Howell, 22, put pen-to-paper on a one-year contract extension last week after an impressive 2008/2009 campaign in which he started nine of the Dons last 11 games.
"I'm very please to have signed - it's taken some time to sort it all out but I'm excited about next year and being involved with a club moving forward," he told the club's official website.
"I had to be patient in waiting for a chance to play, but when that chance came along I grew in confidence the more games I played and I think that showed in my performances. It was just a shame the season didn't finish as we'd hoped.
"It's going to be tough to hold down a regular place in the team next season. If the team is up there competing again then it's natural that there will be a lot of quality players competing for the same positions.
"I'm quite young but I feel as though I can do it. If I stay fit I think I can hold onto a place in the team."