For two days, the David L. Lawrence Convention Center will convert into a space where medical volunteers and professionals will provide free care for hundreds of people.

Mission of Mercy Pittsburgh is hosting its annual free medical clinic, an event that began at Duquesne University's A.J. Palumbo Center in 2017 with 667 patients.

Doors will open at 6 a.m. on Friday and Saturday and will stay open until capacity is reached. Last year, more than 676 people were served, nearly three times the original number. Mission of Mercy Pittsburgh plans to have about 2,000 volunteers from various medical fields to handle the influx of patients.

"I just want to say thank you to all of them, because we could not make this happen," said Keith Young, the event's administrative director and a Mission of Mercy board member. "But we need a lot of general volunteers because it takes a whole army to make this work."

Those numbers include about 150 dentists, 35 audiologists, and 35 optometrists and ophthalmologists. Young said organizers start preparing for this event eight months in advance, and they volunteer their time and expertise -- at the expense of their own revenue lost from their respective practices.

They do it to provide dental, vision and hearing care for those in the community who either can't afford care or don't have access to it.

"You don't want to put off your care," said Young. "You will improve the quality of your life by seeing better. You'll improve the quality of your life by hearing."

In addition to a wide range of dental services -- including root canals, oral surgery and pediatric dentistry -- there are also free eye exams, eyeglasses, hearing tests, and hearing aids provided. Young shared the story of a woman whose hearing was tested by an audiologist, and she was given new hearing aids.

"When he was done, he turned to her and said, 'Can you hear me?'" said Young. "And she just started crying, and she looked up at him and said, 'I haven't heard a human voice in 30 years.' That's amazing."

The event is first-come, first-served. Organizers warn there will be long waits throughout the day, but they do not want that to stop anyone from getting the care they may seriously need.

"We actually had a gentleman three years ago who came in, and they removed all of his upper teeth," Young said. "The dentist told him, 'If you hadn't come in, you would've been dead in two months.' It's that serious."

In addition to potentially saving and altering lives, organizers also want to treat every patient who enters with dignity and respect.

"We want to provide quality health care, absolutely," Young said. "But we want them to leave feeling, 'I had a really good experience, and I meant something to these people.' That's critical, and we actually train our volunteers to do that."

Free dental, hearing and vision clinic returns to Pittsburgh this week