Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 May 1;20(1):17.
doi: 10.1186/s40510-019-0270-4.

In Vitro Evaluation of Microbial Contamination and the Disinfecting Efficacy of Chlorhexidine on Orthodontic Brackets

Free PMC article

In Vitro Evaluation of Microbial Contamination and the Disinfecting Efficacy of Chlorhexidine on Orthodontic Brackets

P R Vivek Aithal et al. Prog Orthod. .
Free PMC article


Background: Contamination of orthodontic appliances is due to the unhygienic practices followed during manufacturing and packaging processes, which may lead to cross-contamination. Although literature has indicated the need for sterilization or disinfection of orthodontic appliances before using in the oral cavity, this is still not employed in routine clinical practice. In this view, the current study evaluates the bacterial load on orthodontic brackets along with the disinfecting efficacy of chlorhexidine.

Methods: A total of 140 brackets were obtained from four different manufacturers and divided into six groups: group 1 (American Orthodontics; n = 30), group 2 (3M Unitek; n = 30), group 3 (Ortho Organizers; n = 30), group 4 (China Dental Orthodontic; n = 30), group 5 (negative control; n = 10), and group 6 (positive control; n = 10). Various microbiological and biochemical tests were conducted on the brackets to detect the type and growth of bacteria. Brackets that showed microbial contamination were then subjected to disinfection using 0.01% and 2% chlorhexidine solutions.

Results: Microbial contamination was detected on brackets of all the four groups. Bacteria, including Staphylococcus aureus, S. epidermidis, Lactobacilli, Klebsiella pneumoniae, Bacillus licheniformis, and B. cereus, were identified in these groups. Upon disinfection with 0.01% chlorhexidine solution, brackets in group 2 displayed complete decontamination, while all brackets in the other groups containing gram-negative bacteria exhibited complete decontamination with 2% chlorhexidine.

Conclusion: Orthodontic brackets received from four manufacturers showed high bacterial contamination. Disinfecting ability of 2% chlorhexidine proved highly effective in destroying both gram-positive and gram-negative bacteria. Therefore, use of 2% chlorhexidine in clinical practice for the disinfection of orthodontic brackets is suggested, before placement in the oral cavity.

Keywords: Contamination; Disinfection; Microbiology; Orthodontic brackets; Product packaging.

Conflict of interest statement

Ethics approval and consent to participate

Study has been approved by Institutional Ethics Committee.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.


Fig. 1
Fig. 1
Orthodontic bracket kits. a American Orthodontics brackets. b 3M Unitek. c Ortho Organizers. d China Dental Orthodontic Brackets
Fig. 2
Fig. 2
One of the brackets (2nd tube from the left) showing microbial growth in the brain heart infusion broth


    1. Saad HS, Nidhal GH, A-GB H. Evaluation of microbial contamination of different orthodontic as received arch wires from manufacturers. Int J Med Res Health Sci. 2017;6:13–18.
    1. Dewhirst FE, Chen T, Izard J, Paster BJ, Tanner AC, Yu W-H, et al. The human oral microbiome. J Bacteriol. 2010;192:5002–5017. doi: 10.1128/JB.00542-10. - DOI - PMC - PubMed
    1. Kharod N, Hemanth M, Kabbur K, Sharmada B, Darsan J. Assessing microbial contamination of as received orthodontic brackets and wires-an in vitro study. Int J Adv Res. 2017;6:1572–1575.
    1. Purmal K, Chin S, Pinto J, Yin W-F, Chan K-G. Microbial contamination of orthodontic buccal tubes from manufacturers. Int J Mol Sci. 2010;11:3349–3356. doi: 10.3390/ijms11093349. - DOI - PMC - PubMed
    1. Morrison A, Conrod S. Dental burs and endodontic files: are routine sterilization procedures effective? J Can Dent Assoc. 2009;75:39. - PubMed

LinkOut - more resources