STABILITY OF HAND VERSUS ELECTRICALLY DRIVEN TEMPORARY ANCHORAGE DEVICES
STABILITY OF HAND VERSUS ELECTRICALLY DRIVEN TEMPORARY ANCHORAGE DEVICES

Author: Lauren Pinkus

Publisher:

Published: 2021

Total Pages: 53

ISBN-13:

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Objectives: Temporary anchorage devices (TADs) provide skeletal anchorage for orthodontic tooth movement. TAD stability is defined as device retention during treatment. Insertion of TADs can either be hand-driven, relying on tactile sensation, or electric-driven, with established presets with specific torque and speed. Although device manufacturers claim that electric-driven insertion provides greater stability, this is currently unsubstantiated. The aim of this study was to compare stability, as measured by resistance to deflection, and insertion time of TADs placed using these two methods.Methods: Twenty TADs (Rocky Mountain Orthodontics; 1.6mm x 8mm) were inserted into synthetic bone blocks mimicking palatal bone: 20 PCF with a 1mm cortical plate of 40 PCF (Sawbones USA). TADs were inserted by two methods, hand-driven (n=10) and electric-driven (n=10; at 10 N•cm, 15 RPM) perpendicular to the surface of the bone blocks. All TADs were subjected to a tangential force using an Instron machine until their deflection measured 2.5mm. The force versus displacement over time was recorded and the slope was calculated to determine resistance to deflection. The insertion time was recorded for each TAD. Results: Hand-driven TADs had a mean resistance to deflection (76.30 N/mm ± 11.70), yield point (43.61 N ± 4.34), and insertion time (28.929 s ± 3.47). Electric-driven TADs had a mean resistance to deflection (79.34N/mm ± 17.95), yield point (40.81N ± 4.58), and insertion time (77.642 s ± 7.21). An independent samples t-test revealed no significant difference in TAD resistance to deflection (p=0.658) or yield point (p=0.177) between the two groups. Hand insertion time was on average 2.68 times faster (p=0.000) than electric insertion time. Individual measurements had small standard deviations, indicating reliability to the experimental approach. Conclusion: There are no significant differences in stability between hand-driven and electric-driven TADs when studied by this method. These results indicate that electric drivers may require more operating time and do not necessarily provide more TAD stability.

Cal/OSHA Pocket Guide for the Construction Industry
Cal/OSHA Pocket Guide for the Construction Industry

Author:

Publisher:

Published: 2015-01-05

Total Pages:

ISBN-13: 9781622701070

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The Cal/OSHA Pocket Guide for the Construction Industry is a handy guide for workers, employers, supervisors, and safety personnel. This latest 2011 edition is a quick field reference that summarizes selected safety standards from the California Code of Regulations. The major subject headings are alphabetized and cross-referenced within the text, and it has a detailed index. Spiral bound, 8.5 x 5.5"

Temporary Skeletal Anchorage Devices
Temporary Skeletal Anchorage Devices

Author: Ki Beom Kim

Publisher: Springer

Published: 2014-07-11

Total Pages: 238

ISBN-13: 3642550525

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Anchorage control is one of the most challenging tasks in orthodontic treatment. Many different types of appliance are used to control anchorage, but an excellent outcome may be difficult to achieve owing to either poor mechanics or inadequate patient compliance. Recently, temporary skeletal anchorage devices (TSADs) have become popular in orthodontics. Some orthodontic movements that are now possible using TSADs were previously considered almost impossible with traditional orthodontic appliances. Several different types of TSAD are currently available, and in choosing between them orthodontists are obliged to rely on the information provided by manufacturers, which is often not based on scientific evidence. This book therefore presents the various design characteristics of TSADs and provides up-to-date scientific evidence to assist orthodontists in selecting the best TSADs for their patients.

Backpacker
Backpacker

Author:

Publisher:

Published: 2001-03

Total Pages: 206

ISBN-13:

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Backpacker brings the outdoors straight to the reader's doorstep, inspiring and enabling them to go more places and enjoy nature more often. The authority on active adventure, Backpacker is the world's first GPS-enabled magazine, and the only magazine whose editors personally test the hiking trails, camping gear, and survival tips they publish. Backpacker's Editors' Choice Awards, an industry honor recognizing design, feature and product innovation, has become the gold standard against which all other outdoor-industry awards are measured.

Construction Business Management
Construction Business Management

Author: S. Peter Volpe

Publisher: John Wiley & Sons

Published: 1992-04-16

Total Pages: 254

ISBN-13: 9780471536369

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Provides a wide insight into the construction business, showing the reader how a contractor organizes a construction company and controls his work. Offers a practical and direct approach and describes how a business starts up, how it's organized and how it's financed. Also covers estimating, cost keeping systems, labor relations, equipment, safety, and insurance. Augmented with numerous case histories, forms and sample agreements to keep a job on schedule and within budget.