Splatters and Aerosols Contamination in Dental Aerosol Generating Procedures

Dental aerosol-generating procedures produce a large amount of splatters and aerosols that create a major concern for airborne disease transmission, such as COVID-19. This study established a method to visualise splatter and aerosol contamination by common dental instrumentation, namely ultrasonic scaling, air-water spray, high-speed and low-speed handpieces. Mock dental procedures were performed on a mannequin model, containing teeth in a typodont and a phantom head, using irrigation water containing fluorescein dye as a tracer. Filter papers were placed in 10 different locations to collect splatters and aerosols, at distances ranging from 20 to 120 cm from the source. All four types of dental equipment produced contamination from splatters and aerosols. At 120 cm away from the source, the high-speed handpiece generated the greatest amount and size (656 ± 551 μm) of splatter particles, while the triplex syringe generated the largest amount of aerosols (particle size: 1.73 ± 2.23 μm). Of note, the low-speed handpiece produced the least amount and size (260 ± 142 μm) of splatter particles and the least amount of aerosols (particle size: 4.47 ± 5.92 μm) at 120 cm. All four dental AGPs produce contamination from droplets and aerosols, with different patterns of distribution. This simple model provides a method to test various preventive strategies to reduce risks from splatter and aerosols.

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

10.31219/osf.io/djcus ◽

2020 ◽

Author(s):

Hayley Llandro ◽

James R Allison ◽

Charlotte Currie ◽

David Edwards ◽

Charlotte Bowes ◽

...

Keyword(s):

Image Analysis ◽

High Speed ◽

Positive Control ◽

Aerosol Generation ◽

Dental Procedures ◽

Air Turbine ◽

Fluorescein Dye ◽

Filter Papers ◽

Crown Preparation ◽

Experimental Rig

Introduction: Dental procedures often produce splatter and aerosol which have potential to spread pathogens such as SARS-CoV-2. Mixed guidance exists on the aerosol generating potential of orthodontic procedures. The aim of this study was to evaluate aerosol and/or splatter contamination during an orthodontic debonding procedure.Material and Methods: Fluorescein dye was introduced into the oral cavity of a mannequin. Orthodontic debonding was carried out in triplicate with filter papers placed in the immediate environment. Composite bonding cement was removed using a slow-speed handpiece with dental suction. A positive control condition included a high-speed air-turbine crown preparation. Samples were analysed using digital image analysis and spectrofluorometric analysis.Results: Contamination across the 8-metre experimental rig was 3% of the positive control on spectrofluorometric analysis and 0% on image analysis. There was contamination of the operator, assistant, and mannequin, representing 8%, 25%, and 28% of the positive control spectrofluorometric measurements, respectively.Discussion: Orthodontic debonding produces splatter within the immediate locality of the patient. Widespread aerosol generation was not observed.Conclusions: Orthodontic debonding procedures are low risk for aerosol generation, but localised splatter is likely. This highlights the importance of personal protective equipment for the operator, assistant, and patient.

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Evaluating dental aerosol and splatter in an open plan clinic environment: implications for the COVID-19 pandemic

10.31219/osf.io/md49f ◽

2020 ◽

Cited By ~ 3

Author(s):

Richard Holliday ◽

James R Allison ◽

Charlotte Currie ◽

David Edwards ◽

Charlotte Bowes ◽

...

Keyword(s):

