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Ma X, Kim WH, Lee JH, Han DW, Lee SH, Kim J, Lee D, Kim B, Shin DM. The Effectiveness of a Novel Air-Barrier Device for Aerosol Reduction in a Dental Environment: Computational Fluid Dynamics Simulation. Bioengineering (Basel) 2023; 10:947. [PMID: 37627832 PMCID: PMC10452020 DOI: 10.3390/bioengineering10080947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
The use of equipment such as dental handpieces and ultrasonic tips in the dental environment has potentially heightened the generation and spread of aerosols, which are dispersant particles contaminated by etiological factors. Although numerous types of personal protective equipment have been used to lower contact with contaminants, they generally do not exhibit excellent removal rates and user-friendliness in tandem. To solve this problem, we developed a prototype of an air-barrier device that forms an air curtain as well as performs suction and evaluated the effect of this newly developed device through a simulation study and experiments. The air-barrier device derived the improved design for reducing bioaerosols through the simulation results. The experiments also demonstrated that air-barrier devices are effective in reducing bioaerosols generated at a distance in a dental environment. In conclusion, this study demonstrates that air-barrier devices in dental environments can play an effective role in reducing contaminating particles.
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Affiliation(s)
- Xiaoting Ma
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam 999077, Hong Kong;
| | - Won-Hyeon Kim
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Republic of Korea; (W.-H.K.); (S.-H.L.); (J.K.); (D.L.)
| | - Jong-Ho Lee
- Daan Korea Corporation, Seoul 06252, Republic of Korea;
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Republic of Korea;
| | - Sung-Ho Lee
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Republic of Korea; (W.-H.K.); (S.-H.L.); (J.K.); (D.L.)
| | - Jisung Kim
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Republic of Korea; (W.-H.K.); (S.-H.L.); (J.K.); (D.L.)
| | - Dajung Lee
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Republic of Korea; (W.-H.K.); (S.-H.L.); (J.K.); (D.L.)
| | - Bongju Kim
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul 03080, Republic of Korea; (W.-H.K.); (S.-H.L.); (J.K.); (D.L.)
| | - Dong-Myeong Shin
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam 999077, Hong Kong;
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Sayahi T, Workman AD, Kelly KE, Ardon-Dryer K, Presto AA, Bleier BS. Aerosol Generation During Nasal Airway Instrumentation. Otolaryngol Head Neck Surg 2023; 168:506-513. [PMID: 35503253 DOI: 10.1177/01945998221099028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 04/18/2022] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Airborne aerosol transmission, an established mechanism of SARS-CoV-2 spread, has been successfully mitigated in the health care setting through the adoption of universal masking. Upper airway endoscopy, however, requires direct access to the face, thereby potentially exposing the clinic environment to infectious particles. This study quantifies aerosol production during rigid nasal endoscopy (RNE) and RNE with debridement (RNED) as compared with intubation, a posited gold standard aerosol-generating procedure. STUDY DESIGN Prospective cross-sectional study. SETTING Subspecialty single-center clinic and surgical study. METHOD Three aerosol detectors (NANOSCAN-3910, OPS-3330, and APS-3321) with a particle size sensitivity of 10 to 20,000 nm were utilized to detect particulate production during the clinical care of 209 patients undergoing RNE/RNED and 25 patients undergoing intubation. RESULTS RNE and RNED produced statistically significant particles over baseline in 29.3% and 51.0% of subjects (P = .003-.049 and .002-.047, respectively). Intubation produced statistically significant particles in 31.2% (P = .001-.015). The mean ± SD particle diameter in all tests was 69.9 ± 10.5 nm with 99.7% <300 nm. There were no statistical differences in particle production among RNE, RNED, and intubation. The presence of concomitant cough, sneeze, or prolonged speech similarly did not significantly affect particle production during any procedure. CONCLUSIONS Instrumentation of nasal airway produces airborne aerosols to a similar degree of those seen during intubation, independent of reactive patient behaviors such as cough or sneeze. These data suggest that an improved understanding is necessary of both the definition of an aerosol-generating procedure and the functional consequences of procedural aerosol generation in clinical settings.
