Date of Award
Spring 2002
Document Type
Thesis - Restricted
Degree Name
Master of Science (MS)
Department
Dentistry
First Advisor
Bradley, Thomas
Second Advisor
Monaghan, Peter
Third Advisor
Toth, Jeff
Abstract
The purposes of the study are to determine whether clinical use changes the microstructure of a Ni-Ti orthodontic wire and to assess the validity of manufacturers' claims. X-ray diffraction and Vickers hardness data have been shown to corroborate the microstructural findings. Therefore, these techniques were used to examine a Ni-Ti wire for any possible structural change after a period of clinical use. Sixteen wires of 0.016 inch diameter Nitinol Classic were tested in the "as-received" conditions and then after four to six weeks of clinical use. X-ray diffraction analyses showed a 9.8% decrease in the peak height for the [110] austenite reflection of the after use wires compared to the before use wires after four to six weeks of clinical use (significant at p < 0.02). In addition, there was a 6% decrease in Vickers hardness in the after use wires compared to the before use wires after four to six weeks of clinical use (significant at p< 0.001). The decrease in peak height for the [110] austenite reflection and the decrease in Vickers hardness after four to six weeks of clinical use indicate some austenite may be irreversibly transformed to martensite during clinical use. The results of this study demonstrate that the structural properties of these wires were altered after clinical use.
Recommended Citation
Santos-Rangsuebsin, Sarah Lynn, "X-Ray Diffraction and Vickers Hardness Analyses of Nickel-Titanium Orthodontic Wires Before and After Clinical Use" (2002). Master's Theses (1922-2009) Access restricted to Marquette Campus. 5289.
https://epublications.marquette.edu/theses/5289