What does it mean when the dental Hygienist scrapes your gum line and calls out !

This is the pocket depth of your teeth. A periol probe has marking on it in millimeters and she will poke down around the gum margin to see how far the gum goes down and if gum disease is present.

I am a dental nurse in the UK

The hygienist is using a tool that she puts between the gums and the tooth and the instrument has measurements. I think these are the numbers you are referring to. They indicate how healthy your gums are. The further down the tool can go, separating the gums from the teeth, the less healthy the gums are.

I once asked a hygienist about those numbers (a long time ago) and this is what I remember her telling me.

The numbers are usually your teeth, i.e left bottom 6 is a back tooth, 1 + 2 are your fronts and so on.

measuring your gum line