“Dentistry is one of the most carbon-intensive sectors in the world”

In dentistry, an enormous amount of single-use plastic is consumed. Dentists see at least fifteen patients a day, and for each one—even just for an annual check-up—around 200 grams of plastic ends up in the bin. That adds up to roughly three kilograms of waste per day from gloves, face masks, and dental materials. Even more is used during treatments and procedures. According to figures from the National Institute for Health and Disability Insurance, three million composite fillings were placed last year. These fillings are made from synthetic resin, binding agents and inorganic fillers like quartz or glass. The result is thousands of tonnes of plastic waste from dental practices entering the waste stream. The major issue is that this waste isn’t recycled. It’s all classified as medical waste and must be incinerated separately. That process consumes a significant amount of energy. Special filters are used to capture the harmful gases, but they’re extremely costly, and cleaning them is far from sustainable.

There is no waste sorting in dental practices because the law doesn’t allow it. A missed opportunity, according to Mohammed. “Dentists need to become aware of the amount of waste they produce. And to do that, it’s important to understand where that waste is coming from. Take a simple check-up, for example: the patient wears a bib made of two parts—ten grams of paper at the front, ten grams of plastic at the back. The soft suction tips used to remove saliva weigh around 30 grams and contain a small metal part inside. When placing a filling, adhesive material is used to bond it to the tooth. This is applied using a plastic micro-applicator—two are used per filling, weighing just 1 gram in total. It doesn’t seem like much. But when you consider there are 6,700 dentists in Belgium, 310,000 in Europe, and 1.2 million worldwide, that adds up to 1.5 million kilos per year of this tiny instrument alone ending up in medical waste.

All of it is incinerated, because it’s considered contaminated. But is that really necessary? Why can’t dentists sort some of this waste themselves in the practice? If I wash my hands and use a tissue, it’s not actually contaminated and could go in with general waste. The same goes for a face mask used during a routine check-up, where there’s no trace of blood. When new materials are delivered and unwrapped in the surgery, that plastic has to go into medical waste too—even though it would be perfectly suitable for standard PMD recycling. We urgently need policymakers—like the Ministry of Health and RIZIV—to provide proper guidance on this.”

“Dentistry is one of the most CO₂-intensive sectors in the world. That’s why we need a new generation of materials and instruments with a lower environmental impact. As part of my research, I worked with several industrial partners to develop prototypes of micro-applicators made from CO₂-neutral wood or bamboo, as well as other models made from PLA (polylactic acid), a biodegradable plastic with a much smaller environmental footprint. If you were to incinerate PLA as medical waste, it would require thirteen times less energy.

All these designs have been patented under the name DentPlanet. We also developed paper fluoride trays. Until now, these have been made from foam rubber and are placed in children’s mouths for fifteen minutes by dentists to help prevent cavities. Both the micro-applicators and the fluoride trays have now received a CE label, confirming that they meet European standards for safety, health, and environmental protection.”

Anyone who thinks things are much better at home is sorely mistaken. “A family with two young children uses around 1.5 kilos of oral care products each year. In Belgium alone, that adds up to nearly one million kilos of waste—just from brushing our teeth. That’s staggering, isn’t it? Last year, I submitted a proposal for the first plantable toothbrush. After use, you simply plant the wooden brush in the ground. It has a small cavity containing seeds, which come with it. Not only does this reduce the environmental impact, but it also gives something back to nature—literally letting a new plant grow. That’s what I call ecological gain.”

Eco-friendly products for dentists, like organic goods in a supermarket, are more expensive than their non-sustainable counterparts. “That’s due to higher production costs. Dentists working under the national health insurance scheme aren’t allowed to pass those additional costs on to the patient. So I have to rely on the dentist’s personal goodwill and environmental awareness to choose the more sustainable option. From our research, we found that awareness of eco-friendly dental materials is virtually non-existent. That’s the challenge I’m up against.”

Mohammed runs accredited training courses for dentists on reducing dental waste.