FIGURE 2.

Illustration of the study methodology. Three registration methods (R1, landmark-based registration on the posterior teeth; R2, landmark-based registration on the palate; R3, registration on the palate using regions of interest) were performed by 2 observers (Observer 1 and Observer 2). Observer 1 performed the registrations twice (1st, first measurement; 2nd, second measurement). Red arrows denote comparisons between methods of registration (R1 × R2, R1 × R3 and R2 × R3) performed by observer 1 (1st and 2nd) and by observer 2. Intraobserver and interobserver comparisons were performed for each method of registration (R1, R2 and R3). Orange arrows denote intraobserver comparisons between first and second measurements (1st × 2nd). Green arrows denote interobserver comparisons (Observer 1 × Observer 2)