Greg Davis, 17, confessed to sexually assaulting 89-year-old Rachel Cornell at the Chatham Creek Rest Home in June 2003.
"I apologize for my actions. I was not in my right state of mind, and there's no words to describe what I did," Davis said Monday.
Judge James Spencer sentenced Davis to up to 30 years in prison. Spencer said seniors deserve respect, not rape.
"This kind of action is the very worst kind of indignity that these folks can be made to suffer," he said.
John Cornell, Rachel's son, was pleased with the sentence, but had mixed feelings about Davis' apology.
"It was a comfort to some degree, but I don't know his heart. Only God knows his heart, and I don't know what he said he really meant it or whether he didn't. Only God would know that," he said.
The attorney for the Cornell's family said he has a lot of safety concerns about the rest home. Davis agreed to help the attorney and the victim's family in gathering information for a potential lawsuit.