[dmreedy]

Tongue contact might be sufficient (in linguistics, two of the axes of "pronunciation space" are "dental" (whether the tongue makes contact with the teeth) and "palatal" (whether the tongue makes contact with the palate).

There are a number of other dimensions however that are equally important in the creation of word-sounds (e.g., whether the lips are pursed, whether the vocal folds are vibrating, whether the teeth make contact with the lips, where the tongue is located in the space of the mouth [for vowels], etc) and would make determination just from the dental/palatal axes pretty difficult I think. But maybe with enough context, you could get something predictive that is more than good enough, even if it's not into deterministic territory