Anchorage management in orthodontics

ANCHORAGE MANAGEMENT IN
ORTHODONTICS
Guided by
Prof.Dr.Raja A
Department of orthodontics
By
Ashok kumar A
II MDS
Department of orthodontics
Dr.Ashok kumar A - Orthodontics 1

C
O
N
T
E
N
T
S
 Introduction
 Definition
 Classification
 Sources of anchorage
 Anchorage savers
 Anchorage planning
 Anchorage loss
 Anchorage in different appliances & techniques
 Anchorage measure
 Conclusion
 References

INTRODUCTION
Anchorage is the word used in orthodontics to mean resistance to displacement .
• Newton's 3rd law of motion which states,'for every action,there is an equal and opposite reaction'
Tooth movement of the reactive member during Orthodontic Rx is termed as anchorage loss.
Active element - The active parts of the orthodontic appliance are concerned with tooth movements.
Reactive element - The resistance units provide anchorage that makes tooth movements possible.
• The aim of controlling orthodontic anchorage is to
resist these reactionary forces to minimize the
unwanted tooth movement and maximize the
desired tooth movements.

DEFINITION
• ln 1923, Louis Ottofy defined anchorage as ‘ base against which orthodontic force or
reaction of orthodontic force is applied '.
• Anchorage refers to the nature & degree of resistance to displacement offered
by an anatomic unit when used for the purpose of effecting tooth movement.
- GRABER
• The amount of movement of posterior teeth (molars, premolars) to close
the extraction space in order to achieve selected treatment goals .
- NANDA

CLASSIFICATION OF ANCHORAGE
MOYERS CLASSIFICATION
(1) Manner of force application
Reciprocal Simple
Stationary
(2) Jaws involved
Intramaxillary Intermaxillary
Either of the
jaws
Both the jaws
(Bakers anchorage 1904)
Moyers RE. Force Systems And Tissue Responses To Forces In Orthodontics: Hand Book Of Orthodontics. 4th Edition

(3) Site of anchorage
Intraoral
Extraoral
Teeth,
alveolar
bone,
palate
Cervical,
parietal,
occipital,
frontal and
symphysis
Muscular
Vestibular
shield, lip
bumper
(4) Number of anchorage units
Simple Reinforced
Compound
Moyers RE. Force Systems And Tissue Responses To Forces In Orthodontics: Hand Book Of Orthodontics. 4th Edition
Single tooth of
Greater alveolar
support against
single lesser
support
More than one
tooth of Greater
alveolar support
against group of
lesser support
More than
one resistant
unit are
utilized

SOURCES OF ANCHORAGE

Root form or shape Size and number of roots Position of the tooth
Inclination of the tooth Ankylosed teeth Intercuspation and contact points
INTRA ORAL SOURCE

Alveolar bone Basal bone Musculature
EXTRAORAL
SOURCES
INTRAORAL
SOURCES
Cranium bones Facial bones

MARCOTTE AND BURSTONE CLASSIFICATION (1990)
& NANDA
Burstone CJ. En Masse Space Closure. In Modern
Edgewise Mechanics And The Segmented Arch Technique.
Glendore: Ormco Corp; 1995: 50–60.
 A anchorage: critical / severe
 B anchorage: moderate
 C anchorage: mild / non critical
 Maximum Anchorage
 Moderate Anchorage
 Minimum Anchorage
CLASSIFICATION BY GIANELLY AND GOLDMAN (1971)
Group –D
Absolute Anchorage
SAS/TADs

• Tooth movement increases as pressure increases up to a point, remains at about the same level over a broad range,
and then may actually decline with extremely heavy pressure.
• The best definition of the optimum force for orthodontic purposes is the lightest force that produces a maximum
or near-maximum response. The magnitude of the optimum force will vary, depending on the way it is distributed
in the PDL (i.e.,it is different for different types of tooth movement [tipping,bodily movement,intrusion,and so on]).
Contemporary Orthodontics – WILLIAM R. PROFIT 6 th EDITION
• Pressure in the PDL is determined by the
force applied to a tooth divided by the area of
the PDL over which that force is distributed.

• In the first case (A1–M1), the pressure for the teeth to be moved is optimal, whereas the pressure in the anchor unit
is suboptimal, and the anchor teeth move less (anchorage is preserved).
• In the second case (A2–M2), although the pressure for the anchor teeth is less than for the teeth to be moved, both
are on the plateau of the pressure– response curve, and the anchor teeth can be expected to move as much as the
teeth that are desired to move (anchorage is lost).
• With extremely high force (A3–M3), the anchor teeth might move more than the teeth it was desired to move.
• Principle -Efficacy of light forces in controlling anchorage, & why heavy force destroys anchorage.

