Influence of Preadjusted Bracket Shape and Positioning Reference on Angulation of Upper Central Incisor

2016 ◽  
Vol 17 (10) ◽  
pp. 786-790
Author(s):  
Osmar A Cuoghi ◽  
Francielle Topolski ◽  
Mauricio A de O Accorsi ◽  
Hugo J Trevisi ◽  
Ricardo Moresca

ABSTRACT Aim To verify the influence of different bracket shapes and placement references according to Andrews and MBT systems on the expression of angulation in upper central incisors (UCI). Materials and methods Bracket positioning and mesiodistal dental movement simulations were performed and the angulations produced in the dental crown were evaluated, based on computed tomography scan images of 30 UCI and AutoCAD software analysis. Rectangular (Andrews) and rhomboid (MBT) brackets were placed according to the references recommended by Andrews and MBT systems – long axis of the clinical crown (LACC) and incisal edge (IE) respectively. Results Data showed that the use of LACC as reference for bracket positioning produced 5° and 4° UCI angulations in Andrews and MBT brackets respectively. The use of IE produced a 1.2° mean angulation in UCI for both brackets. Conclusion When the LACC was used as reference for bracket positioning, the UCI crown angulation corresponded to the angulation built into the brackets, regardless of shape, while the use of IE resulted in natural crown angulation, regardless of bracket shape. Clinical significance This research contributes to guide the orthodontist in relation to the different treatment techniques based on the use of preadjusted brackets. How to cite this article Topolski F, de O Accorsi MA, Trevisi HJ, Cuoghi OA, Moresca R. Influence of Preadjusted Bracket Shape and Positioning Reference on Angulation of Upper Central Incisor. J Contemp Dent Pract 2016;17(10):786-790.

2009 ◽  
Vol 75 (11) ◽  
pp. 1081-1083 ◽  
Author(s):  
Daniela Molena ◽  
Nicole Burr ◽  
Andrea Zucchiatti ◽  
Erik Lovria ◽  
Mark L. Gestring ◽  
...  

With the increased use of chest computed tomography (CT) scan in the initial evaluation of major trauma, findings that were not seen on a chest radiograph (CXR) are increasingly identified. Pneumomediastinum (PM) seen on CXR in blunt trauma patients is considered worrisome for airway and/or esophageal injury. The purpose of this study was to determine the incidence and clinical significance of PM found on CT in blunt trauma patients. Blunt trauma patients admitted to a single Regional Trauma Center over a 2-year period were identified. Records were reviewed for demographics, mechanism, diagnostic evaluations, injuries, and outcome. A total of 2052 patients met study criteria. Fifty-five (2.7%) had PM; 49 patients (89%) had PM identified on CT alone, whereas six patients (11%) had it identified on both CXR and CT. There was no significant difference in gender or age between the two groups. Associated injuries were similar between groups. No patients had tracheobronchial or esophageal injuries. In this study, PM seen on CT was found to have little clinical significance other than as a marker for severe blunt trauma. No patients with airway or esophageal injuries were seen in any of the PM patients.


2021 ◽  
pp. 014556132110346
Author(s):  
Konstantinos Garefis ◽  
Konstantinos Tarazis ◽  
Konstantinos Gkiouzelis ◽  
Anastasia Kipriotou ◽  
Iordanis Konstantinidis ◽  
...  

A tracheal diverticulum is a type of paratracheal air cyst and is usually an incidental finding after a computed tomography scan of the neck and thorax. With an incidence between 1% and 4% in adults, tracheal diverticula are rare entities that can be symptomatic in certain cases. We present a case of a COVID-19 positive patient who presented to our hospital and was diagnosed with multiple tracheal diverticula during his hospitalization.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Binghua Zhu ◽  
Jing Tang ◽  
Rong Fang ◽  
Xuejie Fei ◽  
Qing Wang ◽  
...  

Abstract Background We diagnosed a clinical case of pulmonary infection involving Mycobacterium tuberculosis and Tropheryma whipplei in a patient with acute respiratory distress syndrome. The diagnosis was assisted by metagenomic next-generation sequencing of bronchoalveolar lavage fluid. Case presentation A 44-year-old Han Chinese inmate was transferred to the emergency department because of dry cough, chest tightness, and shortness of breath. The patient’s body temperature rose to 39.3 °C following empirical cephalosporin treatment for 1 week. The blood CD4+/CD8+ ratio was 0.7, suggesting immunodeficiency. Routine microbiological tests were performed, and tuberculosis interferon gamma release assays were positive. Mycobacterium tuberculosis polymerase chain reaction was also positive. Chest computed tomography scan revealed miliary nodules and ground-glass opacifications, which were in accordance with tuberculosis. To fully examine the etiology, we performed routine laboratory tests and metagenomic sequencing, the results of which indicated the presence of Mycobacterium tuberculosis and Tropheryma whipplei. We administered anti-tuberculosis regimen in combination with trimethoprim/sulfamethoxazole. The patient recovered, with chest computed tomography scan showing absorption of lesions. Conclusions Compared with traditional diagnostic methods such as culture and serology, metagenomic next-generation sequencing has the advantage of detecting a wide array of microorganisms in a single test and therefore can be used for clinical diagnosis of rare pathogens and microbial coinfections. It is particularly useful for immunocompromised patients as they are more prone to infection by opportunistic microorganisms.


Author(s):  
Digamber Singh

The human respiratory tract has a complex airflow pattern. If any obstruction is present in the airways, it will change the airflow pattern and deposit particles inside the airways. This is the concern of breath quality (inspired air), and it is decreasing due to the unplanned production of material goods. This is a primary cause of respiratory illness (asthma, cancer, etc.). Therefore, it is important to identify the flow characteristics in the human airways and airways with a glomus tumour with particle deposition. A numerical diagnosis is presented with an asymmetric unsteady-state light breathing condition (10 l/min). An in vitro human respiratory tract model has been reconstructed using computed tomography scan techniques and an artificial glomus tumour developed 2 cm above a carina on the posterior wall of the trachea. The transient flow characteristics are numerically simulated with a realizable (low Reynolds number) k–ɛ turbulence model. The flow disturbance is captured around the tumour, which influenced the upstream and downstream of the flow. The flow velocity pattern, wall shear stress and probable area of inflammation (hotspot) due to suspended particle deposition are determined, which may assist doctors more effectively in aerosol therapy and prosthetics of human airways illness.


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