High Speed ◽

Time Course ◽

Irrigation System ◽

Dilution Effect ◽

Realistic Model ◽

Experimental Conditions ◽

Environmental Cleaning ◽

Open Plan ◽

Fluorescein Dye ◽

Filter Papers

Aim: To identify splatter and aerosol distribution resulting from dental aerosol generating procedures (AGPs) in the open plan clinic environment. A secondary aim is to explore the detailed time course of aerosol settling after an AGP. Methodology: Dental procedures were undertaken on a dental mannequin. Fluorescein dye was placed into the irrigation system of the high-speed air turbine handpiece for the first experimental design, and in the second, fluorescein dye was entered into the mannequin's mouth via artificial salivary ducts. Filter papers were placed at set distances around the open plan clinic environment to collect aerosol and splatter under various mitigating conditions including ventilation and aspiration flow rate. An 8-metre diameter rig was set up to investigate the effect of fallow time. Filter papers were analysed using imaging software and spectrofluorometric analysis. Results: The distribution of fluorescein contamination varied widely across the open plan clinic depending on the experimental conditions. Unmitigated (i.e. no suction) procedures have the potential to deposit contamination at large distances. Medium volume dental suction (159 L/min air) reduced contamination in the AGP bay by 53%, and in adjacent and distant bays/walkways by 81-83%. Low volume suction (40 L/min air) gave similar reductions. Cross-ventilation reduced contamination in adjacent and distant bays/walkways by 80-89%. In the most realistic model (dye in mouth with medium volume suction) the samples in distant bays (≥5 m head-to-head chair distance) either gave zero readings or very low readings (< 0.0016% of the fluorescein introduced into the system during the procedure). Almost all (99.99%) of the splatter detected was retained within the AGP bay/walkway. Time course experiments showed that after 10 minutes, very little additional contaminated aerosol settled. Conclusions: The cross-infection risk from conducting AGPs in an open plan clinic environment appears small, particularly when bays are ≥ 5 m apart. There is a major dilution effect from the instrument water spray and a substantial protective effect from using dental suction. The majority of aerosol settles in the first 10 minutes indicating that environmental cleaning may be appropriate after this time.

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The Efficacy of High-Volume Evacuators and Extraoral Vacuum Aspirators in Reducing Aerosol and Droplet in Ultrasonic Scaling Procedures during the COVID-19 Pandemic

European Journal of Dentistry ◽

10.1055/s-0041-1739448 ◽

2022 ◽

Author(s):

Trijani Suwandi ◽

Vidya Nursolihati ◽

Mikha Sundjojo ◽

Armelia Sari Widyarman

Keyword(s):

Statistical Analysis ◽

High Speed ◽

High Volume ◽

Limited Data ◽

Dental Procedures ◽

Significant Difference ◽

Kolmogorov Smirnov ◽

Airborne Disease ◽

Better Than ◽

Smirnov Test

Abstract Objective SARS-CoV-2 can be carried by aerosols and droplets produced during dental procedures, particularly by the use of high-speed handpieces, air-water syringes, and ultrasonic scalers. High-volume evacuators (HVEs) and extraoral vacuum aspirators (EOVAs) reduce such particles. However, there is limited data on their efficacy. This study aimed to determine the efficacy of HVE and EOVA in reducing aerosols and droplets during ultrasonic scaling procedures. Materials and Methods Three ultrasonic scaling simulations were conducted on mannequins: 1. saliva ejector (SE) was used alone (control); 2. SE was used in combination with HVE; and 3. SE was used in combination with HVE and EOVA. Paper filters were placed on the operator's and assistant's face shields and bodies, and the contamination of aerosols and droplets was measured by counting blue spots on the paper filters. Statistical Analysis All data were analyzed for normality using the Kolmogorov–Smirnov test. The differences between each method were analyzed using a two-way ANOVA, followed by a posthoc test. The differences were considered statistically significant when p < 0.05 Result Using HVE and EOVA reduced aerosols and droplets better than using SE alone or SE and HVE: the posthoc test for contamination revealed a significant difference (p < 0.01). The assistant was subjected to greater contamination than the operator during all three ultrasonic scaling procedures. Conclusion The usage of HVE and EOVA significantly reduced aerosols and droplets compared with using SE solely. Using these techniques together could prevent the transmission of airborne disease during dental cleanings, especially COVID-19. Further studies of aerosol-reducing devices are still needed to ensure the safety of dental workers and patients.

