Sterilizer Q & A

  • My sterilizer is losing pressure, what could be the cause of this?

    The most common causes could be your door gasket or your safety valve. Check those first.

  • Is it better to have an autoclave, chemiclave, or dry heat sterilizer?

    Most offices should have either an autoclave or chemiclave unit, because these are the only sterilizers that will sterilize handpieces. Only steam or chemical vapor sterilizers will sterilize at or below 135°C, the maximum temperature that handpieces can tolerate. Adry heat sterilizer operates at a much higher temperature, so it can't be used for handpiece. It would cause them to corrode or dull them. Dry heat units are better suited for orthodontic offices.

  • My sterilizer is not venting properly. What could the problem be?

    Many things are brand specific. For Statims, check out our Practice Tip #20 and Practice Tip #21 for troubleshooting any of your errors.

  • How often should I use a spore test on my sterilizer?

    It should be done on a weekly basis, but check the ADA regulations for your location.

  • My instruments are starting to show signs of rust! Is this caused by my sterilizer?

    A number of things can cause corrosion on your dental instruments. The first thing to check is whether or not they are properly cleaned. Debris can bake onto the instruments during the sterilization process, which can make it look as if they are rusted. To confirm if it is corrosion or staining, use a rubber eraser on the "rusted" areas to remove the discoloration. If the instrument is pitted underneath, it is actual corrosion (rust). If the instrument is smooth, it is just staining.

  • Why is distilled water required in an autoclave sterilizer?

    It is required, because non-distilled water can interfere with the operation of the autoclave. It can cause clogging and other issues.

  • What is the average life span of a sterilizer?

    As with most things, if properly maintained it will last several years and it will depend on how often you use it.

  • What can I be doing routinely to maintain my sterilizer?

    There are a quite a few things that we suggest you to do weekly, monthly, and yearly to maintain you sterilizer. Our blog has a whole Practice Tip dedicated to this (see Practice Tip #14).

  • My dental instruments come out of the autoclave looking tarnished. Is it my sterilizer?

    Test it using the eraser method: Take a pink eraser on the stains. If the tarnishing comes off, you have clean metal underneath (not pitted). It is probably just staining. Make sure your cleaning protocols are being done properly. Also, make sure you are using the correct water in your sterilizer (distilled or de-ionized water). If you have been using tap water, there could be build-up inside the sterilizer. Another thing to check is your filter(s). If they are discolored, you need to change the filter(s). Typically, the filters and door gaskets need to be replaced annually. If they needed to be replaced, run your sterilizer for a few cycles with a cleaner designed for your sterilizer and run an extra cycle using just distilled or DI water.

  • I am designing my sterilization area and need some advice on what I should do. Where should I start?

    In order to have a well-designed space for sterilization, you need to have a good work flow: contaminated items > sink > Ultrasonic > sink > non sterilized items > autoclave > sterilized items. Instruments should flow from dirty to clean, in a linear fashion. There should be physical space separating contaminated & sterilized items. Cassettes can help with organization & efficiency. We have cassettes in both stainless steel and plastic, with a wide range of sizes. Compare the sizes to your instrument set-ups & sterilizer chamber dimensions to find the best match for you. Plastic cassettes are light-weight and come in a rainbow of colors to facilitate color-coding. Stainless cassettes are extremely durable and should last for many years and make long term economic sense.

  • When replacing a door gasket, do I need to replace the door dam as well?

    For most sterilizers, both the door gasket and door dam should be replaced annually. The Midmark M9 & M11 sterilizers should have their gaskets & dams changed every six months. Consult your owner's manual for more details, although we recommend routine maintenance (Practice Tip #14). Beyond maintenance, you should only replace items that are worn. It isn't unusual for only the gasket or dam to wear.

  • My manual Tuttnauer sterilizer will randomly (not always) spill a ton of water out the door when it's unlatched after a cycle. The water is cold, so it might not have actually ran through the cycle. What is going on?

