  In mean-field approximation, the SU($4$) Polyakov linear - sigma model (PLSM)
is constructed in order to characterize the quark-hadron phase structure in a
wide range of temperatures and densities. The chiral condensates $\sigma_l$,
$\sigma_s$ and $\sigma_c$ for light, strange and charm quarks, respectively,
and the deconfinement order-parameters $\phi$ and $\phi^*$ shall be analyzed at
finite temperatures and densities. We conclude that the critical temperatures
corresponding to charm condensates are greater than that to strange and light
ones, respectively. Thus, the charm condensates are likely not affected by the
QCD phase transition. Furthermore, increasing the chemical potentials decreases
the corresponding critical temperatures.