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Affiliation(s)
- Tofigh Sayahi
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Alan D Workman
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Kerry E Kelly
- Department of Chemical Engineering, University of Utah, Salt Lake City, Utah, USA
| | - Karin Ardon-Dryer
- Department of Geosciences, Texas Tech University, Lubbock, Texas, USA
| | - Albert A Presto
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Benjamin S Bleier
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
- Consultant for Inquis Medical, Inc, Redwood City, California, USA
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3
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Kayahan E, Wu M, Van Gerven T, Braeken L, Stijven L, Politis C, Leblebici ME. Droplet size distribution, atomization mechanism and dynamics of dental aerosols. JOURNAL OF AEROSOL SCIENCE 2022; 166:106049. [PMID: 35891888 PMCID: PMC9304037 DOI: 10.1016/j.jaerosci.2022.106049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/03/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Since the outbreak of COVID-19 pandemic, maintaining safety in dental operations has challenged health care providers and policy makers. Studies on dental aerosols often focus on bacterial viability or particle size measurements inside dental offices during and after dental procedures, which limits their conclusions to specific cases. Fundamental understanding on atomization mechanism and dynamics of dental aerosols are needed while assessing the risks. Most dental instruments feature a build-in atomizer. Dental aerosols that are produced by ultrasonic or rotary atomization are considered to pose the highest risks. In this work, we aimed to characterize dental aerosols produced by both methods, namely by Mectron PIEZOSURGERY® and KaVo EXPERTtorque™. Droplet size distributions and velocities were measured with a high-speed camera and a rail system. By fitting the data to probability density distributions and using empirical equations to predict droplet sizes, we were able to postulate the main factors that determine droplet sizes. Both dental instruments had wide size distributions including small droplets. Droplet size distribution changed based on operational parameters such as liquid flow rate or air pressure. With a larger fraction of small droplets, rotary atomization poses a higher risk. With the measured velocities reaching up to 5 m s-1, droplets can easily reach the dentist in a few seconds. Small droplets can evaporate completely before reaching the ground and can be suspended in the air for a long time. We suggest that relative humidity in dental offices are adjusted to 50% to prevent fast evaporation while maintaining comfort in the office. This can reduce the risk of disease transmission among patients. We recommend that dentists wear a face shield and N95/FFP2/KN95 masks instead of surgical masks. We believe that this work gives health-care professionals, policy makers and engineers who design dental instruments insights into a safer dental practice.
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Affiliation(s)
- Emine Kayahan
- Center for Industrial Process Technology, Department of Chemical Engineering, KU Leuven, Agoralaan Building B, 3590, Diepenbeek, Belgium
| | - Min Wu
- Center for Industrial Process Technology, Department of Chemical Engineering, KU Leuven, Agoralaan Building B, 3590, Diepenbeek, Belgium
| | - Tom Van Gerven
- Process Engineering for Sustainable Systems, Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, B-3001 Heverlee, Belgium
| | - Leen Braeken
- Center for Industrial Process Technology, Department of Chemical Engineering, KU Leuven, Agoralaan Building B, 3590, Diepenbeek, Belgium
| | - Lambert Stijven
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, University of Leuven, Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Constantinus Politis
- OMFS IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, University of Leuven, Oral & Maxillofacial Surgery, University Hospitals Leuven, Leuven, Belgium
| | - M Enis Leblebici
- Center for Industrial Process Technology, Department of Chemical Engineering, KU Leuven, Agoralaan Building B, 3590, Diepenbeek, Belgium
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Piela K, Watson P, Donnelly R, Goulding M, Henriquez FL, MacKay W, Culshaw S. Aerosol reduction efficacy of different intra-oral suction devices during ultrasonic scaling and high-speed handpiece use. BMC Oral Health 2022; 22:388. [PMID: 36068515 PMCID: PMC9447970 DOI: 10.1186/s12903-022-02386-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 07/28/2022] [Indexed: 12/01/2022] Open
Abstract
