Anchorage in orthodontics /certified fixed orthodontic courses by Indian dental academy

ANCHORAGE IN
ORTHODONTICS
INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com


NEWTON’S third law of motion :
“ Every action has an equal and opposite
reaction.”


DEFINITIONS :
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.”

DEFINITIONS :
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.”


DEFINITIONS :
Nanda :
“The amount of movement of posterior
teeth (molars, premolars) to close the
extraction space in order to achieve
selected treatment goals.”


CLASSIFICATIONS:
Moyers :
According to the manner of force
application:
1. Simple anchorage :
Resistance to tipping.
2. Stationary anchorage :
Resistance to bodily movement.

CLASSIFICATIONS:

3.

Reciprocal anchorage :
Two or more teeth moving in opposite
directions and pitted against each other
by the appliance.


CLASSIFICATIONS:
Moyers :
According to the jaws involved:
1. Intra maxillary :
Anchorage established in the same jaw.


CLASSIFICATIONS:

2. Inter maxillary :
Anchorage distributed
to both jaws.
Baker’s anchorage (1904)


CLASSIFICATIONS:
Moyers :
According to the site of anchorage:
1. Intra oral :
Anchorage established within the
mouth.


CLASSIFICATIONS:
2. Extra oral :
Anchorage obtained outside the oral cavity.
a.) Cervical : eg. neck straps
b.) Occipital : eg. Head gears
c.) Cranial : eg. High pull headgears
d.) Facial : eg. Face masks

CLASSIFICATIONS:


CLASSIFICATIONS:

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


CLASSIFICATIONS:
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.

CLASSIFICATIONS:
3.

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


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

CLASSIFICATIONS:
Burstone :
Group A arches
Group B arches
Group C arches


BIOLOGICAL ASPECTS OF
ANCHORAGE :
Factors affecting anchorage:
Number of roots
Shape, size and length of each root
multirooted > single rooted
longer rooted > shorter rooted
triangular shaped root > conical or ovoid root
larger surface area > smaller surface area

ANCHORAGE :
Cortical anchorage:
Cortical bone vs. medullary bone
Muscular forces:
Horizontal growers vs. vertical growers


ANCHORAGE :
Relation of contiguous teeth
Forces of occlusion
Age of the patient
Individual tissue response


ANCHORAGE :
Pressure in the PDL= Force applied to a tooth
Area of distribution in PDL
Tooth movement increases as pressure increases
upto a point, remains at same level over a broad
range and then may gradually decline with
extremely heavy pressure.
Anchorage control : Concentration of desired
force and dissipation of reactionary force

ANCHORAGE :
PRESSURE RESPONSE CURVE :


ANCHORAGE :
Anchorage situations :
Reciprocal tooth movement :
Equal force distribution over the PDL
eg. Midline diastema,
First premolar extraction site
Anchorage value depends on the root
surface area

ANCHORAGE :
Reinforced anchorage:
Distribution of force over a larger surface
area
Light forces vs. heavy forces
eg. Addition of extra teeth,
Extra oral anchorage

ANCHORAGE :
Stationary anchorage:
Bodily movement of anchor teeth vs.
tipping of teeth to be moved


ANCHORAGE :
Differential effect of very large forces:
More movement of arch segment with the
larger PDL area.
Questionable response.


MECHANICAL ASPECTS OF
ANCHORAGE :
Tooth movement is brought about after
overcoming the frictional resistance during
sliding of wire in the bracket.
Frictional force is proportional to the force
with which the contacting surfaces are
pressed together
Affected by the nature of the surface
Independent of the area of contact

ANCHORAGE :
Asperities :
Peaks of surface irregularities.


ANCHORAGE :
Local pressure at asperities causes plastic
deformation
At low sliding speeds, ‘stick slip’
phenomenon occurs
Anchor teeth feel reaction to both friction
and tooth moving forces


ANCHORAGE LOSS:
Anchor loss in all 3 planes of space :
Sagittal plane:
- Mesial movement of molars,
- Proclination of anteriors


ANCHORAGE LOSS:
Vertical plane:
- Extrusion of molars,
- Bite deepening due to anterior extrusion


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


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


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


ANCHORAGE IN
CLASPED REMOVABLE APPLIANCES:
- Active part,
- Clasps,
- Baseplate.
Baseplate :
- Point of attachment for the active components,
- Distribution of the reactionary forces to the teeth
and tissues.

