Roethlisberger, who is dealing with a left ankle injury, was a full participant in practice the last two days after being limited on Wednesday.
The star quarterback initially hurt his ankle during a December 8 game against the Browns, but was able to finish the contest. He then started the following week against San Francisco, but was limited in his mobility. He missed Week 16 against the Rams before coming back to play in the regular-season finale against Cleveland.
Pittsburgh will likely be without starting center Maurkice Pouncey on Sunday. Pouncey missed the last two days of practice this week with an ankle injury, and reports indicate he will miss the game.
Guard Doug Legursky would replace Pouncey at center.
Cornerback Cortez Allen (shoulder) and running back Mewelde Moore (knee) are out for the Broncos game.
In other news for Pittsburgh, running backs coach Kirby Wilson was hospitalized after suffering burns to his arms and legs in a house fire early Friday morning.
He will not travel with the team for Sunday's game.
"First and foremost our thoughts and prayers are with Kirby and his entire family," Steelers president Art Rooney II said in a statement. "We are saddened to hear about this unfortunate situation but we know that he has the best medical care in the country treating him. The entire organization is praying for Kirby to have a full recovery and we will be by his side through this difficult time."