Conclusions
MINOR
All three retention strategies, a bonded retainer 13–23, a bonded retainer 12–22 and VFR, showed similar effectiveness in maintaining stability 1 year after the removal of the retention appliances. Even if minor changes occurred continuously, the overall increase in irregularity was clinically acceptable. However, from a stability perspective, a follow-up during 1 year is relatively short. Therefore, further evaluation of long-term stability is needed to make well-founded patient-care decisions.