Introduction: Coated archwires improve aesthetics during orthodontic treatment. However, little is known regarding
their clinical benefit. This randomised controlled trial (RCT) compared the tooth alignment (TA), coating loss (CL),
colour change (∆E*), and patient perception of coated archwires with their controls. Details of ∆E* and perception were reported in the second part of the articles. Methods: This RCT was done at three centres. Participants
were randomised to receive one of four treatment interventions using 0.014” superelastic coated nickel-titanium
archwires from Orthocare, RMO, G&H, and conventional uncoated 3M Unitek® archwires. These archwires were
ligated during bonding and collected after eighth week and questionnaires were distributed to participants in the
experimental groups only. After removal, TA and CL were measured using Little’s Irregularity Index and Autodesk®
AutoCAD® software, respectively. At the time of this preliminary reporting, 84 participants had completed the trial. Two archwires fractured and were excluded. Therefore, 166 archwires (n = 166) were analysed. Results: Only
non-extraction cases showed statistically significant differences in TA change between all groups (p = 0.005) and
RMO showed significantly lowest mean of TA (1.5 mm). RMO and Orthocare showed significant TA change in the
upper and lower arches (p = 0.037, 0.048). CL was found to be insignificant for both extraction and non-extraction
cases (p >0.05). Comparison between upper and lower arches revealed no significant difference in TA and CL in all
groups (p >0.05). Conclusion: From this preliminary analysis, Orthocare provides better TA in non-extraction cases
despite highest percentage of coating loss.
Introduction: Coated archwires improve aesthetics because of the tooth-coloured appearance. However, colour change of the coated archwires have been reported in vitro. Nonetheless, little is known to what extent this colour change occurs clinically. This second part of the multi-centre, double-blind, randomised controlled trial evaluated the colour change (E*) of three coated archwires with their controls and patient perception. Methods: 84 patients who received treatment with upper and lower fixed appliance treatment were invited. Consented patients were randomised to receive one of four treatment interventions using 0.014” superelastic nickel-titanium archwires from
(1) Orthocare (2) RMO (3) G&H, and (4) 3M Unitek® uncoated. These archwires were ligated during bonding and collected after 8th week. After removal, the digital images of the archwires were assessed for colour change using Adobe® Photoshop® software, and the CIE L*a*b* system was used to calculate the ΔE* values. Patient perception was measured using oral aesthetic subjective impact scale (OASIS) questionnaire. Results: For colour change and patient perception assessment, 132 archwires from 66 participants who had been treated with aesthetic archwires were collected. Two fractured archwires were excluded. Initial analysis revealed all three aesthetic archwires groups showed significant mean of E* with the highest was found in Orthocare (23.9), and the lowest is G&H (16.8). Post hoc comparison revealed statistically significant mean of E* in Orthocare when compared with other groups (p