    Sporadic problems are always tricky to diagnose. Human error is certainly the most likely culprit. Check for any signs of clogs in the chamber filters (visual inspection) and condensation coil (run a wire cleaning brush through it). Check your door bellows, air valve jet, and safety valve. These are all easy to check and could be just starting to go. The air valve jet should move freely and allow some steam to escape during the cycle (but not a lot). The safety valve should, also, move freely and not stick open, but snap back closed. If you need further assistance, give our technicians a call.

  • I've noticed a few things around the office that need maintenance regularly. I have trouble with my sterilizer. What should I be doing on a regular basis?

    We've had a number of monthly practice tip newsletters dedicated to routine maintenance.Practice Tips #34 is a comprehensive list of maintenance to perform on equipment throughout the office & Practice Tip #80 includes routine maintenance, along with other simple things you can do to keep all of your equipment running well. As for your sterilizer, maintenance is discussed in Practice Tips #14

  • The mouth props come out of my autoclave melted and there are water stains on my autoclavable bags. I've set the sterilizer on the lowest setting and don't know why this keeps happening. What should I do about my sterilizer?

    It is most likely a bad temperature gauge, but first check with a lag thermometer (#RP-113) to check the accuracy of your temperature gauge. When the autoclave is running through a cycle, watch the pressure. There is a direct correlation between temperature and pressure. For example: 121° C should get you 15 psi & 135° C (normal autoclave maximum) should read 31 psi. NOTE: the safety valve on your sterilizer will crack around 35 psi, so be careful.

  • I've replaced the orange door gasket on my Midmark M3 sterilizer, but I am still getting the "low pressure" message still. What else do I need to fix?

    There are a few reasons you could still be getting this message. Make sure you have adequate water flow in and that the water line is clear. If you don't have these things, you won't be getting proper pressure. The second option is to run a cycle with the cover off and see where there might be steam leaking. The seal should be changed regularly as part of your routine maintenance (Practice Tip #14). Do you receive a corresponding error code with the low pressure warning? The code could help narrow down the possibilities of what could be wrong with your sterilizer.

  • I would love to learn how to troubleshoot and repair my own autoclave. Can people service their own equipment?

    Absolutely! We have a ton of resources just for dentists, as well as any staff member. Our monthly Practice Tips and blog give tailored troubleshooting and assistance for do-it-yourselfers all of the time. On top of those resources, we have a YouTube channel with helpful DIY videos for you to follow along with. If you don't find what you are looking for, give us a call and we can find the specific repair parts for your autoclave.

  • I purchased a new sterilizer. How should I store my old sterilizer if I need it as a backup?

    Your sterilizer should be stored dry, with no water leftover in the reservoir. The best way to do this is to use your suction to drain it.

  • How many sterilizers should I have in my office?

    A lot of dentists have more than one sterilizer in their sterilization center. It helps avoid downtime and if there is a problem with one of the autoclaves, they can have it serviced without interrupting your office flow.

  • My Midmark M11 autoclave will have a full amount of water in the chamber, but will stop during a cycle. It will say "water low." Water pours out when I open the door. What should I be fixing?

    Check your sensors. It is most likely a bad water sensor or temperature sensor causing your autoclave to act up. When they fail, it causes it to overfill. Also, make sure your sterilizer is level & your water level sensor is clean (a Scotch-Brite pad will help shine it up and free it of any build-up).

  • I perform the recommended maintenance daily, weekly, monthly, quarterly, & yearly on my sterilizer. I also send in weekly biological tests and pass. However, I've noticed grime inside the water reservoir tube. What am I not doing right?

    You aren't doing anything wrong. Even with all of the suggested maintenance and testing, you can still get deposits in the water lines. Using a narrow cleaning brush in the tubing will help you get rid of the grime. We suggest adding this step to your annual maintenance, along with replacing your filters and gaskets.