Background The COVID-19 pandemic led to significant changes in the provision of dental services, aimed at reducing the spread of respiratory pathogens through restrictions on aerosol generating procedures (AGPs). Evaluating the risk that AGPs pose in terms of SARS-CoV-2 transmission is complex, and measuring dental aerosols is challenging. To date, few studies focus on intra-oral suction. This study sought to assess the effectiveness of commonly used intra-oral suction devices on aerosol mitigation. Methods Ultrasonic scaling and high-speed handpiece procedures were undertaken to generate aerosol particles. Multiple particle sensors were positioned near the oral cavity. Sensor data were extracted using single board computers with custom in-house Bash code. Different high-volume and low-volume suction devices, both static and dynamic, were evaluated for their efficacy in preventing particle escape during procedures. Results In all AGPs the use of any suction device tested resulted in a significant reduction in particle counts compared with no suction. Low-volume and static suction devices showed spikes in particle count demonstrating moments where particles were able to escape from the oral cavity. High-volume dynamic suction devices, however, consistently reduced the particle count to background levels, appearing to eliminate particle escape. Conclusions Dynamic high-volume suction devices that follow the path of the aerosol generating device effectively eliminate aerosol particles escaping from the oral cavity, in contrast to static devices which allow periodic escape of aerosol particles. Measuring the risk of SARS-CoV-2 transmission in a dental setting is multi-factorial; however, these data suggest that the appropriate choice of suction equipment may further reduce the risk from AGPs. Supplementary Information The online version contains supplementary material available at 10.1186/s12903-022-02386-w.
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Affiliation(s)
- Krystyna Piela
- Oral Sciences, Glasgow Dental Hospital and School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G2 3JZ, UK
| | - Paddy Watson
- Oral Sciences, Glasgow Dental Hospital and School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G2 3JZ, UK
| | - Reuben Donnelly
- Oral Sciences, Glasgow Dental Hospital and School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G2 3JZ, UK
| | | | - Fiona L Henriquez
- School of Health and Life Sciences, University of the West of Scotland, Lanarkshire Campus, Blantyre, G72 0HL, UK
| | - William MacKay
- School of Health and Life Sciences, University of the West of Scotland, Lanarkshire Campus, Blantyre, G72 0HL, UK
| | - Shauna Culshaw
- Oral Sciences, Glasgow Dental Hospital and School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G2 3JZ, UK.
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Dudding T, Sheikh S, Gregson F, Haworth J, Haworth S, Main BG, Shrimpton AJ, Hamilton FW, Ireland AJ, Maskell NA, Reid JP, Bzdek BR, Gormley M. A clinical observational analysis of aerosol emissions from dental procedures. PLoS One 2022; 17:e0265076. [PMID: 35271682 PMCID: PMC8912243 DOI: 10.1371/journal.pone.0265076] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/22/2022] [Indexed: 12/27/2022] Open
Abstract
Aerosol generating procedures (AGPs) are defined as any procedure releasing airborne particles <5 μm in size from the respiratory tract. There remains uncertainty about which dental procedures constitute AGPs. We quantified the aerosol number concentration generated during a range of periodontal, oral surgery and orthodontic procedures using an aerodynamic particle sizer, which measures aerosol number concentrations and size distribution across the 0.5-20 μm diameter size range. Measurements were conducted in an environment with a sufficiently low background to detect a patient's cough, enabling confident identification of aerosol. Phantom head control experiments for each procedure were performed under the same conditions as a comparison. Where aerosol was detected during a patient procedure, we assessed whether the size distribution could be explained by the non-salivary contaminated instrument source in the respective phantom head control procedure using a two-sided unpaired t-test (comparing the mode widths (log(σ)) and peak positions (DP,C)). The aerosol size distribution provided a robust fingerprint of aerosol emission from a source. 41 patients underwent fifteen different dental procedures. For nine procedures, no aerosol was detected above background. Where aerosol was detected, the percentage of procedure time that aerosol was observed above background ranged from 12.7% for ultrasonic scaling, to 42.9% for 3-in-1 air + water syringe. For ultrasonic scaling, 3-in-1 syringe use and surgical drilling, the aerosol size distribution matched the non-salivary contaminated instrument source, with no unexplained aerosol. High and slow speed drilling produced aerosol from patient procedures with different size distributions to those measured from the phantom head controls (mode widths log(σ)) and peaks (DP,C, p< 0.002) and, therefore, may pose a greater risk of salivary contamination. This study provides evidence for sources of aerosol generation during common dental procedures, enabling more informed evaluation of risk and appropriate mitigation strategies.