ANCHORAGE IN
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

ANCHORAGE IN
Wire components:
- Labial bow:
Prevents proclination of incisors
Stationary anchorage.
Intermaxillary anchorage:
- Elastics
Headgears

ANCHORAGE IN
REMOVABLE FUNCTIONAL
APPLIANCES:
Reactionary forces:
- Sagittal
- Vertical
- Transverse


ANCHORAGE IN
APPLIANCES:
Tooth borne appliances:
- Sved bite plane:
stationary anchorage


ANCHORAGE IN
APPLIANCES:
Tooth borne appliances:
Activator, bionator,
twin block


ANCHORAGE IN
REMOVABLE FUNCTIONAL APPLIANCES:
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


ANCHORAGE IN
REMOVABLE FUNCTIONAL APPLIANCES:
- edentulous areas after loss of deciduous molars
- noses in upper
and lower interdental spaces
- labial bow prevents
anterior flaring and posterior
displacement of appliance


ANCHORAGE IN
APPLIANCES:
Tissue borne appliances:
- Vestibular screen, Frankel’s function
regulator
Anchorage by acrylic extending into
vestibule
Headgears

ANCHORAGE IN
APPLIANCES:
Tissue borne appliances:
- Vestibular screen


ANCHORAGE IN FIXED
APPIANCES:
Historical perspective
Edgewise: Angle, Tweed, Andrews, Ricketts,
Alexander, Roth, Burstone, Bennett and
Mclaughlin
Methods to reinforce anchorage
Begg: conventional and refined
Tipedge
Studies in anchorage
Newer methods inanchorage conservation

ANCHORAGE IN FIXED
APPIANCES:
HISTORICAL PERSPECTIVE:
ANGLE;
E arch :
- tipping tooth movements
- first to utilise stationary
anchorage of 1st permanent
molars with clamp bands

ANCHORAGE IN FIXED
APPIANCES:
Long clamp band: crown tipping resistance
of posterior teeth pitted against crown
tipping resistance of cuspid.
- simple anchorage vs. simple anchorage


ANCHORAGE IN FIXED
APPIANCES:
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


ANCHORAGE IN FIXED
APPIANCES:
Edgewise appliance:
0.022” slot
Utilised by Tweed


ANCHORAGE IN FIXED
APPIANCES:
TWEED TECHNIQUE:
“ 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

ANCHORAGE IN FIXED
APPIANCES:
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


ANCHORAGE IN FIXED
APPIANCES:
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


ANCHORAGE IN FIXED
APPIANCES:
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

ANCHORAGE IN FIXED
APPIANCES:
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

ANCHORAGE IN FIXED
APPIANCES:
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


ANCHORAGE IN FIXED
APPIANCES:
TWEED MERRIFIELD TECHNIQUE:
Sequential directional force edgewise
technique – 1965
.022 slot
20 degree tip back achieved
J hook headgear used to upright cuspids and
apply distal force to terminal molars

ANCHORAGE IN FIXED
APPIANCES:
Denture preparation:
Mandible:
20 degree tip back achieved
Straight pull J hook headgear used to
upright cuspids and apply distal force to
terminal molars


ANCHORAGE IN FIXED
APPIANCES:
Maxilla:
10 degree distal tip achieved
High pull J hook headgear used


ANCHORAGE IN FIXED
APPIANCES:
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)


ANCHORAGE IN FIXED
APPIANCES:
Sequential anchorage: the 10-2 system
MANDIBLE:
.0215 by .028 continuous archwire 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

ANCHORAGE IN FIXED
APPIANCES:
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


ANCHORAGE IN FIXED
APPIANCES:
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


ANCHORAGE IN FIXED
APPIANCES:
MAXILLA:
Sequential force from first molar onwards
10 degree tip placed


ANCHORAGE IN FIXED
APPIANCES:
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

ANCHORAGE IN FIXED
APPIANCES:
RICKETTS’ BIOPROGRESSIVE
TECHNIQUE: 1978
Quad helix:
holding appliance


ANCHORAGE IN FIXED
APPIANCES:
RICKETTS’ BIOPROGRESSIVE TECHNIQUE:
Adverse effects of light continuous round wires
with reverse curve of Spee and tieback: lower
incisors thrown against the lingual cortical plate
causing forward movement of lower molars
Class III elastics with high pull headgear:
extrusive effect on lower incisors and upper
molars


