Keeping Casts Dry: A Comparison of Commercially Available Cast Protectors Using a Mechanized Short Arm Cast Model

Local mass transfer coefficients measured using the naphthalene sublimation technique in an acrylic cast model of the human upper respiratory tract are reported as the Sherwood numbers for the corresponding regions. A steady air flow rate of 12 L per min was used for all measurements. Values of the Sherwood number are seen to be highest in the nasal cavity and proximal nasopharynx while a minimum value occurs just downstream from the larynx. Local values of the Nusselt number obtained in the trachea and proximal nasal cavity assuming a complete heat and mass transfer analogy agree well with in-vivo physiological measurements. The mass transfer coefficients found can be incorporated into an analytical model of respiratory heat and water vapor transfer or into a model of pollutant gas uptake in the respiratory tract.

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The First Clinical Use of Augmented Reality to Treat Salivary Stones

Case Reports in Dentistry ◽

10.1155/2020/5960421 ◽

2020 ◽

Vol 2020 ◽

pp. 1-4

Author(s):

Anna Lysenko ◽

Alexandra Razumova ◽

Andrey Yaremenko ◽

Rustam Mirzakhmedov ◽

Anna Zubareva ◽

...

Keyword(s):

Augmented Reality ◽

Clinical Case ◽

Surgical Intervention ◽

Model Fitting ◽

Nasal Intubation ◽

Visualization Method ◽

X Ray ◽

Cast Model ◽

Augmented Reality Technology ◽

Preoperative Procedures

In this study, we report our first experience of applying the concretion visualization method using augmented reality technology. A clinical case of a new surgical intervention on the parotid salivary gland with the localization of salivary stone in its parenchyma is considered. During additional diagnostics, it was found that the size of the concretion exceeds 5 mm which did not allow us to use the endoscopic technologies. That was the reason for the choice of surgical intervention external access using salivary stone visualization with the help of augmented reality. The preoperative procedures included making the upper jaw cast model, fitting the model and individual mouthguard with an X-ray contrast marker and marker slot. In addition to this, computed tomography of the head and neck using a mouthguard was made. During surgery under general anesthesia with nasal intubation, the mouthguard together with the marker is installed in the patient’s mouth and the surgeon puts on the glasses to visualize the stone image in place of its localization. This method enables to visualize the salivary stone on all surgery stages no matter what type of approach is used or performing hydropreparation. That is why using the augmented reality appears promising and is to be studied further.

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Upper Lip Horizontal Line: Characteristics of a Dynamic Facial Line

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17186672 ◽

2020 ◽

Vol 17 (18) ◽

pp. 6672

Author(s):

Alexander D Vardimon ◽

Nir Shpack ◽

Atalia Wasserstein ◽

Marilena Skyllouriotou ◽

Morris Strauss ◽

...

Keyword(s):

Dental Treatment ◽

Age Groups ◽

Treatment Modalities ◽

Horizontal Line ◽

Facial Morphology ◽

Upper Lip ◽

Age Related ◽

Cast Model ◽

And Gender ◽

Gummy Smile

Background: Upper lip appearance received major attention with the introduction of diverse treatment modalities, including lip augmentation, rhinoplasty surgery, and dental treatment designed to support the upper lip. Our objectives were to define the prevalence and characteristics of the upper lip horizontal line (ULHL), which is a dynamic line appearing during a smile, in relation to gender, malocclusions, aging, and facial morphology. Methods: First, the prevalence and gender distribution of ULHL was examined from standardized en-face imaging at full smile of 643 randomly selected patients. Second, cephalometric and dental cast model analyses were made for 97 consecutive patients divided into three age groups. Results: ULHL appears in 13.8% of the population examined, and prevailed significantly more in females (78%). The prevalence of ULHL was not related to age nor to malocclusion. Patients presenting ULHL showed shorter upper lip and deeper lip sulcus. The skeletal pattern showed longer mid-face, shorter lower facial height and greater prevalence of a gummy smile. Conclusions: Female patients with short upper lip, concavity of the upper lip, and gummy smile are more likely to exhibit ULHL. The ULHL is not age-related and can be identified in children and young adults. Therefore, it should be considered when selecting diverse treatment modalities involving the upper lip.

