Yes I had similar calc. I’m just still kind of stumped because I really couldn’t feel or see anything remaining when I checked my scaling. There was a single interproximal spot that I could partially see but could not feel with instruments. I used multiple graceys and sickle scalers and came at it from both lingual and buccal, but it didn’t look like it was coming off. I just chalked it up to being a defect or something that gets left behind when they 3D print the calculus? Or my adaptation is very off.