ANCHORAGE IN FIXED
APPIANCES:
Lower utility arch: late 1950s
Position of lower molar to allow for cortical
anchorage:
- tooth movement through dense cortical bone is
retarded because of reduced blood supply, which
diminishes resorption
- buccal root torque of lower molars
Tip back: gain in arch length – 4mm
Headgears: cervical, combination and high pull

ANCHORAGE IN FIXED
APPIANCES:


ANCHORAGE IN FIXED
APPIANCES:
THE STRAIGHT WIRE APPLIANCE:
Dr. Lawrence Andrews , mid 70s
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 nonextraction series
Same force levels and treatment mechanics as
previous systems

ANCHORAGE IN FIXED
APPIANCES:
LEVEL ANCHORAGE SYSTEM:
Terrell Root
Preadjusted appliance used with .018 slot
Anchorage:
- inherent resistance of teeth to move
- distance they can be allowed to move
Orderly manipulation of need and availability of
anchorage
High pull headgear to maxillary 1st molars or J
hook headgear to anteriors: reduction in ANB by

ANCHORAGE IN FIXED
APPIANCES:
Anchorage savers:
Palatal bar: decreases vertical descent due to
tongue pressure; reduction in space by 1mm
Delaying upper first molar 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


ANCHORAGE IN FIXED
APPIANCES:
Anchorage conservation during treatment in
level anchorage system:
Stabilization of upper arch: .018* .025 s.s.
Anchorage preparation in lower arch:
Class III elastics: level curve of Spee
High pull headgear
Vertical loops in mandibular archwire to
prevent space loss with class II elastics

ANCHORAGE IN FIXED
APPIANCES:
Anchorage conservation during treatment in
level anchorage system:
Delaying the extraction of maxillary
premolars
Upper anterior retraction: tying of first and
second molars ; palatal bar inserted


ANCHORAGE IN FIXED
APPIANCES:
ALEXANDER DISCIPLINE:
Vari-Simplex discipline
-6 degrees angulation of lower first molar
tubes for gain in arch length
‘Retractors’ ( Dr. Fred Schudy)
Cervical, combination or high pull
depending on growth pattern and control
needed

ANCHORAGE IN FIXED
APPIANCES:
Other intra oral appliances to control anchorage:
1. Transpalatal arch in
high angle cases with
high pull headgear
1. Nance holding arch
in class I cases with crowding;
preserves sagittal anchorage
and retards vertical eruption

ANCHORAGE IN FIXED
APPIANCES:
Other intra oral appliances to control anchorage:
4. Mandibular lingual arch: sagittal and transverse
control
5. Lip bumper:
- uprighting of mandibular first molars
- distal force on lower molars
- muscular anchorage

ANCHORAGE IN FIXED
APPLIANCES:
BURSTONE’S SEGMENTAL ARCH
TECHNIQUE:
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

ANCHORAGE IN FIXED
APPLIANCES:
Anterior retraction: group A arches:
(AJO 1982)
Buccal stabilizing segment with a transpalatal
arch in maxilla and lingual arch in mandible:
posterior anchorage unit
Anterior segment
Two tooth concept:
large distance b/w canine
and molar;
low load- deflection rates

ANCHORAGE IN FIXED
APPLIANCES:
En masse controlled tipping followed by en
masse root movement
TMA 0.018 loop welded to 00.017 by 0.025
base arch
- magnitude of moment
on molar increases due
to additional wire
in the loop
- low load deflection rate

ANCHORAGE IN FIXED
APPLIANCES:
Heavy base arch withstands the higher
moments without permanent deformation
Spring is positioned mesially
Posterior tipping of buccal segments along
with TPA and consolidation of posterior
teeth : anchorage reinforcement


ANCHORAGE IN FIXED
APPLIANCES:
Group B arches:
M/F ratio needed = 10:1 for translation
Spring placed centrally b/w the two tubes
for same rate of change in M/F in both
alpha and beta moments


ANCHORAGE IN FIXED
APPLIANCES:
Group C arches:
Loop is positioned at 1/3 rd interbracket distance
from the molar tube
or
Symmetrically placed spring with Cl II or Cl III
elastics
Side effects: flaring of anteriors, vertical
extrusion of anteriors
Can be eliminated by using headgear to upper
arch

ANCHORAGE IN FIXED
APPLIANCES:
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


ANCHORAGE IN FIXED
APPLIANCES:
ROTH’S TECHNIQUE:
.022 slot
Double key hole loops used b/w lateral
and canine, and canine and premolar
- control canine rotation during extraction
space closure


ANCHORAGE IN FIXED
APPLIANCES:
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

ANCHORAGE IN FIXED
APPLIANCES:
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

ANCHORAGE IN FIXED
APPLIANCES:
Use of mandibular
lingual arch with finger
springs to widen premolar areas

Transpalatal bar:
intrusion of molars and
rotational control

ANCHORAGE IN FIXED
APPLIANCES:
Critical anchorage cases: Asher facebow
used to retract anteriors


ANCHORAGE IN FIXED
APPLIANCES:
BENNETT AND MCLAUGHLIN:
Anchorage control:
‘The manoeuvres 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.’


