Antibacterial efficiency of acid caffeic nanoparticles based sanitizer on orthodontic retainers
European Journal of Prosthodontics and Restorative Dentistry (2026) 34, 121-128
KeywordsOrthodontic retainer, Caffeic-acid nanoparticles, Control release, Drug delivery system.
Authorsmethodscould allow the build-up of bacteria on orthodontic retainers, which may cause severe periodontal diseases. Synthetic chemical compounds were used to sanitize the oral retainers; however, some of these compounds are not safe for human consumption. This study was aimed to develop a caffeic acid (CA) nanoparticle-based sanitizer for orthodontic retainers, that could overcome major oral infections in orthodontic retainer users. Polyvinyl alcohol (PVA) was used to create CA nanoparticles as an encapsulant. The nanoparticles were characterized using several spectroscopy approaches. The in vitro drug release behaviour, in addition to the assessment of its antibacterial activity on oral pathogens, was also studied. On average, the size of the nanoparticle was 133nm, with a surface charge of -11.70mV. Fourier-transform infrared spectroscopy spectra have revealed successful encapsulation of CA into PVA nanoparticles. On the CA release test, it reaches a plateau phase at 24 h, with a total release of 158.86 µg/mL from the nanoparticles. This steady and gradual drug release behaviour is desirable. On the Kirby Bauer assay, broad spectrum antibacterial activity was demonstrated by CA nanoparticles. Staphylococcus aureus demonstrated the lowest minimal inhibitory concentration and minimal bactericidal concentration. By immersing the Essix orthodontic retainer in the nanoparticle solution prior to the test, the load of S. aureus was reduced by 71.5% relative to growth control. Immersion in a CA nanoparticle solution is an effective way of cleaning and sanitizing the orthodontic retainer as CA nanoparticles effectively removed the oral pathogens present on orthodontic retainers. 1. Introduction Oral infections caused by retainers have been a significant issue for orthodontic patients. More than 200 species of microorganisms with acid-producing capabilities can be found on the tooth surface or around the orthodontic retainer (Albanna et al., 2017). Thus, prolonged use of retainers will cause biofilms or plaque accumulation on enamel. Retainer hygiene plays a crucial role in maintaining oral health, particularly among children and adolescent orthodontic patients. The retainers are typically worn for extended period, and poor hygiene can lead to the formation of biofilms on retainers, which may subsequently increase the risk of dental caries, gingival inflammation, halitosis and periodontal complications (Chi et al., 2020). Current methods for cleaning orthodontic retainers involve mechanical brushing or chemical soaking as cleanser. However, mechanical brushing can cause damage to the surface of the thermoplastic material due to its abrasiveness (Tsolakis et al, 2019). Moreover, most cleansers are formulated with persulfate, monopersulfate, and ethylenediaminetraacetic acid (EDTA), which could trigger allergy reactions and gastric perforation (Ingram et al., 2008). The use of zinc in some orthodontic products has been reported to cause severe injuries. Besides, excessive ingestion of zinc also causes nerve damage (Choi et al., 2020). Thus, using a less toxic organic compound in orthodontic products is necessary. •••••••••••••••••••••••••••••••• ejprd.org - Published by Riset Publishing services LLC
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