The three largest modes of variation in hard palate shape, determined in completely data-driven fashion, without imposing any prior notions about expected shape variations, by applying PCA to the observed hard palate shapes from the subject pool. Modes reflect differences in concavity, anteriority of the apex, and sharpness of the palate around the apex. The overall mean hard palate shape is shown in black, and the blue and red lines show the nature of deviations from the mean according to each mode. The magnitude of the deviations shown reflect the magnitude of variations seen in the subject pool, at precisely +/- 1.5 standard deviations from the mean shape. Because these modes account for over 85% of the overall variance, arbitrary hard palate shapes may be well-represented using only these three modes.