Two owners of the company that makes OxyContin acknowledged to Congress on Thursday that the powerful prescription painkiller played a role in the opioid epidemic but they stopped short of apologizing or admitting wrongdoing.“I want to express my family’s deep sadness about the opioid crisis,” David Sackler, whose family owns Purdue Pharma, said at a rare appearance in a public forum. “OxyContin is a medicine that Purdue intended to help people, and it has helped, and continues to help, millions of Americans.”The company’s …