After a long absence from the dentist I finally went six months ago, had x rays, the cleaning procedure and had a back tooth extracted. That was me done. I went for my check up yesterday and there's something I'm curious about. The dentist was using some instrument on the base of my teeth and he kept saying 'zero' to the nurse who was recording the information. I'd never had this done before, the only thing I can think of is he was checking for pockets, but I find it difficult to believe I have no pockets even though he said my gums had improved a lot since my last visit. Is there any other test they do that would require him to shout out zero many times. I really wish I'd have asked him but, quite frankly, I couldn't get out the door quick enough. If anyone could help with this I'd be very grateful. Thank you.