Subjects and Methods: The study subjects consisted of 70 TS females with 45,X karyotype (mean age 18.3 (SD 7.5) years) and their 50 female family members as controls (mean age for mothers 37.2 (SD 7.4) years and for sisters 17.4 (SD 7.9) years). All study subjects are from Alvesalo's Kvantti Research Project. The tongue position was evaluated from the lateral cephalograms. Dental casts were used to measure the palatal width and height dimensions and to visually evaluate the presence of lateral palatine ridges. The difference of the tongue position between TS subjects and the controls was assessed by independent sample t-test. The one-way ANOVA was used to evaluate the relationship between lateral palatine ridges, tongue position and palatal dimensions.
Results: The distance of the tongue from the palatal plane was significantly longer in the TS subjects compared with the controls (10.9 (SD 4.0) mm vs. 7.6 (SD 3.4) mm, respectively; p < 0.001), indicating a low tongue position in TS. Prominent lateral palatine ridges were present in 25 TS subjects, 25 TS subjects had small and 20 TS subjects had no lateral palatine ridges. The TS subjects with prominent palatal ridges had significantly narrower posterior palates compared with the TS subjects with normal palates (29.5 (SD 3.1) mm vs. 31.5 (SD 2.2) mm, respectively; p < 0.05).
Conclusion: Turner females showed low tongue position. Prominent lateral palatine ridges are common in TS subjects and are related to the narrowness of the posterior palate.