The objective of this study was to investigate the initial effects of a tongue crib on tongue movements during deglutition by using real time balanced turbo field echo (B-TFE) Cine-MR imaging. A total of 21 patients were evaluated in this study. The open-bite group (OBG) consisted of 11 patients (seven girls, four boys) who had a mean age of 11.09 +/- 2.02 years and a mean overbite of -5.14 +/- 1.83 mm. These patients were evaluated initially (T1) and while wearing a tongue crib (T2). A total of 10 patients (five girls, five boys) with a mean age of 14.5 +/- 2.6 years and with a mean overbite of 1.6 +/- 0.5 mm served as controls (CG), and only initial records were obtained from these patients. T2 was compared with T1 and CG. T1 was also compared with CG. We evaluated deglutition during three stages matching oral (1), pharyngeal (2), and esophageal (3) stages. Our results indicated that the tongue's tip positioned more posteriorly when the crib was in place (T2) compared with both T1 and CG; the anterior portion of the tongue's dorsum was at a lower position in T2 compared with both T1 and CG at stage 3; the midportion of the tongue's dorsum was at a lower position in T2 than in T1 and CG at stages 1 and 2. To compensate for the posterior position of the tongue's tip (caused by the tongue crib), adaptive changes occurred in the anterior and midportions of the dorsum of the tongue.