SARS‐CoV‐2 RNA in dental biofilms: Supragingival and subgingival findings from inpatients in a COVID‐19 intensive care unit

Abstract

Background Saliva, salivary glands, gingival crevicular fluid, and supragingival biofilms may harbor SARS‐CoV‐2 RNA. This observational study aimed to investigate the presence and load of SARS‐CoV‐2 RNA in supragingival, and subgingival biofilms obtained from intensive care unit (ICU) patients. Methods A convenience sample, composed of 52 COVID‐19+ participants (48.6 ± 14.8 years, 26.9% females), were evaluated for pre‐existing comorbidities, number of teeth, and periodontal data [visible plaque (VPI), bleeding on probing (BOP), periodontal probing depth (PPD), and attachment loss (AL)]. Supragingival and subgingival samples (SubDeep: four sites with the deepest PPD; SubRemain: remaining shallower sites) were analyzed by RT‐qPCR with corresponding cycle quantification (Cq). Statistical analyses considered the individual ( P = 5%). Results Twenty‐six participants tested positive for dental biofilms (Biofilm+) with 96.2% of them being positive for subgingival samples. Pre‐existing comorbidities, number of teeth examined, VPI, PPD, AL, and BOP were similar between Biofilm+ and Biofilm‐. SubDeep PPD (3.72 ± 0.86), AL (4.34 ± 1.33), and % of BOP (66.0 ± 31.1) values were significantly greater compared to SubRemain values (2.84 ± 0.48, 3.37 ± 0.34, and 20.4 ± 24.1, respectively). Biofilm+ Cqs showed no association with the periodontal condition. Cqs from Nasopharynx/Oropharynx (Naso/Oro; n = 36) were similar between Biofilm+ and Biofilm‐ participants. Length of time since ICU intake, last Naso/Oro RT‐qPCR readings, onset of COVID‐19 symptoms, and biofilm samplings were greater for Biofilm‐. Conclusions ICU patients harbored SARS‐CoV‐2 RNA in supragingival and subgingival biofilms, irrespective of the periodontal condition, and systemic viral load. The high number of positive patients highlights the need to better understand this habit to provide adequate oral care.

Clinical, immunological, and microbiological analysis of the association between periodontitis and COVID-19: a case–control study

“…In our study, periodontal examination was performed during the infection and the diagnosis of periodontitis was based on PD, CAL, and tooth loss; moreover, a matched control group was included. In contrast, some studies did not perform clinical periodontal examination [ 8 , 9 ], did not include a control group [ 12 , 35 ], and only evaluated patients after the infection [ 10 ]. Multivariate analysis showed that even after the removal of confounders, periodontitis persisted as a significant factor regarding the need of hospitalization.…”

Biofilms possibly harbor occult SARS-CoV-2 may explain lung cavity, re-positive and long-term positive results

“…Characteristics of cases that SARS-CoV-2 co-infects with other pathogens include venerable age, glucocorticoid therapy, immunocompromised state, long-term antibiotic use history, diabetes, cardiovascular comorbidities, intensive care unit attending, ventilation treatment, prolonged hospitalization time, and exacerbation of symptoms ( Bao et al., 2020 ; Blasco et al., 2020 ; Contou et al., 2020 ; Wang et al., 2020a ; Alhumaid et al., 2021 ; He et al., 2021 ; Yasmin et al., 2021 ; Gomes et al., 2022 ; Hedberg et al., 2022 ; Ortega-Pena et al., 2022 ; Rouze et al., 2022 ; SeyedAlinaghi et al., 2022 ; Shetty et al., 2022 ). Bacterial pathogens generally isolated cover M. pneumoniae , P. aeruginosa , H. influenzae , K. pneumoniae and S. pneumoniae ( Lansbury et al., 2020 ).…”

“…Abundant cases of SARS-CoV-2 co-infection with other microorganisms have been reported, which were associated with venerable age, immunosuppression, cardiovascular disease, diabetes, intensive care unit attending, mechanical ventilation treatment, long-term antibiotic use, glucocorticoid therapy, prolonged hospitalization, exacerbation of symptoms, and poor prognosis ( Bao et al., 2020 ; Blasco et al., 2020 ; Contou et al., 2020 ; Wang et al., 2020a ; Alhumaid et al., 2021 ; He et al., 2021 ; Yasmin et al., 2021 ; Gomes et al., 2022 ; Hedberg et al., 2022 ; Ortega-Pena et al., 2022 ; Rouze et al., 2022 ; SeyedAlinaghi et al., 2022 ; Shetty et al., 2022 ). M. pneumoniae , P. aeruginosa , H. influenzae , and K. pneumoniae are bacterial co-pathogens usually detected ( Lansbury et al., 2020 ).…”

“…The result revealed that SARS-CoV-2 RNA were positive in 13 biofilm samples. Their another study showed that SARS-CoV-2 RNA was detected in oral biofilms in 26 out of 52 COVID-19 patients from the ICU, and it’s turn out that 96.2% positive samples were from subgingival specimens ( Gomes et al., 2022 ). Furthermore, there are also other kinds of viral components within dental plaque ( Das et al., 2012 ; Edlund et al., 2015 ), such as bacteriophage, herpes simplex virus (HSV) and Epstein-Barr virus (EBV) etc.…”

Unvaccinated periodontal patients with a history of COVID-19: clinical findings in a Dental School setting

“…SARS-CoV-2 can be found in many sites in the oral cavity, such as mucosal cells and tissues, saliva, supra and subgingival biofilms, and gingival crevicular fluid. 8 ),( 9 ),( 10 As the virus has an airborne transmission, dental care had to undergo several adaptations to avoid its dissemination. 11 For biosafety reasons, Dental Schools were closed for patients for several months.…”