ANCHORAGE IN FIXED
APPLIANCES:
Anchorage control in the horizontal plane:
Inbuilt tip: proclination of anteriors
(especially uppers)
Elastic forces : anchorage loss,
distal rotation of anteriors,
bite deepening and increase
in curve of Spee


ANCHORAGE IN FIXED
APPLIANCES:
Control of anterior segment:
Lacebacks from most
distally banded molars
to canines

Bending the archwire back immediately
distal to the molar tube

ANCHORAGE IN FIXED
APPLIANCES:
Robinson in 1989:
- 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


ANCHORAGE IN FIXED
APPLIANCES:
Control of the posterior segments:
Greater need in upper arch:
- larger teeth
- greater tip
- more torque control and bodily movement
- upper molars move mesially more readily
- greater number of class II cases
Headgears : cervical, combination and high pull
with long outer bow
Palatal bar

ANCHORAGE IN FIXED
APPLIANCES:
Control of posterior segments: lower arch
Soldered lingual arch
Severe anterior crowding cases: push coil
springs with class III elastics; reinforced
with upper palatal bar and high pull
headgear


ANCHORAGE IN FIXED
APPLIANCES:


ANCHORAGE IN FIXED
APPLIANCES:
Anchorage assessment in the vertical plane:
Incisor vertical control: temporary
increases in overbite


ANCHORAGE IN FIXED
APPLIANCES:
Avoid bracketing incisors or avoid tying
the wire in the incisor brackets
Avoid early engagement of highly placed
canines


ANCHORAGE IN FIXED
APPLIANCES:
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


ANCHORAGE IN FIXED
APPLIANCES:
Palatal bars lie away from palate by 2mm:
vertical intrusive effect of the tongue
Avoid cervical pull headgear
(combination pull or high pull)
Upper or lower posterior biteplates


ANCHORAGE IN FIXED
APPLIANCES:
Anchorage assessment in the lateral plane:
Intercanine width maintained: avoid
uncontrolled expansion
Molar crossbites: bodily correction to
avoid overhanging palatal cusps


ANCHORAGE IN FIXED
APPLIANCES:
INVERSE ANCHORAGE TECHNIQUE:
Jose Carriere- 1991
Mandible is a preferred point of reference for diagnosis
and treatment planning, while maxilla is better suited to
adapting orthodontic correction
- maxilla is anatomically a more stable reference than
mandible
- functionally mandible is the center of convergence of
force vectors, while maxilla is less influenced by forces

ANCHORAGE IN FIXED
APPLIANCES:
- histological difference between maxilla
and mandible ; maxilla has more plasticity
of response
Treatment starts from the distal segments
and moves towards the mesial part
sectionally ( distomesial sequence)


ANCHORAGE IN FIXED
APPLIANCES:
Inverse anchorage equation:
C - Dc/2 – R1 = 0 where,
C= horizontal distance b/w the vertical line
passing through the cusp tip of the upper canine
and the vertical line passing through the posterior
end of the distal ridge of the lower canine
Dc= arch length discrepancy of the mandibular
arch, measured from distal of both lower canines
R1= amount in mm which the anterior limit of the
lower incisors should be moved in the ceph for the
correction of a case

ANCHORAGE IN FIXED
APPLIANCES:
Stages:
Maxillary stage:
treatment started in the maxilla with
posterior leveling, canine retraction,
anterior leveling and anterior retraction
Mandibular stage:
same sequence

Class II Div 1


Other anchorage reinforcements used:
- lingual arch, labial arch and transpalatal
arch
- extraoral anchorage with Cl III elastics


ANCHORAGE IN FIXED
APPLIANCES:
BEGG TECHNIQUE:
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

ANCHORAGE IN FIXED
APPLIANCES:
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.”

