Mollie Parsons, 42, had been set to go to trial Wednesday. She was sentenced to the maximum 10 years in prison after entering her guilty plea to involuntary manslaughter, failing to provide for a functionally impaired child and tampering with records.
The nurse's plea was not part of an agreement with prosecutors and did not win her leniency. Parsons had faced as little as three years in prison.
It was Parsons' job to administer care to Makayla six days a week at her Dayton home, where she lived with her mother, prosecutors said.
The teen had numerous bedsores and was living in filthy conditions when she died from nutritional and medical neglect complicated by cerebral palsy in what a coroner said at the time was the "worst malnourished child" his office had ever seen, authorities said.
"She basically starved to death," Montgomery County Prosecutor Mat Heck said Tuesday. Parsons "had a duty, a responsibility, an oath that she took as a nurse to care for people, and in this particular case, this is one of the most dependent victims she would ever come in contact with in her entire life, and she simply failed to do anything."
"It's one of these cases that cries out for justice," Heck added.
Parsons' attorney, Jon Paul Rion, did not return a call for comment Tuesday.
Heck speculated that Parsons changed her plea to guilty to avoid having any more details about Makayla's death come out at trial.
The girl's mother, Angela Norman, is already serving a nine-year sentence stemming from her death. Two other Ohio nurses with less significant roles in the girl's care, Mary Kilby of Miamisburg and Kathryn Williams of Englewood, were sentenced to up to five years of probation in the case last month.
Prosecutors say Williams was supposed to supervise Parsons, visit and inspect the living conditions, and do a physical assessment of the girl every 30 to 60 days, and Kilby was scheduled to visit every six months to check on conditions in the home and assess the girl's health, needs and care.