RETENTION – Period after active treatment when passive fixed / removable appliances were worn to stabilize the occlusion that had been created
—> appliance —>
RETAINER – Passive orthodontic appliances that help in maintaining and stabilizing the position of a single tooth or group of teeth to permit reorganizing of the supporting structures
WHY RETENTION IS NECESSARY?
- The gingival and periodontal tissues are affected by orthodontic tooth movement and require time for reorganization when the appliances are removed.
- The teeth be in an inherently unstable position after the treatment, so that soft tissue pressure constantly produce a relapse tendency.
- Changes produced by growth may alter the orthodontic treatment results.
Causes of Relapse
- Failure to remove cause of malocclusion
- Lack of normal cuspal interdigitation
- Incorrect axial inclination
- Tooth size disharmony and improper contacts
- Arch expansion
- Failure to manage rotations
|Time of usage||Cases|
|a. Cross bite
b. Dentition treated with serial extraction
|6 months =
|a. Class I non-extraction cases with spacing and protrusion of maxillary incisor
b. Class I and II extraction cases
c. Early correction of rotated teeth to their normal position before root completion
d. Cases involving ectopic eruption or the presence supernumerary teeth
e. Corrected deep bites
|a. After arch expansion especially in mandibular arch
b. Cases of considerable generalized spacing
c. Severe rotation or severe labiolingual malposition
d. Spacing between maxillary central incisor with an otherwise normal occlusion
Classification of Retainers
1. Fixed retainers -> cemented or bonded to the teeth
2. Removable retainers -> can be removed and reinserted by the patient
- With short labial bow
- With long labial bow
- With contoured labial bow
- Continuous labial bow soldered to clasps
Begg’s retainer (wrap-around retainer)
Kesling’s tooth positioner
Essix (vacuum-formed retainers)
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Gill, D.S. 2008. Orthodontics at a Glance. Blackwell Munksgaard.
Proffit, W.R; Field, H.W; Sarver, D.M. 2007. Contemporary of Orthodontics. 4th edition. St. Louis: Mosby Elvevier.
Singh, G. 2008. Textbook of Orthodontics. 2nd edition. New Delhi: Unipress.