  We propose a chemical potential dependent effective gluon propagator and
study the chiral quark condensate in strongly interacting matter in the
framework of Dyson-Schwinger equation approach. The obtained results manifest
that, as the effect of the chemical potential on the effective gluon propagator
is taken into account, the chiral quark condensate decreases gradually with the
increasing of the chemical potential if it is less than the critical value, and
the condensate vanishes suddenly at the critical chemical potential. The
inclusion of the chemical potential in the effective gluon propagator enhances
the decreasing rate and decreases the critical chemical potential. It indicates
that the chiral symmetry can be restored completely at a critical chemical
potential and restored partially as the chemical potential is less than the
critical value. If the effective gluon propagator is independent of the
chemical potential, the chiral symmetry can only be restored suddenly but no
gradual restoration.