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Risks of Dentistry in Covid 19 - A Review

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v11ispl1.3351 ◽

2020 ◽

Vol 11 (SPL1) ◽

pp. 972-976

Author(s):

Apurva Choudhary ◽

Anjaneyulu K ◽

Smiline Girija A S

Keyword(s):

Public Health ◽

High Speed ◽

Oral Surgery ◽

Dental Procedure ◽

Health Concerns ◽

Infection Transmission ◽

Dental Procedures ◽

Dental Equipment ◽

Dental Practitioners ◽

High Chance

The recent spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its association has gripped the entire community and has caused widespread public health concerns. There are various dental procedures that cause spread of the infection. There are risks due to lack of PPE, risks during dental procedure, risks involving handpiece, aerosols, droplets, during communication and contaminated surface. Minimum 30 articles were collected from Pubmed, Google Scholar. We acknowledge that due to lack of PPE, infection can spread more easily, oral surgery drills also cause aerosol and can be transmitted to the susceptible individuals. Communication between the patient and dentist has a high chance of infection transmission. Contamination from spatter and aerosol dissemination remains a significant hazard to dental personnel when high speed dental equipment is used. Dental practitioners have to be more careful while doing dental procedures as there is a high chance of risks for dentistry during covid-19 and proper guidelines should be there while doing dental procedures.

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A Systematic Review of Droplet and Aerosol Generation in Dentistry

10.1101/2020.08.28.20183475 ◽

2020 ◽

Cited By ~ 1

Author(s):

Nicola Innes ◽

Ilona Johnson ◽

Waraf Al-Yaseen ◽

Rebecca Harris ◽

Rhiannon Jones ◽

...

Keyword(s):

Disease Transmission ◽

High Speed ◽

Oral Surgery ◽

Data Extraction ◽

Transmission Risk ◽

Future Research ◽

Slow Speed ◽

Air Polishing ◽

Aerosol Generation ◽

Dental Procedures

Introduction: Against the COVID-19 pandemic backdrop and potential disease transmission risk by dental procedures that can generate aerosol and droplets. Objectives: This review aimed to identify which clinical dental procedures do generate droplets and aerosols with subsequent contamination, and for these, characterise their pattern, spread and settle. Materials and Method: Six databases were searched and citation chasing undertaken (to 11/08/20). Screening stages were undertaken in duplicate, independently, by two researchers. Data extraction was performed by one reviewer and verified by another. Results: Eighty-three studies met the inclusion criteria and covered: Ultrasonic scaling (USS, n=44), high speed air-rotor (HSAR, n=31); oral surgery (n=11), slow-speed handpiece (n=4); air-water (triple) syringe (n=4), air-polishing (n=4), prophylaxis (n=2) and hand-scaling (n=2). Although no studies investigated respiratory viruses, those on bacteria, blood splatter and aerosol showed activities using powered devices produced the greatest contamination. Contamination was found for all activities, and at the furthest points studied. The operator torso operator arm, and patient body were especially affected. Heterogeneity precluded significant inter-study comparisons but intra-study comparisons allowed construction of a proposed hierarchy of procedure contamination risk: higher risk (USS, HSAR, air-water syringe [air only or air/water together], air polishing, extractions using motorised hand-pieces); moderate (slow-speed handpieces, prophylaxis with pumice, extractions) and lower (air-water syringe [water only] and hand scaling. Conclusion: Significant gaps in the evidence, low sensitivity of measures and variable quality limit firm conclusions around contamination for different procedures. However, a hierarchy of contamination from procedures can be proposed for challenge/verification by future research which should consider standardised methodologies to facilitate research synthesis. Clinical significance (49 words): This manuscript addresses uncertainty around aerosol generating procedures (AGPs) in dentistry. Findings indicate a continuum of procedure-related aerosol generation rather than the current binary AGP or non-AGP perspective. This informs discussion around AGPs and direct future research to help support knowledge and decision making around COVID-19 and dental procedures.

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Changes in solid particle fractions of coating color in low- and high-speed blade coating

TAPPI Journal ◽

10.32964/tj12.6.31 ◽

2013 ◽

Vol 12 (6) ◽

pp. 31-38

Author(s):

ANNE RUTANEN ◽

MARTTI TOIVAKKA

Keyword(s):

