EFFICACY OF TEMPORARY FIXED RETENTION FOLLOWING ...
EFFICACY OF TEMPORARY FIXED RETENTION FOLLOWING ...
EFFICACY OF TEMPORARY FIXED RETENTION FOLLOWING ...
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Conflicting evidence regarding third molar effects on posttreatment<br />
mandibular incisor crowding has previously been discussed. In an effort to<br />
negate any potential impact on stability, third molars are routinely extracted<br />
following orthodontic treatment. Retention, in these cases is kept in place until<br />
the problem of the third molars has been resolved (Rosenstein and Jacobsen<br />
1971).<br />
Overcorrection is another technique aimed at minimizing relapse of teeth.<br />
This is commonly considered during treatment of rotated teeth. The thought is<br />
that by over-rotating the offending tooth with the notion that the there will be<br />
some tendency for the tooth to rotate back towards its former position.<br />
However, there is little evidence to indicate that over rotation is successful in<br />
preventing this type of relapse (Riedel 1960; Edwards 1970) and the amount of<br />
overcorrection needed to achieve stability is unknown.<br />
Another treatment protocol involves the paralleling of tooth roots and<br />
evenly spacing them from each other during the finishing stages of orthodontic<br />
treatment. Rosenstein and Jacobson (1971) claim that if specific care is used to<br />
parallel the roots of the teeth adjacent to the extraction sites, then relapse<br />
becomes less of a problem. Based on clinical experience and research conducted<br />
on over 10,000 of his completed cases, Alexander (2008) contends that proper<br />
bracket placement will allow for proper root positioning, i.e., the roots of the<br />
anterior teeth should be divergent and the roots of teeth adjacent to extraction<br />
sites should be parallel to each other.<br />
Summary<br />
The current consensus regarding the retention of posttreatment results can<br />
be found in the six conclusions drawn by Blake and Bibby (1998) in their<br />
literature review of retention and stability:<br />
1. The patient’s pretreatment lower arch form should be maintained<br />
during orthodontic treatment as much as possible.<br />
2. Original lower intercanine width should be maintained as much as<br />
possible because expansion of lower intercanine width is the most<br />
predictable of all orthodontic relapse.<br />
3. Mandibular arch length decreases with time.<br />
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