Five-year postretention outcomes of three retention methods--a randomized controlled trial

Area of Science:

• Orthodontics
• Dental Materials Science

Background:

• Orthodontic treatment aims to correct malocclusions, necessitating effective post-treatment retention.
• Long-term stability of orthodontic results depends on the chosen retention method.

Purpose of the Study:

• To compare the long-term effectiveness of three different orthodontic retention strategies.
• To evaluate clinical outcomes 5 years or more after retention.

Main Methods:

• A randomized, prospective, single-center controlled trial involving 49 patients.
• Patients received one of three retention methods: removable vacuum-formed retainer (VFR) with bonded canine-to-canine retainer (V-CTC), VFR with lower anterior stripping (V-S), or prefabricated positioner (P).
• Measurements included Little's Irregularity Index (LII), intercanine/intermolar width, arch length, overbite, and overjet.

Main Results:

• No significant differences in maxillary or mandibular arch length, intermolar width, overbite, or overjet were found between the groups.
• A significant difference was observed between V-S and P groups in maxillary and mandibular LII and intercanine width.
• All three retention methods demonstrated comparable overall clinical stability.

Conclusions:

• The evaluated retention methods (V-CTC, V-S, P) yielded equally favorable clinical results.
• Long-term orthodontic stability can be achieved with various retention approaches.
• Further research in multicenter settings may enhance generalizability.