STATISTICAL ANALYSIS
To determine the statistical significance of the inter- lot variances between manufacturers in As and Af tem- peratures for each type of wire sampled, the F test of equality of variances was conducted using the statistical software R (version 2.11.1; R Development Core Team, GNU Corporation, Auckland, New Zealand). The F test was also used to compare the variances of the force ex- erted by each wire on unloading, at 2 mm of deflection during the 3-point bend test.
One-sample t tests were performed to compare the mean Af temperatures to those reported by the manufac- turer. All statistical analyses were performed at the P #0.05 level of significance.