An assessment of arch dimensional change with self-ligating brackets: systematic review and a randomised controlled trial.
Abstract
The purposes of this study were to systematically review the evidence on the clinical
use of self-ligating brackets (SLBs) and the validity of digital models, and to compare
maxillary arch dimensional change during alignment with conventional brackets (CBs)
and active or passive self-ligation in a clinical study.
In the systematic reviews, multiple databases were searched, study selection, quality
assessment and data extraction were performed, and meta-analyses conducted,
where appropriate. In a laboratory study a technique to measure molar inclination
change incorporating digital models was developed and validated. A multicentre, 3-
arm parallel-group trial was conducted with 96 patients aged 16 and above randomly
allocated into 3 equal groups (OvationTM, InOvationCTM or Damon QTM) and
undergoing alignment with a DamonTM wire sequence for at least 34 weeks.
Meta-analyses demonstrated no difference in arch dimensional changes between
SLBs and CBs; however, a greater treatment time was found with self-ligation (2.2
months, 95% CI: 0.4, 3.98). The validity of direct measurement on digital models was
confirmed in the other review, although meta-analysis was not possible. Complete data
were obtained from 87 subjects in the trial. Bracket type had no significant effect on
transverse dimensional changes with no difference in inter-molar width between
passive self-ligation and CBs (0.32mm, 95% CI: -0.41, 1.05, p= 0.38) or active selfligation
(0.4mm, 95% CI: -0.31, 1.11, p= 0.27). Incisor inclination changes with Damon
QTM could not be differentiated from the conventional system (0.44 degrees, 95% CI: -
1.93, 2.8, p=0.71) or InOvationCTM (-0.22 degrees, 95% CI: -2.58, 2.14, p=0.85).
Based on the systematic reviews, measurement of digital models is a valid alternative
to plaster models, while little evidence to support the use of self-ligation was found. In
the clinical trial no differences in arch dimensional changes during alignment between
CBs and either active or passive self-ligation was found.
Authors
Fleming, Padhraig SeamusCollections
- Theses [3303]