Particle Size ◽

Solid Particle ◽

High Speed ◽

Volume Fraction ◽

Cohesion Energy ◽

Size Segregation ◽

Particle Segregation ◽

Low Speed ◽

Coating Color ◽

Solids Content

Changes in coating color composition in a recirculation loop of a coater can cause runnability and paper quality variability. Besides an increase in the coating color solids content, the average size of the solid particles increases as a result of depletion of fine materials or shear-induced aggregation. The mechanisms for changes in solid particle fractions of coating colors and control parameters are not well understood or documented. Previous work has investigated the role of coating color solids content and cohesion energy in particle segregation tendencies by using a low-speed laboratory coater. The current work extends the study to high-speed pilot-scale coating and compares the results to the laboratory-scale coater. It is proposed that similar results in regard to particle size segregation can be observed with both a low-speed laboratory coater and a high-speed pilot coater. The same parameters, such as solids volume fraction, control the particle size segregation regardless of the speed and the applicator type. If the solids volume fraction and the packing volume are high, the coating color cohesion energy is not of importance for particle segregation.

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

10.1101/2020.08.19.20178319 ◽

2020 ◽

Author(s):

Hayley Llandro ◽

James R Allison ◽

Charlotte C Currie ◽

David C Edwards ◽

Charlotte Bowes ◽

...

Keyword(s):

Image Analysis ◽

High Speed ◽

Digital Image Analysis ◽

Positive Control ◽

List Type ◽

Dental Procedures ◽

Air Turbine ◽

Fluorescein Dye ◽

Crown Preparation ◽

Experimental Rig

AbstractIntroductionDental procedures produce splatter and aerosol which have potential to spread pathogens such as SARS-CoV-2. Mixed evidence exists on the aerosol generating potential of orthodontic procedures. The aim of this study was to evaluate splatter and/or settled aerosol contamination during orthodontic debonding.Material and MethodsFluorescein dye was introduced into the oral cavity of a mannequin. Orthodontic debonding was undertaken with surrounding samples collected. Composite bonding cement was removed using a speed-increasing handpiece with dental suction. A positive control condition included a water-cooled, high-speed air-turbine crown preparation. Samples were analysed using digital image analysis and spectrofluorometric analysis.ResultsContamination across the 8-metre experimental rig was 3% of the positive control on spectrofluorometric analysis and 0% on image analysis. Contamination of the operator, assistant, and mannequin, was 8%, 25%, and 28% of the positive control, respectively.DiscussionSplatter and settled aerosol from orthodontic debonding is distributed mainly within the immediate locality of the mannequin. Widespread contamination was not observed.ConclusionsOrthodontic debonding is unlikely to produce widespread contamination via splatter and settled aerosol, but localised contamination is likely. This highlights the importance of personal protective equipment for the operator, assistant, and patient. Further work is required to examine suspended aerosol.Three ‘In brief’ pointsOrthodontic debonding, including removal of composite using a slow speed handpiece with dental suction, appears to pose little risk of widespread distribution of settled contamination.Splatter and settled aerosol was produced during the debonding procedure, however this was mainly localised to the patient, operator and assistant.Further work is required to examine aerosol which remains suspended in the air.

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Dental Aerosol as a Hazard Risk for Dental Workers

Materials ◽

10.3390/ma13225109 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5109

Author(s):

Jacek Matys ◽

Kinga Grzech-Leśniak

Keyword(s):