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Three-dimensional printing technologies in the fabrication of maxillofacial prosthesis: A case report

The International Journal of Artificial Organs ◽

10.1177/0391398819887401 ◽

2019 ◽

Vol 43 (5) ◽

pp. 343-347 ◽

Cited By ~ 1

Author(s):

Pinar Cevik ◽

Mustafa Kocacikli

Keyword(s):

Case Report ◽

Three Dimensional ◽

Acrylic Resin ◽

Three Dimensional Printing ◽

Silicone Prosthesis ◽

Optical Scanner ◽

Maxillofacial Prosthesis ◽

Cast Model ◽

Healthy Side ◽

Dimensional Printing

Purpose: Patients with maxillofacial deformities always seek for aesthetic prosthesis. Recently, three-dimensional printing technologies have been used for dental treatments on such patients. Case report: A 24-year-old man reported to the Department of Prosthodontics for replacement of his missing right ear induced by a trauma. A magnet-retained auricular prosthesis was planned for the patient. Three-dimensional scanning was performed on the healthy side by using a three-dimensional optical scanner and the data were mirrored. The mirrored image was then imported to a software and a virtual model of the future prosthesis was obtained for the defect side. A three-dimensional printer was used to fabricate a negative mold for the mirrored image by using additive manufacturing. Initially, an impression of the defect side was made; then, the cast model was obtained in a dental flask. Magnets of the prosthesis were inserted to the acrylic resin framework on the cast model. Room temperature vulcanized silicone elastomer was mixed and poured into the three-dimensionally fabricated mold. Then, the flask was placed over the negative mold firmly. After polymerization of the silicone, the auricular prosthesis was delivered to the patient and the patient was instructed to clean the prosthesis daily. Conclusions: Three-dimensional printing technology was used for the fabrication of the patient’s missing ear. This method eliminated the conventional laboratory steps and reduced the number of stages of the fabrication of a silicone prosthesis. The negative mold of the defect side allowed us a direct fabrication of the silicone prosthesis without a need for waxing or flasking procedures.

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EXPERIMENTAL STUDIES ON THE THRESHOLD OF VEHICLE INSTABILITY IN FLOODWATERS

Jurnal Teknologi ◽

10.11113/jt.v80.11198 ◽

2018 ◽

Vol 80 (5) ◽

Cited By ~ 2

Author(s):

Syed Muzzamil Hussain Shah ◽

Zahiraniza Mustaffa ◽

Khamaruzaman Wan Yusof

Keyword(s):

Experimental Studies ◽

Orientation Angle ◽

High Water ◽

Road Surface ◽

The Other ◽

Low Flow ◽

Flood Risks ◽

Die Cast ◽

Cast Model ◽

Water Depths

Flood risks concerned to vehicle’s instability have become more conspicuous and it is thus necessary to understand the behaviour of vehicles exposed to floodwaters. Therefore, this paper aims at investigating the thresholds of vehicle instability in floodwaters at different orientations. A stationary die-cast model vehicle (1:24) was used with the condition of rear tires being locked only, positioned at different orientation angles on a flat road surface in the partially submerged zone. Measurements were taken including the approaching velocities and water depths, through which the instability was computed. The study concludes that a partially submerged vehicle becomes instable at high water depths and low flow velocities and vice versa. Further, the vehicle was observed to be most stable when positioned at orientation angle of 0°/360°, with the limiting depth × velocity (D*V) value of 0.0168 m2/s. On the other hand, it was noted to be least stable when positioned at the orientation angle of 90° and 270°, with the limiting (D*V) value of 0.0144 m2/s. The outcomes from this study were later translated into guidelines.

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