ANCHORAGE LOSS
SAGITTAL PLANE:
 Mesial movement of molars
 Proclination of anteriors
VERTICAL PLANE:
 Extrusion of molars
 Bite deepening due to anterior extrusion
TRANSVERSE PLANE
 Buccal flaring due to over expanded arch form and unintentional lingual root torque.
 Lingual dumping of molars
Geron S, Shpack N, Kandos S, Davidovitch M, Vardimon. Anchorage Loss-A Multifactorial Response.
Angle Orthod. 2003; 73(6): 730–7.

Causes of anchorage loss
1. Not wearing the appliance adequately.
2. Too much activation of springs or active components
3. Presence of acrylic or any obstruction on the path of tooth movement
4. Poor retention of appliance & Poor anchorage planning.
5. Anchor root area not sufficiently greater than the root area of tooth or teeth to be moved.
6. If appliance encourage tipping movement of anchor teeth and bodily movement of the
teeth to be moved.
7. Using heavy force in moving teeth.

ANCHORAGE PLANNING
• The number of teeth to be moved
• The type of teeth being moved
• Type of tooth movement
• Craniofacial pattern
• Periodontal condition
• Duration of tooth movement
• Anchorage value Freeman’s anchorage value diagram

Root surface
areas for the
permanent
dentition
(excluding 3rd
molars).
2nd molars are not included-space closure will occur
by the first permanent molars moving mesially.
2nd molars are not included - then space closure will occur equally from
the posterior teeth moving mesially and the anterior teeth moving distally.
2nd molar is included-Anchorage balance will be shifted to favour distal
movement of the anterior teeth.

ANCHORAGE SAVERS
REINFORCEMENT OF ANCHORAGE
Including as many teeth as possible in the anchorage unit. Ratio of PDL area of anchor unit to PDL area
of tooth movement unit - 2:1 without friction & 4:1 with friction
SUBDIVISION OF DESIRED TOOTH MOVEMENT
A common way to improve anchorage control is to pit the resistance of a group of teeth against the
movement of a single tooth rather than dividing the arch into less equal segments e.g. to reduce strain on
posterior anchorage – retraction of canine individually can be done .
TIPPING /UPRIGHTING
Tip the teeth and then upright them rather than moving them bodily.

FRICTION AND ANCHORAGE CONTROL STRATEGIES
• One step space closure with a frictionless appliance
• Tweed technique – sliding the canine  retract incisors
• Two step closure – tipping  upright
CORTICALANCHORAGE
• Cortical bone is more resistant to resorption; tooth movement is slowed when root contacts it.
• Torquing the roots of posterior teeth outward against the cortical plate inhibits the mesial movement
when extraction spaces are to be closed.

TRANSPALATAL ARCH
• Maintain arch width & molar position after buccal expansion
• Prevent buccal tipping in response to forces from an occipital
pull face bow head gear
LINGUALARCH
• Maintains arch width and length
• Align labial segment – prevents posterior teeth
mesial movement

NANCE HOLDING
ARCH
CLASS II ELASTICS LIP BUMPER
• Maintain maxillary arch length
• Used as an anchorage saver
during levelling, alignment &
canine retraction
• Intermaxillary Anchorage
• Angle called ideal force
• Patient compliance - limited
• Exerts distal force on molar from
lip pressure so maintains arch
length and anchorage potential of
lower molars
Fields HW. Treatment Of Orthodontic Problems In Preadolescent Children. In: Proffit WR, Fields HW. Contemporary Orthodontics. 3rd Ed.

DIFFERENTIAL FORCE
• The term “differential forces” is used to describe a biomechanical design of a force system which, by the
way of its application, is able to distribute the reciprocal forces over significantly different root areas
with the objective of eliciting a differential response.
• Eg - combination of closing loops for upper incisor retraction along with the application of Class II
elastics, thereby increasing the retraction force as compared to the anterior force felt by the upper molars.
DIFFERENTIAL MOMENTS
• Created by placing a bend on a wire between two brackets or groups of teeth.
• The bracket or tooth closer to the bend will have a greater
moment, and this can in many ways be used to augment anchorage.
Nanda R. Dr. Ravindra Nanda on orthodontic mechanics. Interview by Robert G Keim.
J Clin Orthod. 2010;44(5):293-302 Dr.Ashok kumar A - Orthodontics 21

SKELETALANCHORAGE
The anchorage derived from implants is categorized into:
1. Direct anchorage – when the tooth or teeth to be moved are attached directly to the bone anchor
2. Indirect anchorage - when another tooth or teeth are attached to the bone anchor to hold them in
position while they serve as anchorage
Creekmore et al. Possibility Of Skeletal Anchorage. J Clin Orthod. 1983; 4(4):26669
Types of anchorage devices
Endosseous implants
Surgical miniplates
Minniscrew implants

Endosseous implants
• These osseointegrated implants are modified forms of conventional dental implants -placed in the
palate, retromolar area and the area of absent or missing teeth -withstand more force than
mechanically retentive implants.
• Such implants were earlier used in the palate for intraoral molar distalisation
Drawbacks
• Waiting period before loading,
• Limitation in the area of placement because of their relatively large size,
• Cost, extensive surgical procedure required in the placement and difficulty in removal.

