D.A.S.H Dental Aerosol Safety Hood
Why did you design the Dental Aerosol Safety Hood (D.A.S.H.)?
I started the design when the COVID-19 safety discussions in orthodontics started to be about how we could eliminate aerosols in our practice. I realized that I didn’t want to eliminate using a handpiece, or air/water syringe. That would decrease patient comfort and decrease the quality of my bonds. However, I wanted to feel safe in my office while still using a handpiece and air/water syringe. I also didn’t want to wear a face shield all day. To me, that splatter and aerosol should be stopped before it even gets a chance to get to your PPE. The PPE should be the last line of defense not the first.
What was your inspiration for the design?
My wife works in a clinical laboratory and much of their work with potentially infectious substances is under a negative pressure hood. I started to think, why can’t we do something like that with an isolated negative pressure area around the patient. This has been attempted before. However, many of the other designs use cellophane that makes the patient feel uncomfortable and is hard for the operator to see and work through. So something that would work had to be solid Plexiglas with a 365 degree clear vision. That way patients would feel comfortable.
A friend of mine is a general dentist and I knew that the ability to not get reflection in your eyes and splatter on the field of view was important. The glass between the operator and the patient had to be angled so that the operatory light and loupes would not reflect back into your eyes. There had to be enough clearance so that the inside surface would not fill with splatter. This would also give the patient enough space so that they would not feel closed in. Lastly, the bottom had to tilt up for easy entry and exist by the patient and also for easy cleaning.
What are patient’s reactions to being treated under the D.A.S.H.?
To this point we have not had a single patient complain or say that they feel uncomfortable. If anything, I think that they are far more comfortable knowing that this technology is protecting them.
What to patients report about the noise from the vacuum?
This was probably the biggest shock to me. Many patients say that they like the noise. It makes them hear the sound of the handpiece less. We really do forget how much patients don’t like that sound.
Does the D.A.S.H. come with its own vacuum?
No that is purchased separately.
What vacuum does Dr. Kazmierski use and why?
After much research, my strongly preferred vacuum for my own use is the Festool CT 15 dust extractor. This extractor has been tested in accordance with EPA RRP. This HEPA filtered vacuum is tested and certified in accordance with IEST RP-CC-001, to filter and exhaust air particles to 0.3 microns with at least 99.97 % efficiency with no bypass leakage. It has a maximum airflow of 130 cfm. Its maximum vacuum (the power of the vacuum to overcome resistance) is 96 inches. The sound level is 70 dB.
If you compare these ratings with extra-oral dental suctions you will find that he Festool CT-15 meets or exceeds the performance numbers for almost every one of them. Also, and perhaps most importantly, I have not yet found a single extra-oral dental suction with the HEPA certifications and certification for no bypass leakage that Festool CT-15 has. Many of the popular (and expensive) extra-oral dental suctions have certifications given in China.
There are other vacuums in the dust extractor industry that will meet the same standard as the Festool CT-15. However, while the selling price of the Festool CT 15 is currently $349, most others are double that price or more.
Are other professional HEPA certified Vacuums / Dust Collectors able to be used with the D.A.S.H?
Yes! There are many others. In the Festool line with HEPA certified filtration is CT MINI I HEPA, CT MIDI I HEPA, CT 26 HEPA, CT 36 HEPA, and CT 48 HEPA. The Makita XTRACT VAC™ model VC4710 is also an option when the optional HEPA certified filtration set is used with it. When you investigate the performance and price of these units, you will understand why Dr. Kazmierski is using the Festool CT 15.
What vacuum needs to be used with D.A.S.H.?
Any vacuum can be used as long as it meets the minimum requirements that D.A.S.H. has been tested with. First and foremost the vacuum should either vent to the outside or it should be HEPA certified and also certified to have no bypass leakage. It is not enough merely to have a HEPA filter on the vacuum. Many inexpensive wet/dry vacuums and the dental extra oral “dental” suction units currently being sold do not meet this standard. In addition to being HEPA certified, the airflow should be at least 130 CFM and the static water lift should be at least 96".
Is the high speed evacuator on my dental delivery unit sufficient?
No. It is not even close to the suction needed to remove aerosols with or without D.A.S.H. Please see the part of our video where we test this type of evacuator with a fogger to see why this not enough. Interestingly, we found that adding a funnel to the end of a dental side unit suction actually decreased the ability to remove aerosol. The funnels look great. However, in our strong opinion, they perform poorly. The dental high speed evacuator on your delivery unit can and should be used as an adjunct evacuator. This is a belt and suspenders approach to aerosol control.
How do patients enter and exit the chair:
The hood tilts back and the D.A.S.H. pulls back away from the chair for entry and exit.
What if the patient is larger adult or a smaller child?
The D.A.S.H. also adjusts in height. However, once you get it set up for you, your chair, and your favorite sitting position, you won’t have to adjust the height very often. I try to keep the bottom of DASH about 1” to 2” above the patients mouth during aerosol generating procedures.
