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1.
J Emerg Nurs ; 47(5): 721-732, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303530

RESUMO

OBJECTIVE: Emergency departments face unforeseen surges in patients classified as low acuity during pandemics such as the coronavirus disease pandemic. Streamlining patient flow using telemedicine in an alternative care area can reduce crowding and promote physical distancing between patients and clinicians, thus limiting personal protective equipment use. This quality improvement project describes critical elements and processes in the operationalization of a telemedicine-enabled drive-through and walk-in garage care system to improve ED throughput and conserve personal protective equipment during 3 coronavirus disease surges in 2020. METHODS: Standardized workflows were established for the operationalization of the telemedicine-enabled drive-through and walk-in garage care system for patients presenting with respiratory illness as quality improvement during disaster. Statistical control charts present interrupted time series data on the ED length of stay and personal protective equipment use in the week before and after deployment in March, July, and November 2020. RESULTS: Physical space, technology infrastructure, equipment, and staff workflows were critical to the operationalization of the telemedicine-enabled drive-through and walk-in garage care system. On average, the ED length of stay decreased 17%, from 4.24 hours during the week before opening to 3.54 hours during the telemedicine-enabled drive-through and walk-in garage care system operation. There was an estimated 25% to 41% reduction in personal protective equipment use during this time. CONCLUSION: Lessons learned from this telemedicine-enabled alternative care area implementation can be used for disaster preparedness and management in the ED setting to reduce crowding, improve throughput, and conserve personal protective equipment during a pandemic.


Assuntos
COVID-19/diagnóstico , Serviço Hospitalar de Emergência/organização & administração , Telemedicina/métodos , Triagem/organização & administração , COVID-19/epidemiologia , Planejamento em Desastres , Humanos , Pandemias/prevenção & controle , Equipamento de Proteção Individual
2.
Eur J Orthod ; 35(6): 719-29, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21750240

RESUMO

Edgewise orthodontic treatment utilizes a force couple in order to achieve labial-lingual tooth angulation. Two self-ligating brackets (Damon Q and Speed) were examined across a range of clinically relevant torques in order to assess the loading and unloading curves and bracket deformation. A previously developed torquing and load measurement system was utilized to rotate a 0.199 × 0.25 in stainless steel wire in a fixed bracket slot to the following angles: 16, 20, 24, 28, 32, and 40 degrees. The torque on the bracket was measured during both wire loading and unloading cycles. The torque play for the Damon brackets was determined to increase by less than 0.4 degrees when torqued to 70 Nmm, whereas the increase for the Speed brackets was 2.1 degrees at the same torque magnitude. The deformation curves for the Damon and Speed brackets were found to be different for loading and unloading. Speed brackets were found to start to plastically deform when torqued to 24 degrees (26 Nmm of torque), while Damon brackets did not plastically deform until 28 degrees (38 Nmm of torque). Damon brackets were found not to plastically deform as easily and to have a smaller increase in torque play than Speed brackets. Both the Damon and the Speed brackets demonstrated minimal effect of plastic deformation and torque play at maximum angles of twist less than 20 degrees. Torque measured in the brackets was different for loading and unloading.


Assuntos
Análise do Estresse Dentário/métodos , Desenho de Aparelho Ortodôntico , Braquetes Ortodônticos , Humanos , Plásticos , Aço Inoxidável , Torque
3.
J Orthod ; 39(1): 25-33, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22433324

RESUMO

OBJECTIVE: To measure the plastic deformation of three different self-ligated brackets as a result of third order torque by analysing slot dimensions and determine its impact on torque play. METHODS: Three different self-ligating orthodontic brackets (0·022-inch slot) were investigated: Damon Q®, In-Ovation R®, and Speed® (30 per group). A digital SLR camera coupled to a microscope was used to capture images of the slot profile of each bracket before and after torquing. Each bracket was torqued to 63° in the same manner using a 0·019×0·025-inch SS wire. RESULTS: The mean change in slot height as measured at the top of the slot was 0·013 mm (SD 0·020), 0·007 mm (SD 0·010) and 0·070 mm (SD 0·03) for Damon Q®, In-Ovation R® and Speed®, respectively. Slot taper increased 0·75° (SD 0·96), 0·41° (SD 1·05) and 9·30° (SD 4·24), respectively. Increase in torque play was calculated to be 0·9, 0·6 and 7·7° respectively, as calculated using the novel formula presented in this study. CONCLUSIONS: Damon Q® and In-Ovation R® maintain high levels of linearity in the shape of the slot walls and experience small, but significant amounts of plastic deformation that are physically insignificant. Speed® demonstrates the most plastic deformation with visually identifiable warping in the bracket slot.