Skeletal anchorage system
(SAS) - Sugawara
• Bone repositioning and growth modification can be achieved by miniplates as they transfer the
orthopedic forces directly to the facial skeleton, leading to a reduction in unwanted side effects .
• Non-extraction treatment approach for some severe malocclusions like maxillary or mandibular
protrusion,a non-surgical orthodontic treatment option to correct skeletal malocclusions(surgical),
anterior crowding in adult patients, retreatment cases, correct minor surgical inaccuracies and relapse
tendencies after orthognathic surgery .

Miniscrew implants (MSIs)
• Mechanically retentive MSIs can provide absolute anchorage in orthodontics for a short duration. MSIs are
commercially available in the screw diameter range of 1.2-2.7 mm and length varying from 4 to 12 mm.
• The most common site for their placement is the inter-radicular bone between the teeth & now as newer advances
extraradicular placement in infrazygomatic crest and the mandibular buccal shelf are also used because of,
less risk of damaging roots ,do not interfere with mesiodistal movement of teeth or groups of teeth & low failure
percentage, if compared to the conventional mini-implants.

ANCHORAGE IN DIFFERENT
APPLIANCE SYSTEMS

REMOVABLE FUNCTIONAL APPLIANCE
Base Plate Point of attachment for the active components.
Distribute reactionary forces to the teeth and tissues.
Labial Bow Prevents the proclination of incisors which aids in the
stationary anchorage
TOOTH BORNE APPLIANCES : Activator, Bionator, Twin block
 Capping of incisal margins of lower incisors
 Proper fit of cusps of teeth into acrylic
 Deciduous molars used as anchors
 Edentulous areas after premature loss of deciduous molars
TISSUE BORNE APPLIANCES: Vestibular screen, Frankel function regulator
 Extention of acrylic into the vestibule , Head gears can be used as adjuncts .

FIXED FUNCTIONAL APPLIANCE
PARTIALANCHORAGE  Maxilla - 1st premolars and permanent 1st molars are
interconnected on each side. In mandibular arch the 1st premolar bands are connected.
TOTALANCHORAGE  Maxillary arch - labial sectional wire is placed in the
brackets of premolars, canines, incisors. In the mandibular arch lingual sectional wire
is extended to 1st permanent molars which are banded
SPLINT ANCHORAGE  In the deciduous and mixed dentition period bonded
type of herbst is used because of absence of 1st premolars.
PELLOT ANCHORAGE  Mandibular arch with the lingual arch wires acrylic
pellot is fabricated and fixed touching the lingual mucosa about 3mm below the
gingival margin.

EDGEWISE APPLIANCE

• The degree of tip-back on the terminal molars should be such that when the arch wire is placed in the buccal tubes,
it will cross the cuspid teeth at their DEJ (the tip usually varies from 15-30 degree).
• After placing the archwire in the molar tubes of the terminal molars, when it is raised and ligated to the brackets on
the 1st molar teeth, the mesial cusps of the terminal molars are elevated, and the 1st molars are depressed.
• When the archwire is engaged in the 2nd PM brackets, first molars are elevated and the 2nd PM are depressed.
• When canines are engaged, it is depressed, and the 1st premolars are elevated. Thus all the distal tipping forces on
premolars and molars are neutralised by the depressing force on the canines .
• When the archwire is ligated to the incisors, the action is the elevation of the canines and depression of the incisors.

