Functional Surface Coatings on Orthodontic Appliances: Reviews of Friction Reduction, Antibacterial Properties, and Corrosion Resistance

Abstract

Surface coating technology is an important way to improve the properties of orthodontic appliances, allowing for reduced friction, antibacterial properties, and enhanced corrosion resistance. It improves treatment efficiency, reduces side effects, and increases the safety and durability of orthodontic appliances. Existing functional coatings are prepared with suitable additional layers on the surface of the substrate to achieve the abovementioned modifications, and commonly used materials mainly include metal and metallic compound materials, carbon-based materials, polymers, and bioactive materials. In addition to single-use materials, metal-metal or metal-nonmetal materials can be combined. Methods of coating preparation include, but are not limited to, physical vapor deposition (PVD), chemical deposition, sol-gel dip coating, etc., with a variety of different conditions for preparing the coatings. In the reviewed studies, a wide variety of surface coatings were found to be effective. However, the present coating materials have not yet achieved a perfect combination of these three functions, and their safety and durability need further verification. This paper reviews and summarizes the effectiveness, advantages and disadvantages, and clinical perspectives of different coating materials for orthodontic appliances in terms of friction reduction, antibacterial properties, and enhanced corrosion resistance, and discusses more possibilities for follow-up studies as well as for clinical applications in detail.

Graphene-Based Coatings for Surface Modification and Their Applications in Fixed Orthodontics: A Scoping Review

“…[8]. Orthodontic archwires are impacted by a variety of factors in the oral cavity environment, such as saliva flow, ingested liquids and food, temperature changes, tooth brushing, masticatory forces, and archwires sliding along the brackets [10]. As a consequence, plaque/biofilm accumulation, archwire/bracket friction or biocorrosion processes, and other inconveniences (e.g., the release of metal ions, which can act as allergens) may take place.…”

“…In order to improve treatment effectiveness, decrease anchorage consumption, decrease the occurrence of caries and periodontal disease, as well as enhance the safety and longevity of orthodontic attachments, it is imperative to diminish the level of friction between the archwire and brackets. Additionally, it is crucial to enhance the antibacterial characteristics of orthodontic appliances and augment their resistance to corrosion and wear through the application of surface coatings [10]. This can be implemented by creating a suitable additional layer on the surface of the metallic orthodontic components, brackets, and archwires and using various coatings on them to change the surface morphology, mechanical properties, and antibacterial properties [11].…”

“…Surface coating technology makes use of a variety of metals, polymers, and composite materials. This is currently a significant method for enhancing the effectiveness of fixed orthodontic appliances, enabling therapeutic advantages and benefits like better corrosion resistance, friction reduction, and antibacterial effects [10,12].…”

Titanium nitride (TiN) as a promising alternative to plasmonic metals: a comprehensive review of synthesis and applications

“…This antibacterial characteristic is especially valuable for implants such as cardiovascular devices, where infections pose serious risks to patient health. 238,239 Integrating TiN into biomedical implants represents a significant advancement in the field. By leveraging TiN's unique properties, medical devices can provide safer, more reliable, and longer-lasting patient solutions.…”

A Facile Surface Modification Scheme for Medical-Grade Titanium and Polypropylene Using a Novel Mussel-Inspired Biomimetic Polymer with Cationic Quaternary Ammonium Functionalities for Antibacterial Application

“…Nevertheless, there were various endeavors to improve the biological interactions between the tissue and these two artificial synthetic materials. Improving the antimicrobial capability also attracted a vast amount of research interest including the use of functional deposits or surface functionalization of the titanium or polypropylene [ 17 , 18 , 19 , 20 , 21 , 22 ] with different surface modification techniques.…”