The 20-year-old has been a big success at Victoria Park during his spell which began in August, making 16 appearances and scoring one goal.
He will now stay with Pools until January 4 as Colin Cooper's men look to push up the League Two table.
"We're delighted that we've been able to extend Matty's stay again," Cooper told the club's official website.
"It's great that we've been able to get the deal done with Middlesbrough and I'd like to thank them for their help with it.
"Now Matty can get his head down and concentrate on what will be a busy period of games taking us through in to the new year."