# Evaluation and Comparison of Rate of Canine Retraction Between Titanium Dioxide Nanocoated Stainless Steel Archwire Segments and Uncoated Stainless Steel Archwire Segments: An In Vivo Split Mouth Study

## TL;DR

This study found that titanium dioxide nanocoated archwires helped move canine teeth faster during orthodontic treatment compared to uncoated wires.

## Contribution

The study introduces the use of TiO₂ nanocoating on archwires to improve the rate of canine retraction in orthodontics.

## Key findings

- TiO₂ nanocoated archwire segments showed a statistically significantly higher rate of canine retraction.
- Significant differences were observed at the first, third, and fourth months of treatment.
- The beneficial effect of nanocoating became more pronounced as treatment progressed.

## Abstract

Objectives

Our objectives were to compare titanium dioxide (TiO₂) nanocoated stainless steel archwire segments with uncoated stainless steel archwire segments during individual canine retraction.

Materials and methods

A split-mouth study was carried out in vivo on 15 patients who needed bilateral maxillary canine retraction. One side of each patient's stainless steel archwire was coated with TiO₂ nanoparticles, while the other side was left untreated. Using nickel-titanium closed coil springs and 150 g of force, canine retraction was performed. Digital vernier calipers were used to take measurements at four-week intervals for 16 weeks.

Results

The rate of canine retraction was statistically significantly higher in the TiO₂ nanocoated archwire segments than in the untreated segments (p < 0.05). At the first, third, and fourth months in particular, significant differences were found (T1: p=0.021*, T3: p=0.021*, and T4: p=0.023*). There were no changes at baseline (T0: p=1.000) or during the second month (T2: p=0.126), suggesting that the beneficial effect of nanocoating became more pronounced as treatment progressed. Overall, the difference in total space closure was modest but statistically significant, with steady advancement of space closure over time.

Conclusion

TiO₂ nanocoating may enhance the efficiency of orthodontic tooth movement by reducing friction. In the present study, the nanocoated segment showed faster tooth movement compared to the uncoated segment.