  We explore dust flow in the hottest parts of protoplanetary discs using the
forces of gravity, gas drag and radiation pressure. Our main focus is on the
optically thin regions of dusty disc, where the dust is exposed to the most
extreme heating conditions and dynamical perturbations: the surface of
optically thick disc and the inner dust sublimation zone. We utilise results
from two numerically strenuous fields of research. The first is the
quasi-stationary solutions on gas velocity and density distributions from
mangetohydrodynamical (MHD) simulations of accretion discs. This is critical
for implementing a more realistic gas drag impact on dust movements. The second
is the optical depth structure from a high-resolution dust radiation transfer.
This step is critical for a better understanding of dust distribution within
the disc. We describe a numerical method that incorporates these solutions into
the dust dynamics equations. We use this to integrate dust trajectories under
different disc wind models and show how grains end up trapped in flows that
range from simple accretion onto the star to outflows into outer disc regions.
We demonstrate how the radiation pressure force plays one of the key roles in
this process and cannot be ignored. It erodes the dusty disc surface, reduces
its height, resists dust accretion onto the star, and helps the disc wind in
pushing grains outwards. The changes in grain size and porosity significantly
affect the results, with smaller and porous grains being influenced more
strongly by the disc wind and radiation pressure.
