Abstract
BackgroundThis study aimed to compare the effectiveness of two different protocols of wearing vacuum-formed retainers (VFRs) with the standard protocol of wearing Hawley retainer in maintaining the results of orthodontic treatment.Material and MethodsThis single-blind randomized clinical trial consisted of 90 patients who finished orthodontic treatment at the Department of Orthodontics of Mashhad Dental School, and required removable retainers. The participants were randomly divided into 3 groups and received the following treatments. Group 1: Hawley retainers (4 months full-time and then night-only); group 2: VFR_4M (4 months full-time and then night-only); group 3: VFR_1W (1 week full-time and then night-only). The study models were prepared after debond and at 4 and 8 months later, and intercanine width, intermolar width, arch length and the Little’s irregularity index were compared between groups.ResultsNo significant differences were found in intercanine and intermolar widths between groups (P<05). Upper arch length was significantly lower in Hawley group than the two VFR groups (p<0.05), but lower arch length values were comparable. Upper irregularity index was significantly lower in two VFR groups compared to Hawley group (p<0.05), whereas in the lower jaw, only VFR_4M group showed significantly lower crowding than Hawley group (p<0.05).ConclusionsBoth retention regimens of VFRs were more effective than Hawley retainer in maintaining arch length and tooth alignment in the upper arch. For better incisor alignment in the lower jaw, the patients should be advocated to wear VFR 4 months full-time and then at night instead of wearing Hawley retainer. Key words:Essix, Hawley retainer, orthodontic treatment, retention, vacuum-formed retainer.
Highlights
The success of orthodontic treatment mainly depends on retaining the teeth in the corrected position after the debond appointment
No significant difference was found between the two measurements of the same examiner (p>0.05). -Intercanine width Table 2 presents the mean and standard deviation (SD) of intercanine width in three groups over the period of the experiment
Further analysis revealed that upper arch length was significantly lower in the Hawley group than the two vacuum-formed retainers (VFRs) groups. -The modified Little’s irregularity index The repeated measures analysis revealed significant differences in mandibular and maxillary incisor irregularity among the three retention groups and between the different retention intervals (P
Summary
The success of orthodontic treatment mainly depends on retaining the teeth in the corrected position after the debond appointment. Since the remodeling of periodontal fibers occurs during the first 3-4 months after appliance removal, full-time wear of VFRs for just 1 week seems to be not effective in preventing relapse in orthodontic patients. This randomized, prospective clinical trial was conducted to assess the efficacy of Hawley and VFRs (two different retention protocols) in maintaining arch form and tooth alignment after removal of orthodontic appliances. This study aimed to compare the effectiveness of two different protocols of wearing vacuum-formed retainers (VFRs) with the standard protocol of wearing Hawley retainer in maintaining the results of orthodontic treatment. For better incisor alignment in the lower jaw, the patients should be advocated to wear VFR 4 months full-time and at night instead of wearing Hawley retainer
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