• Cuspids & incisors react as a single unit to resist the depressing action of the distal tipping of the terminal molars.
• If the archwires are left in the mouth for a long period, the end result will be anterior open bite. In case of alteration
of occlusal plane, use the anterior box elastics.
• When class III elastics are applied along with anterior box elastics, the crowns of the mandibular buccal segment tip
distally to the desired degree of anchorage preparation with a minimum amount of mesial root displacement.
• Class III elastics facilitate mandibular anchorage and counteract
the mesial force of the 2nd order bends on roots of buccal teeth.
• An intermediate pull headgear has to be worn in the maxillary
arch to counteract forces of class III elastics on maxillary molars

• The anchorage thus prepared in the mandibular arch is utilized for enhancing maxillary anchorage and
distal en masse movement of the maxillary arch.
• The mesial and bite opening forces of second order bends in the maxillary arch are neutralised with class
II elastics in day time from mandibular terminal molars to inter-maxillary hook at V bend of the
maxillary arch.
• The distalising forces of the class II elastics worn in daytime and head gear worn at night time
contributes to anchorage preparation and distal en mass movement of the maxillary arch converting a
class II molar buccal relations in to class I.
Anchorage preparation in the maxillary arch

FIRST DEGREE ANCHORAGE PREPARATION
Minimal anchorage preperation
• For cases with ANB – 0° - 4°, Good facial esthetics
• Total discrepancy within 10mm
• Mandibular terminal molar must be uprighted & maintained.
• The anchorage preparation consisted of inclining the terminal molars which are
angulated such that the direction of pull of the intermaxillary elastic force during
function will not exceed 90° when related to the long axis of these teeth

SECOND DEGREE PREPARATION
Moderate anchorage preparation
• ANB - > 4.5°, Class II profile (retrognathic mandible)
• Facial esthetics make it desirable to move point B anteriorly & point A posteriorly
• Mandibular terminal molars must be tipped distally more so that their distal marginal
ridges are at gum level.
With such an anchorage preparation the direction of pull from the Class II elastics would be
greater than 90° during function. Such a pull will further depress rather than elongate the
terminal molars.

THIRD DEGREE [TOTAL] ANCHORGE PREPARATION
• ANB doesn’t exceed 5° and Total discrepancy 14 to 20 mm,
• All the posterior teeth must be tipped distally anchorage preparation positions
• Distal marginal ridges of the terminal molars are below gum level
• The direclion of pull of the Class ll intermaxillary elastics when related to the long axes of the
terminal molars should be greater than 90 degrees during function, so that the terminal molars would
be further depressed rather than elongated .

BEGG TECHNIQUE

• Begg light wire appliance develops its total anchorage potential from with in the mouth.
• It is a perfect example of stationary anchorage
• Anchorage in the first place, through bodily control given
to anchor units with the help of anchor bend (tip-back
bend) and, the freedom to tilt offered to the units that are
to be moved and the light Differential forces employed.
Begg PR. Differential Force In Orthodontic Treatment. Am J Orthod. 1956; 42(7):481–510.

Anchorage Bend force in first stage and net distal movement of upper molar :
• Anchorage Bend tends to tip the molar roots forward and crown backward. Net effect of widespread
difference between the high resistance root tipping and the low resistance crown tipping leads to more
crown movement.
• If molar mesially inclined at commencement of treatment, net distal movement of crown to upright
position can be sig. for - class II correction and increase in arch length in nonextraction cases.
Anchorage Bend force in first stage with or without net distal movement of lower molars
• Lower molar crown also have tendency to tip back that can be controlled by varying the force of class II
elastics. 11/2 – 21/2 ounce (nonext.) crown may tip back more and root tip forward less.21/2 – 31/2
ounce (ext.) both crown and root may tip, up righting the tooth but imparting little orno distal tipping .

ANCHORAGE FOR RETRACTION
• After arch wire attached, Class II elastic between intermaxillary hook of upper arch wire and hook on
mesial end of lower molar tube , it will tend to pull molar forward and retract anteriors.
• Anchorage Bend counteracts mesial pull. If appropriate Anchorage Bend and elastics are used (proper
m/f) tooth lean upright, and if teeth move- teeth will move bodily. At the same time elastics retract
anteriors lingually by tipping .
Begg PR. Differential Force In Orthodontic Treatment.
Am J Orthod. 1956; 42(7):481–510.

REFINED BEGG
ANCHORAGE IN SAGITTAL DIRECTION
CAUSES:
 Insufficient resistance from anchor bends
 Excessively heavy elastic pull
 Increased resistance from anteriors
Anterior roots touching the labial cortical plate
Abnormal lip or tongue function
 High MP angle: weak masticatory forces
• TPA can be used to stabilize upper molars in
case class I elastics are used
• A stiff lower archwire must be used for lower
molar control
• Elastics used must be light or ultralight elastics
• Stops should be placed
• Lip bumper

ANCHORAGE IN VERTICAL DIRECTION
ANCHOR LOSS IS DUE TO
 Extrusion of molars due to anchor bends
 Vertical components of the elastics in the lower arch
• TPA
• Stiff archwires – adequately expanded
• Suitably expanded headgear face bow
• Lip bumper
ANCHORAGE IN TRANSVERSE DIRECTION
Can be minimized by
 TPA away from palate
 High pull headgear
 Mild anchor bends and elastics
 Posterior acrylic bite blocks
 First and second molar tubes
Refined for modern times - Dr.Vijay P Jayade

