During COVID-19 times, as dental clinics lumber back slowly to reopening, we have to get used to the ‘new normal’. The first thing we start thinking is, are we well prepared? The most basic of this is what mask to use in dentistry.
We have been using a 3-ply surgical mask all our lives. The question is, is it enough in COVID-19 times?
Keep in mind we are going to discuss about consulting and working (including aerosol procedures) in a dental clinic here.
How to choose a N95 Respirator?
| Respirator Standard | Filter Capacity |
| FFP1 & P1 | At least 80% |
| FFP2 & P2 | At least 94% |
| N95 | At least 95% |
| N99 & FFP3 | At least 99% |
| P3 | At least 99.95% |
| N100 | At least 99.97% |
FFP (Filtering Face Piece) is the European Standard, N is the American (NIOSH) standard and KN is the Chinese Standard.
In essence,
FFP2 = N95 = KN95.
There are also Korean 1st Class and Japanese DS FFRs which are also comparable standards.
POINTS TO NOTE:
- Choose a N95 or comparable standard.
- Once you enter your clinic, remove the mask you wore outside and put on a N-95 respirator.
- It should have a elastic head Loop and not a ear loop, as the fit over face improves in case of head loop. KN95 have ear loop, though they can be tightened behind the ear with a clip etc.
- Avoid one with Valve. Valves helps in Exhaling better but doesn’t filter the air efficiently while exhaling , thereby increasing the chance of transmission to patients.
- Definitely, a nose clip should be present.
- It’s better to have no facial hair, mostly around the area of seal, to prevent any leakage.
Do you need a surgical N95 respirator?
If you can find one, may be. Surgical respirator is fluid resistant to a pressure of 120-160 mmHg. They don’t allow aerosol to pass through and are ideal in dentistry. Problem is, it’s difficult to dry and sterilize a moist respirator and you will probably have to discard it.
So what about aerosol procedures?
It is better to wear a 3-ply surgical mask, tie type, with nose clip and having a melt-blown (plastic impregnated) layer over the N95 respirator during a aerosol procedure. This 3-ply mask can then be discarded.
How to sterilize or Reuse N-95 respirator?
As the commonly available N95 respirator (like 3M 8210) is a non-surgical respirator without valve, long term use, results in the inside of the respirator becoming moist with perspiration.
It can be dried in air or sun and can be reused. You can even sterilize it using UVC light. Do not wash it. Between use, it can be stored in a clean paper bag.
When to discard your N95 respirator?
- Once it becomes visibly dirty or wet.
- When it gets difficult to breathe, meaning thereby the filtration mechanism has become clogged.
- Current guidelines suggest use up to 5 days to be safe.
TIP: Have 5 N95 respirators. Use 1, store it for next 4 days. Use the other 4 N95 respirator, one each day and store them for 4 days. Current literature suggests, COVID19 virus can survive on some surfaces for up to 4 days. Remember to store each in separate paper bags and label them.
Some Available N-95 Respirators suitable in dentistry:
