Effectiveness of Preprocedural Mouthwashes: A Triple-Blind Randomised Controlled Clinical Trial

Area of Science:

• Dental Research
• Infectious Disease Control
• Public Health Policy

Background:

• Bioaerosols from dental procedures can transmit respiratory pathogens.
• Preprocedural mouthwashes are proposed to decrease microbial load.
• Evidence on their effectiveness against respiratory pathogens is limited.

Purpose of the Study:

• To evaluate the efficacy of three preprocedural mouthwashes in mitigating respiratory pathogens during dental care.
• To compare povidone-iodine, hydrogen peroxide, and chlorhexidine digluconate mouthwashes.
• To inform public health recommendations during pandemics.

Main Methods:

• A triple-blind randomized clinical trial involving 228 participants.
• Participants used povidone-iodine, hydrogen peroxide, or chlorhexidine digluconate mouthwash.
• Saliva samples were analyzed for 19 respiratory viruses, including SARS-CoV-2, pre- and post-procedure.

Main Results:

• Overall prevalence of respiratory viral pathogens decreased from 3.5% to 1.3% post-mouthwash (P = .034).
• The mean number of detected viruses significantly lowered after mouthwash use (P = .025).
• No significant differences were found between the specific mouthwash types regarding pathogen reduction.

Conclusions:

• Preprocedural mouthwash use effectively reduces respiratory pathogens in dental aerosol-generating procedures.
• Findings support the Hong Kong Department of Health's policy on preprocedural mouthwashes.
• This practice has important implications for infection control during pandemics.