Assuntos
Análise do Estresse Dentário , Desenho de Aparelho Ortodôntico , Braquetes Ortodônticos , Fotografia Dentária/instrumentação , Torção Mecânica
4.
Am J Orthod Dentofacial Orthop ; 140(3): 326-39, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21889077

RESUMO

INTRODUCTION: Control of root torque is often achieved by introducing a twist in a rectangular archwire. The purpose of this study was to investigate third-order torque on different types of self-ligated brackets by analyzing the bracket's elastic and plastic deformations in conjunction with the expressed torque at varying angles of twist. METHODS: An orthodontic bracket was mounted to a load cell that measured forces and moments in all directions. The wire was twisted in the bracket via a stepper motor, controlled by custom software. Overhead images were taken by a camera through a microscope and processed by using optical correlation to measure deformation. RESULTS: At the maximum torquing angle of 63° with 0.019 × 0.025-in stainless steel wire, the total elastic and plastic deformation values were 0.063, 0.033, and 0.137 mm for Damon Q (Ormco, Orange, Calif), In-Ovation R (GAC, Bohemia, NY), and Speed (Strite Industries, Cambridge, Ontario, Canada), respectively. The total plastic deformation values were 0.015, 0.006, and 0.086 mm, respectively, measured at 0° of unloading. CONCLUSIONS: In-Ovation R had the least deformation due to torquing of the 3 investigated bracket types. Damon Q and Speed on average had approximately 2.5 and 14 times greater maximum plastic deformation, respectively, than did In-Ovation R.


Assuntos
Análise do Estresse Dentário , Desenho de Aparelho Ortodôntico , Braquetes Ortodônticos , Ligas Dentárias , Elasticidade , Modelos Lineares , Aço Inoxidável , Estatísticas não Paramétricas , Estresse Mecânico , Torque
5.
Am J Orthod Dentofacial Orthop ; 139(1): e31-44, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21195255

RESUMO

INTRODUCTION: Axial rotation of orthodontic wire produces buccal or lingual root movement and is often referred to as third-order movement or "torque expression." The objective of this study was to quantify torque expression in 3 self-ligation bracket systems (Damon Q, Ormco, Orange, Calif; In-Ovation R, GAC, Bohemia, NY; and Speed, Strite Industries, Cambridge, Ontario, Canada) during loading and unloading. METHODS: A stepper motor was used to rotate a wire in a fixed bracket slot from -15° to 63° in 3° increments, and then back to -15°. The bracket was mounted on top of a load cell that measured forces and moments in all directions. RESULTS: Damon's and In-Ovation's maximum average torque values at 63° were 105 and 113 Nmm, respectively. Many Speed brackets experienced premature loss of torque between 48° and 63°, and the average maximum was 82 Nmm at 54°. The torque plays for Damon, In-Ovation, and Speed were 11.3°, 11.9°, and 10.8°, respectively. CONCLUSIONS: Generally, In-Ovation expressed the most torque at a given angle of twist, followed by Damon and then Speed. However, there was no significant difference between brackets below 34 Nmm of torque. From a clinical perspective, the torque plays between brackets were virtually indistinguishable.


Assuntos
Braquetes Ortodônticos , Fios Ortodônticos , Ligas Dentárias/química , Humanos , Teste de Materiais , Movimento , Desenho de Aparelho Ortodôntico , Rotação , Aço Inoxidável/química , Estresse Mecânico , Propriedades de Superfície , Técnicas de Movimentação Dentária/instrumentação , Torque
6.
J Dent Biomech ; 2010: 781321, 2010 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-20981299

RESUMO

In all manufacturing processes there are tolerances; however, orthodontic bracket manufacturers seldom state the slot dimensional tolerances. This experiment develops a novel method of analyzing slot profile dimensions using photographs of the slot. Five points are selected along each wall, and lines are fitted to define a trapezoidal slot shape. This investigation measures slot height at the slot's top and bottom, angles between walls, slot taper, and the linearity of each wall. Slot dimensions for 30 upper right central incisor self-ligating stainless steel brackets from three manufacturers were evaluated. Speed brackets have a slot height 2% smaller than the nominal 0.559 mm size and have a slightly convergent taper. In-Ovation brackets have a divergent taper at an average angle of 1.47 degrees. In-Ovation is closest to the nominal value of slot height at the slot base and has the smallest manufacturing tolerances. Damon Q brackets are the most rectangular in shape, with nearly 90-degree corners between the slot bottom and walls. Damon slot height is on average 3% oversized.

7.
Angle Orthod ; 80(5): 884-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20578859

RESUMO

OBJECTIVE: The force moment providing rotation of the tooth around the x-axis (buccal-lingual) is referred to as torque expression in orthodontic literature. Many factors affect torque expression, including the wire material characteristics. This investigation aims to provide an experimental study into and comparison of the torque expression between wire types. MATERIALS AND METHODS: With a worm-gear-driven torquing apparatus, wire was torqued while a bracket mounted on a six-axis load cell was engaged. Three 0.019 x 0.0195 inch wire (stainless steel, titanium molybdenum alloy [TMA], copper nickel titanium [CuNiTi]), and three 0.022 inch slot bracket combinations (Damon 3MX, In-Ovation-R, SPEED) were compared. RESULTS: At low twist angles (<12 degrees), the differences in torque expression between wires were not statistically significant. At twist angles over 24 degrees, stainless steel wire yielded 1.5 to 2 times the torque expression of TMA and 2.5 to 3 times that of nickel titanium (NiTi). At high angles of torsion (over 40 degrees) with a stiff wire material, loss of linear torque expression sometimes occurred. CONCLUSIONS: Stainless steel has the largest torque expression, followed by TMA and then NiTi.


Assuntos
Ligas/química , Cobre/química , Ligas Dentárias/química , Níquel/química , Braquetes Ortodônticos , Fios Ortodônticos , Aço Inoxidável/química , Titânio/química , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Desenho de Aparelho Ortodôntico , Rotação , Estresse Mecânico , Propriedades de Superfície , Temperatura , Torque , Torção Mecânica , Transdutores
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