Possibility of reconstruction of dental plaster cast from 3D digital study models

Table 2 Results of the paired t -test of the null hypothesis and results of F-test of the null hypothesis

		Axis	Mean [mm]	95% confidence interval		P value	Value of the test statistic	95% confidence interval		P value
PM-RR	for 3-3	x	−0.17	−0.35	0.01	0.06	1.61	0.40	6.48	0.49
	for 3-6	y	−0.05	−0.18	0.09	0.47	3.08	0.77	12.4	0.11
	for 3	z	−0.03	−0.16	0.09	0.55	0.42	0.11	1.71	0.22
	for 3-1	mixed	0.04	−0.07	0.15	0.45	0.52	0.13	2.08	0.34

This table shows the results of the paired t-test. 3–3 means intercanine distance, x-plane, 3–6 means y-plane, 3 means clinical hight of crown of canine, 3–1 states for mixed plane. The null hypothesis states that there are no differences between the measurements on the plaster models (PM) and RepRap 3D printed copies (RR). And the samples were randomly selected from a normal distribution with mean 0 and unknown variance. The alternative hypothesis is that that the mean is not 0. The second part of the table depicts the results of the F-test. The null hypothesis states that the differences of the repeated measurements on the plaster models and the difference of the repeated measurements on the RepRap 3D printed copies are from a normal distributions with the same variance. The alternative hypothesis states that they are from a normal distributions with different variances.

ISSN: 1475-925X