXED
APPLIANCES:
HISTORICAL PERSPECTIVE:
 ANGLE
• E arch :
- Tipping tooth movements.
- First to utilise stationary anchorage of 1st
permanent molars with clamp bands.
64

65. • Long clamp band: crown tipping resistance of
posterior teeth pitted against crown tipping
resistance of cuspid.
65

66. • Pin and tube appliance: root control by pins
soldered to labial archwire.
• Ribbon arch appliance: size of archwire itself did
not provide anchorage of posterior teeth.
66

67. “ When teeth are tipped distally as they are in
anchorage preparation, osteoid tissue appears to be
laid down adjacent to the mesial surface of the tooth
being moved distally.”
- Kaare Reitan
TWEED TECHNIQUE: 1944
67

68.  First Degree Anchorage preparation
Anchorage preparation:
First degree: ANB = 0 – 4
- mandibular molars must be uprighted and
maintained
- direction of pull of intermaxillary elastics should
be perpendicular to long axis of the tooth
68

69.  Second degree anchorage preparation
Second degree: ANB > 4.5
- mandibular molars must be distally tipped till distal
marginal ridges are at gum level
- direction of pull of Cl II elastics should be greater
than 90 to the long axis of the tooth
69

70.  Third degree or total anchorage preparationThird degree or total anchorage preparation
Third degree: ANB =5,
- total discrepancy = 14- 20 mm.
- mandibular molars must be distally tipped till distal
marginal ridges
are below gum level
- jigs are required
for anchorage
70

71. Mandibular anchorage prepared first by distal tipping
of the canines, premolars and first and second
molars.
Resist displacement
by Cl II elastic force
Stabilizing arch
wire: .0215 by .0275
71

72. Hooks soldered for intermaxillary elastics and/ or
headgear on the wires
High pull headgear: b/w centrals and laterals
Intermediate pull headgear and elastics: b/w laterals
and canines
72

73. Sequential mandibular anchorage preparation,
developed by Merrifield, in 1965, is the system that
allows mandibular anchorage to be prepared quickly
and easily by tipping only two teeth at a time to their
anchorage prepared position . This system uses high
pull headgear rather than class III elastics for support ,
unlike , the en masse anchorage of the Tweed era , it is
controlled, sequential, and precise. It is accomplished
by using ten teeth as “anchorage field 10- 2 system ”.
TWEED MERRIFIELD TECHNIQUE: 1965
73

74.  0.022 slot.
 Denture preparation:
Mandible:
• 20 degree tip back achieved.
• Straight pull J hook headgear used to
upright cuspids and apply distal force to
terminal molars.
74

75. Maxilla:
• 10 degree distal tip achieved.
• High pull J hook headgear used.
75

76. Class III elastics not used.
Tip backs used instead of second order bends: better
incisor control.
Maxillary third order bends applied sequentially
(anterior lingual root torque, posterior buccal root
torque).
76

77. • Sequential anchorage: the 10-2 system.
 MANDIBLE:
• 0.0215 by .028 continuous arch wire used.
• Ten teeth anterior to the second molars are stabilised
while the two terminal molars receive the active force.
• High pull headgear used.
• Second molars: +10 to +15
• First molars: 0 to –3 tip
• Second premolars: 0 to –5
77

78. • Distal tip of 10 degree in first molars with
compensation bends in 2nd
molars.
• High pull headgear.
• End of 1 month: second molars: +10 to +15
first molars: +5 to +8
second premolars: 0 to -3
78

79. • 10 degree tip in second premolar region with
compensating bend just mesial to first molar bracket.
• High pull headgear only at night.
• Second premolars: 0 to 5 degree tip.
79

80.  MAXILLA:
• Sequential force from first molar onwards.
• 10 degree tip placed.
80

81. • High pull headgear used for enhancing molar effect
and incisor intrusion.
• Next appointment: additional 5 degree tip placed on 1st
molar.
• Second molar : 20
• first molar : 15
• second premolar: 10
81

82. • 1950s by Dr. Begg in Australia
• Use of vertical slot.
• Use of light forces for tipping teeth.
• Use of optimal forces, so that extra oral
forces are not required.
• No anchorage preparation necessary.
BEGG TECHNIQUE
82

83.  Storey and Smith’s experiment on differential
forces: 1954
• Series of animal experiments.
• Bodily applied force will slow the rate of tooth
movement through a bone compared with a tipping
force.
• Optimal force concept by Storey:
• “ There is an optimum range of force which
produces maximum amount of tooth movement
through bone, and with forces above or below this
range there is reduced tooth movement.”
General Concepts-
83

