  We study the impact of higher order quark-meson scattering processes on the
chiral phase structure of two-flavour QCD at finite temperature and quark
density. Thermal, density and quantum fluctuations are included within a
functional renormalisation group approach to the quark-meson model. We present
results on the chiral phase boundary, the critical endpoint, and the curvature
of the phase transition line at vanishing density.
