Cutler suffered a torn groin muscle during his side's 45-41 loss to the Washington Redskins on Sunday, with the Bears confirming that the first-choice quarterback would miss four weeks of action.
However, Trestman has warned that the four-week time-scale is the minimum that Cutler could miss, and that he will approach the recovery week by week after that stage.
"I'm only confident by what [the doctors] told me. This is a minimum of four weeks, and then he'll be evaluated week to week. But based on the history - I talked to the doctors this morning - four weeks is a reasonable start, and then it would be week to week," Trestman told reporters.
"Jay's injury has been highly documented. I read a paper that the doctor gave me that says this is the kind of injury he has, and there's a lot of different ways to go about doing it, but the best is just rest and recovery."