MBT TECHNIQUE

Anchorage in Horizontal plane
Control of anchorage in anterior segments
• Lace backs and bends backs – to prevent proclination of anterior teeth during levelling & aligning phase.
• Reduce the anchorage needs during leveling and aligning.
• Bracket design – reduced tip.
• Use of very light arch wire forces.
• Avoidance of elastic chain
Systemized orthodontic
treatment mechanics –
McLaughlin , Bennett,Trevisi

Control of anchorage in posterior segments
• A transpalatal arch can be used in moderate anchorage cases.
• The Nance holding arch can be used during leveling, aligning and canine retraction stages
• Head gear.
• Lingual holding arch & Class III elastics
Systemized orthodontic treatment mechanics –McLaughlin , Bennett,Trevisi

Vertical control of incisors
• Because of the tip built in the canine brackets a transient deepening of bite occurs in the initial
aligning and leveling phases.
• If canines are distally tipped , when arch wire is engaged in the canine slot it lies incisal to the
incisor bracket slots causing undesirable extrusion of incisors when the wire is fully engaged.
• This effect can be minimized by either
not encaging the wire in incisor brackets
or not bonding the incisors until canines
are uprighted and moved distally, under
the control of the lacebacks.

Vertical control of canines
• The unwanted effects of fully encaging the arch wire in the brackets of high labial canines may be
minimized by lightly tying the canines into the primary arch wire with elastics thread.
Vertical control of molars in high angle case
 Upper second molars not banded  To minimize extrusion
 Expansion  Bodily movement rather than tipping
 Palatal bar  2mm away from palate  Intrusive effect
 Combination pull or high pull headgear used
 Posterior biteplate

Control of anchorage in transverse plane
• Inter canine width should not be altered to great extent during the treatment
• Molar cross bites should be corrected by bodily movement of molars
• If maxilla is too narrow, early rapid expansion should be considered prior to leveling and
aligning. If adequate maxillary bone exists, a fixed quad helix expander is used.
• Minimal molar cross bites are usually corrected by using rectangular wires which are slightly
expanded from normal and which carry buccal root torque.

ANCHORAGE NEEDS OF A CASE
PIP – Planned incisor position
Class II/1 Class III
Class II/2
Bimaxillary retrusion
Bimaxillary protrusion
The anchorage control needs of a case, early in treatment, can be decided by comparing the starting
position of upper and lower incisors with PIP at the end of treatment

SEGMENTAL MECHANICS

ANCHORAGE UNITS
 Posterior units consists of buccal segments PM, I molar, II molar.
 Connected by TPA in the maxilla and Lingual arch in the mandible.
 Buccal stabilizing segments – 19x25 stainless steel
ANCHORAGE CONTROL
 Stress levels on the anchor unit should be kept low.
 Heavy rigid arch wire segments in anchor unit.
 Applying a moment for bodily control of anchor unit.
 Differential force system to control the moment to force system
Burstone CJ. The Segmented Arch Approach To Space Closure. Am J Orthod. 1982; 82(5):361-78.

Deep overbite correction
• Intrusion of anterior teeth
• Extrusion of posterior teeth
• Combination
VERTICAL CONTROL
• Buccal segment wire bent gingivally into a
small hook
• 0.018’’TMA can be welded mesial to the molar
• Omega loop – mesial to the first molar
• Washer can be crimped on the wire
SAGITTAL CONTROL

Group B anchorage
• Requires equal translation of the anterior &
posterior segments into the extraction space
• Equal and opposite forces and moments are
indicated
Group C anchorage
• Alpha moment > Beta moment
• Spring closure to the anterior segment
• Intermaxillary elastics & Protraction headgear
Group A anchorage
• Extra oral appliances
• Inter maxillary elastics
• Applying differential M/F ratio
• T- loop is placed in the center b/w ant. & post. attachments
SPACE CLOSURE
 Alpha or anterior moment
 Beta or posterior moment
 Horizontal force

ROTH PRESCRIPTION
He Provides over-corrected tooth positions prior to the appliance removal.
LEVELING AND ALIGNMENT:
 small flexible wire helps conserve anchorage.
 Small wires exert light forces on teeth and the overbite and occlusion hold the arches in the respective
positions and prevent forward migration.
LEVELING THE CURVE OF SPEE:
 Leveling with a continuous wire will lead to slippage of anchorage. This can be avoided by assessing
the incisor position and if permitted by intruding them.
ROTH RH. 5 Year Clinical Evaluation Of The Andrews Straight-Wire Appliance. J Clin Orthod. 1976; 10(11): 836-50.

