Evaluation and comparison of microbial colonization on nickel titanium (NiTi) closed coil springs and active tie-backs during orthodontic space closure: An study.

Objective: Literature suggests that the mode of ligation and use of elastomeric chains for achieving orthodontic space closure may result in a significant increase in microbial colonisation. The objective of the present study was to evaluate and compare the rates of microbial colonization on nickel-titanium (NiTi) closed-coil springs and active tie-backs used for orthodontic space closure in the maxillary premolar extraction site.

Materials And Methods: Thirty-two participants, including 14 males and 18 females, were enrolled in the present split-mouth study. In Group I, NiTi closed-coil springs (Nitinol, 3M Unitek) were used, while in Group II, active tie-backs [stainless steel ligature wire (0.009') threaded through an elastic module (3M Unitek) were used. After a period of 3 weeks, the NiTi closed-coil springs and active tie-backs were carefully removed and transferred to brain heart infusion broth (BHI Broth). The BHI broth samples were then incubated and inoculated into different media, followed by sub-culturing with various specific media. The colony-forming unit per millilitre were measured using a colony counter (HiMedia Laboratories Private Limited, Mumbai, Maharashtra, India). Finally, the various isolated colonies were submitted for phenotypic characterization using BIOMÉRIEUX VITEK MS, an automated mass spectrometry microbial identification system based on proteomics-based detection.

Results: The observations made in the study suggested an increased number of microbial colonies in the NiTi closed-coil spring group (46437.50 ± 11848.34 CFU/mL) compared to the active tie-back group (31031.25 ± 8204.97 CFU/mL), with the difference being statistically highly significant ( < 0.000).

Conclusion: Based on the findings of the present study, it can be concluded that using active tie-backs resulted in significantly reduced pathogenic adherence compared to NiTi closed-coil springs. However, further research is necessary to validate these findings before active tie-backs can be recommended as a suitable means for orthodontic space closure, especially in patients with compromised oral hygiene due to any given reason.