Are such moments allowed in retopology?

Question

3D

I've heard that it's better to avoid N-gons in retopology, but in this case, I don't even know how to make a character's mouth NOT creating loops along the whole body and without doing what I did in the picture below:

Answer 1

Your case is 4-1

Answer 2

I would just triangulate, anyway, the system eventually works with triangles. Well, either, if you need quadrilaterals, then yes, only let three loops, which will greatly complicate the mesh and model.