  We consider the most general renormalizable theory of propagating torsion in
Einstein gravity for the Dirac matter distribution and we demonstrate that in
this case torsion is a massive axial-vector field whose coupling to the spinor
gives rise to conditions in terms of which gravitational singularities are not
bound to form; we discuss how our results improve those that are presented in
the existing literature, and that no further improvement can be achieved unless
one is ready to re-evaluate some considerations on the renormalizability of the
theory.
