Female patient about to take a sip of mouthrinse

Pre-Procedural Rinsing in the time of COVID-19

Date: June 2020

Author: Louise Sinclair

SARS-CoV-2, the virus that causes COVID-19, is believed to be transmitted primarily via droplets and aerosols, as well as through contact, presenting an enhanced risk of transmission in the dental office. As a dental hygienist returning to work, you can help minimize this risk for yourself, your colleagues and your patients. Protocols include screening, social distancing and appropriate personal protective equipment.

Pre-procedural rinsing has also been suggested. Before discussing this, we should note there is currently no documented evidence that the use of pre-procedural rinses reduces SARS-CoV-2 viral loads or transmission of SARS-CoV-2, as highlighted in the interim guidance from the American Dental Association and the Centers for Disease Control and Prevention.

Several antimicrobial rinses have been used for pre-procedural rinsing, such as chlorhexidine gluconate, however they were tested for bacterial load reduction, not viral load reduction. As such, we can only hypothesize about the efficacy of pre-procedural mouthrinses in reducing COVID-19 transmission, based on their known modes of action.

An article from the International Journal of Oral Science suggests that chlorhexidine mouthrinses may not be effective against SARS-CoV-2. The authors recommend a pre-procedural mouthrinse with an oxidative agent, such as 1% hydrogen peroxide, pointing out that the virus is vulnerable to oxidation. Hydrogen peroxide produces hydroxyl free radicals that are known to attack the lipid “capsule” of enveloped viruses and the genetic material inside. It has been shown to have a virucidal effect in vitro on other coronaviruses.

When considering the potential and as yet undefined risk of transmission from dental aerosols, the safe history of use, availability and affordability of a 1.5% hydrogen peroxide mouthrinse, such as Colgate® Peroxyl®, makes it an attractive precautionary measure.

Pre-procedural rinsing has been recommended previously as a protocol to reduce bacterial loads in dental aerosols. With the support of your employer, you can offer to take the lead in educating the dental team about the potential benefits of mouthrinses like Colgate® Peroxyl®. Remember, too, to let everyone know that pre-procedural rinsing is an off-label use for mouthrinses. It may help to share resources such as those provided in this article, emphasizing the mechanism of action as a rationale for why pre-procedural rinsing may be helpful.

As the COVID-19 pandemic continues and we attempt to navigate the safe re-opening of our dental offices, now is a good time to consider pre-procedural mouthrinsing a standard part of every procedure.