84. • Experiment using cuspid retraction spring:
• Free crown tipping retraction of cuspid
and bodily movement anchorage
resistance by molar and bicuspid.
84

85. • Optimal force range for moving canines
distally: 150-200 gm.
• Movement of molar unit occurred with
force values of 300-500 gm.
• Therefore, use of light differential forces
in Begg technique.
85

86.  Use of Light differential forces.
• By varying the forces applied per unit of
root surface area to individual teeth, it is
possible to control the relative rates of their
movement.
86

87.  Use of extraoral anchorage
• The tipping of upper and lower anterior teeth
distally and lingually in both extraction and non
extraction cases during stages 1 and 2 and then
uprighting them in stage 3 is always done in the
Begg technique . This free tipping , followed by
uprigting , requires far less time and force than
moving the teeth in an upright position . This is one
of the main reasons that headgear is never
required when the light wire technique is used.
87

88.  Anchorage preparation unnecessary
• The total of the forces exerted by the arch wires ,
their root torqueing and root tipping auxiliaries , the
intramaxillary space closing elastics and the
intermaxillary elastics is so light that the anchorage
provided by nature – that is , the natural firmness
with which the roots of anchor teeth are held in the
bone – is sufficient anchorage for the performance
of all tooth movements required for treatment of all
classes of malocclusion.
88

89.  Preventing anchorage failure
• The chief means of preventing anchorage failure is
to employ thin round steel arch wires of 0.016 inch
diameter , rubber elastics and root moving
auxiliaries , all of which exert tooth moving forces
of such low values that the anchor molars are
moved far less by these forces than the teeth mesial
to them .
• Another means of preventing anchorage failure is
not to move any teeth bodily other than the anchor
molars during the first two stages.
• Another means of preserving anchorage is to place
anchorage bends in the upper and lower arch wires
mesial to the anchor molar buccal tubes .
89

90. Anchorage bend
•Formerly called the tip-back bend.
•Bend whose vertex faces occlusally.
•Placed in buccal segment at some point mesial to the
tube.
90

91.  CONTROL OF ANTERIOR ANCHORAGE
• In addition to the need for preserving molar
anchorage , it is sometimes necessary to
make the anterior teeth the anchor teeth in
order to move posterior teeth mesially and to
reduce the extent to which anterior teeth are
moved back.
91

92. • One method of bringing posterior teeth forward is to
place auxiliary arch wires with vertical spurs on the
six upper and lower anterior teeth .
• Another method of bringing posterior teeth forward
is to place root tipping springs on the four canines
in order to prevent their crowns from being tipped
distally. These root tipping springs and spur must
not be activated , but must simply be passive.
92

93. • The begg technique is divided into three
separate and distinct stages that must not be
allowed to overlap . It is chiefly with the
object of preventing anchorage failure,
thereby insuring efficient control of
anchorage , that the technique is divided
into three distinct stages of tooth
movement.
93

94.  Anchorage considerations in stage I:
1. Sagittal:
Upper molar anchorage:
- upper Class I elastics not used.
- use TPA , when using power arms and
palatal elastics ( also consolidating the first
and second molars).
94

95.  Lower molar anchorage:
- Stiff lower wire ( 0.018”)
- Light (yellow or road runner) elastics.
- Molar stop in case of Class II and lower
Class I elastics.
-Use lip bumper in critical anchorage
cases.
95

96.  Anchorage control in stage II:
• Use of heavy arch wires ( 0.018 or 0.020) to
maintain rotational correction, deep bite
correction and arch form.
• Also resist distobuccal rotational tendency
of molars due to Class I elastics.
• Mild anchor bends to maintain over bite
correction.
96

97.  Anterior Anchorage control in stage II:
• Anterior anchorage for posterior protraction:
- braking springs,
- angulated T pins.
- combination wires with
anterior rectangular ribbon
mode and posterior round wire.
- torquing auxiliaries like
two spur and four spur or MAA.
97

98.  Anchorage control in pre stage III:
• Upper wire: Gable bend for holding the deep bite
correction and uprighting distally tipped molars.
• Lower wire: gable and anchor bends.
• Inversion of segments to avoid canine extrusion
due to gable bends.
• End of arch wires are bent back to prevent
opening of extraction spaces.
98

