{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:00:55Z","timestamp":1787029255338,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,10,13]],"date-time":"2022-10-13T00:00:00Z","timestamp":1665619200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Victorian Government Innovation Connections","award":["ICG001894"],"award-info":[{"award-number":["ICG001894"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>Pulmonary drug delivery aims to deliver particles deep into the lungs, bypassing the mouth\u2013throat airway geometry. However, micron particles under high flow rates are susceptible to inertial impaction on anatomical sites that serve as a defense system to filter and prevent foreign particles from entering the lungs. The aim of this study was to understand particle aerodynamics and its possible deposition in the mouth\u2013throat airway that inhibits pulmonary drug delivery. In this study, we present an analysis of the aerodynamics of inhaled particles inside a patient-specific mouth\u2013throat model generated from MRI scans. Computational Fluid Dynamics with a Discrete Phase Model for tracking particles was used to characterize the airflow patterns for a constant inhalation flow rate of 30 L\/min. Monodisperse particles with diameters of 7 \u03bcm to 26 \u03bcm were introduced to the domain within a 3 cm-diameter sphere in front of the oral cavity. The main outcomes of this study showed that the time taken for particle deposition to occur was 0.5 s; a narrow stream of particles (medially and superiorly) were transported by the flow field; larger particles &gt; 20 \u03bcm deposited onto the oropharnyx, while smaller particles &lt; 12 \u03bcm were more disperse throughout the oral cavity and navigated the curved geometry and laryngeal jet to escape through the tracheal outlet. It was concluded that at a flow rate of 30 L\/min the particle diameters depositing on the larynx and trachea in this specific patient model are likely to be in the range of 7 \u03bcm to 16 \u03bcm. Particles larger than 16 \u03bcm primarily deposited on the oropharynx.<\/jats:p>","DOI":"10.3390\/ph15101259","type":"journal-article","created":{"date-parts":[[2022,10,13]],"date-time":"2022-10-13T22:21:11Z","timestamp":1665699671000},"page":"1259","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Flow Patterns and Particle Residence Times in the Oral Cavity during Inhaled Drug Delivery"],"prefix":"10.3390","volume":"15","author":[{"given":"Brenda","family":"Vara Almirall","sequence":"first","affiliation":[{"name":"Mechanical & Automotive Engineering, School of Engineering, Royal Melbourne Institute of Technology University, Bundoora, VIC 3083, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0476-0237","authenticated-orcid":false,"given":"Kiao","family":"Inthavong","sequence":"additional","affiliation":[{"name":"Mechanical & Automotive Engineering, School of Engineering, Royal Melbourne Institute of Technology University, Bundoora, VIC 3083, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kimberley","family":"Bradshaw","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Head and Neck Surgery, Westmead Hospital, Westmead, NSW 2145, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7719-1832","authenticated-orcid":false,"given":"Narinder","family":"Singh","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Head and Neck Surgery, Westmead Hospital, Westmead, NSW 2145, Australia"},{"name":"Sydney Medical School, Faculty of Medicine & Health, The University of Sydney, Sydney, NSW 2006, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7577-0267","authenticated-orcid":false,"given":"Aaron","family":"Johnson","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology-Head and Neck Surgery & Department of Rehabilitation Medicine, Grossman School of Medicine, New York University, New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pippa","family":"Storey","sequence":"additional","affiliation":[{"name":"Department of Radiology, Grossman School of Medicine, New York University, New York, NY 10016, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9404-2417","authenticated-orcid":false,"given":"Hana","family":"Salati","sequence":"additional","affiliation":[{"name":"Mechanical & Automotive Engineering, School of Engineering, Royal Melbourne Institute of Technology University, Bundoora, VIC 3083, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1016\/0021-8502(82)90020-9","article-title":"Measurements of the total and regional deposition of inhaled particles in the human respiratory tract","volume":"13","author":"Emmett","year":"1982","journal-title":"J. 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