Removal efficiency of central vacuum system and protective masks to suspended particles from dental treatment

Abstract

BackgroundHigh levels of suspended particulate matters (PMs) and bioaerosols are created by dental procedures. The present study aimed to evaluate the size and concentration of PMs produced by drilling and grinding teeth, and to assess the efficiency of central vacuum system and protective masks for the removal of PMs.MethodsA total of 20 extracted permanent teeth were collected. A novel experimental system and particle counter were used to evaluate the PMs produced by dental procedures and the PM removal efficiency of a central vacuum system and surgical/N95 masks.ResultsThe number concentration of total PMs produced by drilling and grinding teeth was significantly higher than the indoor background concentration. The average aerodynamic diameter of particle was generally less than 1 μm. The average number concentration of ultrafine particles was 2.1x1011 particles/m3 during tooth drilling and grinding. The efficiency of the central vacuum system was 35.74% for PM≥0.5 and 35.41% for PM10. For PM≥0.5, the ratios of inside and outside masks were 0.8–1.34 without vacuum and 1.18–1.36 with vacuum. No difference was found with the use of surgical/N95 masks during dental therapy, with or without vacuum use.ConclusionsHigh levels of PMs were found during tooth drilling and grinding procedures, especially among PM1. The PM removal efficiency of a central vacuum system and surgical/N95 masks were limited.

Effects of mechanical ventilation and portable air cleaner on aerosol removal from dental treatment rooms

“…Before the experiment, we measured the aerosol concentrations near the breathing zone of the operators in dental treatment rooms during restorative and surgical procedures and found that most of the aerosol particles generated by high and low-speed dental drillings were below 1.0 μm in diameter (Supplemental Fig. 1, Supplemental Tables 1 and 2), which is consistent with the reports that aerosol particles from drilling activities in dental treatment rooms were mostly smaller than 0.5 μm in diameter and particles larger than 1 μm were rare [ [29] , [30] , [31] ]. A small oscillating fan mounted on the walls was turned on at low setting during the experiment to render the air well mixed in the dental treatment rooms.…”

Mitigating saliva aerosol contamination in a dental school clinic

“…Although several studies intended to assess the dissemination of aerosol by measuring bacterial contamination in the dental operatory [9,17,18], only a handful of studies directly measured the aerosol's dissemination [19][20][21]. However, these studies either measured the aerosol level in the whole area of dental office which includes multiple dental chairs/operatories, or measured the generation of aerosols in a long period of time (ranged from a day to a week) [20,21].…”

“…However, these studies either measured the aerosol level in the whole area of dental office which includes multiple dental chairs/operatories, or measured the generation of aerosols in a long period of time (ranged from a day to a week) [20,21]. In addition, some studies used manikin or extracted teeth instead of patients [12,19], which failed to simulate dental aerosols that contains a mixture of patient's saliva and fluid with compressed air and water. To the best of our knowledge, there is no published quantitative evidence on the distribution of size and concentration of aerosols in an individual dental operatory during a specific dental procedure.…”

Evaluating splatter and settled aerosol during orthodontic debonding: implications for the COVID-19 pandemic

“…contamination 28,29,30,31,32,33,34,35 and the use of optical particle-counting instruments. 36,37 Various definitions exist for the terms 'aerosol' and 'splatter' . One classification described in the literature defines aerosol droplets as having a diameter of less than 10 μm, 38 with splatter comprising droplets larger than this.…”