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2. Anchorage in Orthodontics
• Dr .Md Sazal Dewan
• Internee Doctor
• Dept.of orthodontics and dentofacial
orthopedics
• Update dental college and hospitals

3. Introduction
• Anchorage in orthodontics as the nature and
degree of resistance to displacement offered
by an anatomic unit for the purpose of
effecting tooth movement .(Graber)
• According to white and gardiner “anchorage is
the site of delivery from which a force is
exerted”.

4. Classification:
• According to the manner of force of
application:
1. Simple anchorage
2. Stationary anchorage
3. Reciprocal anchorage

5. • According to jaw involved :
1. intra-maxillary
2. Inter-maxillary
• According to the number of anchorage unit:
1. Single or primary anchorage
2. Compound anchorage
3. Multiple or reinforced anchorage

6. • According to the site of anchorage :
1. Intraoral
2. Extraoral
3. Muscular

7. Intraoral anchorage:
1) Teeth
2) Alveolar bone
3) Basal bone
4) Musculature

8.  The teeth : the anchorage potential of teeth
depends on a number of factor such as -
Root form
Size and number of roots
Root length
Inclination of tooth
Ankylosed teeth

9. Alveolar bone :
• Alveolar bone resist tooth movement up to its
limit beyond that it allow tooth movement by
remodelling
• Healthy alveolar bone give more anchorage

10. Basal bone :
• Certain areas acts as resistance areas provides
good anchorage –hard palate ,lingual surface
of mandible

11. Musculature :
• Hypertonic labial musculature used for
anchorage in lip bumper .

12. Extraoral anchorage : the extraoral source of
anchorage includes –
1. Cranium (occipital or parital anchorage ) : anchorage
obtained from occipital or parital bone example :
headgear to restrict maxillary growth
2. Cervical : anchorage from cervical or neck region
example: cervical headgear
3. Facial bones : face mask used to protract maxilla take
anchorage from mandibular symphysis , reverse
headgear take anchorage from head and chin

13. HEADGEAR
CHIN CUP
CERVICAL
HEAD GEAR

14. Simple anchorage :
• Is the dental anchorage such that manner and
application of force is such that it tends to
change the axial inclination of the teeth
• The resistance of anchorage units to tipping is
used to move other teeth
• The combined root surface area of the
anchorage unit must be double to that of
teeth to be moved example: palataly
placed premolar is pushed in to the arch by
rest of the teeth as anchor units

16. Stationary anchorage :
• Manner and application of force tends to
displace the anchorage unit
• Resistance provided by the anchorage units is
against bodily movement (displacement)

17. Reciprocal anchorage :
• Resistance offered by two malposed units
when the application of two equal and
opposite forces tends to move each unit to a
more normal position example: closure of
midline diastema ,cross bite elastics expantion
appliances

18. Midline diastema closure

19. Intra maxillary anchorage:
• Teeth are to be moved and the anchorage
units are in the same arch

20. Inter maxillary anchorage:
• Teeth are to be moved in one arch and
resistance units in opposite arch
• Example: class 2 and class 3 elastics

21. Single or primary anchorage:
• Single teeth with more alveolar support used
to move one with lesser support

22. Compound anchorage:
• Anchorage provides by more than one teeth
with great support to move tooth with less
support

23. Reinforced anchorage:
• More than one type of resistance unit is
utilized
• Example: 1) to augment the intra oral
anchorage ,extra oral anchorages trans
palatal arch and lingual arches are used
2)Upper anterior inclined plane used for
forward movement of mandible uses
muscular anchorages.

24. Upper inclined
plane

25. Mini dental implants:
• Used in patients having multiple lost teeth or
hypodontia or to augment teeth with
periodontal diseases .
 Classification:
According to exposure of head-
1. Open –head is exposed to oral cavity –used
when soft tissues are not movable
2. Closed-embedded under soft tissues-
movable tissues

26. Mini dental implant

27. According to implant placement:
1. Self tapping method :implant tapped in to a
previously drilled hole –smaller diameter
implants
2. Self drilling method: implants itself drilled
into the bone-larger diameter implant
 According to path of insertion:
1. Oblique :30 to 60 degrees to long axis of
teeth
2. Perpendicular :inserted perpendicular to the
bone surface

28. Causes of loss of anchorage :
Not wearing the appliance adequately
Too much activation of springs or active
components
Presence of acrylic or any obstruction on the
path of tooth movement
Poor retention of appliaces
Anterior bite plane: as this withdraws the
occlusal interlock

29. • Continued……..
Anchor root area not sufficiently greater than
the root area of tooth or teeth to be moved
If appliance encourage tipping movement of
anchor teeth and bodily movement of the
teeth to be moved

30. Prevention of anchorage loss:
By moving minimum number of teeth at a
time and using maximum number of teeth for
anchorage
By using gentle force ,30 to 50 grams per
single rooted tooth
By perfect fitting of the appliaces around all
the anchor teeth
By taking the advantage of the principle of
reciprocal movement, whenever possible

31.  Continued…….
By encouraging the patient to wear appliance
adequately
If above measures are found inadequate, the
anchorage may be reinforced by extra oral or
inter-maxillary traction

32. Conclusion:
• To ensure optimal treatment of patients ,it is
important for clinicians to continue learning
and to keep up with advances as the field
progresses as a whole to ensure that all
orthodontic patient are treated to the optimal
standard of care

33. • References
• aa (1994-01-01). By Ravindra Nanda – Temporary Anchorage Devices in Orthodontics (23379th ed.).
Elsevier Health Sciences.
• Prezzano, Wilbur J. (1951-09-01). "Anchorage and the mandibular arch". American Journal of
Orthodontics. 37 (9): 688–697. doi:10.1016/0002-9416(51)90180-7.
• Rachala, Madhukar Reddy (2011-12-12). Microimplants in Orthodontics: Temporary Anchorage
Device. S.l.: LAP LAMBERT Academic Publishing. ISBN 9783847312062.
• Roberts-Harry, D.; Sandy, J. (2004-03-13). "Orthodontics. Part 9: Anchorage control and distal
movement". British Dental Journal. 196 (5): 255–263. ISSN 0007-0610. doi:10.1038/sj.bdj.4811031.
• Nanda, Ravindra (2005-04-12). Biomechanics and Esthetic Strategies in Clinical Orthodontics.
Elsevier Health Sciences. ISBN 1455726117.
• Wehrbein, Heiner; Göllner, Peter (2007-11-01). "Skeletal anchorage in orthodontics--basics and
clinical application". Journal of Orofacial Orthopedics = Fortschritte Der Kieferorthopädie:
Organ/Official Journal Deutsche Gesellschaft Für Kieferorthopädie. 68 (6): 443–461. ISSN 1434-
5293. PMID 18034286. doi:10.1007/s00056-007-0725-y.
• "The effectiveness of cortical anchorage in patients treated with Class II elastics: Gary Pulsipher
Department of Orthodontics, University of Illinois, 1991". American Journal of Orthodontics and
Dentofacial Orthopedics. 102 (1): 97. 1992-07-01. doi:10.1016/S0889-5406(05)80990-4.