High Speed ◽

Dental Treatment ◽

Er:Yag Laser ◽

High Volume ◽

Low Speed ◽

Dental Procedures ◽

Dental Office ◽

Study Results ◽

Caries Removal ◽

Bacteria And Fungi

Standard dental procedures, when using a water coolant and rotary instruments, generate aerosols with a significantly higher number of various dangerous pathogens (viruses, bacteria, and fungi). Reducing the amount of aerosols to a minimum is mandatory, especially during the new coronavirus disease, COVID-19. The study aimed to evaluate the amount of aerosol generated during standard dental procedures such as caries removal (using dental bur on a high and low-speed handpiece and Er:YAG laser), ultrasonic scaling, and tooth polishing (using silicon rubber on low-speed handpiece) combined with various suction systems. The airborne aerosols containing particles in a range of 0.3–10.0 μm were measured using the PC200 laser particle counter (Trotec GmbH, Schwerin, Germany) at three following sites, manikin, operator, and assistant mouth, respectively. The following suction systems were used to remove aerosols: saliva ejector, high volume evacuator, saliva ejector with extraoral vacuum, high volume evacuator with extraoral vacuum, Zirc® evacuator (Mr.Thirsty One-Step®), and two customized high volume evacuators (white and black). The study results showed that caries removal with a high-speed handpiece and saliva ejector generates the highest amount of spray particles at each measured site. The aerosol measurement at the manikin mouth showed the highest particle amount during caries removal with the low and high-speed handpiece. The results for the new high volume evacuator (black) and the Zirc® evacuator showed the lowest increase in aerosol level during caries removal with a high-speed handpiece. The Er:YAG laser used for caries removal produced the lowest aerosol amount at the manikin mouth level compared to conventional dental handpieces. Furthermore, ultrasonic scaling caused a minimal aerosol rise in terms of the caries removal with bur. The Er:YAG laser and the new wider high volume evacuators improved significantly suction efficiency during dental treatment. The use of new suction systems and the Er:YAG laser allows for the improvement of biological safety in the dental office, which is especially crucial during the COVID-19 pandemic.

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Evaluating aerosol and splatter following dental procedures: addressing new challenges for oral healthcare and rehabilitation

10.1101/2020.06.25.154401 ◽

2020 ◽

Author(s):

James R Allison ◽

Charlotte C Currie ◽

David C Edwards ◽

Charlotte Bowes ◽

Jamie Coulter ◽

...

Keyword(s):

High Speed ◽

Descriptive Statistics ◽

Analytic Methods ◽

Clinical Procedures ◽

Post Procedure ◽

Dental Procedures ◽

Air Turbine ◽

Low Levels ◽

Filter Papers ◽

The Impact

AbstractBackgroundDental procedures often produce aerosol and splatter which are potentially high risk for spreading pathogens such as SARS-CoV-2. The existing literature is limited.Objective(s)To develop a robust, reliable and valid methodology to evaluate distribution and persistence of dental aerosol and splatter, including the evaluation of clinical procedures.MethodsFluorescein was introduced into the irrigation reservoirs of a high-speed air-turbine, ultrasonic scaler and 3-in-1 spray and procedures performed on a mannequin in triplicate. Filter papers were placed in the immediate environment. The impact of dental suction and assistant presence were also evaluated. Samples were analysed using photographic image analysis, and spectrofluorometric analysis. Descriptive statistics were calculated and Pearson’s correlation for comparison of analytic methods.ResultsAll procedures were aerosol and splatter generating. Contamination was highest closest to the source, remaining high to 1-1.5 m. Contamination was detectable at the maximum distance measured (4 m) for high-speed air-turbine with maximum relative fluorescence units (RFU) being: 46,091 at 0.5 m, 3,541 at 1.0 m, and 1,695 at 4 m. There was uneven spatial distribution with highest levels of contamination opposite the operator. Very low levels of contamination (≤0.1% of original) were detected at 30 and 60 minutes post procedure. Suction reduced contamination by 67-75% at 0.5-1.5 m. Mannequin and operator were heavily contaminated. The two analytic methods showed good correlation (r=0.930, n=244, p<0.001).ConclusionDental procedures have potential to deposit aerosol and splatter at some distance from the source, being effectively cleared by 30 minutes in our setting.

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Do You Name Speedy Objects Faster Than Slow Objects: SPEEDED NAMING OR NAMING SPEED? THE AUTOMATIC EFFECT OF OBJECT SPEED ON PERFORMANCE

10.31234/osf.io/78b3h ◽

2018 ◽

Author(s):

Moshe Shay Ben-Haim ◽

Eran Chajut ◽

Ran Hassin ◽

Daniel Algom

Keyword(s):

High Speed ◽

Mental Representations ◽

Reading Aloud ◽

Naming Task ◽

Naming Speed ◽

Low Speed ◽

Everyday Objects ◽

Pictures And Words

we test the hypothesis that naming an object depicted in a picture, and reading aloud an object’s name, are affected by the object’s speed. We contend that the mental representations of everyday objects and situations include their speed, and that the latter influences behavior in instantaneous and systematic ways. An important corollary is that high-speed objects are named faster than low-speed objects despite the fact that object speed is irrelevant to the naming task at hand. The results of a series of 7 studies with pictures and words support these predictions.

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