The Biological Effects of 3D Resins Used in Orthodontics: A Systematic Review

Abstract

Three-dimensional (3D) resin medical-dental devices have been increasingly used in recent years after the emergence of digital technologies. In Orthodontics, therapies with aligners have gained popularity, mainly due to the aggressive promotion policies developed by the industry. However, their systemic effects are largely unknown, with few studies evaluating the systemic toxicity of these materials. The release of bisphenol A and other residual monomers have cytotoxic, genotoxic, and estrogenic effects. This systematic review aims to analyze the release of toxic substances from 3D resins used in Orthodontics and their toxic systemic effects systematically. The PICO question asked was, “Does the use of 3D resins in orthodontic devices induce cytotoxic effects or changes in estrogen levels?”. The search was carried out in several databases and according to PRISMA guidelines. In vitro, in vivo, and clinical studies were included. The in vitro studies’ risk of bias was assessed using the guidelines for the reporting of pre-clinical studies on dental materials by Faggion Jr. For the in vivo studies, the SYRCLE risk of bias tool was used, and for the clinical studies, the Cochrane tool. A total of 400 articles retrieved from the databases were initially scrutinized. Fourteen articles were included for qualitative analysis. The risk of bias was considered medium to high. Cytotoxic effects or estrogen levels cannot be confirmed based on the limited preliminary evidence given by in vitro studies. Evidence of the release of bisphenol A and other monomers from 3D resin devices, either in vitro or clinical studies, remains ambiguous. The few robust results in the current literature demonstrate the absolute need for further studies, especially given the possible implications for the young patient’s fertility, which constitutes one of the largest groups of patients using these orthodontic devices.

Direct 3D-Printed Orthodontic Retainers. A Systematic Review

“…A systematic review investigating the biological effects of 3D-printed resins used in orthodontics concludes that 3D-printed aligners exhibit higher levels of cytotoxicity and genotoxicity than thermoplastic resins, especially if they have not been subjected to a final surface treatment. This prompts the clinician to act with caution, especially when treating young children and growing patients in order to protect them from fertility issues [ 81 ].…”

Advances in orthodontic clear aligner materials

“…A systematic review of the biological effects of 3D resins used in clear aligners or retainers also reveals that the evidence of the release of bisphenol A and other monomers, either in vitro or clinical studies, remains ambiguous due to few robust results in the current literature. There is an absolute need for further studies in these domains, especially given the possible implications for the fertility of young patients [ 112 ].…”

Special Issue “Recent Advances in Biomaterials and Dental Disease” Part I

“…Harouny et al demonstrated that the use of phosphoric acid on the lithium disilicate surface provide efficient cleaning [34]. Therefore, the main aim of studies in the dental restoration field is to ameliorate the mechanical properties, bond strength, and durability of direct and indirect restoration approaches, as well as to improve the techniques used to bond brackets to teeth with different restorative materials in orthodontic treatments [35,36].…”