RETRACTION OF THE CANINES AND INCISORS:
 Importance should be given to position of the anteriors.
 Retracting procumbent incisors using reciprocal forces burn up more anchorage
 Ascher’s face bow can be used for upto6-8 weeks
 Once incisors upright, they offer very little resistance as anchor unit and can be easily retracted.
COUNTER BUCCOLINGUAL TIP:
 Added only to the maxillary molar translation brackets.
 As the molar translates mesially during space closure, it tips buccally thus rendering the buccal
cusps more gingival to the palatal cusps.
 This effect is resolved by counter bucco-lingual tip feature in tube by placing buccal root torque.

Adjuncts used
• Head gear: Roth does not encourage prolonged use of head gear either for distalization or
for preventing forward migration of dentition. He states that the use of extra oral force can
be avoided by
a. Using small flexible wires for leveling and alignment
b. Bonding second molars at the onset of treatment
c. Leveling and curve of Spee using utility arches to intrude incisors.
• The Ascher’s face bow that he advocated connects directly to the anterior teeth, with a force
of12-15 ounces and the duration is kept to a minimum of 6-8weeks till the anterior upright.
• Roth also use the Goshgarian type TPA and lip bumper.

SAGITTAL CONTROL
 Second molar banding
 Upright anteriors - little resistance to lingual tipping
 Anterior face bow is used to retract the proclined
incisors
 Maximum anchorage – Asher face bow
 Moderate anchorage - Double key- hole loops
VERTICAL CONTROL
 Utility arches to intrude incisors
 Short intermaxillary elastics: 1/8’’, 4-8 Oz pull
– no extrusion of molars
 TRANSPALATAL ARCH: 6-8mm away from
the palate – intrusion of molars.

VARISIMPLEX TECHNIQUE
 Developed by Wick Alexander
 Used Single width brackets except u/incisors
 Increased interbracket distance leading to Lighter force delivery .
DRIFTODONTICS
 The mandibular anterior teeth drift distally and the mandibular posterior teeth drift mesially.
 Appliances are placed only on the maxillary arch until a class I cuspid relation is achieved.
 The late placement of mandibular appliance - Driftodontics.
ANCHORAGE CONSERVATION IN MANDIBLE
Mandibular molar has – 6 ° distal tip  promotes leveling and helps in gaining arch length (Tweed’s philosophy)
ANCHORAGE CONSERVATION IN MAXILLA
• Tying back of orthodontic wires
• Omega loops - Preferred method
• Arch wire bend backs Dr.Ashok kumar A - Orthodontics 57

HEADGEAR:
DIRECTION OF PULL AND INDICATION
FORCE AND TIME OF WEAR
Initially - 8 Oz , from next appointment – 16oz
ELASTICS
Anchorage considerations during elastic wear
 Elastics are not used until the patient is in finishing arch wires - 17x25 stainless steel in both arches
 Attached from the mandibular II molar to the hook on maxillary lateral incisor
Other Intra Oral Appliances
 Trans palatal arch
 Lower lingual arch
 Nance holding arch
Alexander RG. The Vari-Simplex Discipline. Part 1. Concept And Appliance Design.J Clin Orthod. 1983; 17(6):380-92

LEVELANCHORAGE SYSTEM
Integrated approach to orthodontic treatment.
• Detailed and carefully validated approach to Rx planning
• Pre adjusted edgewise appliance
• Preformed arch wires
• Step by step Rx procedure for ext. and non ext cases
• Timing chart, Self check chart
ANCHOR SAVER: Distal crown tip
Two choices of distal crown tip for the mandibular buccal teeth
• Regular series -10º,6º,4º
• Major Series -15º,10º,6º
RootTL.The level anchorage system for correction of orthodontic malocclusions
.Am J Orthod. 1981 Oct;80(4):395-410.

Bioprogressive therapy

Bioprogressive therapy given by Rickets includes
1. Stabilization of upper and lower molar according to grade of anchorage.
2. Retraction and uprighting cuspids with sectional mechanisms.
3. Retraction and consolidation of upper and lower incisors.
4. Continuous arches for details of ideal and finishing occlusion
UPPER LOWER
 Maximum anchorage
1. Buccal root torque (45º).
2. Expansion of molar section of 10mm on each side.
3. Tip back of 30º – 40º keeps the molar upright & resists the forward pull.
4. Distal molar rotation of 30º – 40º is also placed.
 Moderate anchorage: Contraction utility arch
 Minimum anchorage: Round wire in the molar tube.