99.  Control of anchorage in stage III:
• Minimise need for root movements by:
- careful diagnosis and planning of extractions.
- controlled tipping of incisors.
• Use of heavy base wires ( 0.020 ).
• Lighter auxiliaries and uprighting springs.
• Light Class II elastics.
99

100.  Control of anchorage in stage III:
• Reinforcement of anchorage:
1. Sagittal:
- reverse torquing auxiliary on lower incisors .
- headgear or TPA on upper molars and lip bumper
on lower molars.
2. Vertical:
- high pull headgear, TPA or posterior bite blocks.
- molar uprighting springs in case of second
premolar and first molar extraction cases .
100

101. 3. Transverse:
- contraction and toe-in in heavy base
wires.
- TPA or overlay wires.
- molar torquing auxiliary for buccal root
torque.
101

102. Anchor curve instead of anchor bend.
- Suggested by Mollenhauer.
-Causes extrusion of premolars – indicated in
low angle growing patients.
Anchorage reinforcement mechanisms-
-TPA
-Head gear
- Lip Bumpers
REFINED BEGG
102

103. • Differential force concept was misunderstood.
• Excessive retraction Prevented in refined begg
by applying efficient brakes along with heavy
differential forces.
103

104. •The method of bringing posterior teeth forward without
tipping the crowns of the six upper and lower anterior teeth
too far back is to place the now well-known auxiliary arch
wires with vertical spurs on the six upper and lower anterior
teeth.
• These auxiliary arch wires, when used for this purpose, must
not be activated sufficiently to torque the roots of the upper
and lower incisors lingually, but must be more or less passive
so that they will do no more than keep the upper and lower
incisors upright, thus acting as “breaks”, which produce
sufficient resistance-that is, anchorage-for moving the
posterior teeth forward during the second stage of treatment. 104

105. • Anchorage considerations in stage I
• Stiffer wires
• Light anchor bends
• Light or ultra light elastics
• Molar stops
• High pull headgear
• TPA
• Lip bumper in critical anchorage cases.
105

106.  Anchorage control in stage II:
• Use of heavy arch wires ( 0.018 or 0.020) to
maintain rotational correction, deep bite
correction and arch form.
• Maintain all the corrections of stage I.
• Also resist distobuccal rotational tendency of
molars due to Class I elastics.
• Mild anchor bends to maintain over bite
correction.
106

107. • Stage III – most complicated and anchorage
consuming.
 Control of anchorage in stage III:
• Minimise need for root movements by:
- careful diagnosis and planning of extractions.
- controlled tipping of incisors.
- use of brakes.
• Use of heavy base wires ( 0.020 ).
107

108. • Lighter auxiliaries(2 spur or 4 spur) and uprighting
springs.
• Light Class II elastics.
• Monitor anchorage in all 3 planes,
Palatal root torquing auxiliary
Distal root uprighting auxiliary
108

109.  Differences between conventional Begg and
refined Begg:
• Use of Special grade wire in conventional Begg as
opposed to P and P+ and Supreme.
• Use of lighter elastic forces in refined Begg.
• Use of extraoral anchorage and other reinforcements
in refined beggs.
• Use of lighter torquing auxiliaries and springs
( 0.009, 0.010, 0.012 as opposed to 0.014 and 0.016) .
109

110. • Dr. Lawrence Andrews , 1972.
• Preadjusted bracket system.
• Extra torque added to incisor brackets to prevent
bite deepening.
• Anti-tip and anti-rotation features in canine,
premolar and molar brackets: extraction and non-
extraction series.
• Same force levels and treatment mechanics as
previous systems.
STRAIGHT WIRE APPLIANCE: 1972
110

111. Bioprogressive therapy: 1978
 Dr. Rickets proposed the concept of Bioprogressive therapy to
enhance the anchorage.
 The concept of cortical bone anchorage implies that to anchor a
tooth , its roots are placed in proximity to the dense cortical
bone under a heavy force that will further squeeze out the
already limited blood supply and thus anchor the tooth by
restricting the physiological activity in an area of dense
laminated bone.
111

112. Three main aspects of tooth movement & cortical bone
support:
• Avoid cortical bone support where ever possible & direct the roots
through the less dense & more vascular trabecular bone. Light forces
are used.
• Anchor tooth by placing their roots adjacent to the denser cortical
bone .
• When treatment objectives require that we move teeth through the
supporting cortical bone, where the dense bone cannot be avoided but
must be remodeled,the forces must be kept even lighter to respect the
character of bone and its limited blood supply & physiological
response.
112