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Affiliation(s)
- Tom Dudding
- MRC Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Bristol Dental Hospital and School, University of Bristol, Bristol, United Kingdom
| | - Sadiyah Sheikh
- Bristol Aerosol Research Centre, School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Florence Gregson
- Bristol Aerosol Research Centre, School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Jennifer Haworth
- Bristol Dental Hospital and School, University of Bristol, Bristol, United Kingdom
- Royal United Hospital Bath, Combe Park, Bath, United Kingdom
| | - Simon Haworth
- MRC Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Bristol Dental Hospital and School, University of Bristol, Bristol, United Kingdom
| | - Barry G. Main
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Bristol Dental Hospital and School, University of Bristol, Bristol, United Kingdom
- Bristol Centre for Surgical Research, Population Health Sciences, Bristol Medical School, Bristol, United Kingdom
| | - Andrew J. Shrimpton
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, United Kingdom
| | - Fergus W. Hamilton
- MRC Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Infection Sciences, Southmead Hospital, North Bristol NHS Trust, Bristol, United Kingdom
| | | | - Anthony J. Ireland
- Bristol Dental Hospital and School, University of Bristol, Bristol, United Kingdom
- Royal United Hospital Bath, Combe Park, Bath, United Kingdom
| | - Nick A. Maskell
- Academic Respiratory Unit, North Bristol NHS Trust, Bristol, United Kingdom
| | - Jonathan P. Reid
- Bristol Aerosol Research Centre, School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Bryan R. Bzdek
- Bristol Aerosol Research Centre, School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Mark Gormley
- MRC Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Bristol Dental Hospital and School, University of Bristol, Bristol, United Kingdom
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Shahdad S, Hindocha A, Patel T, Cagney N, Mueller JD, Koched A, Seoudi N, Morgan C, Fleming PS, Din AR. Fallow time determination in dentistry using aerosol measurement in mechanically and non-mechanically ventilated environments. Br Dent J 2021:10.1038/s41415-021-3369-1. [PMID: 34446842 PMCID: PMC8390043 DOI: 10.1038/s41415-021-3369-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 07/19/2021] [Indexed: 12/02/2022]
Abstract
Aim To calculate fallow time (FT) required following dental aerosol generating procedures (AGPs) in both a dental hospital (mechanically ventilated) and primary care (non-mechanically ventilated). Secondary outcomes were to identify spread and persistence of aerosol in open clinics compared to closed surgeries (mechanically ventilated environment), and identify if extraoral scavenging (EOS) reduces FT and production of aerosol.Methods In vitro simulation of fast handpiece cavity preparations using a manikin was conducted in a mechanically and non-mechanically ventilated environment using Optical Particle Sizer and NanoScan at baseline, during the procedure and fallow period.Results AGPs carried out in the non-mechanically, non-ventilated environment failed to achieve baseline particle levels after one hour. In contrast, when windows were opened after AGPs, there was an immediate reduction in all particle sizes. In mechanically ventilated environments, the baseline levels of particles were very low and particle count returned to baseline within ten minutes following the AGP. There was no detectable difference between particles in mechanically ventilated open bays and closed surgeries. The effect of the EOS on reducing the particle count was greater in the non-mechanically ventilated environment; additionally, it also reduced the spikes in particle counts in mechanically ventilated environments.Conclusion High-efficiency particulate, air-filtered mechanical ventilation, along with mitigation (high-volume suction), resulted in reduction of fallow time (ten minutes). Non-ventilated rooms failed to reach baseline level even after one hour of fallow time. There was no difference in particle counts in open bays or closed surgeries in mechanically ventilated settings with an extraoral suction device reducing particulate spikes. This study confirms that AGPs are not recommended in dental surgeries where no ventilation is possible.