ANCHORAGE IN FIXED
APPLIANCES:
Experiment using cuspid retraction spring:
Free crown tipping retraction of cuspid
and bodily movement anchorage
resistance by molar and bicuspid


ANCHORAGE IN FIXED
APPLIANCES:
Optimal force range for moving canines
distally: 150-200 gm.
Further increase of force reduced the
canine movement till it approached zero
Movement of molar unit occurred with
force values of 300-500 gm.
Therefore, use of light differential forces
in Begg technique

ANCHORAGE IN FIXED
APPLIANCES:
Anchorage considerations in stage I:
1. Sagittal: Upper molar anchorage:
- upper Cl I elastics not used
- TPA , when using power arms and palatal
elastics ( also consolidating the first and
second molars)


ANCHORAGE IN FIXED
APPLIANCES:
Anchorage considerations in stage I:
1. Sagittal: lower molar anchorage:
- stiff lower wire ( 0.018” P or P+)
- light (yellow or road runner) elastics
- molar stop in case of Cl II and lower Cl I
elastics
- lip bumper in critical anchorage cases

ANCHORAGE IN FIXED
APPLIANCES:
Causes of anchorage loss in sagittal direction
in stage I:
Insufficient resistance from anchor bends
due to inadequate anchor bends or use of
flexible wires like NiTi and undersize or
multilooped SS wire
Excessively heavy
elastic pull

ANCHORAGE IN FIXED
APPLIANCES:
Causes of anchorage loss in sagittal direction in
stage I:
Increased resistance from anterior teeth:
- incisor and/ or canine roots touching labial
cortical plate
- abnormal tongue or lip function
- overjet reduction before overbite reduction
High mandibular plane angle with reduced
masticatory forces

ANCHORAGE IN FIXED
APPLIANCES:
Causes of anchorage loss in vertical direction in
stage I:
Extrusion of molars due
to the anchor bends

Vertical component
of Cl II elastics in lower
arch

ANCHORAGE IN FIXED
APPLIANCES:
Resistance to extrusion of upper molars by
masticatory forces in normal or low angle cases
In high angle cases, reinforcement with TPA
kept slightly away from palate
High pull headgear
Lower molars: light elastics with mild anchor
bends; posterior acrylic bite blocks or EVAA
appliance
Engagement of wire in first and second molars

ANCHORAGE IN FIXED
APPLIANCES:
Causes of anchorage loss in the transverse direction:
Anchor bends and Cl II elastics cause lingual
rolling of lower molars
Control of anchor loss:
Sufficiently stiff wires kept expanded
TPA or expanded headgear facebow or lip bumper


ANCHORAGE IN FIXED
APPLIANCES:
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 Cl I elastics
Mild anchor bends to maintain over bite
correction

ANCHORAGE IN FIXED
APPLIANCES:
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

ANCHORAGE IN FIXED
APPLIANCES:
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

ANCHORAGE IN FIXED
APPLIANCES:
Causes of anchorage loss in stage III:
Torquing auxiliaries and uprighting springs cause
reciprocal reactions in all three planes of space:
- lingual root torquing and distal root uprighting:
labial crown movements, extrusion of anteriors and
intrusion of posteriors, buccal crown movement of
posteriors
- reverse effects for labial root
torquing and mesial root
movements

ANCHORAGE IN FIXED
APPLIANCES:
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 P)
Lighter auxiliaries and uprighting springs
Light Cl II elastics

ANCHORAGE IN FIXED
APPLIANCES:
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

ANCHORAGE IN FIXED
APPLIANCES:
Reinforcement of anchorage:
3. Transverse:
- contraction and toe-in in heavy base
wires
- TPA or overlay wires
- molar torquing auxiliary for buccal root
torque

ANCHORAGE IN FIXED
APPLIANCES:
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
Use of lighter auxiliaries and springs ( 0.009,
0.010, 0.012 as opposed to 0.014 and 0.016)

ANCHORAGE IN FIXED
APPLIANCES:
DIFFERENTIAL STRAIGHT ARCH
TECHNIQUE: TIP-EDGE
Peter Kesling
0.022 by 0.028 slot size with increase to 0.028
Vertical slot for placement of auxiliaries
Finishing possible with rectangular wires


ANCHORAGE IN FIXED
APPLIANCES:
ANCHORAGE IN FIXED FUNCTIONAL
APPLIANCES:
Herbst appliance:
- partial anchorage: maxilla:
first permanent molars and first premolars are
banded and connected with a lingual or buccal
sectional wire
mandible: first premolars are banded and
connected with a lingual sectional wire touching
anterior teeth

