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#Industry News
Metallic dust, crystalline silica, resin dust and chemical vapours: why air quality is crucial in dental prosthetics laboratories
A key issue for preventing occupational diseases among dental technicians
In dental prosthetic laboratories, air quality is often an overlooked issue, despite the fact that professionals are exposed daily to various pollutants. The processes involved in the manufacturing and finishing of dental prostheses release chemical substances and fine particles that can be hazardous to health. Each activity in the lab is prone to releasing specific pollutants, depending on the materials handled (resins, metals, ceramics) and the tools used (burs, polishing machines, furnaces). Without adequate air quality control, dental laboratories can become environments where serious occupational diseases may develop. In this article, we will highlight the main health risks faced by dental technicians and the importance of preventing these dangers.
The dangers of air quality in dental laboratories
Dental technicians are exposed to various pollutants generated by different products and processes used in their work. The most common pollutants include:
• Fine particles: These are generated during polishing, grinding, or cutting prostheses and can penetrate deeply into the respiratory system, causing lung diseases.
• Chemical vapours: Substances such as methyl methacrylate (MMA) found in acrylic resins can cause eye, nose, and throat irritation and, with prolonged exposure, can lead to respiratory issues and more serious illnesses.
• Metal dust: Used in the production of crowns and bridges, this dust can contain cobalt, nickel, or chromium, all of which are known allergens and toxic substances.
According to the French National Research and Safety Institute (INRS), "inhalation of these dusts or vapours can lead to occupational diseases such as asthma, respiratory allergies, silicosis, or chronic lung conditions."
Types of pollutants depending on laboratory activities
Each stage in the manufacturing of a dental prosthesis exposes technicians to different pollutants generated by the products and work processes. Below is an overview of the main pollutants linked to specific activities in dental laboratories:
1. Preparation and polymerisation of Acrylic Resins
o Main pollutants: Methyl methacrylate (MMA), formaldehyde, acetone, toluene.
o Associated risks: These volatile organic compounds (VOCs) are released during the manipulation and curing of resins used in the creation of removable prostheses and inlay cores. Methyl methacrylate, one of the most commonly used substances, is known for its irritant effects on the eyes, skin, and respiratory system. Long-term exposure can also cause allergic reactions and chronic respiratory diseases.
2. Grinding and polishing of prostheses
o Main pollutants: Fine and ultrafine particles (PM10, PM2.5), crystalline silica, cobalt, nickel, chromium.
o Associated risks: Grinding, cutting, or polishing prosthetic parts generates large quantities of fine and ultrafine dust, especially when working with metallic alloys. Crystalline silica, which is found in some abrasive materials, is particularly dangerous. Inhaling these dusts can lead to severe respiratory diseases such as silicosis, an incurable lung disease, or even respiratory cancers. Additionally, cobalt, nickel, and chromium are metals commonly used in dental alloys, classified as carcinogenic and known to cause lung diseases and allergic skin reactions.
3. Firing and treatment of dental ceramics
o Main pollutants: Zirconium oxide, aluminium oxide, carbon monoxide (CO), nitrogen oxides (NOx).
o Associated risks: When firing crowns and bridges made from ceramics, fumes and fine particles are released into the air. Zirconium oxide, used in the creation of ceramic prostheses, generates fine dust during polishing and grinding. These particles can irritate the respiratory system and cause chronic lung conditions. Moreover, high-temperature firing in dental furnaces releases carbon monoxide and nitrogen oxides, which are harmful to both the cardiovascular and respiratory systems.
4. Handling metal alloys for crowns and bridges
o Main Pollutants: Metal dust, lead, cadmium, mercury.
o Associated Risks: During the casting and grinding of metal alloys, technicians are exposed to fine metal dust often containing lead, cadmium, or mercury. These substances are highly toxic and can cause neurological disorders, kidney disease, and cancer. Chronic exposure to lead, for example, has been linked to nervous system disorders and can affect cognitive development.
5. Cleaning and disinfection of prostheses and instruments
o Main Pollutants: Disinfectants containing glutaraldehyde, sodium hypochlorite, hydrogen peroxide.
o Associated Risks: The use of these disinfectants can release irritating vapours that cause acute and chronic respiratory conditions such as occupational asthma. Glutaraldehyde, in particular, is recognised as highly irritant and sensitising. Improper handling without adequate protection can lead to severe allergic reactions and long-term respiratory issues.