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Affiliation(s)
- Shakeel Shahdad
- Honorary Clinical Professor in Oral Rehabilitation & Implantology and Consultant in Restorative Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Barts Health NHS Trust, The Royal London Dental Hospital, London, UK.
| | - Annika Hindocha
- Dental Core Trainee, Restorative Dentistry and General Duties, Barts Health NHS Trust, The Royal London Dental Hospital, London, UK
| | - Tulsi Patel
- Dental Core Trainee, Restorative Dentistry and General Duties, Barts Health NHS Trust, The Royal London Dental Hospital, London, UK
| | - Neil Cagney
- Lecturer, School of Engineering and Materials Science, Faculty of Science and Engineering, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Jens-Dominik Mueller
- Reader in Computational Fluid Dynamics and Optimisation, School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Amine Koched
- Research and Analytical Application Specialist, TSI Inc, USA
| | - Noha Seoudi
- Senior Clinical Lecturer in Oral Microbiology, Centre for Oral Immunobiology and Regenerative Medicine, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AD, UK
| | - Claire Morgan
- Consultant in Restorative Dentistry, Barts Health NHS Trust, The Royal London Dental Hospital, London, UK
| | - Padhraig S Fleming
- Professor in Orthodontics and Consultant in Orthodontics, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Barts Health NHS Trust, The Royal London Dental Hospital, London, UK
| | - Ahmed Riaz Din
- Post-CCST Speciality Registrar in Orthodontics, Barts Health NHS Trust, The Royal London Dental Hospital, London, UK
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Martín-Quintero I, Cervera-Sabater A, Tapias-Perero V, Nieto-Sánchez I, de la Cruz-Pérez J. Air particulate concentration during orthodontic procedures: a pilot study. BMC Oral Health 2021; 21:361. [PMID: 34289851 PMCID: PMC8293529 DOI: 10.1186/s12903-021-01725-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/08/2021] [Indexed: 11/10/2022] Open
Abstract
Background This study evaluates the particle dispersion involved in dental procedures carried out during orthodontic treatments. Variants such as temperature and relative humidity in the dental cabinet were considered. Methods Using a particle counter, a pilot study was conducted, in which 98 consecutive recordings were made during appointments of patients undergoing orthodontic treatments. Temperature, relative humidity and particles present at the beginning (AR) and during the appointment (BR) were recorded. A control record (CR) of temperature, relative humidity and particles present was made before the start of the clinical activity. In addition to conventional statistics, differential descriptive procedures were used to analyse results, and the influence of relative humidity on particle concentration was analysed by statistical modelling with regression equations. Results The number of particles present, regardless of their size, was much higher in AR than in CR (p < .001). The same was true for relative humidity and ambient temperature. The relationship between relative humidity and particle number was determined to be exponential. Limitations of the study The limitations are associated with sample size, environmental conditions of the room and lack of discrimination among the procedures performed. Conclusions This pilot study shows that from the moment a patient enters a dental office, a large number of additional particles are generated. During treatment, the number of particles of 0.3 microns—which have a high capacity to penetrate the respiratory tract-increases. Moreover, a relationship between relative humidity and particle formation is observed. Further studies are needed.
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Affiliation(s)
- Inmaculada Martín-Quintero
- Department of Orthodontics, Universidad Alfonso X El Sabio, Madrid, Spain. .,Centro Odontológico de Innovación y Especialidades Avanzadas, Calle de Albarracín, 35, 28037, Madrid, Spain.
| | | | | | - Iván Nieto-Sánchez
- Department of Orthodontics, Universidad Alfonso X El Sabio, Madrid, Spain
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