Dickinson, a summer signing from Derby, picked up an ankle knock during Saturday's defeat by Walsall and was unable to train on Monday - although he will still travel to Wales.
Boss Russell Slade does have options in attack as Nicky Forster (knee) and Glenn Murray (groin) were able to make substitute appearances at the weekend and Craig Davies (knee) has resumed training.
But fellow frontman Gary Hart is still a couple of weeks away with a toe injury.
Left-back Jim McNulty is the Seagulls' only other absentee, and he is continuing to make good progress from the horrific kidney injury he suffered last season.