  • I have replaced the door gasket on my Midmark M9 sterilizer, but it's still leaking steam when it's gaining pressure. What is the next step?

    Your door springs might be causing you trouble as well. They should be replaced during your annual dental office maintenance routine. Make sure you are lubricating your door hinges once a month too. Try running a cycle with the cover off and the insulation removed from inside your sterilizer. There could be a leak somewhere else and you are just seeing it around the door. Other areas to check would be your bellows or safety valve. Once you assess your sterilizer with the case and insulation removed, you will be able to see the cause for the leak better.

  • I installed a new door gasket in my sterilizer, but it looks loose. Did I buy one that was too big?

    You didn't buy the wrong one. All door gaskets will look slightly larger after installation. Due to material of the gasket, they will shrink when it heats up. However, there shouldn't be large gaps after you install it. Make sure you follow the provided instructions.

  • My office doesn't have an autoclave, but a chemiclave instead. Can I use the chemiclave to sterilize my plastic sectional matrix rings?

    Check the rings' manufacturer guidelines first. Some autoclavable plastics are not safe for chemiclaves. The solution that is used will dry out and crack the plastic. Chemiclaves are ideal for metal instruments, but can be harsh on plastic instruments.

  • The small filter in my M11 sterilizer's pressure chamber was dislodged and settled on the bottom. My assistant's didn't notice when they started the cycle before they left for night. The next day, the M11 had an error message and the x-ray positioners had melted. How do I fix it?

    Those mesh filters (#TU-63) are important and should be checked weekly. Replace them annually and/or replaced at the same time as the door gaskets and dam every 6 months. Routine maintenance is discussed further in Practice Tip #14. An overheating sterilizer is the result of water issues— low or inadequate water flow can cause the sterilizer to run dry at a high temperature (as you can see by your melted plastic pieces).>

  • There is a crack in the plastic of my sterilizer's handle. Is this replaceable? Why would the plastic start to crack?

    If your sterilizer is starting to run hot, that could be caused by poor water flow. The mesh filters mentioned in the previous question (#TU-63) are often forgotten or ignored, but they are your first line of defense against water issues like yours. If that doesn't solve your issue, there are other possibilities, such as having an issue with your max register thermometer. Also, plastic in general is prone to cracking from using disinfectants. The handles and other plastic parts are replaceable.

  • How should I be placing my sterilization pouches in my autoclave- plastic side up or down?

    Ideally, if your sterilizer has a rack, then you can have the pouches on their side, all facing the same direction. If you don't have a rack, you will have to lay the pouches down and the direction of the plastic will depend on the direction of steam flow in your sterilization chamber. For a gravity steam sterilizer have the plastic side down, since steam rises and the plastic will trap the steam. For a vacuum steam sterilizer have the plastic side up, since the vacuum directs the steam downwards for ventilation.

  • The office will run of our instruments through the autoclaved unwrapped and then sort them onto specific procedure trays and then store in the cabinets. Shouldn't I be using bags for my instruments during sterilization?

    Instruments can be sterilized without a pouch, but they should be put into immediate use afterwards per CDC guidelines. By putting them on a tray after sterilization, you aren't keeping up to current infection control regulations. We suggest using the bags if you are storing your dental instruments.

  • My Midmark M11 sterilizer quit- it won't turn on, including its lights. What happened?

    It is most likely blown fuse. There are two different ones on the M11. Look at your manual to find them (they can be hard to find). Replace the fuses, but also check your breaker. Hopefully you didn't pop a circuit, since your autoclave can use quite a lot of power. Putting your autoclave on its own circuit would be smart.

  • Can I autoclave my dental burs in bur blocks or will this not sterilize them properly?

    Depending on the type of bur and the type of bur block, yes you can put them in your autoclave. Some of the metal bur blocks will react differently with the burs and can degrade them more quickly, possibly fusing the bur and the block together. Most of the metal bur blocks are made from anodized aluminum and would be fin with most burs. Our suggestion is to use dry heat, rather than an autoclave, with your carbide burs. Steam can lead to the burs being corroded or dull the bur in the process, as well as break down the adhesive on some diamonds.

