Retention and relapse in orthodontics

1. Retention & relapse

2. Learning outcomes
1. Define Retention and Relapse in orthodontics
2. Describe the causesof relapse
3. Understand the need for retention
4. Discussvaries retentionhypothesis
5. Recognize length of retention period

3. Introduction
• RETAIN –means to “hold back or to hold secure”
• RELAPSE:“to slip or fall back to a former condition,
especially after improvement or seeming
improvement”

4. Why isRetention necessary ?
Proffit-
1. Reorganization of gingival and periodontal tissues
after orthodontic treatment.
2. Soft tissue pressure – relapse tendency.
3. Changes produced by growth may alter treatment
results.

5. Reorganization of gingival and periodontal tissues after
orthodontic treatment.
• Widening of pl space – disruption of fibers
• Teeth respond individually to forces of mastication
• Reorganization 3-4 months
• Slight mobility disappears

6. Failures in retention
– Failure to remove the cause of malocclusion.
– Incorrect diagnosis and treatment planning.
– Lack of normal cuspal interdigitation.
– Arch expansion.- Pre Rx arch dimensions to be
maintained
– Incorrect axial inclinations.
– Failure to manage rotations- over rotation
– Tooth size disharmony

7. Factors affecting type and length of retention
• How many teeth have been moved and how far.
• Occlusion and age of the patient.
• Cause of the particular malocclusion.
• Rapidity of corrections.
• Length of cusps/ relationship of the inclinedplanes.
• Health of the tissues involved.
• Arch harmony.
• Cell metabolism.
• Atmospheric pressure

8. Richard A Riedel – 1960
– Factors affecting retention
– 9Theorems
– Classified retention according to the requirements
of various types of cases.

9. Theorem -
1
Teeth that have been moved tend to return to
their former positions.
– Reasons :
• Musculature
• Apical base
• Transseptal fibers
• Bone morphology
General agreement over holding teeth in their corrected
positions

10. Elimination of the cause of Malocclusion will prevent
recurrence.
Habits, Tongue posture, mouth breathing
Theorem -
2

11. Malocclusion should be overcorrected as a safety factor
• Class II: edge-to-edge
• Class III
• Open bite
• Deep bite
• Expansion
• Rotations- provide space for eruption, surgical intervention
Theorem -
3

12. Proper occlusion is a potent factor in holding
teeth in their corrected positions.
– Maintain health of the periodontium.
– Functional occlusion.
Theorem -
4

13. Bone and adjacent tissues must be allowed time to
reorganize around newly positioned teeth
• Fixed retention
• No positive fixation- allow natural functioning
Theorem -
5

14. If the lower incisors are placed upright over basal bone,
they are more likely to remain in good alignment.
– Better the lingual than labial inclination.
– Secondary to maintaining arch form.
Theorem -
6

15. Corrections carried out during periods of
growth are less likely to relapse.
– Early treatment
– Importance of diagnosis and Rx planning.
– To attain proper muscle balance
Theorem -
7

16. The further teeth have been moved, the less
likelihood there is of relapse.
◊Questionable and not proven.
◊Guidance of eruption preferable.
Theorem -
8

17. Arch form, particularly in the mandibular arch, cannot
be permanently altered by appliance therapy.
Theorem -
9

18. Length of retention period
• No retention required
– Cross Bite (Anterior and posterior)
– Dentition treated with serial extraction
– correction achieved by retraction of maxillary
once the patients has completed growth
– dentitions in which teeth have been separated to
allow eruption of previously blocked out teeth

19. • Limited retention
– Class i non-extraction cases with spacing and
protrusion of maxillary incisors.
– Class i and II extraction cases
– Early correction of rotated teeth
– cases involve ectopic eruption or supernumerary
teeth
– Corrected deep bite
– Class II div II cases

20. • permanent or semi permanent retention
– expansion cases
– cases with generalized spacing
– sever rotation
– Midline diastema

21. RETAINERS
Retainer- An appliance usedto hold teeth in position after
orthodontic treatment.

22. Types of retainers

23. Reference for this lecture
1. 4rd edn .
Jeryl D.English. Mosby’s Orthodontic Review,
MOSBY’S
2. Endodontic-orthodontic relationships: a review of
Integrated treatment planning challenges (Hamilton and
Gutmann,1999)
3. Combined endodontic-orthodontic and prosthodontic
Treatment of fractured teeth. Case report (Kocadereli et
al.,1998)

24. THANK YOU
Q & A