# Environmental Impact of Orthodontics: A Literature Review of Traditional Multibracket Appliances and Clear Aligners

## TL;DR

This paper compares the environmental impact of traditional orthodontic appliances and clear aligners, finding that traditional appliances are more sustainable due to better recyclability.

## Contribution

The study provides a comparative analysis of the environmental footprints of traditional multibracket appliances and clear aligners in orthodontics.

## Key findings

- Traditional multibracket appliances use stainless steel and alumina, which are more recyclable than the thermoplastic polymers used in clear aligners.
- Clear aligners generate more nonrecyclable plastic waste and require more energy in production.
- Clinical management factors like visit frequency also influence the environmental impact of orthodontic treatments.

## Abstract

Climate change has led to a growing interest in environmental sustainability in the healthcare sector, including orthodontics. This review aims to analyze and compare the environmental footprint of traditional multibracket appliances (TMAs) and clear aligners (CAs), focusing on five aspects: manufacturing process, pollution from raw materials, clinical management, and recycling potential.

A comprehensive literature search was conducted on different databases: PubMed, Scopus, Web of Science, Google Scholar, and ScienceDirect. In addition, a manual and gray literature search was performed. Included studies were reviews, systematic reviews, epidemiological studies, or life cycle assessment (LCA) addressing environmental aspects of orthodontic materials and treatments. The articles included in the review were then divided into the following categories: manufacturing processes, environmental impact of production, clinical management, and generation of waste with recycling potential.

A total of 34 studies published between 2003 and 2004, along with academic books and technical/informational sources, were analyzed. The production of TMA materials relies mainly on stainless steel (SS) and alumina, while CA uses thermoplastic polymers such as polyethylene terephthalate (PET), glycol‐modified PET (PET‐G), and polyurethane (PU). Although SS production generates higher CO2 emissions, it offers better recyclability. In contrast, CA materials production requires more energy and generates a larger amount of nonrecyclable plastic waste. The environmental impact is also influenced by the clinical management of these therapies, such as the time and frequency of visits.

Both systems contribute to environmental pollution. TMA appears more sustainable due to its recyclability and reduced waste generation. Future research should focus on improving recyclable polymers, sustainable production methods, and optimized clinical workflows.