Hi there,
If the stems have for sure wilted, then I would absolutely cut the whole dead stem out right down to the ground regardless of pruning group. You'll know it's wilt if the green growth (and maybe flower buds) suddenly withered over and died. If it's just dead from, lets say, drying out, getting damamge or being too old, you could just cut out the dead growth back to some live stem/wood. Hope this helps! :)

thanks for the come back,i will try what you said.