Collins Cobuild term verbs such as be, remain, look, and turn link verbs, some of which take an 'adjective complement'. Certainly, Her teeth were etc need some form of completer. A snag is that one can't really sensibly separate syntax and semantics here. Be in this usage is certainly just a placeholder, whilst turn has added semantic content (as well as linking descriptor of final state back to the subject's referent).
In passing, these link-verb constructions, those link-verb constructions that also take an object, and the similar constructions using verbs not truly link verbs described below, can describe the initial state of the subject's referent (He was eaten alive), the final (He was shot dead), the prevailing (He stood there motionless) or the desired (They wished him dead). Notice that the adjective may or may not be syntactically mandatory; it is certainly semantically significant (except perhaps in 'He was eaten alive').
Cobuild also mentions 'other verbs taking complements' though these are usually if not always syntactically optional. These latter verbs carry significant semantic weight, as well as syntactically linking in the way link verbs do. Perhaps they should be called 'link-like verbs'. Where semantic weight becomes telling enough to disqualify from true link-verb status is of course open to debate. Examples of usage:
Alexander lies dead in the field.
Her brother escaped unharmed.
Her blood ran cold.
Her teeth gleamed white against the tanned skin of her face.
Given that unharmed is an optional element syntactically whilst cold is arguably syntactically necessary (Her blood ran would mean something different), one wonders about the value of using different terms to analyse these structures. 'Being necessary' is often an arguable property of word groups.