Waste Management for Dental Offices


The quantity of medical waste at dental offices is more-or-less proportional to the number of patients seen. Most dental office waste is not regulated and does not differ from waste from any other office of comparable size: paper, plastic, etc. that has not been in contact with bodily fluids and does not contain hazardous material. This waste, which professionals call Municipal Solid Waste, can be collected, stored, and shipped off site just like the waste at an accounting firm or advertising agency. If your facility is in an office park, it probably has a central waste collection system and most of the waste you generate can go into it,

Two types of waste deserve special attention at dentists offices:

Hazardous waste (and this is in small quantities)
Biological waste (which includes infectious waste and pathological waste)

Although radiation is used at dental offices to produce images, the x-rays are generated by an electromagnetic process, not by permanently radioactive material. Radioactive waste is not produced by x-ray equipment.

Tooth Fillings and Hazardous waste

Look at the definition of hazardous waste to see if your facility generates it. The iconic hazardous material used by dentists is mercury amalgam (an alloy of mercury). The filling material was a mix of mercury, copper, silver, and tin. This type of filling material was used on tooth cavities for over a century and still is used. However, the trend has been to move away from the old filling material because mercury is bad for people. The concern is that mercury leaks from the fillings over the years and ends up in the person’s tissues. The federal government calls mercury a neurotoxin.

While the trend has been away from mercury fillings and toward polymer resin composites (the polymerization happens after a liquid has been inserted into the cavity, and is initiated by light.) Whether this is preferable of the old-style mercury filling is desirable for long-term is a matter of debate.

Whether from amalgams for new fillings or in old teeth removed from patients’ mouths, dentists offices generate mercury-containing waste. While they have often in the past flushed these wastes down the drain into the municipal sewage system, they cannot get away with that anymore, at least in the US. In 2017 the EPA set new rules on drain flushing. The dental facilities are now supposed to install an amalgam separator in their drain system. The idea is that this will collect the mercury-containing material for removal and handling as hazardous waste. https://www.epa.gov/eg/dental-effluent-guidelines

Companies that serve dental practice can install these separators or refer you to someone who can do so.

Infectious waste

While the quantity of infectious waste generated at dentists offices is relatively small compared to hospitals, it is real and must be managed. Any time blood is involved, you have waste that should be disposed of as infectious waste. Gauze, paper product, cloth, and syringes that come into contact with blood should be placed into a container (or bag) marked with a biohazard symbol. Curiously, extracted teeth are not included, but most dental offices probably put teeth in those bags, too.

When in doubt, apply the precautionary principle and classify the waste as dangerous.

Saliva-soaked objects are not subject to the same scrutiny, unless you have reason to believe the patient has a contagious disease.

Hygienists and dentists routinely use personal protective equipment when inspecting and treating patients. They should remember to employ gloves, masks, and protective eyewear when removing amalgam waste from the separator if there is not a service company that does so. Any waste removed should be put in a sturdy container labeled hazardous waste and removed off-site within a week.

Sharps

The medical waste world worries a lot about “sharps”. Common sharps found in dental offices include needles, syringes, lancets, and instruments used to clean teeth. If it looks like someone could cut their skin on it, it is a sharp and should not be put in the trash with municipal solid waste.

Nor should they be put in bags with infectious waste. In healthcare facilities, OSHA says this about reusable sharps: “Reusable sharps must be placed in containers which are puncture-resistant, leakproof on the sides and bottom, and properly labeled or color-coded until they are reprocessed.”

Cardboard, plastic, or metal containers are acceptable for sharps so long as they meet the criteria and cannot be easily punctured. However, we advise businesses that produce sharps waste to buy a sharps container from a medical supply company.

X-ray Image Waste

Modern dental offices employ digital x-ray systems, and often no hard copy of the image is produced - the dentist looks at the teeth on a computer screen. However, when old-fashioned photography is employed, possibly hazardous wastes can be generated. Developer is a glutaraldehyde solution. Acetic acid (which isn’t particularly hazardous) is used in the stop bath. The fixer solution contains silver (a heavy metal) and also hydroquinone and about 15 percent potassium hydroxide. Waste from photo labs can be managed without getting into RCRA hazardous waste territory, and the providers of the chemicals can advise what you should to with the waste. Unused film is also a source of hazardous waste, as it contains the heavy metal silver as are the lead shields in film packets.

Just remember: just because a home photography enthusiast could get away with flushing those chemicals down the drain doesn’t necessarily mean your dentist office can do so.

Being a responsible waste management office

Now you might be tempted to throw some of that stuff into the dumpster out back - the same place office waste paper goes. DON’T DO IT. You’re running a big risk. Waste management companies are expensive, but cutting corners by cheating this way can easily come back to bite you.

It is worth typing up a waste management plan. The authorities probably do not require one, but having one will help show you are responsible if there is ever an incident. The plan need only be a few pages long. You need to form a relationship with medical waste companies that will take away your sharps and infectious waste bags.