SELF LIGATING SYSTEM
• Slide a tooth along a wire with very low friction and with no loss of control.
• Anchorage preservation is enhanced
• Rajcich and sadowsky (1997), that retraction of canines with sliding mechanics
when the molar is prevented from tipping or sliding mesially incurs impressively
low anchorage loss.
• A crimped stop or hook -controll molar tip and slide

LINGUAL ORTHODONTICS

Mechanics Used to Control Anchorage in the Upper Arch
• Mechanical advantages gained from lingual treatment are buccal root torque and distal rotation of the
molars, especially due to the easily established cortical bone anchorage
Maximum anchorage (upper arch)
• Helical loop and T-loop mechanics are combined with a transpalatal arch and a buccal sectional arch
from 1st to 2nd upper molars for stabilization. Also, high-pull headgear and Class II elastics are used.

MODERATE ANCHORAGE (UPPER ARCH)
• L-loop mechanics are combined with a transpalatal arch to prevent a
transverse bowing effect. The anterior segment (3|3) and the posterior
segment (7–5|5–7) are “figure eighted” with ligature wire.
• When a transpalatal arch cannot be used, sliding mechanics are used by
placing a power chain from the lingual of the canine to the lingual of the
second premolar in first premolar extraction cases.
• If the transverse bowing occurs, a power chain can be used from the lingual of
the canine to the buccal of the first molar to rotate the first molars mesially .

MINIMUM ANCHORAGE (UPPER ARCH)
• Extraction spaces are closed by a reciprocal elastic force, with a power chain placed on both the buccal
and lingual of the canine and first molar
• The anterior segment (usually 4|4) is “figure-eighted” with ligature wire. Frequently, cases requiring
minimum anchorage control are those in which 2nd PM have been extracted and mesial molar movement
is encouraged. Sometimes Class III elastics are used to enhance mesial movement of the molars.

MAXIMUM ANCHORAGE (LOWER ARCH)
• An elastic power chain is used on the lingual, with a buccal
sectional arch for stabilization.
• The anterior segment (3|3) and the posterior segment (7–5|5–7) is
“figure-eighted” with ligature wire. Class III elastics are used both
buccally and lingually for reinforced anchorage
MODERATE ANCHORAGE (LOWER ARCH)
• Sliding mechanics are used with reciprocal elastic forces (power
chains from 3-5 on both sides). The anterior segment (3|3) and the
posterior segment (7–5|5–7) are “figure-eighted” with ligature wire ,
buccal segmental wires are not needed.

MINIMUM ANCHORAGE (LOWER ARCH)
• An elastic power chain is placed circularly from the lingual of the first molar, encircling the canine,
and attaching to the buccal of the first molar. Class II elastics are used to facilitate mesial movement
of the molars. The anterior segment (4 |4) is “figure-eighted” with ligature wire. As the molars move
mesially, gingival recession over the mesial root of the first molar should be prevented

Anterior and Lateral Concerns
• The lingual appliance, due to the discomfort associated with tongue contact, redirects the tongue tip to
the palatal vault in speech and swallowing.
• Therefore, the anterior thrust component is eliminated, and normal muscle balance is restored .
A similar effect is seen with the use of lingual elastics. This has been termed the “fence effect” in that
the lingual appliance or the elastics create a fencing of the tongue musculature from the dentition.
• The lateral occlusion prevents the transverse bowing effect which is often seen during lingual
treatment. The anterior-posterior forces used for retraction should be light, minimizing anchorage loss
while maintaining lateral occlusal function.

• The use of micro-implants as a noncompliance method is very advisable in
patients when maximum anchorage is required (Kyung 2006 ).
• For anatomic reasons, the best place for them to be implanted is between the 1st
and 2nd molars or between the 2nd bicuspid and the first molar.
• It provide absolute anchorage without the cooperation of the patient in
conjunction with a controlled retraction mechanics & less lateral bowing effect.
• Another method to enhance anchorage is to bond a fixed retention wire on the
labial side of the second bicuspid, first and second molars.
• It is easy and comfortable for the patient and for the orthodontist, and it can be
used on the upper and lower arch

Alveolar Corticotomies and Anchorage

• (ACS) are defined as a surgical intervention limited to the cortical portion of the alveolar bone .
Indication
(1) To accelerate corrective orthodontic treatment, as a whole,
(2) To enhance the correction of moderate to severe skeletal malocclusions &
(3) To facilitate the implementation of mechanically challenging orthodontic movements .
• ACS are for cases where either skeletal anchorage devices (mini-implants and miniplates) cannot be
used, for anatomical or financial reasons or both (ACS and anchorage devices) can be used in
combination .

