Reindex completely rebuilds the index, removing fragmentation at all levels.
Index Defrag shuffles the leaf pages into order, removing fragmentation at the leaf levels, but potentially leaving fragmentation at the other levels of the index.
Doing a defrag right after a reindex is redundant and a waste of time and server resources.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability