Can toothbrushing reduce the intraoral viral load of SARS-CoV-2? A pilot study with a dentifrice containing an antimicrobial phthalocyanine derivative.

ABSTRACT

The aim of this study was to assess whether toothbrushing with a dentifrice containing an antimicrobial phthalocyanine derivative (APD) can reduce the intraoral viral load of SARS-CoV-2. Twenty COVID-19-positive dentate patients aged ≥18 years were selected instructed to brush their teeth for 2 min with a dentifrice containing APD. Self-collected samples of unstimulated saliva were carried out three times T0 (baseline), T5 (5 min after toothbrushing), and T30 (30 min after toothbrushing). The analysis of viral RNA was performed by RT-qPCR for detection of three viral genes (ORF1ab, N and S genes). Results were statistically tested using Friedman's test and pairwise comparison with Bonferroni corrections, with a significance level of 5%. There was an increase in the cycle threshold (Ct) value from T0 to T5 in 13 patients (72.2%), and from T0 to T30 in 14 patients (77.8%). In two patients (11.1%) no SARS-CoV-2 was detected at T5 and five patients (27.8%) at T30. The Ct values were statistically significantly higher (p=0.020) at T30 in comparison to T0 and T5. This pilot study suggests that toothbrushing with a dentifrice containing APD could reduce the SARS-CoV-2 viral load in the oral cavity. However, further studies are needed to confirm this possible beneficial effect against SARS-CoV-2.