https://plastcareusa.com/general/rules-history-of-bingo/
One of the most important aspects of a dental face mask is the level. The American Society For Testing and Materials (ASTM) has statutorily defined mask levels and which mask should be worn in different procedures. Masks are grouped into level 1, level 2, and level 3.
Level 1 masks are generally considered as a low barrier. They are designed for procedures with a low amount of fluid, blood, aerosol exposure or spray. Plus, they are latex or fiberglass free. Examples include impressions, operatory cleaning, patient exams, orthodontic work, as well as lab trimming.
On the other hand, level 2 masks are considered as a moderate barrier. They are suitable for procedures with light or moderate amount of blood, fluid, aerosols or spray are produced. Examples include sealants, prophylaxis, restoratives, endodontic work, and limited oral surgery. Just like level 1 masks, level 2 masks are also latex or fiberglass free.
Lastly, level 3 masks are considered a high barrier. They are ideal for procedures with a moderate or high amount of fluid, blood, aerosols or spray exposure. Common procedures where level 3 masks are suitable include implant placement, complex oral surgery, and crown preparation. Level 3 masks are available in white, pink, and blue colors.
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