113.  Clinical applied aspects:
• Adverse effects of light continuous round wires
with reverse curve of Spee and tieback: lower
incisors thrown against the lingual cortical plate
causing more forward movement of lower molars.
• Class III elastics with high pull headgear: extrusive
effect on lower incisors and upper molars.
113

114. • Lower utility arch:
• Position of lower molar allows for cortical
anchorage:
- buccal root torque of lower molars.
- Tooth movement through dense cortical bone is
retarded because of reduced blood supply, which
diminishes resorption.
• Tip back: gain in arch length – 4mm.
• Headgears: cervical, combination and high pull.
114

115. Level anchorage system :1981
• Terrell L. Root -1981 - combination of straight wire
appliance and anchorage preparation as advocated
by Holdaway.
• Aim – quantify the anchorage requirement.
• 018 edgewise slot.
• Orderly manipulation of need and availability of
anchorage.
115

116.  The severity of the malocclusion is quantified as a function of
seven clinical variables:
1. Depth of curve of Spee.
2. Lower arch discrepancy: crowding or spacing.
3. Space needed to upright lower anteriors.
4. Anchorage needed to retract lower canines.
5. Anchorage needed to correct A-N-B.
6. Additional anchorage needed if mandibular plane angle is high,
additional anchorage available if mandibular plane angle is low.
7. Anchorage needed to retract upper anteriors in extraction cases.
116

117.  How much lower arch length is required to correct these
seven variables-
1. Depth of the curve of spee-It takes 1 mm of arch length to
level 1 mm of curve.
2. Lower arch discrepancy- it takes 1 mm of arch length to
correct each millimeter of crowding.
3. Space to upright the lower anteriors- Subtract the goal
position of the lower anteriors from their original position
and multiply by two (both sides).
117

118. 4. Lower buccal anchorage to retract the canines-The
canines; must be retracted a total of the anterior discrepancy
plus the space needed to upright the lower anteriors, Add
those two values and divide by 6 to determine how far the
lower buccal segments come forward during canine
retraction.
5. For retracting six anterior teeth in first premolar
extraction case 3mm of space is needed in lower arch.
In second premolar extraction case, retracting 8 teeth
needs 4mm space.
118

119. 6. Additional anchorage -. If Frankfort mandibular plane
angle is higher by 8 than average then the case will take 1mm
of additional anchorage. If the FMPA is lower by 80
than
average 1mm of anchorage is available.
119
 High pull headgear to maxillary 1st
molars or J hook headgear to
anteriors: reduction in ANB by 1 degree every 6 months.
 Palatal bar: decreases vertical descent due to tongue pressure.
 Delaying upper first premolar extraction by one year: reduces
mandibular anchorage space by 1mm.
 Class III elastics worn 24 hrs: flatten the curve of Spee and
upright buccal segments at the rate of 1mm / month.

120. Vari-simplex discipline-Alexander
• Treatment philosophy – Tweeds fundamentals.
1. Anchorage preparation.
2. Positioning Mandibular incisors over basal
bone.
3. Orthopedic alteration using head gear.
• Dr.Trammel 1980 advocated that by
incorporating -6 degree of distal tip in lower
first molars -2mm arch length is gained.
120

121.  Key objective
• Well proportioned face with consistent skeletal
pattern.
Non extraction therapy used as far as possible
By -Interproximal enamel reduction.
-Control of Mandibular incisor position with –ve torque.
121

122. Duration of wear of head gear
• Depends on skeletal pattern.
• If pretreatment ANB is 3 degree or less-night time
wear only.
• If ANB is 3-5 degree 10hour per day.
• If ANB is more than 5 degree 14 hour per day and
more.
122

123. Diagnostic principle
 Is to position mandibular teeth within arch with 4
goals in mind-
• 1) Incisor upright over basal bone.
• 2) Cuspids not expanded.
• 3) Level curve of spee.
• 4) Non extraction therapy as far as possible.
123

124. • Arch divided into 1 anterior and 2 posterior
segments, treated as separate units.
• Frictionless mechanics using TMA springs; low
load deflection rate.
• Differential space closure: anterior retraction or
posterior protraction or both should be possible.
• Proper moment to force ratios applied.
BURSTONE’S SEGMENTAL ARCH TECHNIQUE:
( 1982)
124

125. ANCHORAGE UNITS
Posterior units consists of–Premolar,1st molar,
2nd molar.
 Connected by TPA in the maxilla & Lingual
arch in the mandible.
 Stabilizing segments uses – 19x25, 21x25 SS /
TMA
125

126. GROUP –A ANCHORAGE
• Requires a relative increase in the posterior M/F ratio &
decrease in the anterior M/F ratio.
• T Loop is positioned closer to the posterior segment.
• Applying differential M/F.
•Ratio(12:1) for bodily translation.
126

127. GROUP -B ANCHORAGE
 Requires equal translation of the anterior & posterior
segments into the extraction space.
 Equal & opposite forces & moments are indicated.
 T- loop is placed in the center b/w anterior & posterior
attachments.
 M/F ratio needed = 10:1 for translation.
127

128. GROUP- C ANCHORAGE
• Alpha moment is increased relative to the Beta
moment.
• Spring is positioned closure to the anterior
segment.
• Anchorage reinforcement
• Intermaxillary elastics
• Protraction headgear
128

129.  Staggers and Germane (1991)
• Placement of gable bend near the beta
moment to increase the M/F ratio.
 Kuhlberg and Burstone (1997)
• Use of a loop with symmetric angulation
but asymmetric placement.
129

130.  Before 1986, only brackets with
vertical slots, such as ribbon arch
appliances, could be used to produce
differential tooth movement. Precise
mesiodistal angular control was
lacking, and the vertical slots hindered
archwire placement, allowing
excessive tipping during retraction and
making finishing difficult.
DIFFERENTIAL STRAIGHT ARCH
TECHNIQUE
[TIP EDGE BRACKETS]
ANCHORAGE IN FIXED APPLIANCES:
130

131. CHRISTOPHER in 1992 introduced the Tip-Edge
bracket Its unique slot now make it possible to utilize
differential mechanics with an edgewise appliance..
131

132. ANCHORAGE CONSIDERATIONS -
• Differential force technique-
• Extra oral anchorage is absolutely not needed in this
technique.
• Reduced friction - Very light forces can be used - Less
strain on the anchor teeth.
• Anteroposterior & vertical control – Anchor bend.
132

133.  With conventional edgewise appliances, distal crown tipping is
limited because of adverse archwire deflection. The edgewise
bracket create torque and cause bite deepening.
 With the Tip-Edge concept, these problems are addressed
modifying the bracket slot rather than the archwire mechanics.Tip
edge bracket eliminate couple and permit bite opening .
 VERTICAL CONTROL-
133

134.  VERTICAL CONTROL DURING SPACE CLOSURE-
CONVENTIONAL SLOT
TIP – EDGE SLOT
134

135. A
A-Retraction of canine with no flexing of wire in tip edge bracket-
B-Edgewise bracket provides flexing of wire during canine
retraction.
 The Tip-Edge slot eliminates archwire deflection during
retraction and allows differential tooth movement without
deepening the bite.
135

136.  Anchorage control in MBT -
• Definition – Tooth movement needed to achieve
passive engagement of steel 19 x 25 wire of suitable arch
form into a correctly placed .022 preadjusted bracket
system.
• Anchorage loss – maximum in the first stage.
MBT VERSATILE †
SYSTEM
136

137.  Major reason for anchorage loss ???
 Anchorage control
 The maneuvers used to restrict undesirable changes
during the opening phase of treatment, so that
leveling and aligning is achieved without key features
of the malocclusion becoming worse.
Mesial tip built into the bracket system
137

138.  1st
step in anchorage control
Recognize the anchorage needs of the case
Diagnosis and treatment planning stage
138

139.  Inbuilt tip: Proclination of
anteriors (especially uppers).
 Elastic forces : Anchorage
loss, distal rotation of
anteriors, bite deepening and
increase in curve of Spee.
Roller coaster effect
Anchorage control in the horizontal plane:
139

140.  Roller coaster effect has been eliminated from the
present day practice-
• Reduced tip in bracket system.
• Light arch wire forces.
• Use of lacebacks instead of elastic forces.
140

141. • Lacebacks from most distally banded molars to
canines to Restrict canine crown from tipping
forward.
• Bending the archwire back immediately distal to the
molar tube.
 Control of anterior segment:-
141

