the tweed profile - The Charles H. Tweed International Foundation

tooth alignment. Long term stability of a malocclusion
correction is an achievable goal.
CONCLUSIONS
The articles confirm some common findings. For
mean changes in arch width from each study, refer to
Table I and II.
1. In both extraction and non-extraction patients,
mandibular intercanine width increases during
treatment and decreases posttreatment.
2. Mandibular intermolar width changes are different
between the extraction and non-extraction
groups during treatment; the width decreases in
the extraction group and increases in the nonextraction
group.
3. Maxillary intercanine width increases during
treatment in both the extraction and non-extraction
cases.
4.
5.
6.
Maxillary intermolar width changes differently
between the extraction and non-extraction
groups during treatment; the width decreases in
the extraction group and increases in the nonextraction
group.
In various studies of non-extraction treatment with
distal movement of one or both arches, overall
long-term stability was achieved. According to
the articles, proper mechanics is required and
providing prolonged retention is suggested.
When evaluating premolar extraction treatment,
long-term stability turned out to be successfully
achieved even after the significant decrease in
arch width in the premolar and molar regions
and the subsequent decrease in intercanine width
posttreatment. The success is due to evidence
based treatment objectives and the clinicians’
diagnostic and treatment ability.
23