I assume you are referring to the incisors? If so, your vet can safely extract them. There’s nothing that can be done for recessed gums-I think what your vet was trying to explain that once tartar and calculus have been removed/scaled from the tooth often the gums will re-adhere-that’s different from recession. The technician will actually be helping that process by root planning.
Have the incisors extracted. If you are referring to the canines-well, that’s a different matter -those can be difficult extractions (and as previously mentioned require a flap)-esp in long, narrow nosed dogs. If it’s the canines-I highly recommend seeking a veterinary dentist to perform the procedure.