Two examiners were involved in the evaluations, and inter-examiner reliability of 0.932 was obtained.

All the data were tabulated and statistically analyzed using IBM SPSS Statistics software version 22. The t test was used to compare intraoral and master cast horizontal distances as well as sub-groups of the open and close impression tray techniques. Where data are not normally distributed, Wilcoxon signed test was used for numerical dependent data and paired data; Mann-Whitney U test was used for independent numerical groups. Chi-square test was used for the association between categorical variables. The p value was set at p ≤ 0.05 and regarded as statistically significant.