How do you use the D.A.S.H. in your own office?
Four of the five chairs in our treatment area are equipped with D.A.S.H. and Festool CT-15 vacuums. All patients treated in these chairs are treated under DASH. The vacuum is not used unless an aerosol generating procedure is actually being performed. This makes it very convenient if the patient needs an unplanned bonding or a procedure which we did not anticipate would require aerosol generation.
The Vacuum is turned on and off with a remote button as needed (see below as to how to set up the remote on/off). We leave one chair open without DASH for procedures such as scanning and for quick non-aerosol generating procedures such as retainer checks. We do clean DASH between every patient seen under it (see instructions below).
Should I stop using my current protections such as high speed suction and other PPE.
Absolutely not. Continue using the protections that you currently are, such as the use of the high speed evacuator on your delivery system during 4 handed dentistry. Think of the D.A.S.H. is a spectacular addition to greatly increase your defensive line and your feeling of safety while performing aerosol generating procedures. I personally do not wear a face shield while using DASH. This is because of the Plexiglas that DASH already places between me and the patient.
What additional products will I want to purchase for the D.A.S.H.?
Dr. Kaz uses the Festool CT 15 for his vacuum. It can be ordered online at https://www.festoolusa.com/products/dust-extraction/mobile-dust-extractors/574831---ct-15-hepa-usa
As more D.A.S.H units are sold, there is a risk of the Festool CT 15 selling out. It is a brand new model. So direct purchase at a Festool dealer may be thought if you want to make sure that you get one.
To allow the Festool CT 15 to be turned on and off remotely and wirelessly we recommend the following purchases from Amazon:
A remote on/off switch that we use:
You will want to know that the Festool 15 turns on remotely only when the remote outlet above is plugged into the outlet on the CT 15 and not into the wall outlet it is plugged into. That is because it is designed to turn on automatically when a power tool, connected to the outlet on the unit is turned on.
As a result we plug the following into the above outlet switch:
The following is placed into the above sockets to create the actual current draw needed for the Festool CT-15 to be turned on remotely:
You may find other means of providing the current draw. However, this has worked for us and is inexpensive. The more expensive units bypass this need and have Bluetooth. However, they are double the price.
To Clean the D.A.S.H. Plexiglas hood, alcohol, ammonia, and similar solvents should not be used. Instead, we use a diluted bleach solution as per the protocol recommended by the University of Michigan.
Their information can be found at: https://www.canr.msu.edu/news/covid-19-disinfecting-with-bleach . For a 7.5% bleach Clorox bottle, we dilute 9ml of this with 480 ml of water. Please note that the solution is only good for 24 hours. A new batch will be needed at the beginning of every work day. Also, the University of Michigan’s recommended 5 minutes contact time is more conservative than the 1 minute currently recommended by the CDC.
Typically we will spray the D.A.S.H. as soon as the patient leaves. Then we clean the chair, remove the instruments, and then clean the delivery unit. Finally, we dry the dash off with a microfiber window cloth.
Suggested disinfecting supplies for cleaning the Plexiglass on D.A.S.H. include:
For wiping the Plexiglass after the recommended kill time: https://www.amazon.com/gp/product/B079HLKVJR/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
Spray bottles for the diluted bleach solution:
Graduated cylinders for measuring the diluted water and bleach solution: https://www.amazon.com/SUPERLELE-Plastic-Graduated-Cylinder-Brushes/dp/B07PXQMQQ5/ref=sr_1_4?crid=OY6NJ8E5T73R&dchild=1&keywords=plastic+graduated+cylinder+set&qid=1591628150&sprefix=plastic+graduated+%2Cautomotive%2C191&sr=8-4
You may also find the following link helpful in looking for alternative ways of cleaning and disinfecting Plexiglass: https://perrybaromedical.com/products/approved-acrylic-products/
How do you clean and maintain the Plexiglas?
As a starter kit, I recommend the following:
The Novus 1 is just a cleaner. It restores that clear shiny look after disinfecting DASH multiple times. This can be done at the end of the day or several times in the middle if desired.
Novus 2 is almost like a light polishing compound that is made for Plexiglas. If you forget to wipe all of the disinfectant off and it dries on, using a small amount of this and a microfiber cloth will get it.
Novus 3 is for deep scratches and is intended to then be followed by Novus 2. We have not had to use this yet. I expect that you will use a fair amount of Novus 1, occasionally Novus 2, and hopefully never need Novus 3.
Is there any additional sources of information?
Yes, I will try to keep the Facebook page current. https://www.facebook.com/Dental-Aerosol-Safety-Hood-106659481082350/
I should receive notification of any questions or posts there. If you are happy with DASH, please tell everyone. This is a grassroots campaign to bring this safety device to our profession. If you are unhappy, please tell me. I have tried very hard to make it as good as possible and have used the input from many doctors and hygienists to make it what it is now. I hope that you will like it and that you will feel safer practicing with it.