ANCHORAGE IN FIXED
APPLIANCES:
Partial anchorage


ANCHORAGE IN FIXED
APPLIANCES:
- total anchorage: maxilla:
labial arch wire attached to brackets on
premolars, canines and incisors
Mandible: lingual sectional arch wire
extended to permanent first molars
Bands are replaced by cast splints


ANCHORAGE IN FIXED
APPLIANCES:
total anchorage


ANCHORAGE IN FIXED
APPLIANCES:
Jasper jumper:


ANCHORAGE IN FIXED
APPLIANCES:
Jasper jumper:
Preparation of anchorage:
- full size arch wires cinched back at the
ends; inclusion of second molars
- anterior lingual crown torque in lower
wire
- TPA and lingual arch

ANCHORAGE IN FIXED
APPLIANCES:
Jasper jumper:
Expansion of molar area


IMPLANTS :
Boucher: Implants are alloplastic devices which
are surgically inserted into or onto jaw bone.
Anchorage source:
Orthopedic anchorage:
- maxillary expansion
- headgear like effects
Dental anchorage:
- space closure
- intrusion ( anterior and posterior)
- distalization

IMPLANTS :
Implant designs for orthodontic usage:
- onplant
- mini-implant
- impacted titanium post
- skeletal anchorage system


IMPLANTS :
Why implants?
Limitations of fixed orthodontic therapy:
Headgear compliance and safety
Reactive forces from dental anchors


IMPLANTS:
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

IMPLANTS:
Implants for skeletal expansion:
-Guyman (1980) intentionally ankylosed
maxillary permanent lateral incisors of
monkeys
No movement of
laterals during expansion


IMPLANTS:
Parr, Roberts, et al (1997):
Midnasal expansion using endosseous titanium
screws; Rabbit study
Stability of implants seen for 1N and 3N loading


IMPLANTS :
Implants for intrusion of teeth:
Creekmore ( 1983)
Vitallium implant for
anchorage while intruding
upper anterior teeth
6mm intrusion with
25degrees torque

IMPLANTS :
Southard (1995)
Comparison of intrusion
potential of titanium
implants and that of teeth
Titanium implants placed
in extracted 4th premolar
area of dogs
Intrusive force = 60gms

IMPLANTS :
Implants for space closure:
Linkow ( 1970): implanto-orthodontics


IMPLANTS :


IMPLANTS :
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

IMPLANTS :
Other implant designs:
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


IMPLANTS :
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

Molar connected to
implant with 0.040 ss
wire

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

Incisor intrusion:


Incisor intrusion

Cuspid retraction

Molar intrusion

IMPLANTS :
Skeletal anchorage system (SAS):
Sugawara and Umemori (1999)
Titanium miniplates
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 www.indiandentalacademy.com

ANCHORAGE IN FIXED
APPLIANCES:
Zygoma ligatures: Melsen et al JCO ’98
Anchorage for intrusion and retraction of maxillary
incisors in partially edentulous patients
Horizontal bony canal drilled 1cm lateral to alveolar
process with entrance and exit holes in superior
portion of infrazygomatic crest
Double twisted 0.012 ligature wire inserted through
the canal

ANCHORAGE IN FIXED
APPLIANCES:
Methods of anchorage conservation:
Transpalatal arch:
Introduced by Goshgarian
0.036 SS wire
Anchorage reinforcement
Other uses: distalization,
rotation, torque, expansion
or contraction, vertical control

ANCHORAGE IN FIXED
APPLIANCES:
Burstone : ( JCO ’88-’89)
use of 0.032 by 0.032 SS or TMA in
transpalatal arches depending on the passive
or active


ANCHORAGE IN FIXED
APPLIANCES:
Lip bumper:
Alters equilibrium b/w cheeks, lips and
tongue
Transmits forces from perioral muscles to
the lower molars
Can be used for distalization of molars
Attachment of Cl III elastics

ANCHORAGE IN FIXED
APPLIANCES:
Lingual arch:
Introduced by Hotz
0.036 SS wire
Loops mesial to the lower molars
Prevents mesial migration of molars
Can be used for gaining arch length
Springs soldered to lingual arches
for premolar movements

Thank you
Leader in continuing dental education


Anchorage in orthodontics /certified fixed orthodontic courses by Indian dental academy

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Anchorage in orthodontics /certified fixed orthodontic courses by Indian dental academy