• This procedure was designed to take into account the law governing the difference in gradual movement
augmentation between the teeth which had been subjected to corticotomy & those which had not.
• This implies that decortication surgery triggers a substantial accelerated response in a limited area
following demineralization. As a result, tooth movements will occur more quickly in the group of
corticotomized teeth.
• This difference in gradual movement augmentation will contribute to modify the relative anchorage
between the teeth. In essence, anchorage teeth offer more effective anchorage if they are not
corticotomized whereas corticotomized teeth can be moved more easily.

PHARMACOLOGICAL MANAGEMENT OF ANCHORAGE
• Despite the efficacy of orthodontic techniques, there are a number of circumstances in which
treatment efficiency might be improved by modulating the activity of osteoclasts, and therefore,
bone turnover.
• Different drugs are able to alter the bone remodeling cycle, thus influencing tooth movement, as
shown in different experimental models.
• Local delivery - Several drugs that modify osteoclasts function, such as bisphosphonates (BPs),
anti-inflammatories and osteoprotegerin (OPG), have been used to prevent anchorage loss in
Orthodontics

Measuring anchorage
Lower incisor anteroposterior position
• A more labial position of the lower incisors at the end of tooth movement is conventionally
considered to represent loss of anchorage
• Cephalometric measures such as lower incisor to nasion-pogonion, or lower incisor inclination to
mandibular plane are used to assess this aspect of anchorage consumption/loss.
Balancing the books on orthodontic treatment: an integrated analysis of change
British Journal of Orthodontics 23: 93-102Johnston LE (1996)

PITCHFORK ANALYSIS
• This is a very well known form of superimposition on bony structures, described and popularised by
Lysle Johnston (1985, 1996). This reference structure is essentially the maxilla and zygoma.
• Johnston developed a comprehensive set of measures relative to a mean functional occlusal plane,
which provide a measure of anteroposterior movement of upper , lower incisors & molars and the
contributions of mandibular and maxillary growth.
• Limitation - Not provide full quantification of the anchorage work done (no measurement of changes in
incisor inclination or canine angulation .
Balancing the books on orthodontic treatment: an integrated analysis of change
British Journal of Orthodontics 23: 93-102Johnston LE (1996)

SUPERIMPOSITION ON OTHER CRANIAL STRUCTURES
• De Coster’s line in the cranial base and Bjork’s ‘stable’ structures in the maxilla and mandible.
Disadvantages in the pitchfork analysis -mannchen (2001)
1) The maxilla is not the best structure on which to superimpose, because rotational changes of the maxilla
during treatment will effect the resolved anteroposterior components.
2) The mean functional occlusal plane can also change & effect the measurements relative to it.
• Mannchen compared the results when the same cases were assessed using the pitchfork analysis and
Bjork’s structures.
• He found a tendency for the pitchfork to estimate more skeletal and less dental changes (approx 1 mm)
compared to using Bjork’s structures

Study model measurement
• There have been investigations of the suitability of the palatal rugae for superimposition of changes in
maxillary teeth.
• Hoggan and sadowsky (2001) reviewed some of the previous papers and carried out a study which
concluded that palatal rugae landmarks are as reliable as cephalometric structures for superimposition
• Ashmore et al (2002) have utilised different digitising techniques to measure molar movement in the
vertical and anteroposterior directions and concluded that superimposition on the palatal rugae was
sufficiently reliable to pursue as a method.
The use of palatal rugae for the assessment of anteroposterior tooth movements.
AJODO 119: 482-8Hoggan BR and Sadowsky C (2001)

CONCLUSION
 Anchorage should be of prime consideration before the treatment plan is formulated.
 The skeletal and dental anchorage should be judiciously planned for a better finish and
complete success in orthodontic therapy.
 To conclude the so called modern concept of anchorage involves the use of existing
anchorage, prepared anchorage, skeletal anchorage and reinforced anchorage.
 Proper diagnosis through recognition of anchorage availability must be made for better
finishing of the case .

REFERENCES
 Contemporary Orthodontics —William.R.Proffit – 6th edition.
 Handbook of orthodontics --Robert.E.Moyers —4th edition
 Textbook of orthodontics-- Amir.E. Bishara —1st edition
 Biomechanics in clinical Orthodontics Ravindra Nanda 1st edition
 Systemized orthodontic treatment mechanics Bennet McLaughlin Trevisi 1st edition
 Orthodontics- Current Principles & Techniques Graber, Vanarsdall, Vig- 4th edition
 Begg Orthodontic Theory and Technique P.R.Begg, P.C.Kesling 3rd edition
 Dentofacial orthopedics with functional appliances- Thomas.M.Graber, Thomas Rakosi, Alexandre.G. Pertovic -2nd edition.
 Refined begg for Modern times – Dr. Vijay P. Jayade

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