Occupational diseases linked to air quality
Poor air quality in dental laboratories is a major cause of occupational diseases. According to INRS statistics, respiratory diseases represent a significant proportion of reported conditions in this sector. Some of the most common pathologies include:
• Chronic respiratory diseases: Prolonged inhalation of fine, metallic, or silica dust promotes the development of respiratory conditions such as chronic bronchitis, chronic obstructive pulmonary disease (COPD), and even cancers of the respiratory tract. INRS reports that bronchopulmonary diseases linked to the inhalation of mineral dust (such as silica) are particularly common among workers in dental laboratories. In France, COPD is the third leading cause of death, and its links to occupational exposures are increasingly well-documented.
• Allergies and occupational asthma: Chemical compounds in resins, metals, and disinfectants can cause severe allergic reactions. Occupational asthma, increasingly diagnosed in this sector, is often triggered by repeated exposure to VOCs or irritating dusts.
• Occupational dermatoses: Direct contact or inhalation of chemicals in acrylic resins can cause contact dermatitis or chronic eczema, which can be particularly troublesome for technicians.
• Occupational cancers: Certain substances found in dental laboratories, such as nickel and chromium, are recognised as carcinogenic by the International Agency for Research on Cancer (IARC). Prolonged exposure to these metals increases the risk of cancer in the respiratory tract.
Solutions to improve air quality
Given the variety of pollutants in dental prosthetic laboratories, it is essential to adopt a comprehensive approach to risk prevention. Below are the main preventive measures to consider:
1. Adequate Ventilation Systems: Installing controlled mechanical ventilation (CMV) systems helps regularly refresh the air in workspaces and reduces the concentration of pollutants.
2. Localised Ventilation Systems: Installing dust extractors close to emission sources (such as polishing or grinding stations) captures the particles at the source before they spread throughout the air.
3. Air Filtration Systems: Air purifiers equipped with medical-grade HEPA filters, such as the EOLIS Air Manager, are particularly effective in capturing fine particles (down to 0.3 micron), metal dust, crystalline silica, and other airborne contaminants right at the source. The use of activated carbon filters can effectively remove volatile organic compounds (VOCs) such as methyl methacrylate, thus reducing irritation and allergic reactions.
4. Chemical Emission Control: An air quality monitoring system allows real-time tracking of pollution levels in the laboratory and verifies the effectiveness of air purifiers.
5. Personal Protective Equipment (PPE): In addition to air filtration systems, wearing PPE (FFP2 or FFP3 respiratory masks and protective eyewear) is essential to limit exposure to harmful particles.
EOLIS Air Manager: The air purification solution for dental technicians
NatéoSanté, a French designer and manufacturer, offers air purification solutions specifically tailored to the health needs of dental technicians. Our professional air purifiers, such as the EOLIS Air Manager range, are designed to capture and eliminate pollutants present in dental laboratories, ensuring a safe and healthy work environment:
• Fine particle filtration: HEPA filters (High Efficiency for Airborne Particles) capture up to 99.97% of fine particles (PM10, PM2.5), including silica dust, heavy metals, and dust from resins and ceramics.
• VOC and toxic vapour neutralisation : The high-density activated carbon filter is ideal for absorbing volatile organic compounds (such as methyl methacrylate), as well as toxic gases like carbon monoxide.
• Medical-grade HEPA filtration: Captures up to 99.97% of fine particles (PM10, PM2.5), including metal dust and crystalline silica, reducing the risks of chronic respiratory diseases.
• Advanced UV-C Technology: Built-in germicidal UV-C lamps destroy pathogens such as viruses and bacteria, ensuring an even healthier environment.
• Effective Management of Pollution Peaks: With suitable filtration systems, PM and VOC sensors that measure air pollution in real time, the EOLIS Air Manager offers tailored purification settings depending on laboratory needs.
Conclusion
Air quality in dental prosthetic laboratories is a critical issue that must not be overlooked. Exposure to airborne pollutants can lead to chronic respiratory diseases, allergic reactions, and long-term health problems for technicians. By using ventilation, filtration, and protective measures, it is possible to minimise the risks associated with poor air quality. The EOLIS Air Manager provides a state-of-the-art solution for improving air quality in these environments, ensuring the health and safety of dental technicians.
Contact a NatéoSanté expert and get a free audit: https://www.nateosante.com/en/contact-us/