142.  Bendbacks for A/P incisor control -
• Bend is placed 1-2 mm distal to molar tube.
142

143.  Restrict canine crown from tipping forward.
 Distalizing canines without causing unwanted
tipping .
Lace backs
143

144.  Continued till rectangular SS wire stage.
 Discontinued if space appears between lateral &
canine.
144

145.  Robinson in 1989:
 57 Premolars extraction cases.
- Lower molars moved forward 1.76
mm on an average with lacebacks
and 1.53mm without lacebacks .
- Lower incisors moved distally 1.0
mm with lacebacks and 1.47 mm
without lacebacks.
145

146.  Greater need in upper arch:-
 The upper molars move mesially more easily than lower
molars.
 Upper anterior segment has larger teeth than lower anteriors.
 Upper anterior brackets have more tip built.
 Upper incisors require more torque control & bodily
movement.
 More Class II type malocclusions than Class III.
 Control of the posterior segments- Upper arch-
146

147.  A/P anchorage support & control for upper molars –
Head gears TPA
 Headgears : cervical, combination and high pull with long outer
bow.
 Palatal bar.
147

148. • Use Soldered lingual arch.
• Severe anterior crowding cases: push coil springs
with class III elastics; reinforced with upper palatal
bar and high pull headgear.
 Control of posterior segments: Lower arch-
148

149.  Incisor vertical control:
 Temporary increases in overbite during anterior
retraction.
 Avoid bracketing incisors or avoid tying the
wire in the incisor brackets.
Anchorage assessment in the vertical plane:
149

150.  Avoid early engagement of highly placed canines .
150

151.  Molar vertical control: prevent extrusion of posterior
teeth and opening up of mandibular plane angle ( high
angle cases).
 Upper second molars not banded or archwire step
placed distal to first molars.
 Avoid extrusion of palatal cusps during expansion :
fixed expander with headgear.
151

152. • Palatal bars lie away from palate by 2mm: vertical
intrusive effect of the tongue.
• Avoid cervical pull headgear.
• Upper or lower posterior biteplates.
152

153. • Intercanine width
maintained: avoid
uncontrolled
expansion.
• Molar crossbites:
bodily correction to
avoid overhanging
palatal cusps.
Anchorage assessment in the lateral plane:
153

154. • The conventional methods of reinforcing anchorage are less
than ideal, because they either rely on structures that are
themselves potentially mobile [teeth] or they rely too heavily
on patient compliance [ HG & Elastics].
• Skeletal anchorage overcomes many of these shortcomings.
• Boucher: Implants are alloplastic devices which are
surgically inserted into or onto jaw bone.
SKELETAL ANCHORAGE
154

155. Direct anchorage
Utilizes force from the actual implant that takes the
place of a missing tooth & eventually supports a dental
restoration .
Indirect anchorage
Placed solely for orthodontic purposes & is
generally removed once its anchorage duties have been
fulfilled.
TYPES OF SKELETAL ANCHORAGE
155

156. In 1970 and 1980 concept of implants was
introduced in orthodontics, which provides absolute
anchorage. The best anchorage from a biological
point of view is from the periodontal ligament, where
no change in the turnover occurred.
Ideal intraoral implants for orthodontic anchorage
should resist push-pull, intrusive, and extrusive
forces.
156

157.  The majority of dental implants have been fabricated
of inert materials for example, metals, polymers,
ceramics, and vitreous carbons. The body's response to
these ''inert implants'' has been to surround them with a
fibrous capsule. The desired immobility of these
implants has relied on the relative thinness of the
fibrous capsule and growth of bone and fibrous tissue
into the holes, grooves, or micro porosities to establish
mechanical locking between the implant and the
surrounding bone.
157

158.  Anchorage source:
• Orthopedic anchorage:
- Maxillary expansion.
- Headgear like effects.
• Dental anchorage:
- Space closure.
- Intrusion ( anterior and posterior).
- Distalization.
158

159.  Implants for orthopedic anchorage:
 Maxillary protraction:
- Smalley (1988)
- Insertion of titanium
implants into maxilla,
zygoma, orbital and occipital
bones of monkeys.
-12-16mm widening of sutures
with 5-7mm increase in overjet.
159

160.  Parr, Roberts, et al (1997):
• Studied Midnasal expansion using endosseous
titanium screws; through a Rabbit study.
• Stability of implants seen for 1N and 3N loading.
160

161.  Implants for intrusion of teeth:
• Creekmore ( 1983)
- Vitallium implant for
anchorage while intruding
upper anterior teeth
6mm intrusion with
25degrees torque.
161

162.  Southard (1995)
• Comparison of intrusion
potential of titanium
implants and that of teeth
Titanium implants placed
in extracted 4 premolar
area of dogs.
• Intrusive force = 60gms
162

