Changes in the Oral Cavity Mucosal Surface under the Influence of Wearing Protective Face Masks—Nitric Oxide Concentration Analysis—Preliminary Report

Abstract

Orders to cover the mouth and nose were introduced as a prophylaxis for COVID-19. The use of face masks, apart from their benefits, has some side effects. It can affect, among other things, the oral cavity mucosa, manifested by its dryness, and can increase the amount of inflammatory markers, for example, nitric oxide (NO). The aim of this research was to determine changes in the oral cavity mucosal surface under the influence of the use of protective face masks based on an innovative measurement of NO levels in the exhaled air of healthcare workers. The people taking part in this study were dental assistants and recorders who used masks during work. The first measurement of NO was carried out before starting work and putting on a mask, and the second measurement was carried out after work. Based on the research, a statistically significant difference was shown in the NO values before putting on a mask and immediately after removing it. Despite the advantages of wearing protective masks, studies have shown that their long-term use has an impact on the oral cavity mucosa, which is reflected in the higher level of NO in exhaled air.

The Bacterial Burden of Worn Face Masks – Observational Research and Literature Review

“…These then may be projected or inhaled with every breath [17,[108][109][110][116][117][118]. In this context, we underscore the predominantly oral breathing while wearing a mask [17,119], in contrast to normal unimpeded breathing, which is largely via the nose, with greater filtration. Oral breathing increases the hazard of directly inhaling microorganisms from the mask into the deeper airways [120].…”

Wearing Face Masks as a Potential Source for Inhalation and Oral Uptake of Inanimate Toxins: a Scoping Review

“…Special consideration must be given to the fact that due to increased breathing resistance wearing a mask can cause substantial damage to nasal airflow [26,122]. Due to the presence of the mask, people have a natural tendency to breathe through the open mouth which means less breathing resistance bypassing the nasal airflow [26,27]. Usually under natural nose breathing [123] particles impact further up the respiratory airways depositing in a size-dependent manner from the nasal passages to the larger bronchioles.…”

“…This relationship (particle size-depth of diffusion and deposition) is constant across humans [123,124]. Most humans incline to revert to oral breathing during mask wearing [26,27]. This significantly increases the amount and size of particles that may be directly inhaled into the bronchi and lungs due to bypassing the filtration of the nasal cavity [125].…”

“…Humans inhale emissions from a mask at nearly zero distance and swallow water droplets originating from the moist dead space enriched with mask ingredients. In this regard -theoretically -wearing a mask may exert a higher risk of exposure than many other environmental sources [25], keeping in mind the predominantly oral breathing while wearing a mask [26,27].…”