De or het paneldiscussie?

The correct Dutch article is:

de paneldiscussie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use paneldiscussie

the paneldiscussiede paneldiscussie
this paneldiscussiedeze paneldiscussie
that paneldiscussiedie paneldiscussie
our paneldiscussieonze paneldiscussie
your paneldiscussiejouw paneldiscussie
every paneldiscussieelke paneldiscussie
which paneldiscussie?welke paneldiscussie?
a big paneldiscussie / the big paneldiscussieeen grote paneldiscussie, de grote paneldiscussie