163.  Implants for space closure:
• Eugene Roberts: use of
retromolar implants for
anchorage.
• Size of implant: 3.8mm width
and 6.9mm length.
• 0.019 x 0.025 TMA wire from
premolar to retromolar implant
to prevent distal movement of
premolar.
163

164. CLASSIFICATION
 Based on implant morphology-
1) Implant disks
- Onplant
2) Screw designs
- Mini-implant
- Orthosystem implant system
- Aarhus implant
- Micro implant
- Newer systems – Spider screw,OMAS system
164

165. 3) Plate designs
- Skeletal anchorage system [SAS]
- Graz implant supported system
- Zygoma anchorage system
 BASED ON AREA OF PLACEMENT
- Subperiosteal implants
- Osseous implants
- Inter dental implants 165

166. ONPLANT
 Block and Hoffman (1995)
“an absolute anchorage device”
 Titanium disc- coated with hydroxyapatite on
one side and threaded hole on the other.
 Inserted subperiosteally.
166

167. Placed in Zygoma, body & ramus area, midpalatal
areas.
 Skeletal anchorage systems.
 Graz implant supported system.
 Zygoma anchorage system.
OSSEOUS IMPLANTS
167

168. Umemori,Sugawara, AJO-1999.
Titanium miniplates, stabilized with screws.
Different designs - L, Y, T.
 Placement in key ridge for upper molar and ramus for lower
molar intrusion.
Uses:
-Molar intrusion .
-Molar intrusion and distalisation.
-Incisor intrusion.
-Molar protraction.
-Molar extrusion.
SKELETAL ANCHORAGE
SYSTEM
168

169.  Karcher & Byloff,2000.
 Modified titanium miniplate.
 4 miniscrews, 2 oval shaped cylinders.
 Support for Pendulum appliance.
GRAZ IMPLANT SUPPORTED
SYSTEM
169

170. ZYGOMA ANCHORAGE SYSTEM
 Hugo De Clerck & Geerinckx,
JCO-2002.
 Curved Ti miniplate.
 3 screws of 2.3 mm.
 Zygomaticomaxillary buttress area for
enmass retraction of anterior teeth.
170

171. Developed by Wehrbein, 1996.
Titanium screw implant – 3.3mm.
Mid palate/ Retromolar area.
Available in two sizes- 4/6mm.
ORTHO SYSTEM IMPLANT
171

172. CONVENTIONAL DENTAL IMPLANTS
 Can only be placed in retromolar or edentulous areas.
 Too large for horizontal orthodontic traction.
 Troublesome for patients because of -
- Severity of the surgery.
- Discomfort of initial healing.
- Difficulty of oral hygiene maintenance.
 Time required for osseous integration.
172

173.  Endosseous implants.
 Smaller diameter.
 Mechanical retention.
 Advantages:-
- Placement is easy, can be done under LA.
- Brings about all types of tooth movement.
- Removal is easy.
INTER DENTAL IMPLANTS
173

174.  Mini-implant:
• Ryuzo Kanomi ( 1997).
• Small titanium screws 1.2mm diameter and
6mm length.
• Initially used for incisor intrusion.
• 6mm intrusion of mandibular incisors.
174

175. 1.Closure of extraction space.
2.Molar Protraction.
3.Molar distalization.
4.Intrusion.
5.Canine retraction.
6.Molar uprighting.
7.Midline correction.
8.Molar intrusion.
9.Extrusion of impacted canines.
10.Correction of canted occlusal Planes.
Mini implant
as an anchorage in orthodontics
175

176. MICRO-IMPLANTS
Park et al, JCO-2001
Placed in the buccal
sulcus/ palatal inter dental
areas.
176

177. Giuliano Maino , JCO 2003
 Self tapping mini screws available in
3 lengths– 7,9,11 mm
 3 Types
- Regular
- Low profile
- Low profile flat
SPIDER SCREWS
177

178.  Impacted titanium posts:
- Bousquet and Mauran (1996).
- Post impacted between upper
right first molar and second
premolar extraction space on
labial surface of alveolar process
Perpendicular to bone surface.
178

179. 179

180. REQUIREMENTS OF AN ORTHODONTIC
ANCHOR IMPLANT
Small.
Affordable.
Easy to place.
Resistant to orthodontic forces .
Able to be immediately loaded.
Usable with familiar orthodontic mechanics.
Easy to remove.
180

