Document Type


Date of Degree

Spring 2016

Degree Name

MS (Master of Science)

Degree In


First Advisor

Robert N. Staley


Orthodontic materials are evolving. The aim was to find out how this affects treatment outcomes. Brackets are getting smaller and smaller in the name of esthetics and patient comfort. The aim of this study was to find out if intrabracket width (the horizontal distance between bracket tie wings) had any effect on maxillary anterior root torque. We also aimed to find out if three common orthodontic archwires were capable of delivering the torque necessary to achieve ideal root torque.

A machine was developed to simulate lingual root torque of an upper central incisor. This is the first test of its kind, presumably because intrabracket width is thought to have no effect on torque. It was found that all three archwire groups were capable of delivering the torque needed to accomplish treatment goals. Torque was found in this experiment to be expressed differently in wide and narrow brackets. The wider bracket required less torque in the archwire to produce the same force compared to that in a narrow bracket. The implications of this finding are that orthodontists may need to adjust the torque being placed in archwires based upon the intrabracket width of the brackets they are using.

Public Abstract

We aimed to find out if the material of the wire in braces made any difference in treatment as it relates to the angulation of the front teeth. We also wanted to find out if the width of the bracket had any effect on the angulation of the front teeth. A machine was developed to measure any differences in the angle when a wire was inserted into the bracket and a load applied.

We found that when a load was applied to a wide bracket there was a difference between the angle produced when the same load was applied to a narrow bracket. We also found that the material of the wire had a different angle with the same applied load. All wires tested showed that the angles we need to create in front teeth during orthodontic treatment are achievable with all types of wires tested. It also showed that perhaps the forces we have typically used to angle front teeth may be greater than that needed to get the job done.




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Copyright 2016 Terry Jay Schmitt