John Towns’ dog latched on to the face of the two-year-old girl at his home in Forfar when she went to stroke it.
The Staffie then, “without warning”, knocked the child over and bit her face in a “tight grip”.
The girl’s mother had to wrestle with the animal to get it to release its powerful jaws - only for it to tighten its grip before finally letting go.
The toddler lost teeth and was left with two “large, gaping wounds” on her cheeks, Forfar Sheriff Court heard.
She may require plastic surgery to repair the damage caused in the vicious attack.
Towns now faces jail and the dog faces being put down when the case calls again next month.
Fiscal depute Joanne Smith told the court that the young victim’s mother was a friend of the couple and had visited their home around 10.30am on February 27.
The girl first went upstairs then came back down to the living room to stroke the dog gently on the back.
Miss Smith said: “Suddenly, and without warning, the dog knocked the child over and held the child’s face in its mouth in a tight grip.”
The mother tried to prise the dog’s jaws open and eventually managed to release it after a struggle.
The prosecutor added: “There were two large gaping wounds on her cheeks and some of her teeth were missing.”
The six-year-old dog, which Towns had owned since it was a puppy, was described as “excitable” and growled at police who attended.
Towns was in the garden when the attack took place and was found shouting at his partner, Elaine Towns, when police turned up.
Miss Smith said there had been a “significant improvement” in the child’s injuries since the attack but that she may still need plastic surgery as a result.
The dog was removed from the house and has been held in kennels since. The Crown moved for the dog to be destroyed.
Towns, 45, of Glamis Road, Forfar, pleaded guilty on indictment to a charge of being the owner of an animal that was dangerously out of control and permanently disfigured the toddler on February 27 this year.
His not guilty plea to supplying diazepam from his home on the same date was accepted by the Crown.
His partner, Elaine Towns, 39, had her not guilty plea to the dog charge accepted.
Defence solicitor Nick Markowski told the court that Towns had a “significant” criminal record.
Sentence was deferred until next month for criminal justice social work background reports and Towns was released on bail meantime.
A sheriff will also rule on the Crown’s application for the dog to be destroyed on the same date.