[STUDY] Aerosols in the Dental Office: Best Practices for Patient and Practitioner Safety

COVID 19 originate

• Wuhan china (not confirmed)

• Virus found in horseshoe bats and pangolins

• Zoonotic transmission

Aerosols vs splatters

Aerosols

• Less than 50 μm

• Suspended

• Travel >3 ft

• Greater infection risk

• Inhaled

• Produced by high speed handpieces, ultrasonic scalers, air—water syringe

Splash/splatters

• Greater than 50 μm

• Falls quickly

• Travel less than 3 ft

Patient source

Saliva, dental plaque, respiratory bacteria, tooth debris

• Dental plaque contains 700 known microorganisms

People thought fomites were a major transmission route

• Suface transmission risk — overestimated

• Aerosols — From dental irrigants (not saliva)

• Salivary — low or undetectable

COVID characteristics

• Large

• Single stranded RNA

• B—coronavirus family

• Spike (S—protein) — attach to human cells

• Uses receptor ACE2 (Angiotensin converting enzyme 2)

  • Expression increase w/ age

• RNA mutates rapidly (increase infection, longer survival, replication)

• Average 5 days after first symptom

• Spread by respiratory / direct

• ACE2 receptors — abundant in salivary and respiratory glands

Later findings

Dental care — low transmission risk

• Aerosols contain low microbial

• Aerosol generating — same COVID transmission risk as non aerosols

Antiseptic mouthrinses

• Hydrogen peroxide

• Chlorhexidine

• Cetylpyridinium chloride (CPC)

• Povidone iodine

= at least 30 secs

Reduces COVID in mouth in vitro

in vivo — no benefit

How to reduce dental aerosols

• HEPA Filter with extraoral suction

• Portable air cleaners