[Closed] mouth control 2

hi, at present i’m working with face animation, i decided to simulate muscles (boxes) and use skin modify… even result is not bed (with facial expressions) … but now i have problem how to control mouth because when i’m using skin modify the result is not good because mouth are a lttle bit part (see figure) so some vertexs does not know to which musles belong to (with mouth there is need of precision) … and i’m wondering with method is good for it ?? and how to combine it with other muscles ? thx