181. Alveolar bone in an extraction site.
Palate in the median / paramedian area.
Retroincisive.
Retromolar site.
Anterior nasal spine.
Chin symphysis.
ANATOMICAL SITES
181

182. - 6MM PALATAL IMPLANT SUPPORTED MOLAR
DISTALIZATION WITH TPA FOR ANCHORAGE.
- DISTALIZATION IS CARRIED OUT WITH OPEN COIL
SPRING BETWEEN PREMOLAR AND MOLAR.
Departmental Cases
182

183.  6MM IMPLANT PLACED BETWEEN THE TWO CENTRAL
INCISORS AND FORCE APPLIED WITH E-CHAIN FROM
IMPLANT TO THE MODIFIED RECTANGULAR DESIGN MADE
WITH 19X25 SS WIRE FOR PROTRACTION WITH INTRUSION .
183

184.  Closure of extraction spaces by implant as an
anchorage ( 6 mm ) placed between premolar and molar
and niti closed coil spring between the L Hook and
implant.
Lingual mechanics
184

185.  Loss of posterior anchorage during extraction
space closure can exacerbate the curve of spee
and deepen the bite.
 Microscrew provide reliable skeletal anchorage
for anterior retraction in either arch, whether a
single tooth at a time or en masse.
185

186. CLINICAL CONTROL ANCHORAGE
Few teeth are moved at a time.
As many teeth as possible are included in
anchorage unit.
Appliance produce light forces.
186

187.  Things that tend to slip posterior anchorage
forward:
• Use of resilient wires and continuous wires to level a
deep curve of Spee.
• Rapid bracket alignment with very resilient wires.
• Attempts to upright distally inclined canines.
• Attempts at moving maxillary incisor roots lingually.
• Attempts at expansion with a labial arch wire.
• Using a reciprocal force system to retract extremely
proclined anteriors.
187

188.  Ways to avoid anchor loss:
• Leveling with small flexible wire.
• Retraction of lower anteriors using a facebow.
• Band second molars in the beginning of treatment.
• Use of utility arch to level curve of Spee.
• Use of multiple short Cl II or Cl III elastics for
intra-arch adjustment: do not extrude molars and
do not change cant of occlusal plane.
188

189. CONCLUSION
• Conservation of anchorage in the correct areas and at the proper
time is one of the most important & difficult tasks in orthodontics.
•In many cases , the successful outcome of the treatment depends
on treatment planning.
• The biomechanical setup that delivers the correct type &
magnitude of force must be established to achieve the goals of the
treatment.
•Anchorage should be planned and taken care of from the first day
of treatment.
189

190. References:
1. Thomas M Graber, Brainerd F Swain: Orthodontic current
principle and technique, University of Chicago.
2. Robert E Moyers: Handbook of Orthodontics, Fourth edition,
University of Michigan.
3. T.M.Graber. Orthodontics principles and practice, Third edition.
4. William R.Proffit with Henery W field: Contempory
orthodontics, second edition, Mosbyin 1993.
5. Ravindra Nanda: Biomechanics in Clinical orthodontics.
190

191. 6. Johnston. Anchorage loss: A comparative analysis Charles H.Tweed Int
Found 1988:16:23-27.
7. Christopher K Kesling:”The Tip edge concept: Eliminating unnecessary
anchorage strain; Am.J. Orthod: 16-178,1992.
8. Richard P McLaughlin: Anchorage control during leveling and aligning
with a preadjusted appliance, Am.J.Orthod, 687-696,1991.
9. Roth, R.H: The straight wire appliance 17 year later, J.Clinic.Orthod.21:
632-642,1987.
10. Roberts W.F. Nelson: “Rigid implant anchorage to close a mandibular
extraction site”, J. Clin. Orthod. 28 : 693-704, 1994.
191

192. 11. Linkow L: “Implanto-Orhtodontics”; J. Clin. Orthod. 4 : 685-
705,1970.
12. Creek more and Eland, “ The possibility of skeletal anchorage”, J.
Clin. Orhtod. 17: 266-271, 1983.
13. Yung, Lee: “ Micro-implants for orthodontic anchorage”, J. Clin.
Orthod.31: 201-204, 2001.
14. Hugo Clerk, Geernickx: The Zygoma Anchorage System”, J. Clin.
Orthod. 36(7), 455-458, 2002.
15. Robert H.W.Strang :Orthodontic anchorage; Angle Orthod, 173-
186,July 1941. 192

193. Thank You
193