pull the plant from the pot and knock off potting media from around the root ball
inspect the now cleaned roots ....they should be white & firm - but not shriveled and squishy ....
Next ....remove any roots that are shriveled or squishy - cut back to solid "wood" ....removing any mushy parts
before the plant is re-potted / watered ....the cut areas must harden, "callus over" (dry out) ....this will take about 5-14 days (depending on local humidity)
next ....amend your potting soil to make it more "rocky" or "gritty" .....by adding coarse sand, pebbles & rocks .. this will improve drainage
New growth should reappear once the plant re-adjusts - be patient - as adeniums seem to take forever to re-adjust