  • My Tuttnauer hasn't been draining water out of the front drain properly. We tried blowing air out of the drain, but haven't been successful. What could be going on?

    Checking for a clog is the right idea. Try running a narrow cleaning brush through the line and check your chamber filters. One possibility is a bad drain valve. Check this by disconnecting the line from the drain valve and see if that helps with the flow of water. If not, replace the drain valve.

  • Both of my M11 Midmark autoclaves have a cracking plastic cover where the steam is being released. They are used every day, so what can I be doing to make sure they keep working right?

    The cracking probably means it is running too hot due to poor water flow. Checking your filters and seals. They should be practicing proper maintenance and change these. Practice Tip #14 talks about what and when to change things before they go bad. As far as the cracking plastic, don't use disinfectants to clean it. This causes cracking to occur. We also carry replacement doors and panels if this does happen.

  • Besides steam sterilization, how would cold sterilization apply in a typical dental office?

    Cold sterilization is immersing reusable dental products that are semi-critical in a liquid chemical and disinfecting it over a certain length of time. It can take a while for instruments to be considered sterile enough to be used. You would typically use this method to sterilize items that would be damaged by heat. Check back for more information. We would love to explain this further in one of our Practice Tips.

  • Should I use sterilizer bags or cassettes in my autoclave?

    There are a lot of dentists that have strong opinions on both sides of this question. Cassettes provide a higher chair turnover and are a great solution for instrument organization and storage. With cassettes there will be less handling of sterile instruments- no incidental pokes, no need for heavy duty gloves, and no time wasted sorting through items. Sterilization bags are a good product if you use minimal instruments and don't have a need for large instrument kits.

  • Occasionally my sterilization pouches are coming out of my autoclave burnt. What is happening?

    If your mesh filters are clear, it could be the solenoid valve. Your burnt pouches are a clear indicator that your autoclave is overheating, usually due to low water levels. Another reason this could be happening is human error (ie: overloading your autoclave or your pouches were touching the heating element).

  • At the end of my solenoid valve on my Statim it is leaking and the tubing isn't staying connected. What needs to be replaced?

    Take a razor blade and cut off the tubing and reattach to the fitting. If it still isn't staying connected or you notice the plastic is fractured inside the fitting, replace the push-in fitting too.

  • I am looking into a M11 sterilizer and noticed the cycle time for bagged instruments is 5 minutes at 270° F. That sounds like too short of a cycle to me. Midmark's literature recommends 10 minutes at that temperature. Are they wrong?

    You should always defer to the sterilizer's manufacture guidelines. Specifically, the M11 allows you to change the pre-programmed cycle times if you want. With a 5 minute cycle at that pressure and temperature, you will reach overkill time for sterilization, even with an instrument pouch. Most of the total cycle time is taken up with the drying process and a little of that time is also to reach peak temperature. Sterilization of the instruments doesn't take that long. The time it takes to render a dental item sterile won't change based on the brand of autoclave. The only thing that will change is heat up and dry time.

  • Is my autoclave required to use the manufacture specified HEPA filter or could I use a cheaper non-OEM filter instead?

    There are after-market air filters that are made with the same specs as the OEM, if you are looking to save money. We don't recommend using a filter with different specs, since the results aren't known and could affect your sterilizer to underperform.

  • I replace my Tuttnauer door gaskets every 4-6 months. How can I extend the longevity of them?

    Usually, you should replace your gaskets every 6 months, but Tuttnauer's should be good for at least a year (ours are under warranty for one year). One way to extend their life is to periodically lubricate the gasket with liquid soap once a week or even monthly. When installing, make sure you are doing it properly. See Practice Tip #93 for more detail on door gaskets and their installation.