Orthodontics and Orthodontology Commons^™

The Effect Of Modifications To Intermaxillary Orthodontic Elastics On Force Levels And Degradation Over Time, Steven Dent

Electronic Thesis and Dissertation Repository

Introduction: Orthodontic elastics are frequently used in orthodontic treatment but there is little research into how to modify their prescription to improve their performance. The aim of this study was to evaluate potential wear modifications to a standard Class II intermaxillary elastic prescription on force levels and force degradation over time.

Methods: For this in vitro study, Ormco (OR) and American Orthodontic (AO) latex elastics had five modifications made to a standard 1/4”/4.5oz control elastic (Group 1). These included an increase of force level by one unit to 6 or 6.5oz (Group 2); a decrease in lumen size to 3/16” …

Torque Expression Of Active And Passive Self-Ligating Orthodontic Brackets With Different Stainless Steel Wire Sizes, Jennifer L. Boogaards

Electronic Thesis and Dissertation Repository

This investigation aimed to compare engagement angles and torquing moments generated by stainless steel (SS) wires in three active self-ligating (ASL), one passive self-ligating (PSL), and a conventional twin orthodontic bracket system control. Brackets were tested in simulations of buccal and palatal root torque using four sizes of SS wires (16x22, 17x25, 19x25, 20x20 mil). A custom 3D printed testing apparatus was developed to measure torque. After initial engagement within bracket slots, torquing moments increased with progressive rotation of brackets around wires. In general, the PSL and conventionally ligated systems generated significantly larger torquing moments than ASL systems, especially with …