Restorative dental care has seen a substantial shift in recent years, as professionals look to employ resin-based composite (RBC) restorations in their care more often. This could be because of the advancement of the aesthetic potential of such solutions, as well as the push to reduce amalgam use – dental professionals across the EU will have their hand forced with the amalgam ban beginning from January 1, 2025, and practitioners in the UK will likely see disruption and higher costs because of the resultant pressures on supply chains.
Many clinicians currently use RBC solutions and will likely use them more frequently in the future, which requires appropriate management of any waste created. It’s important to delve into the current understanding of the health and environmental risks of RBC use, and waste. With this knowledge, best practice workflows when discarding the material in daily care are possible.
Risk management
Resin-based composite is a preferred restorative material due to its aesthetic appearance and ability to blend in with the existing dentition. In addition, it can withstand high compressive forces – necessary to bear occlusal contacts – leading to long-lasting results. As such, the material often replaces amalgam as a go-to for dental fillings.
Amalgam has been criticised as an unviable restorative material for the future of dental care, partly due to the impact of mercury on the environment. If improperly wasted, the resource could contaminate water sources, harm aquatic organisms and work its way into the food chain. If consumed in large quantities, individuals may experience reproductive problems, and liver and kidney damage.
There are issues with the alternative. RBC breaks down into microparticles when shaped, finished and polished. These microparticles can reach water sources if discarded improperly, acting as direct pollutants that can also attract and bind to biotoxins known as persistent organic pollutants (POPs). It is thought that POPs bonded to microplastics can enter the food chain through bio-accumulation, and a variety of aquatic animals have been seen to ingest microplastics. The issue of microparticle production is only exacerbated with the increased use of highly polymerised RBC for the creation of crowns, inlays and onlays through reductive CAD/CAM milling, which creates large volumes of microparticle powder.
It is important to consider the general breakdown of RBC restorations and materials in landfills, in greater volumes than ever. This occurs through the process of elution, where monomers within the RBC structure are released into a solution – typically water in landfills and the environment. The chemical durability of the composite material is then compromised, creating risks for environmental pollution.
The monomers that are commonly released through elution include bisephenol A-glycidyl methacrylate (BisGMA), urethane-dimethacrylate (UDMA) monomers and, most prominently, triethylene glycol dimethacrylate (TEGDMA). Previous studies have recognised that TEGDMA has a cytotoxic effect and can affect markers of oxidative stress, making it a threat to living beings that it comes into contact with in the environment.
Conscious waste management
Unlike amalgam waste, RBC is not mentioned in Health Technical Memorandum 07-01 (HTM 07-01). However, RBC is generally designated as municipal solid waste, as it does not present the active infectious hazards of many other medical items, which may otherwise be placed in yellow or orange waste streams. This creates some issues; the typical disposal methods of municipal waste include recycling, which is preferred, or discarding the items in landfills. Here, the aforementioned risks of environmental contamination may arise.
A third option, energy from waste production, may be suitable. Whilst this process, which typically requires the combustion of waste items, produces carbon content, it is still preferable to landfills where carbon release is inevitable. Energy from waste plants can create excess energy, besides the quantity needed to run, which can support the push to reduce fossil fuel use. Resin-based composite disposed of by this method has little chance of microparticles and eluted monomers reaching key areas of the local environment.
Dental practices can ensure their Resin-based composite is managed safely and securely through being directed towards energy production from waste processing facilities or recycling. To do this, they should work with a specialist waste management service such as Initial Medical. With decades of experience in healthcare and dentistry, Initial Medical can help you manage your municipal waste workflows safely, and with simple and organised waste segregation. The team is on hand to provide advice and insight on how to optimise your waste workflows and ensure your practice better protects the environment.
Resin-based composite creates some risk to the environment if improperly managed in the waste workflow. Clinicians should avoid landfills where possible for this waste material, including any contaminated packaging, and work to protect the environment.
For more information visit https://www.initial.co.uk/medical/