ASK THEM IF THIS WILL NEED TO BE REPEATED! My best friend had this done and they never said a word about repeat. I had read that it "usually" needs at least 2 treatments but the DENTISTS DO NOT REVEAL THAT.
Sure enough, a year later she had it done again. Ask the difference between PLANING AND SCALING AND DO THE LEAST INVASIVE. It'll make them mad but it's sufficient. I had one or the other done and it was a piece of cake. My friend had the deeper one and she bled a LOT. Plus, a repeat was necessary.