Date of Award

5-1998

Degree Type

Master's Essay - Restricted

Degree Name

Master of Science (MS)

Department

Dentistry

First Advisor

Virendra Dhuru

Second Advisor

Donald Ferguson

Third Advisor

Russell Kittleson

Abstract

The aim of this study was to compare the mechanical properties of latex and non-latex elastics. Four brands of elastics were used with three latex and three nonlatex samples. All samples were 1/4 "4 oz. elastics. Two sets of tests were conducted. In the first set, fracture load and extension at fracture were measured using an Instron Universal testing machine. In the second set of tests, the maximum load, 2 minute load, load relaxation and relaxation energy were measured with the Instron as well. Specimens were tested both dry and wet in a simulated oral environment. Elastics were tested with and without pre-stretching. The pre-stretched samples were held at 25 mm for a duration of 5 hours before testing on the Instron. It was found that there is a significant difference in mechanical properties between latex and non-latex orthodontic elastics. Of the three non-latex brands tested, those from American Orthodontics and GAC International performed adequately for use in the orthodontic office. American and GAC non-latex elastics behave similarly in most respects to all latex brands studied. Relaxation was slightly higher, but would not impact the clinical situation greatly (0.02 kg for American and GAC non-latex elastics and 0.01 kg for all latex brands studied). The mean fracture load delivered was significantly lower for the American and GAC non-latex elastics which would require more ounces of force to deliver the same effect as latex elastics (American latex: 3.48 kg, American non-latex: 2.37 kg, GAC latex: 3.60 kg, GAC non-latex: 2.60 kg, Masel non-latex: 1.48 kg, Unitek latex: 3.87). The fracture extension of Masel non-latex elastics prohibit their use intra-orally for intra-arch mechanics (Masel: 58.3 7 mm).

Comments

A Thesis Submitted to the Faculty of the graduate School, Marquette University, in Partial Fulfillment of the requirements for the degree of Master of Science Milwaukee, Wisconsin.

Download

Share

COinS