Most modern English learner's dictionary use controlled defining vocabulary for defining lemmas. Which Italian learner's dictionaries incorporate controlled defining vocabulary?
The only monolingual Italian learner's dictionary I have found is Dizionario italiano per stranieri, published by Giunti Demetra at its series Scuola d'italiano. I don't have this dictionary, but I have seen it in an Italian bookstore, so I could have a look. The definitions seem quite easy to understand, so I think it can be a good resource for an intermediate Italian learner. This dictionary is quite small and light enough to be carried out easily.
Maybe this is not a complete answer to the OP question because I don't know if they have really used a controlled defining vocabulary, but this is the only thing similar to what it's asked I've been able to find.