[課題1] Nasal function in maxillectomy patients with different obturator designs, a computational fluid dynamics (CFD) study.
[Abstract]
[Objective]
The nose conditions inspired air, retaining heat and humidity from expired air. Maxillectomy for cancer often involves nasal tissues, affecting nose function and causing post-operative complaints such as nasal dryness, crusting, and frequent bleeding.[1] Although obturators improve patients' quality of life, their specific impact on nasal function hasn't been thoroughly studied. We aim to simulate the impact of maxillectomy on nasal function by assessing various factors using computational fluid dynamics (CFD), both without an obturator and with different obturator designs. This investigation will enhance our understanding of the obturator's influence on nasal function, guiding prosthodontists in designing the bulb for patients with nasal symptoms.
[Methods]
10 patients with unilateral maxillectomy defects were included. 3D airway models were created from CT images (Model-0) using MIMICS. Each defect side was 3D printed to generate the defect model, used to fabricate an obturator. The obturator was then scanned and modified to create two designs (open and closed bulb), registered to copies of Model-0 to create two additional models: Model-1&2 (Figure-1). Additionally, 10 healthy subjects were added as a control group. CFD simulations used Ansys Fluent R1-2023 and IBM-SPSS was used to run statistical tests to analyze variable differences between the four groups: Model-0,1,2 & Control.
[Results and Discussion]
On the normal sides, airflow exhibits laminar flow, whereas the defective sides display vortices of varying sizes depending on obturator design (figure-2A). Maxillectomy results in a significant increase in Tidal-volume (TV) and velocity (p<0.05), accompanied by a reduction in inspired air temperature and Relative-humidity in the nasopharynx (p<0.05). The use of obturators substantially enhances this effect (p<0.05) (figure-2B&C). Obturators significantly reduce valve velocity and tidal volume on the defective side. The obturator benefits nasal function by likely reducing inspired air velocity, TV, and enhancing aerodynamics. Tailoring these factors in obturator design aids clinicians in addressing nasal concerns. Further studies are needed to correlate with clinical symptoms and consider factors such as age, defect class, climate-variations, and radiotherapy impact.
[References]
Qian Y, Qian H, Wu Y et al. Numeric simulation of the upper airway structure and airflow dynamic characteristics after unilateral complete maxillary resection. Int J Prosthodont 2013;26(3):268-71.
[Objective]
The nose conditions inspired air, retaining heat and humidity from expired air. Maxillectomy for cancer often involves nasal tissues, affecting nose function and causing post-operative complaints such as nasal dryness, crusting, and frequent bleeding.[1] Although obturators improve patients' quality of life, their specific impact on nasal function hasn't been thoroughly studied. We aim to simulate the impact of maxillectomy on nasal function by assessing various factors using computational fluid dynamics (CFD), both without an obturator and with different obturator designs. This investigation will enhance our understanding of the obturator's influence on nasal function, guiding prosthodontists in designing the bulb for patients with nasal symptoms.
[Methods]
10 patients with unilateral maxillectomy defects were included. 3D airway models were created from CT images (Model-0) using MIMICS. Each defect side was 3D printed to generate the defect model, used to fabricate an obturator. The obturator was then scanned and modified to create two designs (open and closed bulb), registered to copies of Model-0 to create two additional models: Model-1&2 (Figure-1). Additionally, 10 healthy subjects were added as a control group. CFD simulations used Ansys Fluent R1-2023 and IBM-SPSS was used to run statistical tests to analyze variable differences between the four groups: Model-0,1,2 & Control.
[Results and Discussion]
On the normal sides, airflow exhibits laminar flow, whereas the defective sides display vortices of varying sizes depending on obturator design (figure-2A). Maxillectomy results in a significant increase in Tidal-volume (TV) and velocity (p<0.05), accompanied by a reduction in inspired air temperature and Relative-humidity in the nasopharynx (p<0.05). The use of obturators substantially enhances this effect (p<0.05) (figure-2B&C). Obturators significantly reduce valve velocity and tidal volume on the defective side. The obturator benefits nasal function by likely reducing inspired air velocity, TV, and enhancing aerodynamics. Tailoring these factors in obturator design aids clinicians in addressing nasal concerns. Further studies are needed to correlate with clinical symptoms and consider factors such as age, defect class, climate-variations, and radiotherapy impact.
[References]
Qian Y, Qian H, Wu Y et al. Numeric simulation of the upper airway structure and airflow dynamic characteristics after unilateral complete maxillary resection. Int J Prosthodont 2013;26(3):268-71.